• 한국자기학회:학술대회 개요집
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• 한국자기학회 2000년도 International Symposium on Magnetics The 2000 Fall Conference
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• pp.393-394
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• 2000

The magnetic alloy of $Nd_{2}Fe_{14}B$-type was synthesized by a mechano-chemical method, including the processes of spray-drying, de-binding, milling, $H_{2}$- and Ca-reduction and washing. The very fine $Nd_{2}Fe_{14}B$ particles smaller than $1\mu\textrm{m}$ could be achieved without the inevitable pulverization step in conventional processes.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.525-528
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• 2008

고에너지 소비형인 시멘트의 대체 재료로써 고로슬래그의 활용성을 높이기 위해 분쇄 방법과 입자의 분말도 그리고 알칼리 자극제의 종류에 따른 50wt.%의 고로슬래그를 치환한 고로 슬래그 시멘트의 수화 및 물리적 특성을 조사하였다. 알칼리 자극제로써 Ca(OH)$_2$, NaOH, Na$_2$SO$_4$,사용하였고 이런 특성들을 비교하기 위해 자극제를 넣지 않은 무첨가 슬래그 시멘트를 함께 실험하였다. 압축강도 실험에서의 분쇄방법에 차이로는 알칼리 자극제에 관계없이 롤러밀로 분쇄한 슬래그가 대체적으로 높은 강도를 나타내었으며 자극제에 따라서는 재령 7일 이내의 초기강도에서는 분말도와 분쇄방법에 관계없이 Na$_2$SO$_4$>Ca(OH)$_2$>None>NaOH 순으로 나왔으며 28일의 장기강도에선 Ca(OH)$_2$가 가장 높게 나타났다.

• 한국임상약학회지
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• 제31권2호
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• pp.96-103
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• 2021

Background: The number of elderly people with comorbidities who experience dysphagia associated with geriatric disorders, such as stroke, Parkinson's disease, and Alzheimer's dementia, is increasing. Consequently, the demand for long-term prescriptions of powdered medications is expected to rise. Most patients procure repackaged prescription medications from pharmacies; however, the guidelines regarding their expiration dates are unclear. Objectives: The aim of this study was to assess awareness among adults regarding the expiration dates and drug stability issues associated with repackaged prescription medications, including powdered medications. Methods: A questionnaire with 16 components was designed and distributed online (August 1-September 1, 2019) to adults aged 19 years or older. Statistical analyses, including descriptive analysis and chi-square test, were conducted on the obtained data. A p-value <0.05 was considered significant. Results: Data from 254 respondents were analyzed; 191 (75.20%) respondents worked in non-healthcare-related fields. A significant number of healthcare workers recognized the stability issues associated with powdered medications (p<0.001). However, a large proportion of healthcare workers were not aware of the expiration dates (p>0.05). Conclusions: More than half of the total respondents, including healthcare workers, were not familiar with the appropriate expiration dates of repackaged prescription medications. The establishment of evidence-based guidelines regarding drug expiration dates and the dissemination of awareness among patients are required. Furthermore, clinical practices including repackaging or pulverizing medications for long-term prescriptions should be avoided owing to the associated drug stability issues.

• 한국포장학회지
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• 제28권1호
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• pp.23-30
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• 2022

본 연구에서는 바이오매스 부산물을 바이오 플라스틱에 첨가할 수 있는지 여부를 찾고자 바이오매스 부산물인 왕겨, 옥 피, 밀박, 대두박에 대해 일반성분을 조사하였다. 그리고 왕겨에 대해 분체화, 표면 개질 특성을 조사하였다. 부산물 중에서는 왕겨의 입도가 6.44 ㎛로 가장 적합하였으며, silane 처리 후 ESO(Epoxidiz soybean oil)와 3-aminopropyl triethoxysilane를 1:1로 혼합한 용액을 2% 첨가 시 표면개질 상태가 가장 우수하였고, SEM에 의한 입자형상도 가장 좋은 것으로 나타났다. 따라서 ACM(air classifying mill) 처리한 왕겨를 silane 처리한 후 혼합용액을 2% 첨가하는 것이 표면이 개질된 바이오플라스틱 원료로 첨가하여 사용할 수 있을 것으로 사료되었다.

• Journal of Ginseng Research
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• 제32권3호
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• pp.179-186
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• 2008

