• Microbiology and Biotechnology Letters
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• v.43 no.4
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• pp.385-390
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• 2015

In order to develop an eco-friendly biofertilizer, a plant growth promoting rhizobacterium (PGPR), Bacillus sp., SH1RP8 was investigated. SH1RP8 was lyophilized via freeze-drying along with other protective agents that protect cells from lysis. The freezedried powder of Bacillus sp. SH1RP8, containing 5% skim milk (w/v), exhibited the highest survival rate of 30.6% among all the protective agents (skim milk, glucose, and peptone). The lyoprotective effect of the skim milk, mixture including 5% skim milk, and substrates on the survival of the test strain was examined. Control group was added only skim milk and test groups were added skim milk and other substrates. As a result, the group supplemented with both glycerol and 5% skim milk showed the protective effect much higher by 214.29% than the control group. Freeze-dried Bacillus sp. SH1RP8 could be a good candidate as a potential biofertilizer due to its effective PGPR activity.

• Applied Chemistry for Engineering
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• v.29 no.6
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• pp.703-709
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• 2018

Dielectric heating materials were prepared through the thermal treatment for composites of Li and Zn type precursors that are major materials being responded to microwave under diversified conditions. The prepared heating material samples were analyzed by SEM and it was confirmed that $Li_5Fe_5O_8$ materials being formed on the surface was a major influencing factor for the heating performance. Heating materials improved the moisture removal in a sludge drying facility, for example, the moisture content of 25 v/v% sludge decreased to 15.22 v/v%. Accordingly, heating materials were confirmed to directly affect the performance and efficiency of the microwave drying process.

• Journal of Energy Engineering
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• v.28 no.1
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• pp.17-21
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• 2019

Calcium sulfaluminate (CSA) was synthesized to improve the shrinkage of OPC. In this study, the setting time, the compressive strength and the length change ratio were confirmed by replacing the synthesized CSA with OPC by 10% and 13% by 16%. In the case of shrinkage-reducing type cement, formation of Ca-Al-$H_2$-based hydrate was activated. Therefore, the setting time was shortened. The compressive strength of the shrinkage - reducing type cement is comparable to that of OPC after 7 days' strength. However, shrinkage reducing type cement showed improved initial strength compared to OPC. The length change ratio was found to be improved by drying shrinkage from -0.075% to -0.047% on the 28th day.

• Food Engineering Progress
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• v.21 no.1
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• pp.42-48
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• 2017

The purpose of this study was to verify the drying characteristics of steamed sweet potato and to establish optimal drying conditions for far-infrared drying of steamed sweet potato. 4 kg of steamed sweet potato was sliced to thicknesses of 8 and 10 mm, and dried by a far-infrared dryer until a final moisture content of $25{\pm}0.5%$. The far-infrared dryer conditions were an air velocity of 0.6, 0.8 m/s and drying temperature of 60, 70, and $80^{\circ}C$. The results can be summarized as follows. The drying time tended to be reduced as temperature and air velocity for drying increased. The Lewis and Modified Wang and Singh models were found to be suitable for drying of steamed sweet potato by a far-infrared dryer. The color difference was 35.09 on the following conditions: Thickness of 8 mm, temperature of $80^{\circ}C$, and air velocity of 0.8 m/s. The highest sugar content ($59.11^{\circ}Brix$) was observed on the conditions of a thickness of 8 mm, temperature of 80, and air velocity of 0.8 m/s. Energy consumption decreased on the conditions of higher temperature, slower air velocity, and thinner steamed sweet potato.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.2
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• pp.73-78
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• 2022

