• Restorative Dentistry and Endodontics
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• v.45 no.4
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• pp.50.1-50.11
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• 2020

Objectives: In this study, we investigated the potential of amoxicillin-loaded polymeric microspheres to be delivered to tooth root infection sites via a bioactive reparative cement. Materials and Methods: Amoxicillin-loaded microspheres were synthesized by a spray-dray method and incorporated at 2.5% and 5% into a mineral trioxide aggregate cement clinically used to induce a mineralized barrier at the root tip of young permanent teeth with incomplete root development and necrotic pulp. The formulations were modified in liquid:powder ratios and in composition by the microspheres. The optimized formulations were evaluated in vitro for physical and mechanical eligibility. The morphology of microspheres was observed under scanning electron microscopy. Results: The optimized cement formulation containing microspheres at 5% exhibited a delayed-release response and maintained its fundamental functional properties. When mixed with amoxicillin-loaded microspheres, the setting times of both test materials significantly increased. The diametral tensile strength of cement containing microspheres at 5% was similar to control. However, phytic acid had no effect on this outcome (p > 0.05). When mixed with modified liquid:powder ratio, the setting time was significantly longer than that original liquid:powder ratio (p < 0.05). Conclusions: Lack of optimal concentrations of antibiotics at anatomical sites of the dental tissues is a hallmark of recurrent endodontic infections. Therefore, targeting the controlled release of broad-spectrum antibiotics may improve the therapeutic outcomes of current treatments. Overall, these results indicate that the carry of amoxicillin by microspheres could provide an alternative strategy for the local delivery of antibiotics for the management of tooth infections.

• Journal of the Korean Ceramic Society
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• v.49 no.5
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• pp.454-460
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• 2012

The nano-sized zirconia powders were synthesized in an impregnation method using pulp and $ZrOCl_2{\cdot}8H_2O$ as an initial material. The synthesized powders were characterized by XRD and FE-SEM. The particle size of the powder was controlled by preparation conditions, such as drying temperature and time. As a result of the various drying and calcination conditions, 30~50 nm sized homogeneous zirconia particles were obtained at $800^{\circ}C$ for 1 h. Crystallization and the rapid growth of particles were accelerated with increasing calcination temperature and time. Tetragonal phase generated below $800^{\circ}C$ were transferred to monoclinic phase with increasing calcination temperature and time. Moreover, above $800^{\circ}C$, heat treatment time had very large influence on the particle growth, and the change of drying condition also had large influence on the growth of a crystal.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.5
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• pp.98-103
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• 2015

The reduction of the energy consumption in papermaking process become more important issue because of the regulation of green house gas (GHG) emission. Since more than half of energy for papermaking process is consumed during drying process, the increase of the drying efficiency would be very important solution for saving energy and reduction of GHG emission. The improvement of drying efficiency could be very difficult for the liner board mill because the liner board are usually made of recycled paper, OCC (old corrugated container). The short fiber and fines originated the OCC lead to compact sheet structure and delay the water flow out during wet pressing process and drying process. The application of lignocellulose spacer could provide more loose wet sheet structure and result in the higher drainage rate and the improved drying efficiency. In this study, the effects of the application of lignocellulose spacer to the liner board mill were evaluated based on the mill trial. In order to overcome the common disadvantage of the spacer, the loss of strength properties, the spacer was pretreated with amphoteric polyelectrolyte during mill trial. The results showed the application of pretreated spacer improved the drying efficiency by reducing steam consumption. And the loss in the strength properties by the spacer could be supplemented by the pretreatment.

• The Journal of the Convergence on Culture Technology
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• v.9 no.3
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• pp.593-599
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• 2023

Nickel oxide (NiO) nanoparticles were successfully synthesized by a simple liquid phase process for producing ceramics powder using a precursor impregnated with a nickel(II) nitrate hexahydrate aqueous solution in an industrial pulp. The microfibrile structure of the precursor impregnated with nickel nitrate hexahydrate aqueous solution was confirmed by scanning electron microscope (SEM), and the crystal structure and particle size of nickel oxide (NiO) particles produced as the heat treatment temperature of the precursor were analyzed by X-ray diffraction (XRD) and SEM. As a result, it was confirmed through XRD and SEM analysis that the temperature at which the organic material of the precursor is completely thermally decomposed was 495-500℃, and the size and crystallinity of the nickel oxide particles produced increased as the heat treatment temperature increased. The size of the nickel oxide particles obtained by heat treatment at 500-800℃ for 1 hour was 50-200 nm. It was confirmed by XRD and SEM analysis that a NiO crystal phase was formed at a heat treatment temperature of 380℃, only a single NiO phase existed until 800℃.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.4
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• pp.96-101
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• 2015

