• Bulletin of the Korean Chemical Society
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• 제7권6호
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• pp.421-425
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• 1986

New di- and triorganotin(IV) complexes of meta- and para-phenylenebisdithiocarbamate(m- and p-pbdtc) have been synthesized and characterized by means of chemical analysis, mass spectrometry, and IR spectroscopy. The reaction of the m-pbdtc ligand with diorganotin(IV) halides resulted in 1:1 products, $R_2Sn{\cdot}m$-pbdtc (R = Me, Cy, n-Bu) of dimeric nature whereas the p-pbdtc ligand led to an oligomeric or polymeric structure. The pbdtc ligands were also reacted with triorganotin(IV) halides to form monomeric complexes, $(R_3Sn)_2{\cdot}pbdtc.$ The tin coordination chemistry of these complexes were also discussed in terms of Sn-C and Sn-S bonding modes.

• 한국토양환경학회지
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• 제4권3호
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• pp.35-43
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• 1999

강둑여과의 적지로 판단되는 지역의 배후 농경지 표층토에 대한 무기질소 변환 활동도를 호흡량 측정기에서 소비한 산소량에 기준하여 조사하였다. 초기 표층토 pH(약 4.8~5.7)를 변화시키지 않고 수분함량을 약 20%로 조정한 상태에서 무기질소의 변환을 관찰한 결과 대조군과 실험군의 뚜렷한 호흡량 및 무기질소변환은 관찰할 수 없었고 조사한 실험조건에서 수분 25%, pH 8 정도에서 가장 활발한 미생물 활동도가 관찰되었다. 또한 초기 ${NH_4}_2$$SO_4$400 mg $NH_4$-N의 농도에서 98%정도의 질산화가 조사되었으나 탈질화는 거의 발생하지 않았다.

• 디지털융복합연구
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• 제11권10호
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• pp.493-505
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• 2013

홍삼추출물이 혈액생화학성분, 대퇴골의 골밀도 및 골무기질 등에 미치는 영향을 알아보기 위하여 난소절제(OVX) 흰쥐에 홍삼추출물을 투여하였으며, 실험결과는 일원변량분산분석과 Scheffe의 사후검정을 통하여 분석하였다. 그 결과 홍삼추출물은 OVX군에 비하여 혈중 알부민, HDL Ca, P, Mg 및 estradiol, 골밀도, 대퇴골의 회분, Ca 및 P을 유의하게 증가시키고, 혈중 ALP, AST, ALT, 혈당, 총콜레스테롤, 중성지질, LDL, creatinine, osteocalcin 및 N-terminal telopeptide를 유의하게 감소시켰다(p < 0.01). 이상의 결과로부터 홍삼추출물은 난소절제로 저하된 간과 신장의 기능, 혈중 당, 지질 및 무기질, 골밀도, 골무기질 함량 및 골다공증관련 대사지표들을 정상수준으로 회복시켜 준다는 것을 알 수 있었다.

• 한국재료학회지
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• 제33권7호
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• pp.295-301
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• 2023

Thermoelectric (TE) energy harvesting, which converts available thermal resources into electrical energy, is attracting significant attention, as it facilitates wireless and self-powered electronics. Recently, as demand for portable/wearable electronic devices and sensors increases, organic-inorganic TE films with polymeric matrix are being studied to realize flexible thermoelectric energy harvesters (f-TEHs). Here, we developed flexible organic-inorganic TE films with p-type Bi_0.5Sb_1.5Te₃ powder and polymeric matrices such as poly(3,4-eethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and poly (vinylidene fluoride) (PVDF). The fabricated TE films with a PEDOT:PSS matrix and 1 wt% of multi-walled carbon nanotube (MWCNT) exhibited a power factor value of 3.96 µW·m^-1·K^-2 which is about 2.8 times higher than that of PVDF-based TE film. We also fabricated f-TEHs using both types of TE films and investigated the TE output performance. The f-TEH made of PEDOT:PSS-based TE films harvested the maximum load voltage of 3.4 mV, with a load current of 17.4 µA, and output power of 15.7 nW at a temperature difference of 25 K, whereas the f-TEH with PVDF-based TE films generated values of 0.6 mV, 3.3 µA, and 0.54 nW. This study will broaden the fields of the research on methods to improve TE efficiency and the development of flexible organic-inorganic TE films and f-TEH.

