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201.
The solvatochromic behavior of indonaphthol dye was described. The UV/Vis absorption spectra of this compound have been studied
in 5 solvents of different polarity. The solvatochromism of indonaphthol dye is discussed with the aid of semiempirical calculations. 相似文献
202.
Synthesis and application of alkyl-substituted disazo yellow dyes for unmodified polypropylene fiber
Taekyeong Kim Jongsuc Jung Songi Son Seokhan Yoon Mikyung Kim Jin-Seok Bae 《Fibers and Polymers》2008,9(5):538-543
The several disazo dyes having different alkyl substituents were synthesized to dye unmodified polypropylene fiber. The affinity
of the dyes onto unmodified polypropylene was increased with the increase of the length of alkyl substituents. Therefore,
the heptyl-substituted dye having the longest alkyl group in this experiment showed very high color strength of dyeings with
K/S value of over 24 at maximum absorption wavelength. The color fastnesses to washing, rubbing and light were also improved
significantly for the longer alkyl substituted dyes, so that the heptyl-substituted dye exhibited a rating of 4∼5 for all
kinds of fastnesses. 相似文献
203.
Molecular mapping of a new genic male-sterility gene causing chalky endosperm in rice ( Oryza sativa L.) 总被引:11,自引:0,他引:11
A genic male-sterility gene newly induced by chemical mutagenesis, tentatively designated as ms-h(t), was located on the molecular
map of rice and tested for its effect on chalky endosperm. Bulked segregant analysis was used to determine the chromosomal
location of the ms-h(t) locus by screening four to five RFLP markers per chromosome. After confirming that the gene was located
on chromosome 9, twenty-four RFLP markers from chromosome 9 were surveyed for polymorphism in the parents of the mapping population.
Of these, eleven markers were mapped around the ms- h(t) locus. RG451 and RZ404 flanked the ms-h(t) gene, at 2.5cM and 3.3cM,
respectively. Heterozygous F2 to F4 progenies were tested for co- segregation of male-sterility and chalky endosperm and it
was revealed that ms-h(t) might have a pleiotropic effect on chalky endosperm. This mutant would be a good biological material
to characterize the biochemical mechanism of male sterility and related pleiotropic effects. Further studies should be needed
to know the usefulness of this mutant for hybrid seed production.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
204.
Long-term efficacy of aroma microcapsules on natural indigo-dyed cotton fabric was evaluated by objective and subjective tests. The fixation of aroma microcapsules was carried out by pad-dry-cure process on dyed cotton fabric. Mercerized cotton fabric was dyed with natural indigo obtained from Polygonum tintorium (via the modified Niram method) and subsequently padded with melamine-formaldehyde microcapsules containing aroma essential oil (natural source of a Chinese arborvitae 20-25 %). Softener was applied in the same (one-step) or sequential (two-step) padding bath. We confirmed that microcapsules were fixed on cotton fibers by SEM analysis. The addition of softener was not much effective for the fabric performances on softness or air permeability. All the colorfastness ratings were above 4/5 and the color difference was within the acceptable range of 1.62-2.08. The efficacy of fabric samples stored for 2 years was evaluated using the GC/MS-headspace technique and the samples stored for 0.5, 1.5, and 2.5 years were also evaluated in terms of aroma release by the human perception test. Bornyl acetate was confirmed as the main component of essential oil, which was continuously released by the microcapsule-treated fabric (D/MC) during storage for more than 2 years. In durability and human perception tests, the microcapsules on the cotton fabric were stable to laundering, rubbing, ironing, and light. 相似文献
205.
A-Young Shin Hyi-Seung Lee Yeon-Ju Lee Jong Seok Lee Arang Son Changhoon Choi Jihoon Lee 《Marine drugs》2020,18(12)
A total of eight new oxygenated 4-exo-methylene sterols, 1–8, together with one artifact 9 and six known sterols 11–16, were isolated from the marine sponge Theonella swinhoei collected from the Bohol province in Philippines. Structures of sterols 1–8 were determined from 1D and 2D NMR data. Among the sterols, 8α-hydroxytheonellasterol (4) spontaneously underwent an allylic 1,3-hydroxyl shift to produce 15α-hydroxytheonellasterol (9) as an artifact; this was rationalized by quantum mechanical calculations of the transition state. In addition, the 1,2-epoxy alcohol subunit of 8α-hydroxy-14,15-β-epoxytheonellasterol (5) was assigned using the Gauge-Independent Atomic Orbital (GIAO) NMR chemical shift calculations and subsequent DP4+ analysis. Finally, comparison of the 13C chemical shifts of isolated 7α-hydroxytheonellasterol (6) with the reported values revealed significant discrepancies at C-6, C-7, C-8, and C-14, leading to reassignment of the C-7 stereochemistry in the known structure. 相似文献
206.
