• Computers and Concrete
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• 제20권3호
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• pp.283-290
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• 2017

The aim of this study is to investigate the effect of the bond strength of self-compacting mortars (SCMS) produced from ground pumice powder (GPP) as a mineral additive. In this scope, six series of mortars including control mix were prepared that consist of 7%, 12%, 17%, 22% and 27% of ground pumice powder by weight of cement. A total of 54 specimens of $40{\times}40{\times}160mm$ were produced and cured at the age of 3, 28 and 90-day for compressive and tensile strength tests and 18 specimens of $150{\times}150{\times}150mm$ mortar were prepared and cured at 28 days for bond strength tests. Flexural tensile strength and compressive strength of $40{\times}40{\times}160mm$ specimens were measured at the curing age of 7, 28 and 90-day. Mini V-funnel flow time and mini slump flow diameter tests were also conducted to obtain rheological properties. As a result of the study, it was observed that the SCMs containing 12% of GPP has the highest bond strength as compared to control and GPP mortars. Compressive strength slightly increased up to 12% of GPP.

• 한국식품영양과학회지
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• 제28권1호
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• pp.140-144
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• 1999

지충이(Sargassum thunbergii)와 우뭇가사리(Gelidium amansii) 분말을 1~5%씩 첨가하여 hambuger patty를 제조하여 물리화학적, 관능적 특성을 비교.검토하였다 L, a, b 값은 해조 분말 첨가 비율에 따라 유의적인 차이를 나타내였다(p<0.05). Patty의 수분함량은 지충이 분말첨가비율에 따라 유의적인 차이가 없었고, 우뭇가사리 분말첨가 patty는 대조군보다 수분함량이 다소 증가하였다. Cooking yield는 해조 분말 첨가 비율이 증가함에 따라높게 나타났고, 유의적인 차이가 있었다(p<0.05). 해조 분말 첨가 patty의 무기질은 Na, Ca, Mg, Fe, Zn의 순으로 함량이 높게 나타났다. 관능검사 결과 우뭇가사리 분말 3% 첨가군이 색, 종합적인 맛에서 대조군과 유사한 정수를 얻었다.

• 한국토양비료학회지
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• 제41권4호
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• pp.239-246
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• 2008

제올라이트는 높은 양이온교환능력(CEC)으로 인해 토양개량제의 사용이 고려되어 왔으나, 이에 관한 연구들의 대부분이 제올라이트를 합성하거나 천연제올라이트의 CEC를 증가시키는데 국한되어왔다. 실제로 제올라이트를 토양개량제로 사용하기 위해서는 유실되는 것을 방지하기 위한 과립화 (granulation or pelletizing)가 요구된다. 본 연구는 제올라이트를 토양개량제로 활용하기 위해 이를 포함하는 소성점토의 과립 (calcined clay granule)을 제조하고, 제올라이트의 특성을 최대로 활용할 수 있는 과립의 제조조건을 찾으려 하였다. 천연제올라이트, 고령토, 규석을 재료로 하여, pan granulator와 high shear mixer granulator의 두가지 과립기를 사용하여 과립을 제조하였다. 재료의 혼합비와 과립기의 회전속도 등을 조절하여 과립을 제조하였으며, 이를 $400\sim700^{\circ}C$범위에서 $100^{\circ}C$단위로 소성한 후 파쇄강도 (crushing strength), 기공분포 (pore distribution), CEC를 측정하였다. 토양개량제로 사용할 과립은 취급시에 요구되는 기본적인 강도뿐만 아니라 토양과 혼합된 후 답압(踏壓)에 견디기 위한 강도 또한 요구된다. 본 연구에서는 과립의 답압에 관한 저항성 평가방법을 마련하고, 마른 상태와 젖은 상태에서 과립의 저항성을 측정하였다. 과립기의 회전속도와 가열온도에 비례하여 답압에 대한 저항성은 증가하나 CEC는 감소하였다. Pan granulator는 $700^{\circ}C$이하의 가열에서 적절한 강도를 갖는 과립을 제조할 수 없었으나, high shear mixer granulator는 $500^{\circ}C$이상의 가열에 의해 답압에 저항성을 갖는 과립을 제조할 수 있었다.

