• 한국식생활문화학회지
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• 제11권5호
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• pp.635-641
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• 1996

As a basic study for preparing pine sprout tea, chemical components in pine sprouts and pine needles were analyzed as follows: In proximate composition the contents of most components except for crude fat were different between in pine sprouts and pine needles. Moisture content in pine sprouts was higher than that in pine needles. Calcium and potassium were major minerals contained in pine sprouts and needles, and their contents in pine needles picked in December were higher than those picked in June. Soluble tannin and vitamin C contents in leaf part of pine sprouts were much higher than those in stem part and their contents in pine needles were increased according to their growth. Free sugars like fructose, glucose and sucrose were contained in both pine sprouts and needles, and their contents in pine sprouts were higher in stem part as compared that in leaf part. Although fourteen kinds of amino acids were detected in pine sprouts and pine needles, their contents were extremely low. Amino acid composition between pine sprouts and pine needles was different each other, but major amino acids contained in them were same, those are acidic amino acids such as aspartic acid and glutamic acid. Amino acid contents in pine needles were increased according to the growth. In fatty acid composition in leaf part of pine sprouts, saturated fatty acid contents were higher than unsaturated fatty acid contents, but in stem part unsaturated fatty acid contents were higher. In pine needles the amount of saturated fatty acid was increased with the growth, but the amount of unsaturated fatty acid was rather decreased.

• 접착 및 계면
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• 제20권2호
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• pp.61-65
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• 2019

본 연구에서는 인계 폴리올을 phenylphosphonic dichloride (PPDC), allylphosphonic dichloride (APDC)에 ethylene glycol (EG)을 반응시켜 합성하였고 분자량이 880~1,560 g/mol의 폴리올 얻었다. 이를 이용하여 polycarbonate diol (PCD)와 함께 4,4'-diphenylmethane diisocyanate (MDI)와 중합하여 인계 폴리우레탄을 얻었다. 합성한 인계 폴리우레탄의 인의 합량이 높아질수록 열분해 온도는 감소하였지만 챠 (char)의 발생과 발생양이 증가하는 것을 확인하였다. 또한 UL-94V 시험법을 통하여 APDC를 포함하는 인계 폴리우레탄 인의 함유량이 0.5 wt%이상일 때 V-0의 난연등급되는 것을 확인하였다.

• Elastomers and Composites
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• 제43권4호
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• pp.221-229
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• 2008

전분을 매트리스 고분자로 하여 아크릴 모노머인 2-ethylhexylacrylate와 methyl methacrylate, acrylic acid를 그래프트 중합하였다. 중합은 라디칼 유화중합에 의하여 전분의 함량을 증가시키면서 수행되었다. 효소인 $\alpha$-amylase 가 전분 대비 0.174% 투입되었을 때 가장 안정한 중합물이 얻어졌으며 전분의 함량이 증가함에 따라 중합물의 유리전이온도가 상승하였다. 전분 함량의 증가에 따라 계내의 -OH기가 많아짐에 따라 중합물의 입자 크기와 점도가 증가하였다. Peel strength는 전분 함량이 증가할수록 -OH기 증가에 의해 중합물이 피착체 표면과의 친화력 상승이 일어나서 증가하였다. 반면 초기 점착력은 전분 함량이 증가할수록 유리전이온도의 증가에 따라 필름의 경도가 증가하면서 감소하였다.

• 한국연초학회지
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• 제9권2호
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• pp.59-68
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• 1987

황색종 잎담배의 성숙과 노쇠 (이식후 50일부터 106일까지 )에 따른 생엽중 전분, 전당, 니코틴 및 전질소의 함량 변화와 이들 성분간의 관계를 조사한바, 전분함량은 두 품종 모두 각 엽위에서 성숙함에 따라 증가하였으나 노쇠함에 따라 감소하였다. 전질소 함량은 성숙함에 따라 감소하였으나 니코틴 함량 은 점점 증가하였다. 전당 함량은 성숙함에 따라 감소하는 경향이었다. 전분 함량은 전질소 함량과는 부의 상관을 보였으나 니코틴 함량과는 정의 상관이 인정되었다. 전질소 함량과 니코틴 함량은 부의 상관이 인정되었다. 그러므로 수확기를 관행보다 5-7일 늦추는 것은 건엽에서 환원당과 니코틴의 비를 더 좋게 하는 방법일 것이다.