In the previous study, we investigated the physical properties of new organic fillers made from major agricultural byproducts, including rice husks, peanut husks and garlic stems, and we estimated that rice husk was the best candidate for use as new organic fillers in paperboard. In this study, an organic filler prototype was produced with rice husk and the mill trials were carried out in a white liner chipboard (duplexboard) mill. The rice husk organic filler was added to the middle ply of SC $350g/m^2$ to determine the optimal conditions for the manufacture of rice husk organic fillers. The mill trials were performed three times and the bulk improvement and drying energy reduction were measured to identify the functionality of the rice husk organic filler compared to that of the commercial wood powder. In the first mill trial, the test failed because the surface roughness of the duplexboard had deteriorated after the rice husk organic filler was added to the OCC stock. As all of the particles remaining on the 60 mesh sieves were removed and the particle size was decreased by increasing the length of the grinding process, the surface roughness of the duplexboard did not be deteriorated in the second mill trial. However, the bulk improvement and drying energy reduction were not observed. In the final mill trial, as the particle size of the rice husk organic filler was controlled by increasing the portion of particles passing through the 60 mesh sieves and remaining 100 mesh sieves, higher bulk improvement and drying energy reduction were acquired compared to the commercial wood powder.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.1 s.119
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• pp.38-47
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• 2007

This study was carried out to develop a new application field and obtain the basic data of citrus peel as waste in Jeju island and traditional Hanji for producing functional Hanji. The results measuring physical and optical properties, water vapor permeance and antibacterial activity are as follows. It was revealed that apparent density go as down but bulk raise up in the structural view of Hanji with increasing of the addition various Korean citrus peel (citrus unshiu, cheonggyun and hanrabong peel, and citrus unshiu peel powder) percentages, and that the density of Hanji added citrus unshiu peel was higher, but bulk was lower in compared with Hanji added other kinds of peel. Those Hanji added citrus unshiu peel, cheonggyun peel, hanrabong peel and citrus unshiu powder were very great not only in the strength (breaking length, burst index, tear index and folding endurance) but also in water vapor permeant rate in comparison with Hanji. The pHs of Hanji were neutrality (7 to 8). The brightness of the Hanji added various citrus peel percentages was low in compared to Hanji, and the 40% addition of hanrabong peel was the lowest. When 40% hanrabong peel was added to Hanji, it was very yellow in the color degree. When cheonggyun peel was added to Hanji manufacture, water vapor permeant rate was highly effective. It is known that vacant space of intrafiber was reduced by image analysis of Hanji and the additions of peel of citrus unshiu, cheonggyun and hanrabong were distributed equally in the interior of Hanji. The antibacterial activity of Hanji added citrus unshiu peel is more than 98%. After all, it would be able to increase utilization of Hanji, extensively. Namely, production of high quality Hanji added functional materials is expected for new valuable industry of citrus peel and Hanji.

• Resources Recycling
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• v.31 no.4
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• pp.40-48
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• 2022

In waste lithium iron phosphate (LFP) batteries, the cathode material contains approximately 4% lithium. Recycling the constituent elements of batteries is important for resource circulation and for mitigating the environmental pollution. Li contained in the waste LFP cathode powder was selectively leached using persulfate-based oxidizing agents, such as sodium persulfate, potassium persulfate, and ammonium persulfate. Leaching efficiency and waste LFP powder properties were compared and analyzed. Pulp density was used as a variable during leaching, which was performed for 3 h under each condition. The leaching efficiency was calculated using the inductively coupled plasma (ICP) analysis of the leachate. All types of persulfate-based oxidizing agents used in this study showed a Li leaching efficiency over 92%. In particular, when leaching was performed using (NH₄)₂S₂O₈, the highest Li leaching percentage of 93.3% was observed, under the conditions of 50 g/L pulp density and an oxidizing agent concentration of 1.1 molar ratio.

