• Natural Product Sciences
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• v.5 no.1
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• pp.39-47
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• 1999

The flowers of Alcea rosea L., Malvaceae, sold in the Indian market under the trade name 'Gulkhairo', are well known for their expectorant, cooling and diuretic properties and used in many indigenous cough mixtures in India. The present paper deals with the detailed pharmacognosy of the floral parts including morphological, anatomical, phytochemical and fluorescence characters. Some of the diagnostic features of the drug are : pedicel characterized by multicellular appendages, stellate hairs, rosette crystals of Ca-oxalate, starch sheath and large sized mucilage canals; sepals having distinctive multicellular appendages arranged in a semilunar fashion present adaxially at their base; monadelphous stamens, pollen grains pentaporate provided with dimorphic spines; placentation axile, ovules campylotropous; dark green fluorescence of the powder with nitrocellulose in amyl acetate and yellow fluorescence of trichomes under Fluorescence microscope.

• Journal of Plant Biology
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• v.34 no.1
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• pp.1-8
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• 1991

A sequential sub-cellular study of the epicarp of Nerium indicum has been performed. Outer epidermis of the ovary wall is covered externally with a thin cuticle. Cytoplasm possesses most of the cell organelles in the ovary stage itself. Outermost zone of the pericarp is the epicarp, developing from the outer epidermis. In the developing fruit, cell organelles are found with its maximum intensity. In mature fruit, the epicarp becomes multilayered due to additional development of few collenchymatous cells close to the outermost layer. Epicarpic cell possesses large central vacuole, around which a thin layer of cytoplasm is present. Number of cell organelles are considerably reduced in the mature fruit. In the ovary stage starch grains are electron transparent, while in the mature fruit it is fruit it is electron transluscent.

• Applied Microscopy
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• v.25 no.4
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• pp.71-82
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• 1995

The ultrastructure and storage reserves of the Capsicum annuum seeds were studied in order to identify structure and to localize storage components in the endosperm using light microscopy, scanning and transmission electron microscopy. The seed coat was composed of one cell layer which contained a large number of lipid bodies, while most of the endosperm cells did not showed many lipid bodies. During seed maturation, the endosperm cells were continuously degenerated by the autophagy. Various types of plastids were also distinguished in the endosperm cells. They contained starch grains surrounded by electron-dense tiny particles, plastoglobuli, and vasicular bodies.

• Transactions of Materials Processing
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• v.13 no.1
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• pp.27-32
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• 2004

Thermomechanical behavior of Al-Mg-Si alloys was studied to investigate the effect of microstructural features such as pre-existing substructure and distribution of particles on the deformation characteristics. The controlled compression tests were carried out to get the information on how the alloy responds to temperature, strain amount and strain rate. Then hot forging of Al-Mg-Si alloys carried out and analyzed by the comparison with the compression tests. Microstructural features after forging were discussed in terms of the thermomechanical response of Al-Mg-Si alloys. As already well mentioned, we found that the deformation of Al-Mg-Si at the elevated temperature brought the recovered structure on most conditions. In a certain time, however, abnormally large grains were found as a result of deformation assisted grain growth, which means that hot forging of Al-Mg-Si alloys could lead to a undesirable microstructural variation and the consequent mechanical properties such as fatigue strength.

• Journal of The Korean Astronomical Society
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• v.49 no.4
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• pp.127-136
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• 2016

We investigate optical properties of amorphous alumina (Al2O3) dust grains in the envelopes around O-rich asymptotic giant branch (AGB) stars using laboratory measured optical data. We derive the optical constants of amorphous alumina over a wide wavelength range that satisfy the Kramers-Kronig relation and reproduce the laboratory data. Using the amorphous alumina and silicate dust, we compare the radiative transfer model results with the observed spectral energy distributions. Comparing the theoretical models with observations on various IR two-color diagrams for a large sample of O-rich AGB stars, we find that the amorphous alumina dust (about 10-40%) mixed with amorphous silicate better models the observed points for the O-rich AGB stars with thin dust envelopes.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.55.4-56
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• 2017