• Journal of Periodontal and Implant Science
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• 제30권3호
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• pp.527-538
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• 2000

Several extraction cases with advanced bone loss as a result of periodontal disease, root or labial bone fracture, extensive caries, and periapical lesions occur esthetic, functional problems and severe bone loss. Therefore, to treat these cases used several surgical methods and socket preservation among this therapies have been evaluated simple, effective and good prognosis in the implant placement. Socket preservation therapy have been used with barrier membranes or/and graft materials. Deproteinized bovine bone mineral have been evaluated ideal grafting materials. Recently, calcium-phosphate thin film coated bovine bone powders were developed in our country, but the study for these material wasn't reported. When two types of xenograft materials were implanted in extraction sockets of Beagle dogs, the effects of these were analyzed after 4 weeks and 8 weeks histological views. The results of this study were as follows. 1. In control groups, 4 weeks after implantation, the extraction sockets were filled with connective tissue which has dilated vessels and epithelial growth. And after 8 weeks, irregular connective bundles were observed. But new bone formation was not seen. 2. In Bio-Oss groups, epithelial growth was not seen and bone powder was covered with connective tissue fiber. New bone formation was found around the interproximal bone. There was no special change seen after 8 weeks, connective tissue fibers became more regular, and bone growth near bone powder was not made well. 3. In Ca-P BBP groups, epithelial cells didn't grow in the extraction sockets, there was a lot of new bone made around the bone powder after 8 weeks, new bone around bone powder was replaced with mature bone. It is thought that bone powder grafting into the extraction sockets is very useful for conservation of ridge, and Ca-P BBP is more effective in bone formation than Bio-Oss.

• 한국식품영양학회지
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• 제20권1호
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• pp.40-46
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• 2007

본 연구는 건강지향적인 식품 소재로서 기능성과 효능을 지닌 동충하초를 이용하여 먹기 편한 젤리를 제조하기 위해 동충하초 분말을 각각 0%, 0.5%, 1%, 1.5%, 2% 첨가하여 만든 동충하초 젤리의 일반성분, 무기질 함량, 색도, 물성 및 관능평가를 실시한 결과는 다음과 같다. 동충하초 젤리의 일반성분 함량에서 수분 함량과 조단백질 함량은 동충하초 분말을 첨가한 군에서 높게 나타났으며(p<0.05), 반면에 조지방 함량은 대조군이 가장 높고 동충하초 분말 첨가군이 낮게 나타났다. 무기질 함량은 동충하초 분말을 첨가한 군이 대조군보다 칼슘, 마그네슘 및 칼륨 함량이 높았다(p<0.05). 색도 검사에서 L값과 a값은 대조군에 비해 동충하초 분말을 첨가한 군에서 낮아지는 경향이었으며 b값은 대조군이 가장 낮게 나타났다. 조직감은 대조군에 비해 동충하초 분말을 첨가한 군에서의 Hardness, Gumminess 및 Chewiness가 낮아지는 경향이었다. 관능검사에서는 동충하초 분말 1% 첨가군에서의 색, 맛, 질감 및 전체적인 기호가 높게 평가되었다. 이상의 연구결과를 통해 건강지향적인 기능성 식품 소재로서 기호성과 이용성을 증대시킬 수 있는 동충하초 젤리의 동충하초 분말 첨가량은 1% 첨가군이었으며 겔화제와 같은 첨가물에 따른 동충하초 젤리의 관능평가에 대한 연구가 지속적으로 이루어져야 된다고 사료된다.

• 디지털콘텐츠학회 논문지
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• 제14권1호
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• pp.35-40
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• 2013

연마재와 Coolant를 이용한 슬러리는 그동안 반도체 웨이퍼를 시작으로 태양광 산업의 Wire Saw에서 사용량이 급격히 증가하였다. 이에 본 논문에서는 슬러리를 분리 정제하여, 수세뿐만 아니라 화학적 처리를 통하여 보다 고순도의 실리콘카바이드 분말을 얻어, 마이크로웨이브 건조방식으로 건조하였다. 건조한 슬러리 벌크를 분쇄하고 화학적 처리까지 수행하여 제작한 Powder를 각각 열분석, 입도분석, SEM 촬영, 성분분석, XRF, XRD을 통하여 분석하였다. 본 연구 결과 화학적 처리를 통하여 얻은 Powder의 회수율이 수세 처리를 통하여 얻은 Powder 보다 더 높아지는 것을 알 수 있었다. 태양광 소재 산업에서 발생하는 다량의 슬러리를 통합, 재활용함으로 점차 강화되고 있는 국내외 환경 규제에 적극 대응하고, 관련 소재 산업의 인프라 구축 효과를 기대할 수 있다.

• Advances in concrete construction
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• 제5권1호
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• pp.65-74
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• 2017

This study was focused on the use of partial replacement of cement with glass powder in high strength concrete and also copper slag as a partial replacement of coarse sand in concrete. The high strength concrete was prepared with different mineral admixtures like silica fume, fly ash and rice ash husk in different proportions. An experimental investigation has been carried to study about the effect of glass powder on high strength copper slag concrete. The range of glass powder was 10%, 15% and 20% as a replacement of cement. The range of copper slag was 0%, 20%, 40% and 60% as a replacement of natural sand. In addition to the different percentage of fly ash, silica fume, and rice husk ash 5% and 10% was also studied in copper slag concrete. Thus, a total of 51 cubes were casted and compressive strength test was performed on them. The result of the study shows that the value of average compressive strength of concrete after addition of 10%, 15% and 20% of glass powder are 70.47, 72.01 and 73.31 respectively. The value of average compressive strength after addition of 20%, 40% and 60% copper slag as a replacement of sand are 72.18, 74.38 and 73.08 respectively. The value of average compressive strength after addition of 5% and 10% fly ash as a replacement of cement are 71.56 and 73.22. The value of average compressive strength after addition of 5% and 10% silica fume as a replacement of cement are 72.33 and 73.53. The value of average compressive strength after addition of 5% and 10% rice husk ash as a replacement of cement are 72.86 and 69.49. At the level of 20% replacement of cement by glass powder meets maximum strength as compared to that of controlled concrete and copper slag high strength concrete.

