• Journal of the Korean Chemical Society
• /
• v.31 no.1
• /
• pp.118-120
• /
• 1987

• Korean Journal of Plant Resources
• /
• v.23 no.6
• /
• pp.487-497
• /
• 2010

ROS have been associated with pathogenic processes including carcinogenesis through direct effect on DNA and play an important role in the pathogenesis of inflammation. Because of many types of phenolic acid derivatives and flavonoids, apples have been one of the human diet since ancient times and are one of the most commonly consumed fruits in worldwide. In this study, catechin, chlorogenic acid and phlorizin dihydrate were purified and identified by HPLC and GC/MS. The contents of catechin, chlorogenic acid and phlorizin dihydrate were 1.01 mg, 7.01 mg and 3.67 mg/ kg wet weight, respectively. Catechin and phlorizin dihydrate were found to significantly inhibit oxidative DNA damage, while chlorogenic did not affect. Also, catechin inhibits NO and $PGE_2$ production via suppressing iNOS and COX-2 expression. However, chlorogenic acid and phlorizin dihydrate did not affect. Our results show that catechin may be the most active phenolic compound in anti-oxidative damage and anti-inflammatory effect.

• Journal of Veterinary Clinics
• /
• v.21 no.3
• /
• pp.302-308
• /
• 2004

Sixty-six dogs diagnosed with cystolithiasis at animal clinics in the Busan area between April 2002, and April 2003, were reviewed. The chemical analysis of cystoliths from 66 dogs indicated that the predominant mineral component was struvite (45 dogs), calcium oxalate (14 dogs), or urate (6 dogs). Animals affected with struvite were grouped into four (s-1; struvite only, s-2; struvite mixed with lesser quantities of calcium oxalate or ammonium urate, s-3; nuclei and lamination, s-4; struvite nucleus surrounded by other minerals), with calcium oxalate into six(o-1; calcium oxalate monohydrate only, o-2; calcium oxalate dihydrate only, o-3; combination of calcium oxalate monohydrate and dihydrate, o-4; calcium oxalate nucleus surrounded by other minerals, o-5; 100% calcium oxalate monohydrate nucleus surrounded by 100% calcium oxalate dihydrate, o-6; mixed calcium oxalate monohydrate nucleus surrounded by mixed calcium oxalate dihydrate), and with urate into two(u-1; ammonium acid urate only, u-2; ammonium acid urate mixed with lesser quantities of other minerals). In this study, the numbers of 4 groups of struvite were (s-1; 10, s-2; 9, s-3; 21, s-4; 5), 6 groups of calcium oxalate were (o-1; 0, o-2; 1, o-3; 2, o-4; 3, o-5; 2, o-6; 6), and 2 groups of urate were (u-1; 6, u-2; 0). The data from each group was analyzed and compared. Shih Tzu(14 cases), Yorkshire terrier(10 cases), mixed-breed(10 cases) and Miniature schnauzer(7 cases) were more frequently affected than the other breeds. Females(40 cases) were affected more than males(26 cases). Twenty-nine dogs had cystoliths associated with a bacterial urinary tract infection, and uroliths tended to recur. We conclude eradication of urinary infection along with appropriate food (e.g. prescription diet) with client compliance should help in reducing the incidence or severity of the disease.

• Journal of the Korea Institute of Building Construction
• /
• v.14 no.3
• /
• pp.252-258
• /
• 2014

With the vision of 'a low carbon green develop' various industrial by-products were used as replacement of cement, in order to reduce $CO_2$ emissions from the manufacturing process of cement. Blast furnace slag is one of the industrial by-products. Due to the similar chemical compositions to ordinary Portland cement, blast furnace slag have been widely used in concrete with minimum side effects. Hence, in recent years, alkali activated slag-based composites are extensively studied by many researchers. However, the alkali activator can cause a number of problems in practice. Therefore, in this study, an alternative way of activating the slag was investigated. To activate the slag without using an alkali activator, calcium sulfate dihydrate was chosen and mixed with natural recycled fine aggregate. Fundamental properties of the slag-based mortar were tested to evaluate the effect of calcium sulfate dihydrate.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.40
• /
• pp.19.1-19.6
• /
• 2018

Background: Calcium pyrophosphate dihydrate deposition disease (CPDD) is a rare disease in the temporomandibular joint (TMJ) space. It forms a calcified crystal mass and induces a limitation of joint movement. Case presentation: The calcified mass in our case was occupied in the left TMJ area and extended to the infratemporal and middle cranial fossa. For a complete excision of this mass, we performed a vertical ramus osteotomy and resected the mass around the mandibular condyle. The calcified mass in the infratemporal fossa was carefully excised, and the segmented mandible was anatomically repositioned. Scanning electronic microscopy (SEM)/energy-dispersive X-ray spectroscopy (EDS) microanalysis was performed to evaluate the calcified mass. The result of SEM/EDS showed that the crystal mass was completely composed of calcium pyrophosphate dihydrate. This result strongly suggested that the calcified mass was CPDD in the TMJ area. Conclusions: CPDD in the TMJ is a rare disease and is difficult to differentially diagnose from other neoplasms. A histological examination and quantitative microanalysis are required to confirm the diagnosis. In our patient, CPDD in the TMJ was successfully removed via the extracorporeal approach. SEM/EDS microanalysis was used for the differential diagnosis.

