Bentonite, primarily composed of montmorillonite, plays a crucial role as one of the engineering barrier materials in a deep geological repository (DGR). The advantageous properties of montmorillonite, such as its swelling capacity, low permeability, and low thermal conductivity, make it a key component as a buffer material for isolating high-level radioactive waste from the surrounding natural environment. It has been known that the stability of montmorillonite is influenced by a wide range of pressure-temperature-composition (P-T-X) conditions relevant to the DGR environment. When considering potential geological events, of notable concerns are its interactions with groundwater or seawater at elevated temperatures, leading to safety hazards within the system. In this study, therefore, we investigated the hydration and dehydration reactions of Ca-montmorillonite with saline fluids such as NaCl and KCl solutions at elevated pressures and temperatures by conducting in-situ X-ray diffraction experiments using both a capillary sample heating cell and a resistive-heated diamond anvil cell. As a result, we observed different hydration states of montmorillonite depending on the chemical composition of fluids, i.e., tri-hydrated layers in NaCl and bi-hydrated layers in KCl solutions, respectively. Furthermore, we identified that montmorillonite undergoes distinct stepwise dehydration with increasing temperature, and the dehydration temperature of montmorillonite significantly increases with increasing water pressure. Consequently, this study would provide insights into the stability of hydrated montmorillonite in a seawater-dominated fluid environment and its implications for the long-term safety of the disposal system.

This short review focuses on fouling by proteins and macromolecules in microfiltration/ultrafiltration. First, an experimental system that enables investigation of how the extent of the adsorption of proteins and macromolecules on membrane surfaces contributes to a decrease in filtrate flux in microfiltration/ultrafiltration is described. Using this system, a causal relationship - not a correlation - indicating that adsorption results in a decrease in filtrate flux could be clearly demonstrated in some cases. Second, a hydration structure at the membrane surface that can suppress adsorption is discussed, inspired by biomaterial research. In their hydrated states, polymers with low-fouling properties have water molecules with a particular structure. Finally, some successful examples of the development of low-fouling membranes via surface modification using low-fouling polymers are discussed.

One of the most precise methods of tracking water movement and measuring moisture content during hydration process is the usage of magnetic resonance imaging (MRI). In this study, the target samples were dried “Robusta” green coffee beans, and a series of images was acquired through an MRI system during the entire hydration process. Coffee beans were immersed in a glass bottle and were placed in a 35 mm diameter RF coil throughout the whole experiment. A set of 64 images with a field of view of 26 mm×26 mm was acquired. The hydration process of intact dried green coffee beans lasted for 360 min and image data sets were acquired every 10 min with an optimal GRE pulse sequence developed. The MR images were analyzed in 2D and 3D imaging spaces. The results of 2D analysis showed that the changes in water penetration depth inside coffee beans during the hydration process could be visualized. In addition, the results of 3D analysis presented a clearer understanding of the hydration process of dried coffee beans. This study showed that changes in water distribution and physical dimensions of coffee beans during the hydration process in 2D and 3D imaging spaces were meserable, without disturbing the process, by means of the MRI technique.

Skin barrier function can be assessed non-invasively, including by transepidermal water loss (TEWL), skin hydration, and sebum level. The aim of this study was to evaluate day-to-day variation in measurements of TEWL, skin hydration, and sebum level at various anatomic sites and the relationship between these parameters in normal dogs. Measurements were repeated five times on two separate days in five clinically normal Beagle dogs at seven anatomic sites, i.e., the left and right pinnae, left and right axillae, left and right groin areas, and ventrum. Coefficient of variation was used to show the variation in measurements. Correlations between each of the measurements were analyzed to determine the contribution of skin hydration and sebum level to TEWL. There was no variation in the measurements obtained according to time or anatomic site (P>.0.05). The coefficient of variation was highest for sebum level (209.0 ± 81.8%) followed in descending order by skin hydration (62.7 ± 34.5%) and TEWL (41.1 ± 6.9%). Of the seven anatomic sites sampled, the left and right pinnae showed the lowest variation in repeated measurements for TEWL (39.2%), skin hydration (29.6%), and sebum level (75.5%). There was no significant relationship between the results for each measurement (P>.0.05). Because of its relatively low variation on repeated measurement, TEWL might be the most useful way of evaluating skin condition in dogs.

