• Applied Chemistry for Engineering
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• v.28 no.5
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• pp.571-575
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• 2017

In this study, cadmium telluride (CdTe) quantum dots were synthesized by using ultrasonic irradiation method. Optical properties and structural characteristics of the CdTe quantum dots were analyzed by two main variables; the ratio of the precursor and the synthesis time. As the synthesis time increased, the band gap reduction was observed with the growth of CdTe quantum dots. As for the luminescence properties, the red shift appeared at 510~610 nm wavelength range. Also, it was confirmed that the red shift occurs rapidly as the ratio of Te increases. According to PL peak intensity, the highest intensity was shown at 180 to 240 min. Structural characteristics of CdTe quantum dots were investigated through XRD and TEM, and the cubic zinc blend structure was observed. The size of quantum dots was about 2.5 nm and uniformly dispersed when the synthesis time took 210 min. In addition, the apparent crystallinity was discovered in FFT image.

• Journal of Korean Medicine Rehabilitation
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• v.21 no.2
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• pp.63-85
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• 2011

Objectives : This study was carried out to know the effects of Danggwisayeokgaohsuyusaenggang-tang(hereinafter referred to DST) on arthritis induced by collagen on DBA/1 OlaHsd mice. Methods : For this purpose, DST was orally administered to mouse with arthritis induced by collagen II. Cytotoxicity, high performance liquid chromatograph(HPLC) analysis, arthritis index, value of immunocyte in draining lymph node and paw joint, cytokine were measured in vivo. Results : 1. The cytotoxicity against human fibroblast cells(hFCs) was not measured in any concentration. 2. In HPLC analysis, There are high peak patterns at 8 minute(min), 12 min, 35 min, 45 min. 3. The arthritis index was decreased significantly. 4. The degree of arthritis induced damage of joint of DST group is slight compared with control group in histopathologic observation(Hematoxylin and eosin stain(H&E), Masson's trichrome(M-T) staining). 5. In total cell counts of draining lymph node(DLN) and paw joint, the cells in DLN decreased significantly on DST 200 mg/kg and the cells in paw joint decreased significantly on 200 mg/kg and 50 mg/kg. 6. In DLN, $CD4^+/CD25^+$, $CD3^+/CD69^+$, major histocompatibility complex(MHC), class-II/$CD11c^+$ cells decreased significantly on DST 200 mg/kg and 50 mg/kg $CD3^+/CD8^+$ cells decreased significantly on DST 200 200 mg/kg, $CD4^+$, $CD3^+/CD44^+$ cells decreased. 7. In paw joints, $CD4^+$, $CD11b^+/Gr-1^+$ cells decreased significantly on DST 200 mg/kg and 50 mg/kg. 8. In joints, levels of $IL-1{\beta}$, IL-6, $TNF-{\alpha}$, cyclo-oxygenase-2(COX-2), NOS-II were decreased on DST 200 mg/kg and DST 50 mg/kg. 9. In analysing of cytokine in CD3/CD28 activated spleen, IL-17 was decreased significantly, IL-4 was increased significantly $INF-{\gamma}$ was decreased on DST 200 mg/kg. 10. In analysing of cytokine in collagen activated spleen, IL-17 were decreased significantly, IL-4 was increased significantly. Conclusions : This results demonstrated that DST suppressed the inflammatory progression of collagen-induced arthritis(CIA) mice and supported further studies are required to survey continuously in looking for the effective substance and mechanism in the future.

• Current Photovoltaic Research
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• v.2 no.4
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• pp.152-156
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• 2014

We report hybrid solar cells fabricated with polymer/fullerene bulk heterojunction layers that contain inorganic nanocrystals synthesized by in-situ reaction in the presence of polymer chains. The inorganic (cadmium sulfide) nanocrystal ($CdS_{NC}$) was generated by the reaction of cadmium acetate and sulfur by varying the reaction time up to 30 min. The synthesized $CdS_{NC}$ showed a rectangular flake shape, while the size of $CdS_{NC}$ reached ca. 150 nm when the reaction time was 10 min. The performance of hybrid solar cells with $CdS_{NC}$ synthesized for 10 min was better than that of a control device, whereas poor performances were measured for other hybrid solar cells with $CdS_{NC}$ synthesized for more than 10 min.

• Food Science and Preservation
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• v.12 no.3
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• pp.209-215
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• 2005

Response surface methodology(RSM) was applied to monitor the elimination rate of heavy metals(Pb, Cd) and soluble solids depending on the steaming and roasting conditions of Polygonatum odoratum roots. Experiments of 16 different steaming and roasting conditions based on a central composite design for steaming time($60{\sim}180$ min), roasting temperature($110{\sim}150^{\circ}C$), and roasting time($10{\sim}50$ min) were conducted, thereby predicting the steaming and roasting conditions for the maximal responses; soluble solids($71.47\%$) at 65.24 min, $126.93^{\circ}C$ and 37.58 min; Pb removal rate($18.87\%$) at 71.23 min, $119.81^{\circ}C$ and 24.35 min; Cd removal rate($50,85\%$) at 160.89 min, $126.43^{\circ}C$ and 15.81 min, respectively. The optimum conditions estimated by RSM for the maximized values of soluble solids and heavy metal elimination rates were $165{\sim}180$ min of steaming time, $120{\sim}135^{\circ}C$ of roasting temperature, and $30{\sim}45$ min of roasting time, respectively. These estimated values were in agreement with those measured by real experiments.

