• 폴리머
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• 제30권3호
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• pp.266-270
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• 2006

Poly [(dimethylmethylvinyl)siloxane 공중합체(PMViS)를 phosphorus oxychloride $(POCl_3)$와 반응시켜 poly [(dimethylmethylvinyl) siloxane] phosphine oxides (PMViSPO)를 제조하였다. Cadmium selenide (CdSe)는 cadmium oxide(CdO), tetradecylphosphonic acid(TDPA), trioctylphosphine oxide(TOPO)를 $300^{\circ}C$에서 반응시키고 여기에 Se를 용해시킨 tributylphosphine(TBP)과 trioctylphosphine(TOP)을 가한 다음 $320^{\circ}C$에서 반응시켜 제조하였다. 또한 CdSe 제조 용액에 PMViSPO를 가하여 CdSe-SPO adduct를 제조하였다. 백금 촉매 존재 하에서 $\alpha,\omega-vinyl$ poly(dimethylsiloxane) (VPMS), HPMS, CdSe 또는 CdSe-SPO를 고속 교반기에 취하고 컴파운딩하여 CdSe 함유 액상실리콘 고무 composite (LSRC-1)와 CdSe-SPO 함유 LSR composite (LSRC-2)를 제조하였다. 제조한 LSR composites 내에 함유된 형광 물질인 CdSe nanoparticles의 분산형태를 측정하여 입자 크기가 $30\sim50nm$인 입자가 균일하게 분포되어 있음을 확인하였고 LSRC-2의 분산도가 LSRC-1보다 우수함을 확인하였다. 또한 CdSe 입자의 개수를 측정한 결과 동일한 면적에 대하여 166개와 202개로 보다 많은 개수의 CdSe가 LSRC-2에 함유됨을 알 수 있었다. LSR composites의 열적 특성을 측정한 결과 CdSe-SPO가 함유된 LSRC-2의 열안정성이 높게 나타났다.

• 한국수산과학회지
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• 제35권5호
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• pp.480-484
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• 2002

넙치 (Paralichthys olivaceus)를 카드뮴 아치사 농도인 5, 10, 50, 100$\mu$g/L의 구간에 노출시켜 30일 동안 아가미, 간, 신장, 창자에서 축적되는 정도를 조사하였다. 넙치에서 카드뮴의 축적은 아가미, 창자와 간에서 카드뮴의 노출농도와 노출기간에 따라서 증가를 하였으며, 그러한 양상은 선형적으로 증가를 하였다 노출 20일까지는 기관별 축적순서는 아가미>간>창자>신장의 순서로 나타나지만, 노출 30일 이후에는 아가미와 간에서 축적이 완만한 경향을 나타내며, 창자의 축적은 급격한 경향을 나타내어 기관별 축적순서는 창자>아가미>간>신장의 순서로 나타났다. 카드뮴의 넙치에 대한 축적계수는 아가미와 신장, 창자에서 노출농도에 반비례하며, 노출 시간에 따라 증가하는 경향을 나타났다.

• 방사선산업학회지
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• 제8권1호
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• pp.17-22
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• 2014

In this study, we prepared CdTe/CdS solar cells using a thermal vacuum evaporation method. In particular, $CdCl_2$ treatment was attempted using this same method at $400^{\circ}C$ for 30 min. The prepared CdTe/CdS solar cells were investigated using Fouier transform infrared spectrometry (FTIR), field emission scanning electron microscopy (FE-SEM), and a solar simulator system including light absorption properties, morphological properties, and power conversion efficiency (PCE). In addition, we investigated the gamma-irradiation treatment at dose rates of 0 Gy, 500 Gy, 1 kGy, 10 kGy, and 30 kGy. The characteristics of gamma-irradiation treatment were studied based on the same method described above. In particular, it showed increased values as 0.826% higher than the non-irradiation of 0.448% from PCE analysis.

• 한국식품저장유통학회지
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• 제30권5호
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• pp.797-810
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• 2023

Elaeagnus umbellata leaves have been reported to suppress inflammation, allergic responses, lung cancer proliferation and oral bacterial growth. Cadmium (Cd) is a heavy metal that has been found to cause many toxicities, including liver toxicity. The aim of this study was to evaluate the capacity of 70% ethanol extract of E. umbellata leaves (EUL) to protect human hepatocytes from Cd toxicity. After exposure of HepG2 cells to Cd at 10 𝜇M for 24 h, cell viability, expression levels of apoptosis- and antioxidant-related proteins, reactive oxygen species (ROS) accumulation and Cd uptake were assessed. EUL protected HepG2 cells from Cd-induced apoptosis as determined by MTT assay. A decrease in caspase-3 and p-p53 protein levels was observed in cells pretreated with EUL prior to Cd exposure. Furthermore, the Cd-induced increase in intracellular DCF fluorescence was attenuated by EUL, indicating that the Cd-induced apoptosis preventing effect was associated with the suppression of ROS accumulation. Moreover, EUL's effects on the inhibition of p38, JNK, and AKT phosphorylation also appear to be associated with protection against Cd toxicity. Moreover, EUL upregulated Cd-depressed expression of Nrf2, HO-1, catalase, and MT-1,2 proteins, suggesting that Cd uptake-induced apoptosis in HepG2 cells may be inhibited by EUL's antioxidative potential.

