• 펄프종이기술
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• 제47권6호
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• pp.98-105
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• 2015

Demands of thermal recording paper have been increased significantly by increase in usage of invoice, fax, and label. Thermal recording paper was mainly made based on virgin fiber. It is necessary to find a suitable alternative to virgin fiber in terms of environment protectional resources conservation. In this paper, deinking properties of different recovered papers were analyzed in order to use the recovered paper as raw material of thermal recording paper. Recovered paper were ONP, OMG and white ledger. Flotation reject of OMG was high because inorganic pigments in coating layer could be removed by upstream of froth. Brightness of white ledger and OMG were much higher than that of ONP. Therefore, properties of pulp made from the recovered paper could be enhanced with increase in blending ratio of white ledger and OMG. However, blending ratio of OMG caused the increase of flotation reject. Consequently, the optimum blending ratio of ONP, OMG, and white ledger was 3:3:3 for eco-friendly thermal recording paper. Under the condition, brightness was about 70% and ERIC was below 300 ppm.

• 한국식품영양학회지
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• 제6권4호
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• pp.281-286
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• 1993

Strawberry pulp was separated into serum and Insoluble pulp by centrifugation. The serum was concentrated in vacuo at 55~58$^{\circ}C$ and 10% aroma recovered. Two folds concentrated strawberry pulp was prepared by mixing concentrated serum, aroma fraction and Insoluble pulp. To develop aroma-rich jam, the strawberry jam was prepared by filling mixture of concentrated pulp, sucrose, citric acid and pectin into retortable pouches and by heating them after heat-seating. The color and flavor quality of the jam prepared by new method were better than the jam prepared by conventional method, as Indicated by GC, GC/MS data, surface color and anthocyanin contents. These results were confirmed by the sensory evaluations. Flavor off-flavor, color intensity and overall acceptance were superior to the conventional method.

• 펄프종이기술
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• 제47권2호
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• pp.34-41
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• 2015

Recovered paper has been widely used as a main raw material of papermaking in Korea. Recycling of recovered paper helps to reduce production cost and preserve an environment. To recycle recovered paper efficiently, de-inking is a key process in recycling mills. De-inking process would be affected by various influencing factors such as the type of de-inking agent, mixed ratio of recovered paper, season, and process conditions. In this study, fatty acid and nonionic surfactant were used as the de-inking agent in froth-flotation process of mixed recovered paper. De-inking properties of mixed recovered paper were investigated according to the addition level of each chemical. Nonionic surfactant had a small effect on de-inking efficiency of mixed recovered paper due to decreased reject. As the additional level of fatty acid increases, fragmented ink particles increased and then optical properties of recycled paper decreased because fragmented ink particles adsorbed onto the fiber surface.

• 자원리싸이클링
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• 제24권5호
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• pp.22-32
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• 2015

본 연구는 폐기저귀 재활용 공정 이후 회수되는 재생 자원의 가치를 높여 경제성을 확보하기 위한 관점에서 업사이클링 개념을 논의하고, 벤치마킹을 통해 펄프와 혼합 플라스틱의 업사이클링 방안을 수립하고자 하였다. 업사이클링은 원래의 물질이 다시 사용될 때 품질이 향상되고 폐기물을 질적 환경적으로 더 높은 가치를 가진 새로운 물질이나 제품으로 전환하는 과정으로 요약되며, 다양한 사례를 통해 용도를 다 한 제품이더라도 새로운 가치를 갖게 된다는 것을 알게 되었다. 그러나 기존의 업사이클링 사례들은 정성적인 디자인 요소를 통한 가치 창출이므로 정량적인 전략의 도출이 어렵고 업사이클링 완제품 시장 경쟁력에 대한 판단이 불확실하다. 따라서 본 연구에서는 활용성 차원에서 B2B 제품까지 범위를 확장하고, 재생펄프와 혼합 플라스틱 두 소재를 같이 활용할 수 있도록 업사이클링 방향성을 설정하여 이를 만족할 수 있는 제품군에 대해 분석하였다. 그 결과, 셀룰로오스 단열재로의 적용을 제안하며, 향후 국내/외 단열재 시장에서 고성능 셀룰로오스 비중이 약 3배 이상 급성장 할 것으로 예측되기 때문에 본 시장을 목표로 업사이클링 전략을 세워야 할 것으로 보인다.

• 펄프종이기술
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• 제48권3호
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• pp.14-22
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• 2016

Pulping is a stage that can change fibrous raw materials into pumpable slurry. Recovered paper can be defibrated to individual fibers by shear stress generated by rotation of a rotor and water. Disintegration of recovered paper is more complicated than that of chemical pulp. When disintegration of recovered paper is poor, screening and cleaning efficiency will be worse and properties of paper will also be deteriorated. Therefore, pulping is an important treatment for improvement of availability of recovered paper and process runnability. In this study, degrees of disintegration of KOCC obtained from a linerboard mill was analyzed with a pilot-scale screen. Flake removal of KOCC slurry was performed by a pilot screen. Simple pumping action gave a positive effect on disintegration of KOCC. After pumping for 10 minutes, paper strength increased without the change of water retention value and fibrillation of KOCC slurry. This phenomena can be explained by modification of hornified surface of KOCC fibers by shear stress generated by pumping. Consequently, disintegration efficiency of KOCC can be enhanced by control of retention time at pulper or an agitation power at chests of papermaking process.

