• Journal of Crop Science and Biotechnology
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• v.11 no.1
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• pp.17-22
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• 2008

Aromatic rice has become popular owing to its aroma. Growing demand for aromatic rice has spurred interest in the development of domestic cultivars that offer similar combinations of grain attributes such as texture, cooking characteristics, aroma, and taste. In this study, the most important agronomic attributes and aroma of 26 cultivars from Afghanistan, Iran, and Uzbekistan, and controls from Japan, Thailand, and India were characterized. Also $F_2$ populations derived from the cross between(Jasmine 85 aromatic$\times$Nipponbare non-aromatic) and(Jasmine 85$\times$Basmati 370 aromatic) were obtained. Tasting individual grains, cooking test, 1.7% KOH sensory test, and molecular marker analysis have been applied to distinguish between aromatic and non-aromatic rice. Diversity for some traits of agronomic importance, such as plant height was detected among countries, e.g. Afghan cultivars classified as tall, and Iranian and Uzbek intermediate and short, respectively. Differentiations of panicle, grain, leaf, basal internode, and culm dimension among rice cultivars, indicating the source of rice diversity in Central Asia. According to the results, 6 of 10, 2 of 7, and 0 of 6 of Afghan, Iranian, and Uzbek rice cultivars were scored as aromatic, respectively. Therefore, Afghan cultivars are a good source of aromatic rice germplasm for Central Asia. The expression between aromatic and non-aromatic, and aromatic and aromatic combinations has been evaluated. The observed segregation ratio of these crosses in the $F_2$ populations was tested by $x^2$ analysis against the expected ratio for a single gene. A segregation ratio of 3:1 between non-aromatic and aromatic combination has been detected, while segregation has not been detected between the aromatic and aromatic combinations. Also, parallel results were obtained from the tested aromatic rice cultivars. Thus, our results suggest that a single recessive gene controls aroma in all aromatic rice cultivars.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.5
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• pp.545-552
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• 2000

Eight aromatic hydrocarbons were quantified in a newly constructed building before occupancy during the period of November 1997 to January 1998. Air samples were collected in 6 L stainless steel canisters for 8 hours based on working hour. It was found that the measured total concentration of aromatic hydrocarbons decreases rapidly with time up to a steady-state value. However, the fractions for each aromatic hydrocarbon were greatly changed with time. The concentration ratios of indoor to outdoor for aromatic hydrocarbons are greater than 1 during early period of the measurement, and the ratios decrease with time. The concentrations of toluene, m+p-xylene, ethylbenzene, and o-xylene are much higher than those of styrene, 1, 2, 4-trimethylbenzene, and 1, 3, 5-f trimethylbenzene in indoor air. The concentration fractions of m+p-xylene, ethylbenzed, and o-xylene in indoor air are about twice as hight as those in outdoor air measured during the similar period. It was concluded that the aromatic hydrocarbons were emitted from building materials, paints, and adhesives in an-built building.

• Bulletin of the Korean Chemical Society
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• v.16 no.6
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• pp.528-533
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• 1995

Metallic iridium and rhodium powders prepared from the reactions of [M(COD)(PhCN)2]ClO4 (M=Ir(1), Rh(2); COD=1,5-cyclooctadiene) with hydrogen at room temperature in methylene chloride show catalytic activities for hydrogenation of arenes at room temperature under atmospheric pressure of hydrogen. Most substituents (CH3, COOH, NO2, CH2OH, CHO, OPh, OCH3, C=C, halogens and CH2Cl) on aromatic ring suppress the rate of the hydrogenation of the aromatic ring while the aromatic ring hydrogenation of phenol and 1,4-dihydroxobenzene is faster than that of benzene over these metallic powders. Hydrogenation of benzoic acid occurs only at the aromatic ring leaving the COOH group intact over iridium metal powders while benzoic acid is not hydrogenated at all over rhodium metal powders. Carbonyl, nitro, acetylenic and olefinic groups on an aromatic ring are hydrogenated prior to the aromatic ring hydrogenation. Hydrogenolysis of OH groups of phenol, benzyl alcohol and 1,4-dihydroxobenzene, and hydrodehalogenation of halobenzenes, benzyl halides and cinnamyl chloride also occur along with the hydrogenation of aromatic ring.