• Environmental Engineering Research
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• 제21권1호
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• pp.15-21
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• 2016

Magnesium potassium phosphate cement (MKPC) is an effective agent for solidification/stabilization (S/S) technology. To further explore the mechanism of the S/S by MKPC, two kinds of Cd including $Cd(NO_3)_2$ solution (L-Cd) and municipal solid waste incineration fly ash (MSWI FA) adsorbed Cd (S-Cd), were used to compare the effects of the form of heavy metal on S/S. The results showed that all the MKPC pastes had a high unconfined compressive strength (UCS) above 11 MPa. For L-Cd pastes, Cd leaching concentration increased with the increase of Cd content, and decreased with the increase of curing time. With the percentage of MSWI FA below 20%, S-Cd pastes exhibited similar Cd leaching concentrations as those of L-Cd pastes, while when the content of MSWI FA come up to 30%, the Cd leaching concentration increased significantly. To meet the standard GB5085.3-2007, the highest addition of S-Cd was 30% MSWI FA (6% Cd contained), with the Cd leaching concentration of 0.817 mg/L. The S/S of L-Cd is mainly due to chemical fixation, and the hydration compound of Cd was $NaCdPO_4$, while the S/S of S-Cd is due to physical encapsulation, which is dependent on the pore/crack size and porosity of the MKPC pastes.

• Food Science and Biotechnology
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• 제14권6호
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• pp.793-797
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• 2005

Optimum conditions for cholesterol removal in egg yolk were evaluated based on ratio of egg yolk-to-water, crosslinked ${\beta}$-cyclodextrin (${\beta}$-CD) concentration, and mixing temperature, time, and speed by adding crosslinked ${\beta}$-CD treated with adipic acid. Cholesterol removal in egg yolk-water mixture increased with increasing ${\beta}$-CD level (10-25%). About 95% was removed by 25% ${\beta}$-CD at 1:1 ratio of egg yolk-to-water and 800 rpm mixing at $40^{\circ}C$ for 30 min. In recycling study, removal rates were measured using ten times recycled crosslinked ${\beta}$-CD in egg yolk, and 85% cholesterol removal was observed with eight times reuse. These results indicated that over 90% cholesterol was removed at 1:1 ratio of egg yolk-to-water, 20% crosslinked ${\beta}$-CD addition, and 30 min mixing with 600 rpm at $40^{\circ}C$.

• The Korean Journal of Ecology
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• 제20권1호
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• pp.35-41
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• 1997

Effects of cadmium on growth and nitrogen fixation activity of Melilotus suaveolens, a biennial legume plant dominating in the area of poor soil were quantitatively analyzed during the growing period. Cadmium treatments of 10, 30 and 100 ppm resulted in 12, 22 and 35% inhibition of plant height and 14, 25 nd 26% reduction of chlorophyll contents of leaves, respectively. The plant biomass reduced 51, 70 and 89% for leaves, 33, 50 and 59% for stems, and 42, 52 and 70% for roots, respectively by 10, 30 and 100 ppm Cd treatments. Cadmium contents of roots treated with 10, 30 and 100 ppm Cd were 62, 112 and 183 folds higher than that of the control, respectively. Cadmium contents of stems were about 1/2.2 of those of roots, but leaves contained only 1/27.8 of those of roots. Cadmium treatments resulted in increase of T/R ratios and decrease of F/C ratios significantly in the later growth period. Nodule formation was reduced to 8% in 42 days by the treatment of 100 ppm Cd. Specific nitrogen fixation activity of nodules attained 61.0, 24.0, 1.6 and 0.7 mol $C_2H_4{\cdot}g$ fr wt $nodule^{-1}{\cdot}h^{-1}$ on 42nd day, respectively for 0, 10. 30 and 100 ppm of Cd treatments. Total amount of nitrogen fixation per plant reduced by 73, 98 and 99% with the treatments of 10, 30 and 100 ppm Cd.

