Transition metal oxides formed by a single or heterogeneous combination of transition metal ions and oxygen ions have various types of crystal structures, which can be classified as layered structures and non-layered structures. With non-layered structures, it is difficult to realize a two-dimensional structure using conventional synthesis methods. In this study, we report the synthesis of cobalt oxide into wafer-scale nanosheets using a surfactant-assisted method. A monolayer of ionized surfactant at the water-air interface acts as a flexible template for direct cobalt oxide crystallization below. The nanosheets synthesized on the water surface can be easily transferred to an arbitrary substrate. In addition, the synthesizing morphological and crystal structures of the nanosheets were analyzed according to the reaction temperatures. The electrochemical properties of the synthesized nanosheets were also measured at each temperature. The nanosheets synthesized at 70 °C exhibited higher catalytic properties for the oxygen evolution reaction than those synthesized at other temperatures. This work suggests the possibility of changing material performance by adjusting synthesis temperature when synthesizing 2D nanomaterials using a wide range of functional oxides, resulting in improved physical properties.

This study was conducted in an indoor cultivation room and chamber where environmental control is possible to investigate the effect of temperature and irrigation interval on photosynthesis, growth and growth analysis of potted seedling cucumber. The light intensity (70 W·m-2) and humidity (65%) were set to be the same. The experimental treatments were six combinations of three different temperatures, 15/10℃, 25/20℃, and 35/25°C, and two irrigation intervals, 100 mL per day (S) and 200 mL every 2 days (L). The treatments were named 15S, 15L, 25S, 25L, 35S, and 35L. Seedlings at 0.5 cm in height were planted in pots (volume:1 L) filled with sandy loam and treated for 21 days. Photosynthesis, transpiration rate and stomatal conductance at 14 days after treatment were highest in 25S. These were higher in S treatments with a shorter irrigation interval than L treatments. Total amount of irrigation water was supplied evenly at 2 L, but the soil moisture content was highest at 15S and lowest at 25S > 15L > 25L, 35S and 35L in that order. Humidity showed a similar trend at 15/10℃ (61.1%) and 25/20℃ (67.2%), but it was as high at 35/25°C (80.5%). Cucumber growth (plant height, leaf length, leaf width, chlorophyll content, leaf area, fresh weight and dry weight) on day 21 was the highest in 25S. Growth parameters were higher in S with shorter irrigation intervals. Yellow symptom of leaf was occurred in 89.9% at 35S and 35L, where the temperature was high. Relative growth rate (RGR) and specific leaf weight (SLA) were high at 25/20℃ (25S, 25L), RGR tended to be high in the S treatment, and SLA in the L treatment. Water use efficiency (WUE) was high in the order of 25S, 25L > 15S > 15L, 35S, and 35L. As a result of the above, the growth and WUE were high at the temperature of 25/20℃.

수경 재배한 멜론의 생육과 수확 후 모의유통 시 품질 차이를 검토하였다. ‘루비볼춘추계’의 수경재배 된 멜론을 이용하여 저장 온도를 2℃와 5℃, 10℃, 20℃하여 모의유통 시 특성과 가용성고형물(SSC), 경도, 생체중 변화, 외관 등의 변화를 조사하였다. 멜론을 상온으로 유통하는 조건 하에서 저온저장에 따른 과실 특성을 본 연구에서 확인하였다. 멜론 저장 시 가용성고형물, 경도, 생체중, 외관이 저장온도에 따라 차이를 보였다. 가용성고형물은 멜론을 저온(2~5℃)에서 저장하여 모의유통 된 것이 상온(20℃)에서 다른 온도처리보다 높은 수준인 것으로 나타났다. 외관과 경도는 모의유통 중 저장 온도에 따른 영향이 지속적이지는 못하였지만 유통초기 저온(2~10℃) 저장이 외관 지수 및 경도 수치가 높은 경향이었다. 저장 온도에 따른 영향이 모의유통 시 계속 효과를 유지하지 못하여 국내 유통 시 이를 고려하여야 할 것이다. 본 연구 결과, 저장 온도에 따른 모의유통 중에 미치는 영향은 저장 직후 짧은 단기간에만 효과를 유지하여, 국내 유통 하에서 저장할 경우에는 바로 소비할 수 있도록 유도해야 할 것으로 생각된다.

