• Journal of applied mathematics & informatics
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• v.12 no.1_2
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• pp.281-289
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• 2003

The convection of water is investigated in the vicinity of its density maximum temperature (277 K) in an inclined square cavity in the presence of heat sources. Numerical investigations are carried out by maintaining one of the vertical walls uniformly at 273 K and varying the other wall between temperatures 275 K and 285 K at different inclinations angles. The isotherms, streamlines and velocity profiles reveal the possible existence of multicellular fluid motions, and bidirectional velocity distributions. These fluid flow and heat transfer characteristics are significantly modified by the cavity inclination in the presence of heat sources.

• Solar Energy
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• v.18 no.4
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• pp.39-47
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• 1998

The natural convection heat transfer in a vertical plate with discrete heat sources was studied experimentally. The particular interest was the thermal interaction of the heat sources. In this study, the radiative and conductive heat transfer were considered as heat loss, Thus, the net convective heat transfer rate was presented as adiabatic temperature and thermal wake function. As a results, for non-uniform heating condition, heat input ratio(q1/q2) was most dominant parameter for the thermal wake function. The convective heat transfer rate is decreased with the increasing of channel ratio. For the range of $7.50{\times}10^5<Rac<8.66{\times}10^6$, a useful correlation was proposed as a function of channel Rayleigh number.

• Korean Journal of Microbiology
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• v.7 no.2
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• pp.86-90
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• 1969

1. Amylase producing bacteria have been isolated from natural sources and was identified out. The above strain is identical to Bacillus subtillis in every details of physiological and morphorogical characteristics by this investigations. 2. Sikworm chrysalis nad chlorella extracts are prove to be further effective for the stimulation of amylase production than any other sources. The former silkworm extract is more stronger in its activity. 3. It is found that effective results had been accepted by a less soybean meal addition per that of wheat bran in the mixture ratio of them, also less addition of corn is needed in the mixture ratio of between corn and whear bran. In the mixing ratio of wheat bran per silkworm or chlorella extracts, the addition of wheat bran is necessary for stimulation of amylase production. 4. Fro the stimulation of amylase production, the effective substances from natural sources and its order of activity in cultral media cultral media is proved as follows, silkworms ext.>chlorella ext.>alcohol>skim-milk and peptone>fermented milk>radish leaf ext.

• The Korean Journal of Mycology
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• v.23 no.3 s.74
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• pp.275-283
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• 1995

The nutritional requirements of mycelial growth for Pleurotus spp. were studied. As the carbon sources, soluble starch and dextrin, nitrogen sources, arginine and ammonium tartrate, and calcium sources, $CaCO_3$ enhanced mycelial growth. Optimum C/N ratio was 100 : 1. On the base of results from the experiment on nutritional requirements, the following receipe is suggested for growth of Pleurotus spp.; starch 15 g, arginine 3.484 g, ammonium tartrate 3.06 g, $CaCO_3$ 0.314 g, $KH_2PO_4$ 8.138 g, $K_2HPO_4$ 1.584 g, $MgSO_4{\cdot}7H_2O$ 1.5 g for P. sajor-caju and 2.5 g for P. ostreatus. $FeSO_4{\cdot}7H_2O$ 0.02 g, $ZnSO_4{\cdot}7H_2O$ 0.03 g, $MnSO_4{\cdot}7H_2O$ 0.02 g, optimum pH 6.0. This new synthetic medium is tentatively designated as Park's medium.

• Journal of Pharmacopuncture
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• v.25 no.4
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• pp.317-325
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• 2022

Polymers are the major constructive material of pharmaceutical formulations that play a prime role in designing effective drug-delivery systems and releasing drugs at their sites of application. Polymers are composed of multiple repeating units of high molecular mass components with attendant properties. Most synthetic polymers are non-biocompatible, expensive, and extremely inclined to deliver adverse impacts. Meanwhile, edible polymers obtained from natural sources have gained remarkable recognition for their promising use in modern medicine. Moreover, polymers derived from natural sources are generally preferred due to certain of their unique features such as abundant availability, biocompatibility, nontoxicity, economical, safe, and effective functions that fit the purpose. Polysaccharides including starch, cellulose, hemicellulose, pectin, and mucilage are identified as a major class of naturally obtained molecules that have a substantial role as functional polymers. This review summarizes the potential role of polysaccharides derived from vegetable sources such as adhesives, anticaking agents, binders, disintegrants, emulsifiers, film-framing agents, and thickeners. This is simply an opportunity to abandon synthetic excipients that hurt our bodies and think back to nature from where we originate.

