• Journal of Nutrition and Health
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• v.44 no.6
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• pp.474-480
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• 2011

Calcium (Ca) is an essential element to maintain body homeostasis. However, many factors disturb calcium absorption. Aspartic acid chelated calcium (AAC) was synthesized by new methods using calcium carbonate and aspartic acid. This study was carried out to investigate the bioavailability of AAC in Ca-deficient rats. The experimental groups were as follows: NC; normal diet control group, CD-C; untreated control group of Ca-deficient (CD) rats, CD-$CaCO_3$; $CaCO_3$ treated group of CD rats, CD-AAC; AAC treated group of CD rats, and CD-SWC; and seaweed-derived Ca treated group of CD rats. The Ca content of various types of Ca was held constant at 32 mg/day, and the four CD groups were fed for 7 days after randomized grouping. Ca content in serum, urine, and feces within feeding periods were analyzed to confirm Ca absorption. Serum Ca content was significantly higher in the CD-AAC (11.24 mg/dL) and CD-SWC (10.12 mg/dL) groups than that in the CD-C (8.6 mg/dL) group 2 hours following the first administration. The Ca content in feces was significantly lower in the CD-AAC (35.4 mg/3 days) and CD-SWC (71.1 mg/3 day) groups than that in the CD-$CaCO_3$ (98.7 mg/3 days) group (p > 0.05). AAC had a 2.3-fold higher absorption rate of Ca than that of SWC. No differences in fibula length were observed in the NC and CD groups. The fibula weights of the CD-AAC (0.33 g) and CD-SWC (0.33 g) groups increased compared to those in the CD-C (0.27 g) group; however, no significant difference was observed between the CD groups. We conclude that bioavailability of AAC is higher than that of seaweed-derived Ca or inorganic Ca. Thus, these findings suggest the AAC has potential as a functional food material related to Ca metabolism.

• Nutritional Sciences
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• v.6 no.4
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• pp.223-228
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• 2003

This study was carried out to investigate the effects of vitamin E on the cadmium contents of bone and on the calcium and phosphorous contents of the blood, urine and feces. Male Sprague-Dawley rats weighing 100$\pm$10g were randomly assigned to one normal group and three cadmium poisoned groups. The cadmium poisoned groups consisted of a vitamin E free diet (Cd-0E) group; a 40 mg vitamin E /kg diet (Cd-40E) group; and a 400 mg/kg diet (Cd-400E) group. Experimental animals were maintained on their respective diets for 20 weeks and were simultaneously administered 50 ppm $Cd^{2+}$ dissolved in the drinking water. At the end of the trial, the average hematocrit value in the Cd-0E group was 28.13% lower than in the normal group. However, the average hematocrit value in the Cd-400E group was significantly higher than in the Cd-0E and Cd-40E groups. WBC levels in the cadmium-poisoned groups were lower than in the normal group, but Cd-400E group levels were significantly higher than in the Cd-0E and Cd-40E groups. The contents of calcium of tibia has no significant difference between normal group and cadmium exposed group at $10^{th}$ week After 20 weeks, the calcium contents of the tibia in the Cd-0E and Cd-40E groups were lower than in the normal group by 25.5% and 22.1 %, respectively, although the calcium contents of the tibia in the Cd-400E group were higher than in the normal group. After 10 weeks, the calcium contents of the femur in the Cd-0E and Cd-40E groups were 19.25% and 15.45% lower than in the normal group, respectively, but the calcium contents of the femur in the Cd-400E group were at the same levels as in the normal group. The levels of calcium in the femur after 20 weeks were similar to the 10-week levels. Calcium levels of the urine in the Cd-0E and Cd-40E groups were 3.92 fold and 2.92 fold higher, respectively, than in the normal group, but levels in the Cd-400E group were significantly lower than in either the Cd-0E group or the Cd-40E group. Calcium levels of the feces in cadmium-poisoned groups were significantly higher than in the normal group, although levels in the Cd-400E group were significantly lower than in the Cd-0E and Cd-40E groups. Phosphorous levels of the blood in the Cd-0E group were 17% lower than in the normal group, although levels in the Cd-400E group were significantly higher than in the Cd-0E group. Phosphorous levels of the urine in the Cd-0E and Cd-40E groups were significantly higher than in the normal group, while Cd-400E group levels were found to be at the same level as in the normal group. Cadmium contents of the tibia in the Cd-40E and Cd-400E groups were 13% and 17% lower, respectively, than in the Cd-0E group. Regarding cadmium levels in the femur, only the Cd-400E group achieved lower levels (10% lower) than the Cd-0E group. In conclusion, vitamin E supplementation resulted in a suppression of the release of calcium from bone, and a reduction in the excretion of calcium via the urine and feces, thus having a normalizing effect on calcium metabolism in rats with chronic cadmium poisoning.

