• Resources Recycling
• /
• v.30 no.6
• /
• pp.19-27
• /
• 2021

Electrically conductive mortar used in industrial carbon material byproducts was manufactured and analyzed in this study. The contents of the carbon material and mixed water were controlled, and the distance between electrodes was set to 0.42 m and 0.88 m. The carbon material was graphite with a layered structure. The carbon material was used as fine powder and aggregate substitutes according to particle size. The average particle sizes of each materials were 18.4㎛ and 546.1 ㎛ and the electrical conductivities were 62.3 S/m and 32.5 S/m, respectively. To maintain similar mortar flow in each sample, the water content was increased with increasing carbon material, and accordingly, the porosity showed an increasing trend. When electrode distance of the mortar (week 6) was 0.42 m, the voltage-current values were 342 V-1.48 A (S20) and 349 V-1.44 A (S30). For electrode distance of 0.88 m, these values were 513 V-0.98 A (S20) and 500 V-1.01 A (S30). The exothermic properties improved with increasing carbon material content and decreasing electrode distance.

• Korean Chemical Engineering Research
• /
• v.57 no.1
• /
• pp.17-21
• /
• 2019

The redox flow battery (RFB) is a large-capacity energy storage equipment, and the vanadium redox flow cell is a typical RFB, but VRFB is expensive. Iron-chrome RFBs are economical because they use low-cost active materials, but their low performance is an urgent problem. One of the reasons for the low performance is the crossover of the active materials. In this study, the sulfonated Poly (ether ether ketone) (sPEEK) membrane, which is a hydrocarbon membrane, was used instead of the fluorine membrane to reduce the crossover of the active materials. The chromium ion permeability of the sPEEK membrane was $1.8{\times}10^{-6}cm^2/min$, which was about 1/33 of that of the Nafion membrane. Thus, it was shown that the use of the sPEEK membrane instead of the fluorine membrane could solve the high active material crossover problem. The activation energy of iron diffusion through the sPEEK membrane was 24.9 kJ/mol, which was about 66% of Nafion membrane. And that the e-PTFE support in the polymer membrane reduces the active material crossover through Iron-Chrome Redox Flow Battery (ICRFB).

• Applied Chemistry for Engineering
• /
• v.30 no.3
• /
• pp.358-364
• /
• 2019

To improve the optical characteristics and antifouling of anti-reflective coating (AR) films, various AR coating films were prepared by varying the mixing ratio of tetraethylorthosilicate (TEOS)/base and methyltrimethoxysilane (MTMS)/acid hybrid solution. Prepared AR coating films were characterized by UV-Vis spectroscopy, contact angle analyzer, atomic force microscope (AFM), FT-IR and pencil scratch hardness test. In an AR coating film that prepared from the hybrid solution with a 10 wt% MTMS/acid solution, the glass substrate showed an excellent optical property (97.2% transmittance), good antifouling ($121^{\circ}$ water contact angle and $90^{\circ}\;CH_2I_2$ contact angle) and moderate mechanical strength (pencil hardness of 4 H). In particular, it is considered that the good antifouling was due to the well dispersion of the methyl group ($-CH_3$), derived from a small amount of MTMS/acid solution in the hybrid solution, on the substrate surface. From results of the pencil hardness test, the mechanical strength of AR coating film was improved as the content of MTMS/acid solution increased.

• Resources Recycling
• /
• v.30 no.5
• /
• pp.10-16
• /
• 2021

In this study, a clinker was prepared using raw materials with CaCl₂. The characteristics of the chlorine-added clinker and cement were analyzed. The clinker modulus were set to Lime Saturation Factor (LSF) 92, Silica modulus (SM) 2.5, and Iron Modulus (IM) 1.5. The physical properties of cement using the chlorine-containing clinker were characterized. As the chlorine content increased, the free-CaO content in the clinker decreased, and that in the 2000 ppm clinker was reduced by approximately 40% compared to that in the 0 ppm clinker. There was an increase in the amount of chlormayenite, with a content of up to 3.4% present in the 2000 ppm clinker. The amounts of alite and belite also slightly increased. The compressive strength of mortar at 3 days and 7 days increased as the chlorine content increased. This trend was presumed to arise from the effect of hydration, which was promoted by the presence of chlorine. The compressive strength of 1000 ppm mortar increased by approximately 20% compared to that of 0 ppm mortar.

• The Journal of Internal Korean Medicine
• /
• v.41 no.6
• /
• pp.1245-1254
• /
• 2020

Introduction: The aim of this study was to report the effect of Korean medicine treatments on a stroke patient with acute cerebral infarction. Method: A 63-year-old male with anterior and middle cerebral artery infarction had symptoms of dizziness and disorientation. The patient was treated with Korean medicine therapy, including the herbal medicine "Sunghyuangjunggi-san-gamibang." Treatment progress was assessed using the Korean version of the Modified Barthel Index (K-MBI) and the Korean dizziness handicap inventory (K-DHI). Results: After 14 days of treatment, the K-DHI score decreased from 78 to 7 and the K-MBI score increased from 18 to 24. The patient's main symptoms were improved after the treatment, and no side effects were observed. Conclusion: Korean medicine treatment, including Sunghyuangjunggi-san, might be a recommended therapeutic option for dizziness and disorientation in stroke patients.