• Food Science and Preservation
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• v.23 no.5
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• pp.673-679
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• 2016

This study was performed to verify the possibility of manufacturing a germinated aromatic rice tea, which was roasted at 200, 250, and $300^{\circ}C$ each for 10, 20, and 30 min. The roasted aromatic rice was analysed physicochemical properties, sensory characteristics and aromatic compounds. The total polyphenol content and DPPH radical scavenging activities of the germinated aromatic rice increased as the roasting temperature and time increased. Total soluble solid contents, turbidity and browning index of the germinated aromatic rice tea also increased was the roasting temperature and roasting time increased. The pH did not change by roasting. The main aromatic components in roasted germinated aromatic rice tea were 2-methyl butanal, 3-methyl butanal, benzaldehyde and nonanal, which increased according to increasing temperature and time. However, those favorable aroma components were decreased at more than $300^{\circ}C$ of roasting temperature. In addition, methyl benzene, pentanol were increased which affect odor aroma. The sensory score of germinated aromatic rice tea also increased with high roasting temperature and time. However, aromatic rice roasted at a higher temperature ($300^{\circ}C$) showed lower sensory score. Therefore roasting temperature and time must be controlled for manufactureing high quality of germinated aromatic rice tea, and the optimun roasting conditions were $250^{\circ}C$ and 30 min, which provide best physicochemical characteristics of aromatic rice tea.

• Microbiology and Biotechnology Letters
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• v.37 no.4
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• pp.306-315
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• 2009

Due to the depleting petroleum reserve, recurring energy crisis, and global warming, it is necessary to study the development of white biotech-based aromatic chemical feedstock from renewable biomass for replacing petroleum-based one. In particular, the production of aromatic intermediates and derivatives in biosynthetic pathway of aromatic amino acids from glucose might be replaced by the production of petrochemical-based aromatic chemical feedstock including benzene-derived aromatic compounds. In this review, I briefly described the production technology for hydroquinone, catechol, adipic acid, shikimic acid, gallic acid, pyrogallol, vanillin, p-hydroxycinnamic acid, p-hydroxystyrene, p-hydroxybenzoic acid, indigo, and indole 3-acetic acid using metabolic engineering, bioconversion, and chemical process. The problems and possible solutions regarding development of production technology for competitive white biotech-based aromatic compounds were also discussed.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.3
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• pp.106-112
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• 2011

This study is to investigate the effect of an aromatic content in high cetane number (CN) fuels on exhaust emissions under low temperature diesel combustion, which expands the previous research about an aromatic content in low CN fuels. A 1.9L common rail direct injection diesel engine was run at 1500 rpm 2.6 bar BMEP with four fuel sets: an aromatic content of 20% (A20) or 45% (A45) with CN30, i.e. low CN fuels, and CN55, i.e. high CN fuels. Given experimental conditions, the trend of exhaust emissions in high CN fuels was inconsistent with that of low CN fuels which all produced nearly zero smoke but higher NOx for the high aromatic fuel (CN30-A45). For high CN fuels, however, the low aromatic fuel (CN55-A20) produced lower smoke than the high one (CN55-A45) while NOx was similar to each other. The cause of this discrepancy between high CN and low CN fuels is unclear whether it comes from that CN may be a dominant factor to govern exhaust emissions rather than an aromatic content or that the actual CN value of CN55-A45 is lower than CN55-A20. More decent fuel matrix should be prepared and further experiments are needed to confirm it.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1998.10a
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• pp.181-189
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• 1998

In order to investigate the effect of base oil composition on the electronic insulating oil's performances, an experimental study has been conducted using different oils. Owing to their properties, like lower pour point and gas absorbing, naphthenic base oils are used more often than paraffmic base oils for the electronic insulating oil application. Naphthenic and paraffinic base oils are significantly different in their aromatic hydrocarbon content. In this paper, PXE(para xylyl ethane), LAB(linear alkylbenzene), C13 aromatic hydrocarbon mixture and C17 aromatic hydrocarbon mixture are investigated regarding their influence on insulating oil's performances. According to present study, breakdown voltage decreased with increasing aromatic lydrocarbon content in a deep dewaxed paraffmic base oil. However, any changing in the dissipation factor was not recognizable at small treated level. Furthermore, the volume resistance was not influenced by aromatic hydrocarbon content. The gassing tendency was found as a highly sensible property, changing with treating aromatic hydrocarbons. The higher benzene ring content in the hydrocarbon, the better gassing tendency.

