• 한국가구학회지
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• 제12권1호
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• pp.1-9
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• 2001

This study was carried out to elucidate the relationship between wood anatomy and the water flow path in P. koraiensis and L. leptolepis. through the experiment of penetration of the dye solution. The experiment was performed by permeating 1% acid, alkali and direct solution into the xylem just after being cut. The results obtained were summarized as follows : 1. In P. koraiensis and L. leptolepis, the dye solution penetrated into sapwood and annual rings adjacent to cambial zone were only dyed according to ascent of tree height. 2. The penetrability of latewood was better than that of earlywood. 3. In P. koraiensis and L. leptolepis, the main water flow path in longitudinal direction was the trachied and that in transverse direction was ray trachied and ray parenchyma. Also, the dye solution was found in resin canal. 4. P. koraiensis was more permeable than L. leptolepis. 5. Among the acid, alkali and direct dye solution, the acid dye solution was the most permeable.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.259-263
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• 2001

There are several steps such as slicing, lapping, chemical etching and mechanical polishing in the silicon wafer production process. The chemical etching step is necessary to remove damaged layer caused In the slicing and lapping steps. The typical etching liquor is the acid mixture comprising nitric acid, acetic acid and hydrofluoric acid. At present, the waste acid is treated by a neutralization method with a high alkali cost and balky solid residue. A solvent extraction method is applicable to separate and recover each acid. Acetic acid is first separated from the waste liquor using 2-ethlyhexyl alcohols as an extractant. Then, nitric acid is recovered using TBP(Tri-butyl phosphate) as an extractant. Finally hydrofluoric acid is separated with the TBP solvent extraction. The expected recovered acids in this process are 2㏖/l acetic acid, 6㏖/1 nitric acid and 6㏖/l hydrofluoric acid. The yields of this process are almost 100% for acetic acid and nitric acid. On the other hand, it is important to recover and reuse the metal values contained in various industrial wastes in a viewpoint of environmental preservation. Most of industrial products are made through the processes to separate impurities in raw materials, solid and liquid wastes being necessarily discharged as industrial wastes. Chemical methods such as solvent extraction, ion exchange and membrane, and physical methods such as heavy media separation, magnetic separation and electrostatic separation are considered as the methods for separation and recovery of the metal values from the wastes. Some examples of the application of solvent extraction to the treatment of wastes such as Ni-Co alloy scrap, Sm-Co alloy scrap, fly ash and flue dust, and liquid wastes such as plating solution, the rinse solution, etching solution and pickling solution are introduced.

• 분석과학
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• 제14권4호
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• pp.306-310
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• 2001

황상용액 매질에서 요오드 음이온을 흡착제에 흡착시킨 후 황산용액에 남아있는 요오드 음이온을 정량하기 위해 이온 크로마토그래피를 적용하였다. 산화제 작용을 하는 황산의 농도를 0.25 M, 0.5 M, 1 M로 변화시키고 요오드 음이온을 각각 첨가한 후 시간변화에 따라 요오드 음이온이 산화되는 정도를 측정하였다. 황산농도가 진할수록 요오드 음이온은 산화되어 휘발하므로 적게 검출되었다. 수산화나트륨 용액을 사용하여 환산매질을 중화하였다. 중화된 0.5 M $Na_2SO_4$ 매질 중 요오드 음이온의 농도범위가 0-20 mg/L인 구간에서 검정곡선의 직선성이 좋게 나타났다(r=0.99999).

• 한국임상수의학회지
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• 제28권1호
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• pp.28-32
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• 2011

This study was performed to evaluate the efficacy of 0.8% sodium hyaluronic acid solution and crosslinked hyaluronic acid mixture for the prevention of postoperative intraperitoneal adhesion in rats. Forty-five animals were divided into three groups ; 0.9% saline treated control group, 1% sodium carboxymethyl cellulose treated group (SCMC), and 0.8% sodium hyaluronic acid solution and crosslinked hyaluronic acid mixture treated group (SHCH). Adhesions were induced by suturing both the ileal serosa and peritoneum abrased until petechial bleeding occurred. Fourteen days later, adhesions were evaluated clinically and histopathologically. The mean tensile strength was significantly decreased in the SCMC and SHCH groups compared to the control group (p < 0.05), and the SHCH group had the lowest tensile strength. The distance of adhesion site was highest in the control group and significantly decreased in the SHCH group comparing control group (p < 0.05). The inflammatory cell infiltration, collagen hyperplasia and neovascularization of the SCMC and SHCH groups were significantly lower than the control group (p < 0.05). Therefore, it was concluded that the SHCH may be useful to prevent postoperative intraperitoneal adhesion in rats.