• Journal of Ginseng Research
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• v.47 no.1
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• pp.155-158
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• 2023

In the present study, we investigated whether treatment with KRG improve the parameters of immune activity such as the cytotoxicity, populations of CD4⁺ CD8⁺T cell, CD3^-CD172^-CD8⁺ NK cell and CD172⁺ monocyte as well as natural cytotoxicity receptors such as Nkp46, Nkp44, Nkp30. In results, KRG significantly increased these immune activities. These results indicate that KRG has distinct immuneenhancing effects by increasing the roles of T cells and NK cell in porcine.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.4
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• pp.614-620
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• 2004

This study was to determine the effect of dietary $\beta$-cyclodextrin ($\beta$CD) on egg quality and cholesterol content of egg yolk. One-hundred 28-week-old laying hens were randomly distributed into five groups of twenty hens each and maintained in individual laying cages for 10 weeks of the experiment. They were assigned to the five treatments of experimental layer diets containing 0, 3, 5, 7 or 10% pure $\beta$CD of diets. Food intake, egg production and egg weight varied slightly and insignificantly in the hens fed with 0, 3, 5 or 7% $\beta$CD-added diets. But food intake, egg production, and egg weight were uniformly lower (p＜0.05) in the hens fed with 10% $\beta$CD-added diets. Food conversion rate, when expressed per number egg, was impaired (p＜0.05) without having an obvious relation to the dietary $\beta$CD level. No difference in haugh unit, egg yolk color, and egg shell thickness was found among treatment. The cholesterol content of egg yolks was significantly decreased (p＜0.05) to 3.76, 5.12, 5.49 and 6.48 mg/g yolk in $\beta$CD 3, 5, 7 and 10% treatments respectively when compared to that of the $\beta$CD 0% group. The cholesterol content of eggs, when expressed in mg/60 g egg, was greatly (p＜0.05) decreased to 54, 71, 77 and 86 mg in $\beta$CD 3, 5, 7 and 10% treatments when compared to that of the $\beta$CD 0% group. The most striking effects (p＜0.05) were observed in $\beta$CD 5% and 7% treatments, whose cholesterol content decreased from 28.19% to 30.23%. In conclusion, $\beta$CD added-diets fed to laying hens can reduced the cholesterol content of egg yolk, and this new type of egg yolk with lower cholesterol can be considered a functional livestock food.

• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.248-250
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• 1987

Transparent CdS films with low electrical restivity on glass substrates were prepared by coating a CdS slurry which contained 10 wt.% $CdCl_2$, and sintering in a nitrogen atmosphere at $600^{\circ}C$ for 2hr. All-polycrystalline CdS/CdTe solar cells were fabricated by coating CdTe slurries, which contained 1.0 or 4.5 wt.% $CdCl_2$, on the sintered CdS films and sintering at $700^{\circ}C$ for various periods of sintering. The spectral responses of the sintered CdS/CdTe solar cells were measured and compared with theoretically calculated quantum efficiency. The spectral responses of the sintered CdS/CdTe solar cells in the short-wavelength region decreases with-increasing sintering time. The poor response in this region is attributed to the existence of the Cd-S-Te solid solution in the compositional junction. The decrease in the maximum response in the long-wavelength region as the sintering exceeds certain time appears to be caused by the increase in the depth of the buried homo junction and by the increase in the series resistance. The $CdCl_2$ in the CdTe layer during sintering enchances the interdiffusion of S, Te or donor impurities across the metallurgical Junction causing the formation of deeper n-p junction in the CdTe layer.