• The Korean Journal of Food And Nutrition
• /
• v.35 no.6
• /
• pp.491-498
• /
• 2022

This study compared the antioxidant and mineral properties of the leaves and seeds of fifteen Korean adzuki bean (Vigna angularisL.) breeding lines. This study was conducted in an attempt to expand the use of Korean adzuki bean leaves. The potassium, calcium, magnesium, and sodium contents of the leaves were significantly higher than the seeds, in particularly, the potassium content. The leaves had approximately 3.3 times higher potassium content than the seeds. For instance, the potassium content of YA1317 leaves was 21% higher than that of Arari. The total polyphenol content and ABTS activity of Adzuki bean leaves were significantly higher than the seeds, as opposed to the total flavonoid content and DPPH scavenging activity. Among the 15 breeding lines, YA1402 had 1.2~3.2 times higher antioxidant content and activity as compared to the Arari variety. It was concluded that adzuki bean leaves had higher mineral content, antioxidant component and activity as compared to the seeds. Therefore, adzuki bean leaves could be used an ingredient for dishes and as a medicine.

• Resources Recycling
• /
• v.31 no.3
• /
• pp.53-60
• /
• 2022

The physical properties of chlorine-containing cement were analyzed to optimize the operational conditions when waste resources containing chlorine were used in the cement manufacturing process. Cement with clinker to gypsum weight ratios of 95:5 and 93:7 were manufactured. In addition, the iron modulus (IM) of clinker was set to 1.3, 1.5, and 1.7 to evaluate the burnability and physical properties of clinker. With constant chlorine content, increasing gypsum content resulted in a decrease in the 3 day-compressive strength, whereas the 28 day-compressive strength increased. In addition, flow and setting time also increased with increasing gypsum content. As the IM decreased, burnability was improved, free-CaO content decreased, alite and ferrite content increased, and compressive strength increased In particular, the compressive strength of IM 1.3 was approximately 14% greater than that of IM 1.7.

• Journal of Life Science
• /
• v.32 no.12
• /
• pp.989-996
• /
• 2022

Some flowers have high sensual appealability due to their unique shapes, colors, smells, and tastes. Such edible flowers receive social attention as a noble ingredient of functional teas. In this study, methanol extracts of 23 commercial flower teas (CFTs) were prepared, and their color differences were compared. No tar color pigments were detected in the 23 CFT. The average content of total polyphenol of the 23 CFTs was 80.2±50.92 mg/g and the extracts of jin-dal-rae (Rhododendron mucronulatum Turcz), mae-hwa (Prunus mume), mae-mil (Fagopyrum esculentum), mok-ryun (Magnolia kobus), and sal-gu (Prunus armeniaca var. ansu Maxim) flowers showed total polyphenol contents greater than 150 mg/g. The average content of total sugar of the 23 CFTs was 187.4±166.5 mg/g and the extracts of chamomile (Chamaemelum nobile), kuk-hwa (Chrysanthemum morifolium), dong-baek (Camellia japonica L.), and won-chu-ri (Hemerocallis fulva) flowers showed total sugar contents greater than 400 mg/g. Among the 23 CFTs, the extract of jang-mi (Rosa hybrida hortorum) flower has prominent anti-thrombosis activity, and the extracts of dal-ma-ji (Oenothera lamarckiana), dong-baek, hibiscus (Hibiscus syriacus), and mae-mil flowers showed strong inhibitions against thrombin and blood coagulation factors. Also, the extracts of jang-mi, kum-jan-hwa (Tagetes erecta L.), mae-mil, mok-ryun dong-baek, and jin-dal-rae flower showed strong radical scavenging activities against DPPH, ABTS, and nitrite and reducing power. Our results suggest that the flowers of jang-mi, mae-mil, and dong-baek can be developed as promising anti-thrombosis treatments.

• Applied Chemistry for Engineering
• /
• v.33 no.2
• /
• pp.202-209
• /
• 2022

Effects of the support and amount of NiCl₂ on ammonia adsorption capacity were investigated to improve the ammonia adsorption performance. NiCl₂ was impregnated onto the surface of various supports under ultrasonic irradiation. The physicochemical properties and ammonia adsorption performance of NiCl₂-impregnated adsorbents were investigated. Among the various supports, it was found that the adsorption capacity of ammonia was the best when NiCl₂ was impregnated on activated carbon (AC) with the highest specific surface area. As a result of changing the amount of NiCl₂ impregnated on AC, the NiCl₂(2.0)/AC adsorbent impregnated with 2 mmol·g^-1 of NiCl₂ showed the highest ammonia adsorption capacity of 5.977 mmol·g^-1. In addition, the adsorption capacity was found to be maintained at an almost constant level in five repeated cycle tests under the condition that low-temperature heat could be utilized. This indicates that the adsorbent has excellent regeneration ability.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.42 no.6
• /
• pp.783-789
• /
• 1997

This study was conducted to identify leakage of fluorescent substances out of 56 crops and to develop sorting methods of nonviable seeds of Chinese cabbage. Fluorescent substances were detected from 36 species, Chinese cabbage, radish, broccoli, cauliflower, egg plant and rape seed etc. In Chinese cabbage, the germination rate of non-sorted seeds decreased rapidly with ageing of seeds at 45$^{\circ}C$ and 100％. After Chinese cabbage seeds soaked for 4hrs and coated with cellulose, the sorting ratio of non fluorescent seeds were decreased 91.3％ to 1.7％ by increasing ageing periods from control to 8 days, while fluorescent seeds were increased drastically from 8.7％ to 98.3％. Also, incubation of water soaked dead seeds of Chinese cabbage treated with 0.5-1.0％ ninhydrin and 0.01N sodium thiosulfate for 30~60 minutes at 35$^{\circ}C$ developed purple color.