This experiment was conducted to establish the technology for artificial hay preparation in Korea. Using far-infrared heater, a device that can control temperature, airflow, and far-infrared radiation was produced and conducted on the fourth harvested alfalfa. The drying conditions were carried out by selecting a total of four conditions. For each condition, the radiation rate was set to around 40% (33-42%), and the temperature was set at 58~65℃, and the speed of the airflow was fixed at 60m/s. The overall drying time was set to 30 min in the single and 60 min (30-30 min) and 90 min (30-30-30 min) in the complex condition, and the radiation rate and temperature were changed by time period. In the case of drying condition 1, the final dry matter (DM) content was 46.26%, which did not reach a DM suitable for hay. However, all of the alfalfa corresponding to the remaining drying conditions 2 to 7 showed a DM content of 80% or more, resulting in optimal alfalfa hay production. In power consumption according to the drying conditions, the second drying condition showed the lowest at 4.7 KW, and the remaining drying conditions were as high as 6.5 to 7.1 KW. The crude protein content was found to be high at an average of 25.91% and it showed the highest content in the 5th drying condition (26.93%) and the lowest value in the 6th drying condition (25.16%). The digestibility showed a high value with an average of 84.90%, and there was no significant difference among treatments (p>0.05). Considering the above results, it was judged that drying condition 2 was the most advantageous.

• Journal of Korean Institute of Industrial Engineers
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• v.41 no.1
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• pp.97-104
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• 2015

An electric-motor which uses electric energy to dry laundry in a dryer generates wind by rotating a fan. The roles of electric motor and fan are crucial for drying. To reduce the noises or vibration, their performances should be improved. However, it requires a relatively high cost to redesign them. In this case, redesigning the fan case rather than the motor or the fan would be easier and cheaper. This paper is to apply Taguchi dynamic characteristic concept with the ideal function of energy conversion to redesign the fan case. Not only the increase of the wind power but also the decrease of noise, vibration and the other side effects are resulted.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1994.05a
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• pp.98-102
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• 1994

천연가스의 주성분인 순수 메탄에 대한 촉매 산화반응은 Pd촉매가 가장 양호하나 LP가스의 주성분인 프로판에 대해서는 Pt촉매가 가장 양호한 결과를 보였다. 그러나 유황 피독된 Pd촉매는 메탄에 대해 영구피독 현상을 보였고, fresh한 Pd촉매는 연료 중 미량의 유황분량에 의해 반응 개시온도가 지연되는 경향을 보였다. 이와 같은 촉매독 영향이 적은 Rh촉매버너를 개발하여 8000시간 이상 성공적인 연소 실험을 하고 있으며 C 방적의 염색 시험기에 적응 실험한 결과 기존의 적외선 전기 건조기에 비해 에너지 절감은 약30-40%를 기하였고 연료비는 70-80%의 절약효과를 얻었다.

• Journal of Electrochemical Science and Technology
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• v.4 no.1
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• pp.19-26
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• 2013

Graphene/Ni-Al layered double hydroxide (LDH) hybrid materials were synthesized by a hydrothermal reaction. Hexagonal Ni-Al LDH particles nucleated and grew on graphene sheets, thus preventing restacking of the graphene sheets and aggregation of the Ni-Al LDH nanoparticles upon drying. Electrode made from the graphene/Ni-Al LDH hybrid materials showed a substantial improvement in electrochemical capacitance relative to those made with pure Ni-Al LDH nanoparticles. In addition, the graphene/Ni-Al LDH hybrid composite materials showed remarkable stability after 4000 cycles with over 100% capacitance retention. These materials are thus very promising for use in electrochemical capacitor electrodes.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.205-208
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• 2006

Existing gas fired burners work in the medium wave IR range at $1000^{\circ}C$ and an energy density of $200kW/m^{2}$. The patented porous burner technology reaches the short wave IR spectrum ($1450^{\circ}C$) and comes up to an energy density of $1000kW/m^{2}$. This technology is of great interest for various applications in paper industry. Speeding up existing coating lines can be realized without a major revamp of the line. Main characteristics of this new developed technology enable a better process control. In this paper the porous burner technology for paper industry is evaluated.

• Current Photovoltaic Research
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• v.2 no.1
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• pp.36-39
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• 2014

Formation mechanism of residual carbon layer, frequently observed in the $CuInSe_2$ (CIS) thin film prepared by direct solution coating routes, was investigated in order to find a way to eliminate it. As a model system, a methanol solution with dissolved Cu and In salts, whose viscosity was adjusted by adding ethylcellulose (EC), was chosen. It was found that a double layer, a top metal ion-derived film and bottom EC-derived layer, formed during an air drying step presumably due to different solubility between metal salts and EC in methanol. Consequently, the top metal ion-derived film acts as a barrier layer inhibiting further thermal decomposition of underlying EC, resulting a formation of bottom carbon residue layer.