• Electrical & Electronic Materials
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• v.1 no.1
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• pp.26-34
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• 1988

Sintered CdS/CdTe solar cells have been farbricated by coating a (Cd+Te) slurry on sintered CdS films followed by the sintering at 625.deg.C for one hour with various heating rates. When cadmium and tellurinm powders are used instead of CdTe powder to form CdS/CdTe junction, CdTe is formed in the temperature range of 290.deg.C-400.deg.C. The microstructure of the CdTe films depends strongly on the heating rate of the sintering due to the low melting temperature and the high vapor pressure of the elemental Cd and Te. An optimum heating rate obtain CdTe films with uniform and dense microstructure which, in turn, improves the efficiency of the sintered CdS/CdTe solar cells. All-polycrystalline CdS/CdTe solar cells with an efficiency of 9.57% under 50mW/cm$^{2}$ tungsten light have been farbricated by using a heating rate of 14.deg.C/min.

• Food Science and Biotechnology
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• v.14 no.6
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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 $40^{\circ}C$.

• JSTS:Journal of Semiconductor Technology and Science
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• v.8 no.4
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• pp.326-332
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• 2008

In this work CdS films were prepared by using chemical bath deposition, which is simple and inexpensive technique suitable for large deposition area. Annealing in air at different temperatures (300, 350, 400, 450 and $500^{\circ}C$) at constant time of 30 min, also for different times (15, 30, 45, 60 and 90 min) at constant temperature ($300^{\circ}C$) is achieved. X-Ray analysis has confirmed the formation of cadmium oxide (CdO) with slight increase in grain size, shift towards lower scattering angle due to relaxation in the tensile strain for deposition films, and structure change from cubic and hexagonal to the hexagonal. From electrical properties, significant increase in electrical conductivity appeared in samples annealed at $300^{\circ}C$ for 60 min, and at $350^{\circ}C$ for 30 min.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.470-470
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• 2011

반도체 집적회로의 고집적화 및 고성능화를 위한 기본 소자(MOSFET)의 미세화 및 단위공정의 물리적 한계를 극복하기 위한 다양한 연구가 진행되고 있다. 그 중 다양한 나노입자를 이용한 나노소자 제작 연구가 활발하게 이루어지고 있다. 하지만 이러한 나노입자를 이용한 나노소자의 제작에 있어서 원하는 위치의 나노입자의 배열과 정렬의 어려움을 겪고 있다. 이를 위해서 본 연구에서는 자기조립특성을 가지는 DNA 분자와 CdSe/ZnS 나노입자들의 표면 기능화를 통해서 상호 결합시키는 실험을 하였다. DNA 분자를 형틀로 이용하여 CdSe/ZnS 나노입자를 선택적 배열하고 전자 소자화하기 위해서는 CdSe/ZnS 나노입자의 표면 기능화가 필수적이다. 이를 위하여 무극성인 CdSe/ZnS 나노입자들과 DNA 분자의 phosphate backbone의 음전하와의 경합 특성을 향상시키기 위하여 이들 나노입자의 표면을 양전하로 치환하는 실험을 수행하였다. Core 나노입자인 CdSe 나노입자를 제작한 다음에 CdSe 보다 높은 band gap을 가지고 lattice mismatch가 적은 ZnS 로 shell 층을 형성하는 2-step 방법을 이용하여 합성한 CdSe/ZnS 나노입자를 무극성 용매인 chloroform 용액 0.5 ml에 분산시키고 DMAET 0.3 ml 와 Methanol 0.1 mg/ml를 이용하여 리간드들을 바꿔주고 과잉된 리간드인 DMAET를 제거하기 위해 Methanol로 3차례 세척한 다음 증류수에 용해시키는 실험을 하였다. 나노입자 기능화 과정 이후 기능화 여부를 판단하기 위하여 FT-IR spectroscopy 와 zeta potential 측정을 통하여 나노입자 표면의 변화와 전위를 측정하였다.

• Journal of Oral Medicine and Pain
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• v.21 no.2
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• pp.351-367
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• 1996

In the field Of individual identification in forensic Science, if the body is charred, it is sometimes impossible to identify the morphologic changes and charred tissue such as blood, muscle and bone can not be identified by forensic microbiologic method such as DNA typing. So the author used the characteristics of teeth which is relatively firm compare to other organs and stable to external environment such as heat and also possess cells needed for the DNA typing. The author conducted the experiment on teeth to detect DNA related to individual identification regarding to temperature in which other charredorgans can not be detected. The experiment was done on 64 extracted third molars consisted of unheated ones, and heated teeth to $100^{\circ}C$, $150^{\circ}C$, $200^{\circ}C$ for 45 min, 90 min, and 120 min respectively and to $250^{\circ}C$ for 45 min. DNA was extracted from each tooth and amplified fragment length polymorphism procedure(AMP-FLPs) using polymerase chain reaction(PCR) was applied and observed for the matching DNA in HumTH01 and HumCD4 locus and the followings Are the results : 1. It was able to detect matching DNA in HumTH01 and HumCD4 locus in every teeth which no heating has been done. 2. It was able to detect matching DNA in HumTH01 and HumCD4 locus in every teeth heated to $100^{\circ}C$ for 45, 90 and 120 min. 3. It was able to detect matching DNA in HumTH01 and HumCD4 locus in teeth heated to $l00^{\circ}C$, $200^{\circ}C$ for 45, 90, 120 min. 4. It was impossible to detect matching DNA in HumTH01 and HumCD4 locus in teeth heated to $250^{\circ}C$. So, it is possible to extract DNA from teeth that otherwise can not be extracted from other organs in the charred body and it can be concluded that teeth are highly reliable and applicatable as forensic odontology for individual identification.

• Proceedings of the Materials Research Society of Korea Conference
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• 2005.05a
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• pp.81-81
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• 2005