This study evaluated the hydration, gelatinization, and saccharification properties of rice processing for beverage development. The properties of rice were studied on 10 rice cultivars (Samkwang, Ilpum, Seolgaeng, Anda, Dasan-1, Goami-4, Danmi, American rice, Chinese rice, and Thai rice) and employing four kinds of pre-treatment methods (dry grain, wet grain, dry flour, and wet flour). The results showed that moisture content of rice was between 11.88~15.26%. Increase in soaking time along with highest water absorption was noted in American rice cultivar (46.81%). The water binding capacity of Thai rice was higher when compared to that of other rice flours. In addition, solubility and swelling power of rice were 4.52~26.65% and 0.19~2.05%, respectively. The amylose content of Goami-4 was higher in rice processing. Using a rapid visco analyzer (RVA), the initial pasting temperature of Danmi cultivar was found to be the highest; the peak viscosities of Anda cultivar and Dasan-1 cultivar, and Chinese rice were higher than of those of other rice flours. After saccharification, the pH, soluble solids content, and reducing sugar content of rice processed through different pre-treatment methods were in the range of 6.22~7.08, 4.67~16.07 °Brix, and 0.35~11.67% (w/w), respectively. In terms of color values, the L-value of dry grain, a-value of wet (grain, flour), and b-value of dry sample (grain, flour) were found to be the highest. Assessment of various factors and cultivars characteristics of the raw grains are of importance in the development of rice beverage.

PURPOSES : Recently, bonded concrete overlay has been used as an alternative solution in concrete pavement rehabilitation since its material properties are similar to those of the existing concrete pavements. Deteriorated concrete pavements need rapid rehabilitation in order to prevent traffic jams on Korean expressways. Moreover, speedy and effective repair methods are required. Therefore, the use of bonded concrete overlay with ultra-rapid hardening cement has increased in an effort to reopen promptly the expressways in Korea. However, mobile mixer is required for ultra-rapid hardening cement concrete mixing in the construction site. The use of mobile mixer causes various disadvantages aforementioned such as limitation of the construction supply, open-air storage of mixing materials, increase in construction cost, and etc. In this study, therefore, hydration accelerator in-situ mixing on polymer modified concrete produced in concrete plant is attempted in order to avoid the disadvantages of existing bonded concrete overlay method using ultra-rapid hardening cement. METHODS: Bonded concrete overlay materials using ultra-rapid hardening cement should be meet all the requirements including structural characteristics, compatibility, durability for field application. Therefore, This study aimed to evaluate the application of hydration accelerator in-situ mixing on polymer modified concrete by evaluating structural characteristics, compatibility, durability and economic efficiency for bonded concrete overlay. RESULTS : Test results of structural characteristics showed that the compressive, flexural strength and bond strength were exceed 21MPa, 3.15MPa and 1.4MPa, respectively, which are the target strengths of four hours age for the purpose of prompt traffic reopening. In addition, tests of compatibility, such as drying shrinkage, coefficient of thermal expansion and modulus of elasticity, and durability (chloride ions penetration resistance, freezing-thawing resistance, scaling resistance, abrasion resistance and crack resistance), showed that the hydration accelerator in-situ mixing on polymer modified concrete were satisfied the required criteria. CONCLUSIONS: It was known that the hydration accelerator in-situ mixing on polymer modified concrete overlay method was applicable for bonded concrete overlay and was a good alternative method to substitute the existing bonded concrete overlay method since structural characteristics, compatibility, durability were satisfied the criteria and its economic efficiency was excellent compare to the existing bonded concrete overlay methods.