홍삼의 분말화가 홍삼성분의 추출에 어떠한 영향을 미치는지를 알아보기 위하여 기존의 홍삼동체로부터 유용성분을 추출하는 방법과 홍삼을 분말화하여 추출하는 방법을 비교 시험하였다. 서로 다른 입도분포를 가지는 3종의 홍삼분말 ($10{\sim}40$, $40{\sim}100$, 100 mesh 이상)을 제조한 후 원형홍삼 및 홍삼분말을 이용하여 48시간 추출실험을 한 결과 입도의 크기가 가장 큰 $10{\sim}40$ mesh 홍삼분말이 가장 높은 추출수율을 나타내었다. 특히 짧은 추출시간 (12시간)대에서 원형홍삼과 비교하여 큰 수율차이를 보였다. 홍삼의 분말화가 일반적인 연속추출방법에 미치는 영향을 조사하기 위하여 3차의 용매변경 연속추출방법(1차 추출: $70^{\circ}C$ 에탄올 12시간, 2차 추출: $70^{\circ}C$ 에탄올 12시간, 3차 추출: $70^{\circ}C$ 열수 12시간)을 이용하여 추출을 수행한 결과 3차 추출까지 끝낸 상태에서의 고형분 추출수율은 $10{\sim}40$ mesh 홍삼분말이 36.2%로서 원형삼의 29.9%에 비해 약 20% 이상의 수율 증가를 보이는 것을 확인할 수 있었다. 홍삼분말 추출물내의 유용성분 분석결과 조사포닌, 총사포닌 모두 $10{\sim}40$ mesh 홍삼분말에서 추출수율이 가장 높은 것을 확인할 수 있었다. 특히 조사포닌의 경우 $10{\sim}40$ mesh 홍삼분말 추출물의 수율이 2.6%로서 원형삼 추출물의 1.77%보다 약 47% 높은 것을 확인할 수 있었다. HPLC를 이용한 사포닌 조성분석결과 모든 홍삼분말 추출물들이 비슷한 사포닌 조성을 나타낸 것으로 미루어 보아 분말화에 의한 사포닌 조성 변성은 일어나지 않은 것으로 판단되었다. 홍삼내의 다른 유용성분인 산성다당체의 경우에는 기존 원형홍삼에 비해 분말화된 홍삼들의 추출수율이 높아졌으며 가장 미세 분쇄된 100 mesh 이상의 홍삼분말에서 2.9%의 추출수율을 보여 원형삼 추출액의 1.37%에 비해 2배이상 높은 추출수율을 나타내었다. 본 결과는 추출공정에 분말화된 홍삼을 이용할 경우 추출시간의 단축 및 홍삼성분의 추출효율을 높일 수 있음을 시사하는 것으로 판단되었다.

• ALGAE
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• 제19권2호
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• pp.123-127
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• 2004

A more rapid and efficient method to extract RNA from Ecklonia cava Kjellman (Laminariales, Phaeophyceae) was introduced in this study. Each step of the procedure was evaluated and the optimal concentration of each chemical in the lysis solution was determined. Tissue pulverization with PVPP and β-mercaptoethanol in the lysis solution were not essential for RNA extraction of this species. The highest yield and purity of E. cava RNA were obtained by the lysis solution containing 1% CTAB, 1 M NaCl, 0.7% PVP, 10mM EDTA and 100mM Tris-Cl (pH 9.0). Approximately 8μg of RNA was obtained from 200 mg of ground tissue. The ratios of the absorbance at 260 nm and 280 nm were from 1.6 to 1.8 and those of at 230 nm and 260 nm were from 1.8 to 2.0. The extracted RNAs obtained in this study turned out to have a sufficient quality for cDNA synthesis.

• 한국포장학회지
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• 제26권1호
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• pp.25-31
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• 2020

Recently, applications of biomass-based plastics have increased according to the eco-friendly policy of the reduction of carbon dioxide emissions in domestic and foreign government. In this study, a paper plastic composite was produced by compounding polypropylene and micronized paper powder that was prepared using dry pulverization technology. Subsequently, the specimen of paper plastic was verified with mechanical properties, formability and product safety test to confirm the suitable packaging materials for food packaging. Paper plastics showed slightly lower mechanical properties than currently commercialized PP composites. However, paper plastics are valuable materials as environmentally friendly carbon-reducing material because of high biocarbon content, light weight features and applicability of existing manufacturing machines or system.

• 대한의생명과학회지
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• 제8권2호
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• pp.101-106
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• 2002

The purpose of this study was to test the capacity of automatic tablet crusher. The Automatic tablet crusher not only saved crushing time, but also removed floating fine powders that was occurred during crushing and caused allergy. The characteristics of powder produced by this crusher were as follows: First, to meet the condition as powder after pulverizing 5∼10 g tablet it took 6 to 12 seconds crushing time. But six seconds would do to get powder f3r oral administration. Second, when the quantity of medicine was measured by HPLC, powder from automatic crusher showed higher than that from pestle. HPLC chromatogram indicated that there was no change of medicine in the process of pulverization.

• 한국수소및신에너지학회논문집
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• 제7권1호
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• pp.71-79
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• 1996

Yttrium thin film, 580nm thick, was prepared by electron beam evaporation. Film was hydrogenated room temperature upto 40 bar hydrogen pressure, without any activation process. Hydrogen concentration was determined by a quartz-crystal microbalance(QCM) method. YH2.9 sample was made without any pulverization. Electrical resistance was measured by four-point DC method in the temperature range between room temperature and 30K for various hydrogen concentration, x=0 to 2.9 of YHx sample. Temperature dependent resistance of YH2.9 shows low temperature minimum at 105K, the metal-semiconductor transition at 260K, and a hystersis above 210K.

• ALGAE
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• 제22권2호
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• pp.125-129
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• 2007

Conventional methods for the isolation and purification of mRNA from Zygnema were unsuccessful because of its high amount of pigments and RNA interactive molecules. In particular, pigments were difficult to remove using conventional protocols because they interacted with RNA during pulverization of the materials. This resulted in total degeneration of RNA in two to three hours. To alleviate this problem, we developed an isolation method that utilized DEAE-cellulose resin. The pigments bound to DEAE anion exchange resin and separated from the RNA. Purified total RNA showed an yield of 50 μg per 100 mg of tissue with this method. The amplified 2nd strand cDNA was distributed 300 bp and over.