• Journal of Ginseng Research
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• 제33권1호
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• pp.40-47
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• 2009

This study evaluates changes in the chemical composition and bioactivities of American ginseng (Panax quinquefolius L.) processed by boiling in water, $75^{\circ}C$ for 10, 20, 30, and 40 min, and autoclaving at high temperatures, $115^{\circ}C$ for 30 and 60 min and $130^{\circ}C$ for 90 and 120 min. Total ginsenoside contents of boiled ginseng remained relatively unchanged, whereas the contents of autoclaved ginseng samples significantly decreased with an increase of both time and temperature. Compared to unheated ginseng (control), the color of both boiled and autoclaved ginseng decreased in lightness and increased in redness. The acidic polysaccharide contents, the total phenolic contents and the antioxidant capacity of boiled and autoclaved ginseng were higher than the untreated ginseng, with the highest values being exhibited by the autoclaved samples. In particular, the antioxidant capacity of unheated ginseng increased about 2.5 times ($285.7{\pm}14.03\;mg$/100g to $777.2{\pm}26.4\;mg$/100g) when ginseng was autoclaved at $130^{\circ}C$ for 120 min as compared to the control. It was concluded that as American ginseng was processed at a high temperature, especially steam-heated in an autoclave, its chemical constituents changed and, in particular, acidic polysaccharides, total phenolics and antioxidant capacity were considerably increased.

• 한국수산과학회지
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• 제39권1호
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• pp.16-22
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• 2006

Mineral and heavy metal contents were determined in three brown edible seaweeds (sea mustard, Undaria pinnatifida; seaweed fusiforme, Hizikia fusiforme; sea tangle, Laminaria japonica) collected from Gijang and Wando in Korea, and two green seaweeds (sea lettuce, Enteromorpha prolifera; green laver, Monostroma nitidum) collected from Gijang. Seaweeds contained high proportions of ash (13.8-24.8%) and sulfate (1.08-3.25%). In brown seaweeds, ash contents (24.5-24.8%) were higher than in green seaweeds (13.8-15.2%). The differences of mineral contents were remarkable in both Gijang and Wando and in 5 various kinds of seaweeds. Brown seaweeds contained higher amounts of both macro-minerals (657-13,947 mg/100 g; Ca, Mg, Na, K) and trace elements (0.27-12.98 mg/100 g; Fe, Al, Zn, Mn, Cr, Cu, Ni), and green seaweeds also had relatively higher amounts of both macro-minerals (233-5,279 mg/100 g) and trace elements (0.26-10.61 mg/100 g).

• 한국식품조리과학회지
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• 제24권2호
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• pp.198-205
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• 2008

The influence of the yuza juice addition on quality of the doenjang was investigated by analyzing their chemical properties. The 80 days pre-fermented(PFD) and non-fermented(NFD) doenjangs used in the present study were mixed with yuza juice designed at different ratio (0, 1, 3, 5% (w/w)), These doenjangs were fermented for 60 days and then analyzed chemical properties, respectively. The moisture content was higher in yuza juice added groups than control group. But Ash, crude lipid and crude protein contents were higher in control than yuza juice added groups. The pH and formol-N were higher in yuza juice added NFD groups however, acidity was reversed. Among the free sugars, glucose contents was the highest. And, free sugars contents were higher in yuza juice added PFD groups than control group. Five kinds organic acids were detected, and succinic acid content was the highest. The organic acid contents were higher in proportion to adding volume of yuza juice, in all groups. The contents of Free amino acids were higher in yuza juice added PFD groups and among these, 1% yuza juice added PFD group(3970.0 mg%) was the highest. Hunter L value was lower by yuza juice added volume and higher in PFD groups. Hunter a and b values were non-significantly difference in PFD and NFD, respectively.