• 대한치과교정학회지
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• 제21권3호
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• pp.635-656
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• 1991

It was the aim of this investigation to evaluate some histologic aspect of rat pulp tissue after it had been compromised by an experimental orthodontic force. Experimental animals of thirty five Spraque-Dawley rats were employed. The first upper molars had been successively mesial moved (initial load 100 gr.) with a closed coil spring during 21 days. The experimental periods were set on immediate, 1 day, 1 week, 2 weeks, 3 weeks, 4 weeks following retention time. On each experimental period, the rats were killed and prepared for the light microscopy. After prepared with H/E stain and Gomori's one-step trichrome stain, the specimens were analyzed with evaluation criteria which were adopted in this study. The result may be summarized as follows; 1. The main pulp changes due to experimental orthodontic force included vacuolization of odontoblastic layer, circulation disturbance, root resorption, reduced pulp collagenous fiber density and mean cell count of pulp fibroblast in the immediate group. 2. The pulp tissue changes were revealed reversible because the relieved pulp tissues from experimental orthodontic force were recovered rapidly in each evaluation criteria during retention periods. 3. Compared with normal control group, pulp collagenous fiber density were decreased in immediated group (p < 0.01), but increased in each retention groups. These seem to suggest that the pulp tissues were aged after experimental orthodontic force conditions. 4. Compared with normal control group, mean cell counts of pulp fibroblasts were decreased in immediate group (p < 0.05), but increased continuous in each retention groups. These seem to indicate that the pulp tissues were highly regenerative after experimental orthodontic force conditions. 5. Compared with normal control group, root resorptions occurred in all immediate specimens (p < 0.01) and they were healed in each retention periods, but often observed in 4 weeks retention group. These seem to indicate that root resorptions were recovered slowly after experimental orthodontic force conditions.

• Restorative Dentistry and Endodontics
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• 제12권2호
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• pp.101-108
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• 1987

The purpose of this study was to investigate the pulpal responses of dental adhesive resins. A total of 40 cavities of the permanent healthy teeth from 4 dogs were prepared. In the experimental group, the cavities were etched for 1 minute with citric acid and filled with experimental resins (ie. Super-Bond C & B$^{(R)}$). In the control group, the cavities were filled with calcium hydroxide base materials (ie. Dycal$^{(R)}$) without etching. The dogs were sacrificed at one, two, three and four weeks after the time of filling and the specimens were routinely prepared and stained with Hematoxylin-Eosin. The microscopic findings were as follows: Infiltration of inflammatory cells was not observed in both experimental and control groups. Change in the odontoblastic layer was not observed in all control groups but severe swelling was observed in deep dental pulp tissue of the control two and three week cases. Pulp tissue was recovered with plenty of fibrous component in the control four week case and reparative dentin formation was not occurred in all cases. Slight changes of the odontoblastic layer beneath the cavity were observed in the experimental one week case. In experimental two and three week cases, swelling of deep pulp tissue was increased and localized reparative dentin formation was observed. In the experimental four week case, odontoblastic layer was recovered with regular appearance and fibrous component of the pulp was increased, but reparative dentin formation was not evident.

• 펄프종이기술
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• 제39권5호
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• pp.58-63
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• 2007

This paper sums up all the different steps broached in this project : The NIR spectroscopy technique has been studied and implemented at CTP using a mobile spectrometer device and different optical materials. Methods, based on statistical data analysis (in particular PLS regressions), have been investigated. A laboratory "prototype" using these techniques and methods has been developed in order to control the recovered papers quality, in terms of humidity percentage and sample composition (paper, board, contaminants).

• 전기학회논문지
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• 제61권8호
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• pp.1204-1209
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• 2012

To diagnose dental pulp vitality, electric pulp tester has been widely used, which is a method to test condition of nerve. However, especially in the case of patients with trauma, nerve desensitization could temporarily occur even though nerve might be recovered by blood flow within the pulp later, which implies that blood flow in dental pulp is also an important factor for diagnosing vitality. This paper described the development of a probe that relatively measured blood flow in dental pulp using photoplethysmography (PPG). The probe emits four different wavelength light sources including three visible and an infrared light. We tested which light source detect sensitively the blood flow in dental pulp. As a result, green light had the largest peak to peak voltage and the power spectrum among different wavelengths.

• 동국한의학연구소논문집
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• 제2권1호
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• pp.167-176
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• 1993

The purpose of this study is to invesigate the effect of Yook-Gun-ja-Tang on the side effect of cyclophosphamide to splenical tissue in the rat. The experimental animal were divided into normal group, control group, sample group by way of method treatment of the drug. Each group was sacrificed and stained in accordance with the schedule and observed under light microscope. The results of this study were as follow : 1. After treatment of Yook-Gun-Ja-Tang, rat's weight and volume were more increased than normal group and control group. 2. The decrease of the numbers of the splenical tissue after administration of cyclophosphamide were recovered with prescription of the Yook-Gun-la-Tang ; The decreases of white pulp, red pulp, marginal zone, central artery were recovered. 3. Increased macrophages in red pulp of splenical tissue of rats with administration of cyclophosphamide were decreased after treatment of Yook-Gun-Ja-Tang. These results appeared to suggest that Yook-Gun-Ja-Tang might be effective on the: side effect of cyclophosphamide to splenical tissue of rat's and applied to the prescription for the recovery of the side effect of drug.