• Bulletin of the Korean Chemical Society
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• v.18 no.5
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• pp.473-474
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• 1997

• Korean Journal of Materials Research
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• v.8 no.6
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• pp.493-498
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• 1998

CdTe films were deposited by close spaced sublimation with various substrate temperatures, cell areas, and thicknesses of CdTe and ITO layers and their effects on the CdS/CdTe solar cells were investigated. The resistivity of CdTe layers employed in this study was 3$\times$ $10^{4}$$\Omega$cm For constant substrate temperature the optimum substrate ternperature for CdTe deposition was $600^{\circ}C$. To obtain larger grain size and more compact microstructure, CdTe film was initially deposited at 62$0^{\circ}C$, and then deposited at 54$0^{\circ}C$. The CdTe film was annealed at 62$0^{\circ}C$ and $600^{\circ}C$ sequentially to maintain the CdTe film quality. The photovoitaic cell efficiency improved by the "two-wave" process. For constant substrate temperature, the optimum thickness for CdTe was 5-6$\mu m$. Above 6$\mu m$ CdTe thickness, the bulk resistance of CdTe film degraded the cell performance. As the cell area increased the $V_{oc}$ remained almost constant, while $J_{sc}$ and FF strongly decreased because of the increase of lateral resistance of the ITO layer. The optimum thickness of the ITa layer in this study was 300~450nm. In this experiment we obtained the efficiency of 9.4% in the O.5cm' cells. The series resistance of the cell should be further reduced to increase the fill factor and improve the efficiency.

• Journal of the Korean institute of surface engineering
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• v.42 no.2
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• pp.63-67
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• 2009

CdSe is one of the composite semiconductor materials used in hybrid solar cell. CdSe nanorods were fabricated using electrochemical deposition in anodic aluminum oxide (AAO) template. CdSe were deposited from $CdSO_4$ and $H_2SeO_3$ dissolved aqueous solution by direct current electrochemical deposition. Uniformity of CdSe nanorods were dependent on the diameter and the height of holes in AAO. The current density, current mode, bath composition and temperature were controlled to obtained 1:1 atomic composition of CdSe. CdSe electroplating in AAO is bottom-up filling so we applied direct current is better than others for good uniformity of CdSe nanorods. The optimum conditions to obtain 1:1 atomic composition of CdSe nanorods are direct current $10\;mA/cm^2$, 0.25 M $CdSO_4$-5 mM $H_2SeO_3$ electrolytes at room temperature.

• Current Photovoltaic Research
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• v.3 no.1
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• pp.10-15
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• 2015

Cu doping by copper or $Cu_2Te$ materials enhances p+ formation in CdTe near the back contact interface, allowing better formation of ohmic contact. However, the Cu in CdTe junction is also considered as a principal component of CdTe cell degradation. In this paper, Na-doped ZnTe layer was employed as a back contact material to improve the stability of CdTe solar cells. As a process variable, post $CdCl_2$ treatment of CdS/CdTe film was conducted before or after depositing ZnTe:Na on CdTe. The change of the photovoltaic properties of CdTe cells were investigated with aging time. Low-temperature photoluminescence analysis was conducted to describe the degradation mechanism. The result showed that the CdTe solar cells with better stability compare to Cu contact were achieved using an optimized ZnTe:Na back contact.

• Korean Journal of Crystallography
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• v.8 no.2
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• pp.105-110
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• 1997

1μm-CdS films for a window layer of CdS/CuInSe2 solar cell have been prepared by vacuum of 1x10-3 mTorr. Source and substrate temperature ranges were used 800-1100'C and 50-200℃ respectively. Structural, electircal and optical properties of CdS films have been investigated by X-ray diffractometer (XRD), scanning electron microscopy (SSEM), electrical resistivity, the Hall measurement and optical transmission spectra. Electrical resistivity and optical transmission of the CdS films decreased with the increase in CdS source temperature without substrate heating. All the films had hexagonal structure and strong texture with (002) orientation of grain normal to the substrate glass. CdS films evaporated at 1000℃ were the highest electrical conductivity of 0.9(S/cm). Electrical resistivity and optical transmission at the substrate temperature of 100℃ were 40(Ω,cm) and 80% respectively.