Spawn is pure culture of vegetative mycelium and has an important to play as the inoculum or seed in cultivating mushrooms. Different grains are used as spawn in button mushroom Agaricus bisporus. Various cereal grains, such as wheat, millet, barley, sorghum, brown rice, rye, oat were assessed to compare their suitability for production of button mushroom spawn. The mycelial growth rates, density, and the number of completed grains were measured from the twentieth day of inoculation. Wheat grains showed fastest mycelial growth with 8.4 cm followed by rye, oat, barley with 8.2, 7.5 and 7.3 cm, respectively. However, they were not significantly different at the 0.05 level. In the mycelial density, foxtail millet, barley, and sorghum were best compared with that of wheat grains. Especially, the number of grains which were completely colonized by mycelia were greatest in foxtail millet with 5,123 grains followed by proso millet, and wheat with 3,052 and 914, respectively. Based on the results obtained, barley, foxtail millet, and sorghum grains would be most appropriate for grain spawn production substituting wheat grain in button mushroom.

본 연구에서는 보리의 취반 적성과 관능성 개선을 위하여 수침처리 및 적외선 가열조건의 영향을 검토하였다. 보리의 수분흡수도는 적외선가열 단독처리 또는 수침과 적외선가열의 병행처리 모두에서 크게 증가하였으며, 취반 후보리의 연화도 또한 증가하였다. 또한 이들 시료를 백미와 혼합하여 취반 후 관능성을 평가한 결과, 식감의 개선에의한 보리의 전체 기호도가 대조구 보다 크게 개선되는 것을 확인하였다. 또한 수침과 적외선가열을 병행 처리하였을 때 적외선가열 단독처리보다 우수한 관능특성을 갖는것으로 조사되어, 보리의 취반성과 관능성 개선을 위한 최적조건은 15분간 상온수침 후 120oC에서 초기 수분함량까지 가열로 설정하였다.

Roll milled- and nano-powders were prepared from the freeze dried fruiting bodies of Hericium erinaceum and their hydration properties such as water solubility index, swelling capacity, water holding capacity, and water sorption isotherm were compared. Water content in freeze dried Nano-powder of Hericium erinaceum fruiting body was 8.17%. Nano-powder has higher water solubility index compared to roll mill powder by 58.41% and 39.06%, respectively. In the same way, swelling capacity of nano-powder was 10.21ml/g where as roll mill powder has only 4.42ml/g. In contrast, water holding capacity of nano-powder (3.87g/g) is lower than that of roll mill powder (6.81g/g). Water sorption isotherm of these powders was compared and the result shows no big difference at low relative humidity (below75%). However, a high relative humidity above 75%, these two kinds of powder showed comparable difference. At 84.34% relative humidity, roll mill powder has 30.41% of moisture content compared with 47.64% of nano-powder, and at the relative humidity of 97.3%, the moisture content of roll mill and nano-powder are 37.64% and 91.06% respectively.

We have produced, characterized and compared different colloidal vehicles based on nanoemulsions. We also have investigated morphology and droplet distribution by means of electron microscope and photon correlation spectroscopy. Nanoemulsion systems characterized by different method on formulations have been obtained. Hydration power has been studied by means of a corneometer, measuring the skin electrical capacitance before and after the application of various type of skin lotions. It has been demonstrated that nanoemulsion with oil or fatty alcohol displayed a pronounced hydration power with respect to the solubilization system. In order to compare the smoothness of the skin after using skin lotion, we have measured the friction force. The skin lotions produced by nanoemulsion technique show improved smoothness of an atopic skin.

