Effect of heat generation from cement hydration on mass concrete placement

Construction of a concrete dam requires large volume of concrete. Due to the small surface area-to-volume ratio, concrete dams are often subjected to high potential of thermal cracking, caused by the heat generation from cement hydration. To reduce the thermal cracking and ensure dam structure safety, a concrete dam is often constructed with low heat-generating cement and separated blocks having relative thin lift thickness. In Korea, low heat Type IV has been mainly used to reduce the temperature rise. Although benefits of using supplementary cementitious materials (SCMs) in concrete have been recognized, the practice of SCMs in dam concrete is not very common due to a concern for safety. On the other hand, increasing lift thickness of concrete blocks to accelerate dam construction has always been a demand. The purpose of this research is to explore the potential use of fly ash as Type IV cement replacement in Korea concrete dams and to determine the proper lift thickness of concrete blocks in dam construction. In the present study, the chemical compositions and fineness of cement and fly ash are characterized. The heat hydration of fly ash replacement for Type I cement and Type IV cement are studied and compared. The temperature distributions and thermal cracks of a concrete block having four different lift thicknesses (1.5m, 2m, 2.5m, 3m) are analyzed using FEM commercial software ANSYS. The results indicate that 40% fly ash replacement for Type I cement shows a similar heat generation and compressive strength at 28 days with that of Type IV cement and also has cost savings of 25%. A lift thickness equal or less than 1.5m showed little potential for thermal cracking. Construction placement with a lift thickness greater than 2m had high probability of thermal cracking

Temperament and Character Profiles of Sasang Typology in an Adult Clinical Sample

The purpose of this study was to examine the biopsychological personality profiles of traditional Korean Sasang typology based on the Temperament and Character Inventory (TCI) in a Korean adult clinical sample. A total of 97 adults completed the Korean version of the TCI. The participants were classified as one of three traditional Korean Sasang types (31 So-Yang, 41 Tae-Eum, 25 So-Eum) by three specialists in Sasang typology. The seven dimensions of TCI were compared between the different Sasang types using analysis of variance (ANOVA) and profile analysis. There were no significant differences in age, gender and education across the Sasang types. The TCI profile for each of the Sasang types was significantly different (profile analysis, df = 5.038, F = 3.546, P = .004). There were significant differences in the temperament dimensions of Novelty Seeking (F = 3.43, P = .036) and Harm Avoidance (F = 5.43, P = .006) among the Sasang types. The Novelty Seeking score of the So-Yang type (31.90 ± 9.87) was higher than that of the So-Eum type (25.24 ± 9.21; P = .019) while the So-Eum type (44.64 ± 8.47) scored higher on the Harm Avoidance score compared to the So-Yang type (35.16 ± 11.50; P = .003). There were no significant differences in the temperament dimension of Reward Dependence and Persistence, and the three character dimensions of Self-Directedness, Cooperativeness and Self-Transcendence. Results demonstrated distinct temperament traits associated with traditional Korean Sasang types using an objective biopsychological personality inventory. With further study, the Sasang typology may lead to enhanced clinical safety and efficacy as part of personalized medicine with traditional medicine

Deep Eutectic Solvent Pretreatment of Transgenic Biomass With Increased C6C1 Lignin Monomers.

The complex and heterogeneous polyphenolic structure of lignin confers recalcitrance to plant cell walls and challenges biomass processing for agroindustrial applications. Recently, significant efforts have been made to alter lignin composition to overcome its inherent intractability. In this work, to overcome technical difficulties related to biomass recalcitrance, we report an integrated strategy combining biomass genetic engineering with a pretreatment using a bio-derived deep eutectic solvent (DES). In particular, we employed biomass from an Arabidopsis line that expressed a bacterial hydroxycinnamoyl-CoA hydratase-lyase (HCHL) in lignifying tissues, which results in the accumulation of unusual C6C1 lignin monomers and a slight decrease in lignin molecular weight. The transgenic biomass was pretreated with renewable DES that can be synthesized from lignin-derived phenols. Biomass from the HCHL plant line containing C6C1 monomers showed increased pretreatment efficiency and released more fermentable sugars up to 34% compared to WT biomass. The enhanced biomass saccharification of the HCHL line is likely due to a reduction of lignin recalcitrance caused by the overproduction of C6C1 aromatics that act as degree of polymerization (DP) reducers and higher chemical reactivity of lignin structures with such C6C1 aromatics. Overall, our findings demonstrate that strategic plant genetic engineering, along with renewable DES pretreatment, could enable the development of sustainable biorefinery

Assessment of Animal Palatability for Domestic Developed Italian Ryegrass \u3cem\u3eLolium multiflorum\u3c/em\u3e Lam. in South Korea

About 5.6 million tons of forage were consumed in ruminant animals in Korea. But, most of them were supplied in rice straw (2 million ton) and more than one million ton of forage was imported from oversea. As a matter of fact, the self-sufficiency rate of high quality forage was 44 % (2.5 million ton). The research institute had started breeding programs of forage varieties (orchardgrass, Tall fescue and Italian ryegrass), Their remarkable breeding program resulted in release of a synthetic species Italian ryegrass (Lolium multiflorum Lam.) which was more cold-tolerant, much higher yielding than introduced varieties and more adapted in paddy field. Most varieties had focused in evaluation of chemical analysis and productivities of dry matter, however assessment of palatability for ruminant was not conducted. For this reason, this report examines the assessment of animal palatability for domestic developed Italian ryegrass in Korea

Suppression of magnetic ordering in XXZ-type antiferromagnetic monolayer NiPS3

How a certain ground state of complex physical systems emerges, especially in two-dimensional materials, is a fundamental question in condensed-matter physics. A particularly interesting case is systems belonging to the class of XY Hamiltonian where the magnetic order parameter of conventional nature is unstable in two-dimensional materials leading to a Berezinskii-Kosterlitz-Thouless transition. Here, we report how the XXZ-type antiferromagnetic order of a magnetic van der Waals material, NiPS3, behaves upon reducing the thickness and ultimately becomes unstable in the monolayer limit. Our experimental data are consistent with the findings based on renormalization group theory that at low temperatures a two-dimensional XXZ system behaves like a two-dimensional XY one, which cannot have a long-range order at finite temperatures. This work provides experimental examination of the XY magnetism in the atomically thin limit and opens new opportunities of exploiting these fundamental theorems of magnetism using magnetic van der Waals materials.Comment: 57 pages, 24 figures (including Supplementary Information

カンコク ヘナム グン ノ ベイサク ノウカ ニ オケル キコウ ヘンドウ ノ ニンシキ ニ カンスル ブンセキ

本研究では韓国ヘナム郡の米作農家における気候変動の認識に関して分析した。ロジットモデルとプロビットモデルを用いて、気候変動の認識の決定要素を検定した。結果として、米作農家の気候変動の認識は高いこと(83.6%)が示された。年齢については負の値であり、高齢者であるほど認識が少ない。つまり若年層が強く気候変動を認識していた。教育については正の値であり、高学歴であるほど強く気候変動を認識していた。そして気候情報の入手については正の値であり、情報アクセスを改善することによって、強く気候変動を認識させることができると分かった。本研究から気候変動情報、教育、訓練における適切な政策プログラムが提供される。This study analyzes perception to climate change of rice farmers in Haenam district, Korea. A logit model and a probit model are used to examine the determinants of perception to climate change. The results indicate that rice farmers\u27 perception of climate change appear to be high(83.6 percent). The findings indicate that age, education and access to climate information have a significant impact on perception to climate change. This study provides some appropriate policy program of information on climate change, education and training