• Bulletin of the Korean Chemical Society
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• 제19권9호
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• pp.962-967
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• 1998

Block copolymers consisting of poly(rbenzyl L-glutamate) (PBLG) as the hydrophobic part and poly(ethylene oxide) (PEO) as the hydrophilic part were synthesized and characterized. Polymeric micelles of the block copolymers (abbreviated GEG) were prepared by a dialysis method. The GEG block copolymers were associated in water to form polymeric micelles, and the critical micelle concentration (CMC) values of the block copolymers decreased with increasing PBLG chain length in the block copolymers. Transmission electron microscopy (TEM) observations revealed polymeric micelles of spherical shapes. From dynamic light scattering (DLS) study, sizes of polymeric micelles of GEG-1, GEG-2, and GEG-3 copolymer were 106.5±59.2 nm, 79.4±46.0 nm, and 37.9±13.3 nm, respectively. The drug loading contents of GEG-1, GEG-2 and GEG-3 polymeric micelles were 12.6, 11.9, and 11.0 wt %, respectively. These results indicated that the drugloading contents were dependent on PBLG chain length in the copolymer; the longer the PBLG chain length, the more the drug-loading contents. Release of norfloxacin (NFX) from the nanoparticles was slower in higher loading contents of NFX than in lower loading contents due to the hydrophobic interaction between PBLG core and NFX.

• 한국작물학회지
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• 제63권1호
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• pp.18-24
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• 2018

본 연구는 유색 과피 품종의 발아 기간에 따른 화학성분 함량 변화를 조사하여 기능성 식품으로 활용할 기초자료를 제공하기 위하여 흰색 과피 2품종과 흑자색 과피 6품종에 대하여 성분 변화를 분석한 결과는 다음과 같다. 발아 기간이 경과함에 따라 조단백질 함량은 증가하는 경향으로 발아 6일째에 가장 높았다. 조지방 함량은 흰색 과피 품종에서는 발아 후 6일에 가장 높았으나, 흑자색 과피 품종에서는 발아 4일째 감소 후 계속 증가하여 8일에 가장 높았다. 조섬유 함량은 발아 후 8일째까지 가장 높았으나 발아 기간 중 경향이 일정하지 않았다. 유색 과피 품종의 sucrose, glucose 및 fructose 함량은 발아 기간이 경과할수록 증가하였으나, 흰색 과피 품종에서는 glucose 함량이 발아 후 8일에 현미 상태보다 증가하였고 sucrose와 fructose는 일정한 경향이 없었다. 흑자색 과피 품종의 발아현미 GABA, alanine, glutamic acid, asparagine, aspartic acid은 발아 기간이 경과할수록 증가하는 경향이다. 특히 GABA는 172배 증가하였다. 흰색 과피 품종에서는 aspartic acid와 asparagine은 발아 전 현미 함량보다 감소하였다. Lysine은 모든 품종에서 발아 전에는 검출되지 않았으나 발아 2일부터 검출되었는데, 발아 6일에 흰색 과피 품종에서는 6.24 mg/100 g, 유색 과피 품종에서는 15.58 mg/100 g로 증가하였다.

• Carbon letters
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• 제12권3호
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• pp.138-142
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• 2011

Poly(vinyl alcohol) (PVA) composites with various graphite oxide (GO) contents (0 to 10 wt%) were prepared by sonicating the mixture of PVA and GO, followed by crosslinking with glutaraldehyde. GO was pre-treated with oxyfluorination ($O_2:F_2$ = 8:2) in order to modify the surface of GO to allow it to carry hydrophilic functional groups. PVA/GO composite hydrogels were characterized by scanning electron microscopy and Fourier-transform infrared spectrometer (FT-IR). The morphology of the PVA/GO composite hydrogels and the variations in soluble gel portion were investigated under various GO contents and UV irradiation doses. The variation in the chemical structure of photo degraded PVA/GO composite hydrogels was studied by FT-IR. The photochemical stability of PVA/GO composite hydrogels under UV irradiation was found to improve noticeably with increasing content of uniformly dispersed GO.