Complex organic molecules (COMs) are commonly detected in star forming regions and considered important species since they are seeds of prebiotic molecules. Although COMs form in ice mantles on dust grains, they are preferentially detected in the gas phase. The origin of the gaseous COMs highly depends on the circumstance of each star forming region. Therefore, the distribution of COMs emission reflects the physical and chemical conditions of the region. We present the newly detected COMs, especially methanol emission lines toward two massive star forming regions, G19.61-0.23 and G75.78+0.34 in the Atacama Large Millimeter/submillimeter Array Band 3 observations during the Cycle 2 phase. Multiple transitions of methanol are detected in both regions but show different emission morphology. The origin of the desorption (e.g. shocks or high energy photons) is discussed.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.4
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• pp.141-144
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• 2005

[ $(Y_{0.5}Sm_{0.25}Nd_{0.25})Ba_2Cu_3O_y$ ] [(YSN)-123] high $T_c$ composite superconductors with $CeO_2$ addition were systematically investigated by top seeded melt growth (TSMG) process in air atmosphere. A melt textured $NdBa_2Cu_3O_y$ (Nd-123) single crystal was used as a seed for achieving the c-axis alignment large grains perpendicular to the surface of (YSN)-123 composite oxides. The size of $(Y_{0.5}Sm_{0.25}Nd_{0.25})_2BaCuO_5$ [(YSN)211] nonsuperconducting inclusions of the melt textured (YSN)-123 samples with $CeO_2$ addition were remarkably reduced and uniformly distributed within the (YSN)123 superconducting matrix except in the region very close to the Nd-123 seed crystal. The sample showed a sharp superconducting transition of 91 K.

• Journal of Korea Association of Health Promotion
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• v.3 no.1
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• pp.13-23
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• 2005

In Korea, there is an urgent need to identify nutrition-related risk factors for obesity, because the prevalence of these conditions continues to rise among Koreans. While some studies suggest that westernized dietary pattern may increase the risk of obesity, others do not support these findings. Longitudinal studies examined the role of dietary patterns in relation to changes in body fat composition. Nowadays rapid changes in dietary patterns are related to socioeconomic status and westernized diet. Major dietary changes include a large increase in the consuming of at in the diet and a fall in total cereal intakes and fiber. This research showed remarkable decline in the consuming proportion of the grains and vegetables. These results fit closely with the trend toward increased prevalence of obesity in Korea. Most longitudinal studies on these relationships among children and adults showed that the dietary patterns affected obesity. In conclusion, we need programs to promote healthy Korean diet pattern in Korea.

• Applied Microscopy
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• v.27 no.4
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• pp.473-481
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• 1997

Disorder-order transformation of nanocrystalline FeAl have been investigated by a combination of electron and X-ray diffraction analysis including high resolution electron microscopy and differential scanning calorimetry. Fe-50at.%Al powders mechanically alloyed for 90 hours consist of $5\sim10$ nm size grains haying either disordered b.c.c. structure or amorphous structure. X-ray and electron diffraction of mechanically alloyed FeAl powders show that disorder-order transformation occurs at the temperature range of $300^{\circ}C\sim320^{\circ}C$. Such a low-temperature ordering behavior exhibiting an exothermic reaction is attributable to the nm-scale grain structure with a large amount of defects accumulated during mechanical alloying process.

• Laser Solutions
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• v.13 no.1
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• pp.6-10
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• 2010

Crystallization of 100 nm thick amorphous silicon (a-Si) films on glass substrates was carried out by using a double laser irradiation method. Depending on a-Si deposition method or glass types, the quality of crystallized silicon film varies significantly. For a-Si films deposited with high concentration of impurities, large grains or high crystallinity can not be achieved. Crystallization with different a-Si deposition methods confirmed that for the polycrystallization of a-Si films on glass substrates, controlling the impurity density during substrate preparation is critical.