This study monitored temperature using electronic sensors and developed a prediction model for compost maturity. The experiment used swine manure in a mechanical composting facility equipped with a screw-type agitator, and the composting process was conducted for 60 d during the summer season in South Korea. Four electronic temperature sensors were installed on the inner wall between the compost piles on Days 7, 14, 21, and 28 for daily temperature monitoring. Compost samples were collected daily for 60 d, and compost maturity was analyzed using the Solvita method. Multiple comparisons, correlations, and modeling were performed using the stat package in R software. The average compost pile temperatures was 39.1±3.9, 36.4±4.3, 31.3±4.5, and 35.4±8.1 on days 7, 14, 21, and 28, respectively, after composting. The average compost maturity according to the composting date was 3.61±0.60, 4.13±0.59, 4.26±0.47, and 4.32 ±0.56 on days 7, 14, 21, and 28, respectively. A significant negative correlation was observed between the compost composting periods (seven, 14, 21, and 28 d) and the temperature of all compost piles (p<0.05), where the correlation coefficients were -0.329, -0.382, -0.507, and -0.634, respectively. A significant positive correlation was observed between the compost composting periods (seven, 14, 21, and 28 d) and the maturity of the compost (p<0.05), where the correlation coefficients were 0.410, 0.550, 0.727, and 0.840, respectively. The model for predicting the maturation of the 14 d average compost pile according to the compost composting period and the average temperature for 14 d was y=0.026 x d – 0.021 x mt.x_14 d (mean temperature for 14 d) + 4.336 (R2=0.7612, p<0.001). This study can be considered a basic reference for predicting compost maturity by the proposed model using electronic temperature sensors.

목적 : 온열 안구 마사지기 사용 시 실시간으로 눈꺼풀 온도 및 눈물막 파괴 시간을 측정하여 차이를 평가하고 자 하였다. 방법 : 연구 대상은 성인 30명 (23.7±2.60세)을 대상으로 하였고 OSDI설문지 점수에 따라 건성안 그룹과 정 상안 그룹으로 나누었다(건성안 15명, 정상안 15명). 온열 안구 마사지기는 OA-MA011(OA, Seoul, Korea), OA-MA 030(OA, Seoul, Korea), DP-EM50(Caremedi, Hanam, Korea)를 사용하였고, A400 열화상카메라 (FLIR, Wilsonville, Clackamas County USA) 사용하여 착용 전과 후 1, 3, 5, 10, 15분 측정하고, 탈거 후 5, 10, 15분 시간별로 측정 후 평균값을 기록하였다. 그리고 Kekatography 5 m(OCULUS, Wetzlar, Germany)를 사용하여 마사지기 착용하기 전과 착용 15분 뒤에 눈물막 파괴 시간을 측정해서 비교 분석하였다. 결과 : 15분 착용 시 눈꺼풀 온도는 건성안 그룹은 39.77±0.69℃, 정상안 그룹은 39.57±0.77℃ 측정되었 으며, 눈꺼풀 온도 측정 시 건성안, 정상안 그룹 모두 5분 이상 착용 시 통계적으로 유의성이 있었다(p=0.033). 눈물막 파괴시간은 착용하기 전보다는 향상이 있었지만 정상범위에 못 미치는 것으로 확인하였고 건성안에서는 통 계적으로 유의성이 있었지만(p=0.041) 정상안 그룹에서는 통계적으로 유의성이 없었다(p=0.084). 결론 : 안구건조증으로 인한 개선 방법으로 안구마사지기를 사용했을 때 10분 이상 착용 시 눈꺼풀 높은 온도 에서 유지가 되었고 눈물막 파괴 시간은 15분 이상 착용 및 온도 40℃ 유지 시 눈물막 파괴 시간에 영향을 줄 수 있었다. 따라서 온열 기능의 마사지기를 사용 시 정확한 사용 방법과 눈꺼풀 온도가 유지되며 착용 시간은 충분한 상태에서 진행해야 할 것으로 사료 된다.