• 한국광학회지
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• 제3권1호
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• pp.55-62
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• 1992

본 연구에서는 CdS, CdSe, ZnS, ZnSe 반도체를 첨가한 SK-16 유리와 ZK-1 유리를 직접 제작하고 열처리하여 유리속에 반도체의 미세결정을 생성시켜 착색유리를 만들고 sharp-cut용 광학 filter로써의 특성을 조사하였다. CdS, CdSe, ZnS 및 ZnSe 반도체를 첨가한 SK-16유리는 열처리돈도를 달리하였을 경우 광흡수단을 변화시킬 수 있는 범위가 30nm정도로 아주 좁았다. 그러나 $CdS_{1-x}Se_x$를 첨가한 SK-16 유리는 x값을 변화시키면서 열처리 함으로써 광흡수단을 ~130nm범위에서 변화시킬 수 있었고 광흡수계수도 높아 sharp-cut용 광학 filter용으로 좋은 특성을 나타내었다. CdSe와 $CdS_{0.5}Se_{0.5}$ 반도체를 첨가한 ZK-1 유리는 열처리온도를 달리 함으로서 흡수단을 변화시킬 수 있는 범위가 ~100nm나 되고 광흡수게수도 아주 높아 sharp-cut용 광학 fiter로 아주 우수한 특성을 나타내었다.

• 한국재료학회지
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• 제30권1호
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• pp.1-7
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• 2020

Doping or incorporation with exotic elements are two manners to regulate the optoelectronic properties of transparent conducting (TCO) cadmium oxide (CdO). Nevertheless, the method of doping host CdO by CdTe semiconductor is of high importance. The structural, optical, and electrical properties of CdTe-doped CdO films are studied for the sake of promoting their conducting parameters (CPs), including their conductivity, carrier concentration, and carrier mobility, along with transparency in the NIR spectral region; these are then compared with the influence of doping the host CdO by pure Te ions. X-ray fluorescence (XRF), X-ray diffraction (XRD), optical absorption spectroscopy, and electrical measurements are used to characterise the deposited films prepared by thermal evaporation. Numerous results are presented and discussed in this work; among these results, the optical properties are studied through a merging of concurrent BGN (redshift) and BGW (blue shift) effects as a consequence of doping processes. The impact of hydrogenation on the characterisations of the prepared films is investigated; it has no qualitative effect on the crystalline structure. However, it is found that TCO-CPs are improved by the process of CdTe doping followed by hydrogenation. The utmost TCO-CP improvements are found with host CdO film including ~ 1 %Te, in which the resistivity decreases by ~ 750 %, carrier concentration increases by 355 %, and mobility increases by ~ 90 % due to the increase of N_carr. The improvement of TCO-CPs by hydrogenation is attributed to the creation of O-vacancies because of H₂ molecule dissociation in the presence of Te ions. These results reflect the potential of using semiconductor CdTe -doped CdO thin films in TCO applications. Nevertheless, improvements of the host CdO CPs with CdTe dopant are of a lesser degree compared with the case of doping the host CdO with pure Te ions.

• 한국환경농학회지
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• 제4권1호
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• pp.11-17
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• 1985

Zn와 Cd을 무저(無底)폿트(${\phi}30cm{\times}70cm$)에 Cd는 5, 10, 30ppm, Zn은 150, 300, 600ppm으로 처리(處理)하고 옥수수(수원(水原) 19호(號))를 파종(播種)하여 발아후(發芽後) 15일(日), 30일(日), 45일(日)의 식물체(植物體) 생육(生育), 엽중(葉中) peroxidase활성(活性), 엽녹소(葉綠素) 합량(合量), 무기성분(無機成分) 함량(含量) 및 중김속(重金屬) 함량(含量)을 조사(調査)한 결과(結果)는 다음과 같다. 1) 토양중(土壤中) Cd, Zn의 첨가농도(添加濃度)가 높아질수록 간장(稈長) 및 건물중(乾物重)이 유의성(有意性)있게 감소하였다. 2) 식물체중(植物體中) Cd함량(含量)이 높아질수록 엽중(葉中) peroxidase 활성(活性)은 증가(增加)하나, Zn은 함량(含量)이 높아질수록 감소(減少)하는 경향(減少)이었다. 3) 식물체중(植物體中) Cd, Zn 농도(濃度)가 증가(增加)할수록 chlorophyll함량(含量)은 감소(減少)되었다. 4) 토양중 Cd 첨가농도(添加濃度)가 높아질수록 식물체중(植物體中) N함량(含量)은 증가(增加)되나 P, K, Ca, Mg, $SiO_2$함량(含量)은 감소(減少)되었다. 반면(反面) 토양중(土壤中) Zn첨가농도(添加濃度)가 높아질수록 P 및 SiO함양(含量)은 증가(增加)되나 N, Ca, Mg함양(含量)은 감소(減少)되는 경향(傾向)이었다. 5) 식물체중(植物體中) Cd, Zn흡수량(吸收量)은 시기(時期)가 경과할수록 증가(增加)하나 이들 함양(含量)은 일정(一定)한 경향(傾向)이 없었다. 6) 시일(時日)이 경과함에 따라 식물체중(植物體中) Cd흡수(吸收)는 Zn의 첨가농도(添加濃度)가 높아질수록 감소(減少)된 반면(反面) 식물체중(植物體中) Zn흡수(吸收) Cd의 낮은 첨가농도(添加濃度)에서 감소(減少)되었다.