• Resources Recycling
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• v.3 no.3
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• pp.32-49
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• 1994

Hydration process is one of the basic carbonation system. Limestone sludge produced in Pohang Iron & Steel Co., Ltd. We tested for identify of hydration characteristics. The result obtained in this study can be summarized as follows; 1. The classify of limestone sludge is type of ground calcium carbonate(-3mm+325mesh)and the major mineral of calcite, and further more high grade(CaO 51%), fine powder(15~22$\mu\textrm{m}$). 2. Limestone sludge mixed two process sludge, first one is washing process sludge and the other one is wet collect kiln dust. The composition rate is about 8:2. Wet collect kiln dust is major mineral of calcite, too. But the sludge is assumed to one by quick lime, slaked lime and unreacted natural limestone. So, the ideal process is dividing of the washing process sludge and wet collect kiln dust. 3. We manufactured of slaked lime from limestone sludge. To investigate the effect of hydration reactor, the experiments was done with various reactor type as magnetic stirrer, shaking incubator and ultrasonic vibration reactor, respectively. Generally, ultrasonic vibration reactor is excellent hydration for limestone sludge and produced very fine slaked lime powder with ideal distribution. 4. The optimum condition is 10% pulp density, when the manufacture of fine slaked lime powder by ultrasonic vibration reactor. And hydration times to compare the results of the study with ultrasonic vibration reactor of generalized most short time(5~10 min). 5. Finally, the dispersive characteristics of slaked lime powder measured 1~5 $\mu\textrm{m}$ from limestone sludge were compared with those of natural limestone ones(10~20$\mu\textrm{m}$), in order to check applicability of slaked lime with hydration process from limestone sludge.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.4
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• pp.377-386
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• 2006

Imwonshibyukji(1827) is an important and stupendous ancient scientific book, which is much like an encyclopedia, that can discern the dietary life of the latter period of Choseon. This article is assorted, which is mentioned in this book, as Cho(Misutkaru-in parched grain that is weed out into powder) to the main material of grain Youmicho, Wandoocho, Youcho, also the medicinal plant as the main material Youkhangcho, Backyupcho, Chungumcho, Unyoungcho, and Naecho, Haengcho, Eicho, Imgumcho, Joyou, Bokbunjacho, made by fruit. The results of inquiring the property by the assortment is as you see in the following. Youmicho, Wandoocho, Youcho, Youkhyangcho, Backyupcho, and Chungumcho, which consist of glutinous rice, nonclutinous rice, barley, buckwheat, pea, and black soybean are among 13 kinds of methods to make Cho. The manufacturing process is similar to that of Misutkaru, but in the case of Unyoungcho 6 different medicinal powders are mixed with Chundang and Sookmill to form a hard portable taffy substance, which is quite unique. Naecho, Haengcho, Eicho, Imgumcho, Joyou, and Bokbunjacho are extracted from pulp and processed in a powder form like Misutkaru, which can also be considered as a fruit tea. Youcho is unique in its sense, since it is fermented by maggots that are bred in order to obtain the juice. Cho is known to calm thirst and empty stomachs, and has various medicinal materials to act as food to aid virility. It is also known to have multiple functions as an alternative staple, refreshment to aid virility, portable food, and preferable beverage. There are ten references on Cho, 37% are Korean in Ongheejobji and 63% Chinese in Jaeminyosool, Bonchogangmok, Chungmoonbobang, Nongjungchunsuh, Wangshinongsuh, Shikgyung, Sukmyung, Bonchoseupyou, and Wisaengbogam. The citations are in the general introduction and 13 types of Cho are cited 19 times overall, but citations based on Chinese references are non existe.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2006.11a
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• pp.28-42
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• 2006

Tannins are phenolic compounds that precipitate proteins and composed of a very diverse group of oligomers and polymers. Tannins are potential biological antioxidants, which are widely believed to be an important line of defense against oxidative damage and may participate in the prevention of cancer and cardiovascular disease. Persimmon(Diospyros kaki L.) has been cultivated in East Asia and is a good source of nutritional antioxidant vitamins, carotenoids and tannins. In general persimmon peel was regarded as a waste matter, although based on recent studies, the peel contains more carotenoids and polyphenols than pulp. Several investigation conducted in experimental animals have reported that dietary persimmon fruit and peel effectively lowered the levels of plasma total cholesterol and LDL-cholesterol. We conducted experiments to investigate in vitro antioxidative activities of persimmon peel powder (PP) and its soluble tannin extract (ST) and their dietary effects on productive performances and physiological responses in poultry. The PP and ST exhibited in vitro antioxidative activity in SOD - like activity model. The yolk color and eggshell color were significantly improved by the addition of PP and ST into layer diets. The contents of total cholesterol, triacylglycerol and phospholipid of liver in the groups fed diets containing PP and ST tended to be reduce as compared with those of control. With adding of PP and ST, Haugh unit was increased after 7 and 14 days of storage. In conclusion, PP and ST can be used as valuable feed additives for reducing hepatic lipid contents without harmful effects on overall productive performances and physiological responses in laying hens.