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.651-660
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• 2006

Natural products are a rich source of biologically active small molecules and a fertile area for lead discovery of new drugs [10, 52]. For instance, 5% of the 1,031 new chemical entities approved as drugs by the US Food and Drug Administration (FDA) were natural products between 1981 and 2002, and another 23% were natural product-derived molecules [53]. These molecules have evolved through millions of years of natural selection to interact with biomolecules in the cells or organisms and offer unrivaled chemical and structural diversity [14, 37]. Nonetheless, a large percentage of nature remains unexplored, in particular, in the marine and microbial environments. Therefore, natural products are still major valuable sources of innovative therapeutic agents for human diseases. However, even when a natural product is found to exhibit biological activity, the cellular target and mode of action of the compound are mostly mysterious. This is also true of many natural products that are currently under clinical trials or have already been approved as clinical drugs [11]. The lack of information on a definitive cellular target for a biologically active natural product prevents the rational design and development of more potent therapeutics. Therefore, there is a great need for new techniques to expedite the rapid identification and validation of cellular targets for biologically active natural products. Chemical genomics is a new integrated research engine toward functional studies of genome and drug discovery [40, 69]. The identification and validation of cellular receptors of biologically active small molecules is one of the key goals of the discipline. This eventually facilitates subsequent rational drug design, and provides valuable information on the receptors in cellular processes. Indeed, several biologically crucial proteins have already been identified as targets for natural products using chemical genomics approach (Table 1). Herein, the representative case studies of chemical genomics using natural products derived from microbes, marine sources, and plants will be introduced.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.1
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• pp.42-50
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• 2009

Samples of subway dust were collected by the air filter system of 30 subway stations on Daegu subway line 1 in January 2008. Samples were sieved below 100 ${\mu}m$, and 14 elements were analyzed using ICP after acid extraction. Results obtained from the source assessment of trace elements using enrichment factor showed that Ca, Fe, K, Mg, Mn, Na, V were influenced by natural sources such as weathered rock and resuspended soil, while Cd, Cr, Cu, Ni, Pb and Zn were influenced by anthropogenic sources such as fuel combustion and waste incineration. Concentrations were remarkably higher in components from natural sources than in components from anthropogenic sources. Anthropogenic sources were significantly affected by indoor dusts than outdoor dusts. Results of pollution indices of heavy metals indicated that indoor dusts were more contaminated with heavy metal ions than outdoor dusts. The correlation analysis among trace elements indicated that components were much correlated in the order of natural sources-anthropogenic sources, anthropogenic sources-anthropogenic sources, natural sources-natural sources in both indoor and outdoor dusts. Trace element components of outdoor dusts were largely correlated than those of indoor dusts. In addition, indoor dusts were significantly affected by outdoor dusts rather than depth from the surface or the average daily number of subway passengers.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.5
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• pp.619-627
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• 2000

Historically, dyed textiles were symbols of status and, because of their expense, reserved only for people of wealth and specalist, Early dye sources probably included plant, animal and mineral extracts. As synthetic dyes have been developed, beginning with synthetic indigo in 1897, reliance on natural dye sources diminished. But renewed interest in natural dyes is fueled by a pro-environment consumer aware of the ecological liabilities of the dye industry. Han Jee was imported from China where it was influenced to period of the three kingdoms(Silla, Baekje, Kokuryo). After that, Han Jee was used for paper in old Korea for long thime before paper was came with civilization. In this paper, dyeing of Han Jee with loess were investigated according to dyeing temperature, dyeing time, loess concentration, and effects of additives. As a reuslts, λmax of Han Jee dyed by loess was 710nm. ΔE values of Han Jee increased by loess concentration, dyeing time, dyeing temperature. Dyeing with additives treatment increased dyeability. Especially, Han Jee treated with aluminium acetate shows the largest dyeability of the Han Jee. The Han Jee dyed loess had very good lightfastness.

• Journal of Microbiology and Biotechnology
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• v.7 no.4
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• pp.278-281
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• 1997

Streptomyces sp. MCY-846 selected by in vitro cytotoxicity assay produced elaiophylin. Individual characteristics of the strains such as spore morphology, and physiological characteristics indicated that the strain is resembled to Streptomyces hygroscopicus. The time course of cell growth and antibiotic production was observed in the medium containing 0.5% trehalose and 0.5% soybean meal as carbon and nitrogen sources, respectively. The optimum production of elaiophylin was tested with different combinations of carbon and nitrogen sources and reached a maxima of $470{\mu}$/ml in the PC-II medium.

• Korean Journal of Pharmacognosy
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• v.17 no.1
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• pp.19-22
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• 1986

As a continuation of the previous work, a second group of sixty solvent fractions prepared from twenty plant species were screened for their inhibitory effects on adenosine 5'-diphosphate (ADP)-, arachidonic acid (AA)- or collagen-induced rat platelet aggregation. The results suggested that five plant species including Angelica koreana, Cassia obtusifolia, Gastrodia elata, Paeonia lactiflora and Salvia miltiorrhiza are potential sources of inhibitors of platelet aggregation.