• Asian-Australasian Journal of Animal Sciences
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• 제16권12호
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• pp.1743-1748
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• 2003

The effect of pH on the fermentation characteristics and the formation of cis-9, trans-11 conjugated linoleic acid (CLA) and trans-11 octadecenoic acid by mixed ruminal bacteria was examined in vitro when incubated with linseed or rapeseed. Concentrate (1%, w/v) with ground linseed (0.6%, w/v) or rapeseed (0.5%, w/v) was added to 600 ml mixed solution of strained rumen fluid with artificial saliva (1:1, v/v), and was incubated anaerobically for 12 h at $39^{\circ}C$. The pH of culture solution was maintained at level close to 4.5, 5.3, 6.1 and 6.9 with 30% $H_2SO_4$ or 30% NaOH solution. pH increment resulted in increases of ammonia and total volatile fatty acid (VFA) concentration in culture solutions containing both oilseeds. Fermentation did not proceeded at pH 4.5. Molar proportion of acetate decreased but that of propionate increased as pH increased when incubated with oilseeds. While the hydrogenating process was very slow at the pH range of 4.5 to 5.3, rapid hydrogenation was found from the culture solutions of pH 6.1 and 6.9 when incubated with linseed or rapeseed. As pH in culture solution of linseed or rapeseed increases proportions of oleic acid (cis-9 $C_{18:1}$) and trans-11 octadecenoic acid increased but those of linoleic acid and linolenic acid decreased. The CLA proportion increased with pH in culture solution containing rapeseed but CLA was mostly not detected from the incubation of linseed.

• Food Science and Biotechnology
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• 제17권4호
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• pp.883-887
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• 2008

The purpose of this study was to develop a new preparation process for chemical transformation of ginseng saponin glycosides to prosapogenins. Ginseng and ginseng extracts were processed under several treatment conditions using ascorbic acid solution. Treating with ascorbic acid at pH 2-3 and above $80^{\circ}C$ increased the ginsenoside $Rg_3$ content of samples to over 3% as compared to other pH levels and temperatures. In addition, ginseng and ginseng extracts that were processed under a high ascorbic acid solution treatment condition (pH 2.0, 5 hr) contained more ginsenoside $Rg_3$ (approximately 16 times) than those processed under a low ascorbic acid solution treatment condition (pH 3.0, 5 hr). The highest quantity of ginsenoside $Rg_3$ (3.434%) occurred when a sample of fine ginseng root extract (AG2-9) was processed with the ascorbic acid solution at pH 2.0 for 9 hr. However, there was no change in the amount of ginsenoside $Rg_3$ when fine ginseng root extracts were processed with ascorbic acid solution at pH 2.0 for over 9 hr. In conclusion, the results indicated that ascorbic acid treatment of ginseng extracts can produce a level of ginsenoside $Rg_3$ that is over 90-fold the amount found in commercial red ginseng.

• Journal of Nutrition and Health
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• 제7권1호
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• pp.37-43
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• 1974

Ascorbic acid수용액에 조미료 및 향신료를 단독독 또는 배합 첨가(添加)하였을 때의 ascorbic acid의 함량(含量)을 2,4 Dnitrophenylhydrazine method에 의하여 정량(定量)하였다. 조미료 및 향신료를 단독으로 ascorbic acid 수용액에 첨가(添加)하였을 때의 total ascorbic acid의 잔재율(殘存率)은 식초, 설탕, 소금, 미원, 파, 마늘, 깨, 엿, 간장, 고추, 고추장, 후추, 생강, 계피등이 ascorbic acid단독만의 수용액보다 높은치(値)를 나타냈으며 실백, 참기름, 된장의 첨가(添加)는 적은치(値)를 나타냈다. 또한 ascorbic acid의 자동산화율(自動酸化率)은 회향, 계피, 생강, 후추, 된장, 실백, 카레등이 가장 높은치(値)를 나타냈으며 마늘, 참기름, 미원, 설탕, 꿀, 소금, 새우젓, 고추장, 간장등이 대체적으로 얕은치(値)를 나타냈다. 또한 배합(配合)조미료에 있어서는 모두 ascorbic acid의 함량(含量)은 높은치(値)를 나타냈으며 콩나물, 무나물, 무침등 가장 빈용되는 조미료 배합(配合)인 No. 8,9,10이 높은 치(値)를 나타냈으며 겨자채의 조미료배합이 제일 적은치(値)를 나타냈다.