• 한국환경과학회지
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• 제18권7호
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• pp.811-817
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• 2009

To determine changes in nitrogen contents and optimal rates as N fertilizer, we investigated nitrogen characteristics in the slurry in the respond to the application of 0, 0.5, and 1 g of ferrous sulfate or alum /25g of dairy slurry. Additions of ferrous sulfate or alum increase total nitrogen, inorganic nitrogen, available nitrogen, and predicted available nitrogen contents in dairy slurry, resulting in reduction in pH. The best results were found in the treatment with 0.5 g of ferrous sulfate or alum /25 g of dairy slurry. In conclusion, the use of ferrous sulfate or alum as on-farm amendment to dairy slurry should be represented an alternative to improve N in dairy slurry.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.386-389
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• 2001

본 연구는 P. japonira의 액체배양을 통해 HPLC를 이용하여 유용물질인 cordycepin의 농도를 분석하였다. 배지성분중 무기질소원, 아미노산, 무기염류 및 금속이온의 영향을 검토하였다. 그 결과 균사체의 경우에서는 cordycepin의 농도가 매우 낮음을 알 수 있었고, 배양여액의 경우에서는 $(NH_4)_2HPO_4$. histidine. $CaCO_3$ 등을 첨가했을 때 control에 비해 높은 농도의 cordycepin의 생성을 확인할 수 있었다.

• International Journal of Concrete Structures and Materials
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• 제7권2호
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• pp.119-125
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• 2013

Carbonation is a natural ageing process for cement. This study focuses on how the carbonation rate varies with selected hydration times and atmospheric conditions during the early stages of reacting dried cement paste. Diffuse reflection Fourier transform infrared spectroscopy is shown to be a suitable technique to monitor the formation of carbonates in cement. Combined with a previously developed freeze drying technique, carbonation can be studied at specific hydration stages. In ambient air both calcium hydroxide and calcium silicate hydrate (C-S-H) in cement are carbonated. Increased hydration time enhances the carbon dioxide uptake, which indicates that the calcium in the hydration products reacts more easily than the calcium in the clinker phase. In a humid $CO_2$ atmosphere, the carbonation process is so pronounced that it decomposes C-S-H into calcium carbonate and silica. In a moist $N_2$ atmosphere no carbonation occurs, but the sulfate chemistry of the cement seems to be affected due to the formation of ettringite.

• 한국세라믹학회지
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• 제43권4호
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• pp.207-212
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• 2006

[ ${\varepsilon}-caprolactam$ ] was polymerized in the layers of the [DEACOOH]-Montmorillonite intercalations complex at high temperatures ranging from 250% to 260% formed from Na-Montmorillonite and 10-Carboxy-n-decyldimethylethylammonium bromide to achieve [DEACOOH]-Polycaprolactam-Montmorillonite, in which an inorganic polymer (montmorillonite) is chemically combined with an organic polymer (polycaprolactam). The results of X-ray and IR analyses for the samples obtained after polymerization showed that the polymerization reaction was successfully accomplished. For the purpose of studying the polymeric reaction product more precisely, the polymerized product was separated from the silicate layers and analyzed with an X-ray diffractometer and an IR-spectrometer. A comparison of the results of the X-ray and IR analyses of the separated polymer and the polymer that was synthesized by the reaction of ${\varepsilon}-caprolactam$ solely with the organic cation without montmorillonite showed that the obtained both polymers are identical compounds.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.56-59
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• 2009

In the nineties the invention of the InGaN blue LED has innovated illumination technology. Currently LCD backlighting and more and more general lighting applications are based on white LEDs comprising of inorganic phosphors and blue emitting InGaN chip. Well established phosphor materials are ortho silicates and garnets like yellow emitting YAG:Ce. In our paper we demonstrate that garnet materials also allow for green light emission for both, general lighting and backlighting LED applications.

• 한국초지조사료학회지
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• 제17권3호
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• pp.293-304
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• 1997

A field experiment was conducted at the forage experimental plots, Seoul National University, Suweon h m 1995 to 1996 to determine the effect of legume residues as a N source and N fertilizer on corn (Zea mays L.) silage yield, N uptake, and availability of inorganic N in the soil. Corn was grown following (i) red clover (Trifolium pratense L.), (ii) crimson clover (Trifolium incarnatum L.), (iii) alfalfa (Medicago sativa L.) and (iv) winter fallow. The plots were split into two rates of fertilizer N (0 and 90kg Nlha) in a split-plot experimental plan. Compared with fallow treatment, legumes depleted soil water in the surface 15cm at corn planting by 17 to 26%. As a result, corn emergence was markedly delayed with legume residues by 8 to 11 days. Corn silage DM yield was significantly reduced in the presence of legume residues by 2.0 to 3.4 and 1.5 to 2.5 tonlha compared with winter fallow treatment at 0 and 90kg fertilizer Nlha, respectively, but no significant difference in the corn DM yield was found between legume residue treatments. There was an overall tendency for increased corn yields with 90kg fertilizer Nlha compared to Okg fertilizer Nlha, although not all yield increases were significantly greater. The corn yield response to applied N suggests that a source of N from legume residues was not sufficient for a succeeding corn crop. There was significantly more N (P