본 연구에서는 콘크리트지하차도 시공 시 수화열에 의한 열응력 분포 특성을 분석하여 시공 재료와 시공 과정에 따른 균열 발생 여부를 분석하여 설계 시에 균열을 억제할 수 있는 재료 특성과 시공 단계를 제시하는 방법에 대하여 연구하였다. 이러한 분석을 위해 열전달 이론을 도입하여 지하차도의 3차원 유한요소해석 모델을 개발하여 구조해석을 수행하였다. 1회 타설하는 콘크리트 부재의 부피가 지나치게 크면 매스콘크리트가 되기 때문에 수화열에 의한 균열이 발생하기 쉬우며 이러한 균열을 억제할 수 있는 방법으로는 크게 시공 단계를 적절하게 배치하는 것과 또는 이러한 균열을 방지 할 수 있도록 재료 특성을 바꾸어 시공하는 것으로 구분할 수 있다. 따라서 본 연구에서는 이를 위해 콘크리트 재료 성질의 시간에 따른 변화 특성 시멘트 종류 및 첨가제 유무에 따른 수화열 발생 특성, 시공 단계에 따른 구조물의 크기, 외부 환경조건 등을 고려하여 분석을 수행하였다.

저방사성폐수지, 제올라이트, 가연성잡고체 혼합폐기물을 유리화하기 위해서 AG8W1 후보 유리와 가연성잡고체 단독으로 유리화하기 위하여 DG-2 후보유리가 개발되었다. 두 후보유리의 화학적 내구성을 평가하기 위하여 PCT와 VHT 침출시험이 수행되었다. 7일 PCT 침출시험 수행결과 AG8W1과 DG-2의 주요 원소별 침출률은 기준유리(benchmark glass SRL-EA) 보다 낮게 나타남을 알 수 있었고 미국 Hanford 유리고화체 규제치 보다 낮은 결과를 나타냄을 알 수 있었다. 또한, 120일 동안의 시험에서도 주요 원소인 B, Na, Si, Li가 SRL-EA 보다 낮게 나타남을 볼 수 있었다. VHT 침출시험 수행결과 AG8W1, DG-2의 침출률(leach rate)은 각각 , 로써 미국 Hanford 규제치 보다 낮은 결과를 나타냈다. 결과적으로 유리화 시설 상용운전 시 사용예정인 이들 후보유리들의 침출은 안정화되어 있었으며 화학적 내구성이 우수함을 알 수 있었다.

본 연구는 최근 친환경 대체 시멘트로 주목받고 있는 칼슘설포알루미네이트(calcium sulfoaluminate, CSA) 시멘트의 수화 반응을 탐구한다. 배합수 및 석고의 첨가량에 따른 페이스트 배합실험을 하였으며, X-선 회절(X-ray diffraction, XRD)실험을 통해 각 변수 및 재령 일에 따른 광물 상(mineralogical phase)을 정량분석하였다. 클링커 광물의 정량분석 결과를 입력 값으로 깁스 에너지(Gibbs energy) 최소화 계산을 통한 CSA 시멘트의 수화반응 모형을 도출하였다. 배합수의 증가는 CSA 시멘트의 수화반응을 촉진 및 향상하는 것으로 조사되었으며, 석고 첨가량 증가에 따라 CSA 시멘트의 완전 수화를 위한 최소 요구 배합 수량이 증가하는 것으로 조사되었다.

스트론튬계 상전이물질은 특정한 온도에서 물질의 상태가 변함에 따라서 열을 흡수하거나 방출하게 된다. 본 연구의 목적은 스트론튬계 상전이물질의 혼입이 플라이애시 치환 모르타르 및 고로슬래그 치환 모르타르의 수화발열 및 역학적 특성에 미치는 영향을 실험적으로 평가하는 것이다. 스트론튬계 상전이물질의 혼입량은 결합재 질량의 1, 2, 3, 4, 5%로 하였다. 총 12개 수준의 모르타르 배합에 대해서 모르타르 흐름성능, 간이수화열온도상승, 압축 및 휨강도 실험을 각각 수행하였다. 실험결과 본 연구에서 사용한 스트론튬계 상전이물질은 모르타르의 수화열 저감 및 수화지연에 효과적인 것으로 판단된다. 특히 플라이애시 치환 모르타르의 최대온도 상승량은 고로슬래그 치환 모르타르의 최대온도 상승량에 비해 낮게 나타났다. 플라이애시 및 고로슬래그 치환 모르타르의 압축강도는 상전이물질 혼입량이 증가함에 따라 감소하는 것으로 나타났다.