In this study, crystallization was effectively suppressed in Al-based metallic glasses (Al-MGs) during pulverization by cryo-milling by applying an extremely low processing temperature and using a surfactant. Before Al-MGs can be used as an additive in Ag paste for solar cells, the particle sizes of the Al-MGs must be reduced by milling. However, during the ball milling process crystallization of the Al-MG is a problem. Once the Al-MG is crystallized, they no longer exhibit glass-like behavior, such as thermoplastic deformation, which is critical to decrease the electrical resistance of the Ag electrode. The main reason for crystallization during the ball milling process is the heat generated by collisions between the particles and the balls, or between the particles. Once the heat reaches the crystallization temperature of the Al-MGs, they start crystallization. Another reason for the crystallization is agglomeration of the particles. If the initially fed particles become severely agglomerated, they coalesce instead of being pulverized during the milling. The coalesced particles experience more collisions and finally crystallize. In this study, the heat generated during milling was suppressed by using cryo-milling with liquid-nitrogen, which was regularly fed into the milling jar. Also, the MG powders were dispersed using a surfactant before milling, so that the problem of agglomeration was resolved. Cryo-milling with the surfactant led to D50 = 10 um after 6 h milling, and we finally achieved a specific contact resistance of 0.22 mΩcm2 and electrical resistivity of 2.81 μΩcm using the milled MG particles.

This study was conducted to evaluate the filtration performance according to the feed temperature composed of NaCl and the operating pressure of the brackish water reverse osmosis (BWRO) process. The temperature is known that decides the filtration performance of reverse osmosis (RO). It is noted that temperature increase activates the permeate of salts due to augment of diffusivity and mass transfer. Filtration of the lab-scale RO system was performed with constant pressure and the constant flow was simulated. The salt rejection measured by the concentration of the feed and permeate was compared with water permeability and salt permeability in the conditions containing various temperatures (5, 10, 15, 20, 25, and 30℃) and pressures (10, 12, 15, and 18 bar). An increase in feed temperature from 5 °C to 30 °C caused a 4.65% decrease in salt rejection in CSM, due to an increase in salt permeability (4.06 times) rather than an increase in water permeability (2.62 times). Specific energy consumption (SEC) was calculated by using an electricity meter set in the RO system. It was expected that the SEC by the increases in temperature and pressure decreased due to the viscosity decline of the feed and the permeate flux augment, respectively. The SEC decreased by 63.4% in CSM and by 54.3% in Nittodenko when the feed temperature increased from 5 °C to 30 °C. It discussed how to operate the optimal RO process through the effect of temperature and operating pressure and the comparison of SEC.

The temperature-dependent development of Poinsettia thrips, Echinothrips americanus was studied at eight constant temperatures (15.0, 17.5, 20.0, 22.5, 25.0, 27.5, 30.0, and 32.5±1°C), 65±5% RH and photoperiod of 16L : 8D conditions. The developmental stages were divided into egg, 1st instar, 2nd instar, pre-pupa, pupa, and adult. The total developmental time in the immature stage was 40.4 days at 15.0°C and 11.6 days at 30.0°C, and it decreased with increasing temperature. The lowest temperature of the whole immature period was 10.7°C, and the cumulative temperature to complete the entire immature period was 217.4 degree days. The optimal development temperature (Topt) for the whole immature stage was estimated to be in the range of 30.51-31.21°C. Topt for each immature stage was 31.64-35.47°C at egg, 30.02-33.08°C at 1st instar, 29.16- 34.43°C at 2nd instar, 27.63-29.21°C at pre-pupa, and 29.81-30.12°C at pupa. In the analysis of the six non-linear models, Logan 6 model was the most appropriate as Zi (Weighting Factors) was 0.18.

Perilla plant is a special crop that is used as oilseed and food in Korea. Root lesion nematodes have caused great damage to perilla plants, so for effective management of root lesion nematodes, it is necessary to understand their ecology in perilla. In this study, we investigated the effect of temperature in the development of Pratylenchus penetrans (Pp) and Pratylenchus vulnus (Pv) when the nematodes infected the perilla plant. To estimate the effect of temperature, we assessed the reproduction factor (RF); final population/initial population (Pf/Pi) of these two nematode species. We used perilla plants as inoculated hosts and investigated the density of nematodes at 10 weeks after inoculation. As a result, the RF of Pp was highest at 20°C (0.41 (1st test), 2.2 (2nd test)) followed by 25, 30, and 15°C. The RF of Pv was highest at 30°C (9.84 (1st test), 31.39 (2nd test)), followed by 25, 20, and 15°C. Comparing the RF by temperature between Pp and Pv, Pv was higher than Pp at all temperatures used in the test. This study showed the optimal development temperature of Pp was 20-25°C and Pv was 30°C, respectively.