• Korean Journal of Plant Resources
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• v.11 no.3
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• pp.279-282
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• 1998

This expriment was carried out to get basic information on composition and yield of aromatic constituents in leaves of four medicinal plants, Angelica tenuissima, Chrysanthemum zawadskii. ssp. latilobum, Artemisia iwayomogi and Artemisia capillaris. Volatile aromatic constituents, 28 compounds in Angelica tenuissima were identified and 19 compounds were indentified in Chrysanthemum zawadskii ssp. latilobum. Volatile aromatic constituents, 23 compounds in Artemisia iwayomogi and Artemisia capillaris were identified. Major volatile aromatic consitiuents analyzed by GC/MS in four plants were $\alpha$-pinene, camphene, sabinene, cis-2-hexanol, and camphor etc. Content of essential oils in Angelica tenuissima, Chrysanthemum zawadskii ssp. latilobum, Artemisia iwayomogi and Artemisia capillaris were 0.014, 0.275, 0.785, and 0.452%, respectively. As a result, it was suggested that a medicinal plant, Artemisia iwayomogi, was worthy of using as a useful material of perfume.

• Journal of Environmental Science International
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• v.12 no.8
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• pp.871-879
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• 2003

The complexation of co-contaminant mixtures between Ag(I) and polycyclic aromatic hydrocarbon (PAH) molecules (naphthalene, pyrene, and perylene) were investigated to quantify the equilibrium constants of their complexes and elucidate the interactions between Ag(I) and PAH molecules. The apparent solubilities of PAHs in aqueous solutions increased with increasing Ag(I) ion concentration. The values, K$_1$ and K$_2$ of equilibrium constants of complexes of Ag(I)-PAHs, were 2.990 and 0.378, 3.615 and 1.261, and 4.034 and 1.255, for naphthalene, pyrene, and perylene, respectively, The K$_1$and K$_2$ values of PAHs for Ag(I) increased in the order of naphthalene ＜ pyrene ＜ perylene and naphthalene ＜ pyrene ≒ perylene, respectively, indicating that a larger size of PAH molecule is likely to have more a richer concentration of electrons on the plane surfaces which can lead to stronger complexes with the Ag(I) ion. For the species of Ag(I)-PAH complexes, a 1:1 Ag(I) : the aromatic complex, AgAr$\^$＋/, was found to be a predominant species over a 2:1 Ag(I) : aromatic complex, Ag$_2$Ar$\^$＋＋/. The PAH molecules with four or more aromatic rings and/or bay regions were observed to have slightly less affinity with the Ag(I) ion than expected, which might result from inhibiting forces such as the spread of aromatic $\pi$ electrons over o wide molecular surface area and the intermolecular electronic repulsion in bay regions.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.1
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• pp.1-9
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• 2009

As many new drug substances contained various aromatic rings and fluorine attached to an electron rich aromatic ring or on the meta-position, a strategy towards improvement in aromatic fluorination of these compounds is highly desirable. The introduction of fluorine-18 onto aromatic rings showed in the limited condition containing electron withdrawing group (EWG) on the para- or ortho-position to get reasonable radiochemical yield so far. No-carrier added (NCA) [$^{18}F$]fluoroarene syntheses by iodonium salts recently reported that has the potential to greatly increase the yield in systems or positions that normally not reactive enough to give sufficient yields in simple model reaction. This review describes the methodological approach towards effective aromatic fluorination by diaryliodonium salts and future prospects in an application of novel PET radiotracer.