• Journal of the Korean Ceramic Society
• /
• v.52 no.1
• /
• pp.28-32
• /
• 2015

In this article, the influence of a hydrolyzed wheat protein retarder on the hydration process, ion concentration in liquid phase, degree of supersaturation, and crystal morphology of plaster was investigated. Furthermore, the retarding mechanism and the strength loss of gypsum were also studied by scanning electron microscopy (SEM). The results indicate that the use of the hydrolyzed wheat protein retarder for plaster achieved a better retarding effect and lower strength loss. The combination of gypsum plaster with the retarder not only decreased the plaster's early hydration rate and prolonged its setting time efficiently, but also militated against the crystal morphology of dihydrate gypsum. For example, the crystal dimensions changed little, but the proportion of needle-shaped crystals decreased. Combination with calcium ions on the surface of dihydrate gypsum crystal nuclei may form a chemisorbed layer, reduce the surface energy of the crystal nuclei, and inhibit the growth of the crystal nuclei of dihydrate gypsum. Consequently, the hydration process of building gypsum becomes greatly extended and is slowed down significantly.

• Advances in concrete construction
• /
• v.11 no.3
• /
• pp.183-192
• /
• 2021

Due to economic and environmental benefits, increasing the substitution ratio of ordinary cement by industry by-products like fly ash (FA) is one of the best approaches to reduce the impact of the concrete industry on the environment. However, as the substitution rate of FA increases, it will have an adverse impact on the performance of cement-based materials, so the actual substitution rate of FA is limited to around 10-30%. Therefore, in order to increase the early-age strength of high replacement (30-70%) low-calcium ultrafine FA blended cement paste, sodium sulfate and calcium sulfate dihydrate were used to improve the reactivity of FA. The results show that sodium sulfate has a significant enhancement effect on the strength of the composite pastes in the early and late ages, while calcium sulfate dihydrate has only a slight effect in the late ages. The addition of sodium sulfate in the cement-FA blended system can enhance the gain rate of non-evaporation water, and can decrease the Ca(OH)2 content. In addition, when the sulfate chemical activators are added, the ettringite content increases, and the surface of the FA is dissolved and hydrated.

• Journal of dental hygiene science
• /
• v.12 no.4
• /
• pp.320-328
• /
• 2012

The purpose of this study was to evaluate the tooth whitening and properties of an enamel surface after treatments with tooth bleaching agents that contained dicalcium phosphate dihydrate (DCPD) and hydrogen peroxide (HP). Thirty specimens were obtained from fifteen premolar and were randomly divided into three groups (n=10): 1, 3.5% HP + 0 g DCPD; 2, 3.5% HP + 0.1 g DCPD; 3. 3.5% HP + 1 g DCPD. All groups were bleached 8 hours per day for 14 days. With increasing DCPD concentration, the pH values in the agents increased, making it less acidic. However, there was no statistically significant difference (p>.05). As the concentration of DCPD was increased, the concentration of Ca and P was also increased. In all groups, after the tooth whitening, the tooth color was found to have a value of $L^*$ (p<.05). All groups showed significantly decreased enamel microhardness compared to their baseline (p<.05). The percentage microhardness loss (PML) of the group A1 and A2 were significantly lower than that of group A3. The obvious variation of morphology was observed on enamel surfaces in group A1. Following an analysis of the constituents of enamel surface after bleaching, as DCPD content was increased, the amount of Ca and P was increased. In this study, the experimental results suggest that DCPD/HP agent less demineralization changes such as the erosion morphology and hardness loss without compromising whitening efficiency.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2014.05a
• /
• pp.222-223
• /
• 2014

In this study, industrial by-products including blast furnace slag, incineration ash and waste gypsum were used with recycled fine aggregates to manufacture the zero-cement mortar.The replacement ratio of dihydrate gypsum and anhydrite gypsum was fixed as 0 and 10%, the replacement ratio fo WA1 was fixed as 0.5% and 1.0%, respectively. It could be identified that when the replacement of gypsum was 10% and WA1 of 1.0%, the strength could be in the range of normal strength.

• 제어로봇시스템학회:학술대회논문집
• /
• 1988.10b
• /
• pp.875-878
• /
• 1988

In this work it is shown how the methods used in chemical engineering for the analysis and simulation of processes may be applied to the actual phosphoric acid plant. Attention has been focused on the dihydrate process for which the necessary fundamental experimental data and plant operation data are available. The results of the simulation have shown that a reasonable description of the process at hand is possible by the proposed method. However, because of the complexity of the process, of the limited basic experimental data reported in literature, and the limitations of mathematics, the model was somewhat idealized and gave a reliable representation of the influence of only a few of the variables that affect the performance of the plant.