• 한국재료학회지
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• 제22권9호
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• pp.465-469
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• 2012

This paper focuses on the after synthesis of CdTe quantum dots(QDs) in aqueous solution. CdTe nanoparticles were prepared in aqueous solution using mercaptocarboxylic acid or thioglycolic acid(TGA) as stabilizing agents. QDs emit light smaller than the nano size. The contents of the mercaptocarboxylic acid, and a kind of raw material, were revealed for a period of time. We succeeded in synthesizing a very high quality QDs solution; we discussed how to make QDs better and to keep them stabilized. TGA is known as one of the best stabilizing agents. Many papers have mentioned that TGA is a good stabilizing agent. We dramatically confirmed the state of QDs after the experiments. The QDs solution can be influenced by several factors. Different content of TGA can influence the stability of the CdTe solution. Most papers deal with the synthesis of CdTe, so we decided to discuss the after synthesis process for the stability of the CdTe solution.

• 한국식품영양과학회지
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• 제32권6호
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• pp.806-811
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• 2003

크랜베리 수용액의 색상 안정성 에 대한 pH, 열, 광, 당, 유기산, 금속이온, 비타민 C, $B_1$, $B_3$ 및 $B_{6}$의 영향을 조사하였다. 크랜베리 수용액의 색상은pH가 낮을수록 농색화 효과가 높았고 pH가 높아질수록 최대흡수파장이 장파장 쪽으로 이동하는 bathochromic shift현상이 관찰되었다. 열의 영향에 대한 실험 결과, 색상의 반감기가 37$^{\circ}C$에서 34일, 9$0^{\circ}C$에서 91분, 12$0^{\circ}C$에서 29분으로 온도가 높을수록 색상의 반감기가 급격하게 짧아졌다. 광에 의해 색상의 안정성이 크게 저하되었는데, 형광보다 일광에 대한 영향이 더 컸으며 저장 시 광을 차단함으로써 안정성을 증진시킬 수 있었다. 당류 첨가는 오히려 무첨가구에 비해서 저장 안정성을 저하시켰고 fructose가 색상 저하를 가장 촉진하는 것으로 나타났다. 유기산 중 fumaric acid, citric acid, malic acid, acetic acid 순으로 색상 안정성에 효과가 있었으며 특히 fumaric acid는 색상안정화에 크게 기여하였다. 금속이온 중 $Na^{+}$과 $Mg^{2+}$은 색상안정화에 기여하였으나 $Mn^{2+}$은 색상의 안정성을 가장 크게 저하시켰고 다음으로 F $e^{2+}$, $K^{+}$, $Ca^{2+}$순으로 저하시켰다. 비타민 C와 $B_1$은 크랜베리 수용액 색상의 안정성을 저하시켰으며 특히 비타민 C는 색상의 안정성을 크게 저하시켰다. 반면 $B_3$, $B_{6}$는 색상의 안정성에 미약하게 기여하였다.

• 동아시아식생활학회지
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• 제6권2호
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• pp.187-194
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• 1996

닭고기를 멸균 증류수, 5% potassium sorbate, 5% sodium acid pyrophosphate, 2.5% potassium sorbate와 2.5% sodium acid pyrophosphate 혼합용액으로 처리하여 4$^{\circ}C$에서 보관하면서 미생물 수의 변화, pH 변화, TBA 값의 변화를 측정하였다. Potassium sorbate와 sodium acid pyrophosphate 혼합용액의 처리는 중온성 균과 저온성 균의 성장억제에 대한 상승효과를 주었고, 장내 세균의 성장억제에도 효과적이었다. 효모와 곰팡이의 성장억제에는 potassium sorbate의 처리가 가장 효과적이었다. Potassium sorbate와 sodium acidpyrophosphate 혼합용액 과 potassium sorbate 처리는 닭고기의 저온성 균과 장내 세균의 유도기를 연장시켰다. 닭고기의 pH는 저장기간 중 높아졌으며, 이것이 항미생물 효과의 감소에 영향을 주었을 것으로 추정되었다. TBA 값은 sodium acid pyrophosphate처리시 가장 낮게 나타나 지방함량이 많은 식품에 사용될 경우 항미생물 효과뿐만 아니라 항산화효과도 함께 줄 수 있을 것으로 기대되었다.