• Human Ecology Research
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• 제62권2호
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• pp.327-336
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• 2024

This study was investigated to examine the antioxidant activity and quality characteristics of ginger Jocheong added with Gujeung-gupo ginger powder and the results were as follows. As the amount of Gujeung-gupo ginger powder added into ginger Jocheong increased, the moisture and carbohydrate contents of ginger Jocheong significantly decreased(F=133.33, p<.001) and increased(F=36.15, p<.001), respectively. The content of mineral composition such as K, Ca and Zn showed higher values as the amount of added Gujeung-gupo ginger powder increased. As the amount of Gujeung-gupo ginger powder added into ginger Jocheong increased, sweetness(F=200.00, p<.001), viscosity(F=441.23, p<.001), L value(F=1,458, p<.001), a value(F=44.56, p<.001) and b value(F=203, p<.001) decreased significantly, and pH significantly increased(F=59.18, p<.001). As the amount of Gujeung-gupo ginger powder added into ginger Jocheong increased, total polyphenol content(F=86.015, p<.001), total flavonoid content(F=885.012, p<.001), and DPPH radical scavenging activity(F=75.136, p<.001), ABTS radical scavenging ability(F=145.751, p<.001), and FRAP activity(F=172.242, p<.001) increased. From the above results, the antioxidant activity and quality characteristics of ginger Jocheong added with Gujeung-gupo ginger powder confirmed the potential development of ginger Jocheong with high antioxidant activity.

• 대한의생명과학회지
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• 제11권3호
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• pp.275-279
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• 2005

High-salted mineral water (Daehan Deep Water, Korea) that is pumped up from below the sedimentary rock layer of Dadaepo, Busan, Korea has a composition similar with that of deep sea water. Under the well-being boom, the mineral water is processed for various uses including washing or oral administration. However, high concentrations of various minerals in the mineral water are suspected to affect on the physiology of human body, especially on blood pressure (BP). Here, we examined the effect of Hot Mineral(R), dried powder of the mineral water, on the change of BP. Sprague­Dawley rats were grouped and orally administered $2.5\%$ Hot Mineral(R) (group M), $2.5\%$ NaCl (group S) or normal water (group C). Excreted urine was collected in metabolic cage for 24 hours. The systolic blood pressure (SBP) of the group S was remarkably increased (P<0.005) compared with that of the group M and the group C, which showed little changes of the SBP during 2 weeks. While average daily sodium intake were 0.32 mg in the group C, 6.64 mg in the group M and 4.07 mg in the group S, average daily sodium excretion were 11.37 mg, 53.70 mg and 7.75 mg, respectively. These results indicate that the sodium excretion in the group M was much higher than the other two groups. In this study, we suppose that the plenty amount of minerals such as calcium, potassium and magnesium in Hot Mineral? have an effect not to increase the SBP and to prompt sodium excretion out of the body. Therefore, these results suggest that oral administration of appropriate amount of Hot Mineral(R) for limited period does not induce increased SBP.

• 자원리싸이클링
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• 제20권4호
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• pp.36-45
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• 2011

금속분말을 환원제로 사용하는 시멘테이션에 의하여 자동차 폐촉매의 침출액과 침출잔사의 세척액으로부터 백금족 금속을 환원 석출시켜 회수하는 연구를 수행하였다. 환원제로 사용한 알루미늄, 마그네슘 그리고 아연이 백금족 금속의 시멘테이션에 미치는 영향을 조사하였으며 알루미늄을 최적 환원제로 선정하였다. 침출액에 19.3 당량의 알루미늄을 첨가하고 $50{\sim}60^{\circ}C$에서 10분간 시멘테이션을 행하였을 때 백금, 팔라듐, 로듐의 환원석출율은 각각 99.3%, 99.4%, 90.2% 정도 이었다. 또한 세척액에 알루미늄을 45 당량 투입한 후 시멘터이션 반응을 통해 백금, 팔라륨, 로듐을 각각 97%, 97%, 90% 회수할 수 있었다. 그리고 회수한 환원석출물의 금속불순물들을 질산침출로 제거함으로써 백금족 금속의 품위를 약 10% 정도 향상시킬 수 있었다.