Nguyen Minh Phuong Yumei Kang Katsutoshi Sakurai Kōzō Iwasaki Chu Ngoc Kien Nguyen Van Noi Le Thanh Son 《Water, air, and soil pollution》2010,207(1-4):319-332
Levels and chemical forms of heavy metals in forest, paddy, and upland field soils from the Red River Delta, Vietnam were examined. Forest soils contained high Cr and Cu levels that were higher in subsurface than in surface layers. Levels of Cu, Pb, and Zn that exceeded the limits allowed for Vietnamese agricultural soils were found in the surface layer of a paddy field near the wastewater channel of a copper casting village. High amounts of Zn accumulated in the surface soil of paddy fields close to a fertilizer factory and an industrial zone. In these cases, larger proportions of Cu, Pb, and Zn were found in the exchangeable and acid-soluble fractions compared to the low-metal soils. We conclude that no serious, large-scale heavy metal pollution exists in the Red River Delta. However, there are point pollutions caused by industrial activities and natural sources. 相似文献
207.
Effect of dietary taurine levels on the conjugated bile acid composition and growth of juvenile Korean rockfish Sebastes schlegeli (Hilgendorf)
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Shin‐Kwon Kim Kyoung‐Gil Kim Kyoung‐Duck Kim Kang‐Woong Kim Maeng‐Hyun Son Michael Rust Ronald Johnson 《Aquaculture Research》2015,46(11):2768-2775
This study was conducted to investigate the effects of different taurine levels on the conjugated bile acid composition and growth of juvenile rockfish. Five taurine level diets were made by the supplementation of taurine (0%, 0.5%, 1.0%, 1.5% and 2.0%) to a basal diet. Fish meal washed with 70% ethanol to exclude taurine was used for the sole protein source. Feeding experiments were accomplished at 15°C using juvenile fish (initial BW: 13.5 g). Fish were fed the experimental diets for 4 months. At the end of experiments, fish were weighed and stored at ?80°C for analysis of free amino acids and conjugated bile acids contents. The growth performance and feed efficiency of Korean rockfish were improved by taurine supplementation in the experimental diets. The taurine contents of the whole body increased with the increase in the taurine supplementation. The primary conjugated bile acids in gall bladder were taurocholic acid (83.5–165.6 mg mL?1) and taurochenodeoxycholic acid (6.3–20.0 mg mL?1). Total bile acids increased with increases in dietary taurine. Taurocholic acid content was more than 95% of the total conjugated bile acids. This indicates that taurine is the sole amino acid to make conjugated bile acid in Korean rockfish. Dietary taurine levels improved the conjugated bile acid composition in juvenile Korean rockfish. 相似文献
208.
H.C. Kwon S.H. Choi Y.U. Kim S.O. Son J.Y. Kwon 《Fish physiology and biochemistry》2003,28(1-4):351-352
Immature eels positively responded to estradiol-17β (E2) injection in terms of vitellogenin (Vg) synthesis but not to growth hormone (GH) or 17α-methyltestosterone (MT) injection. However, injection of MT or GH combined with E2 strongly increased Vg synthesis. In in vitro experiments, eel hepatocytes treated with E2, GH, or MT alone did not produce detectable amount of Vg, whereas the combination of E2 with GH or MT, or both greatly increased Vg synthesis in the hepatocytes. 相似文献
209.
Previously we described the development of an attenuated Pasteurella multocida mutant that expresses only the N-terminal truncated fragment of P. multocida toxin (N-PMT) and its protective effects in a mouse model. This paper details our evaluation of the vaccine potential of this mutant strain in pigs. Pigs vaccinated with the mutant showed significantly higher rates of antibody induction and lower nasal conchal (turbinate) scores for atrophic rhinitis than controls, which suggests that this mutant strain may be a good candidate for a live attenuated vaccine. 相似文献
210.
Kien Chu Ngoc Noi Van Nguyen Bang Nguyen Dinh Son Le Thanh Sota Tanaka Yumei Kang Katsutoshi Sakurai Kōzō Iwasaki 《Water, air, and soil pollution》2009,197(1-4):75-89
This study assessed the arsenic and heavy metal contaminations of agricultural soils around the tin and tungsten mining areas in Dai Tu district in northern Vietnam. Among the examined elements, high total contents of As and Cu were found in the agricultural fields at both tin and tungsten mining sites. Although the major part of the accumulated As and Cu were bound by various soil constituents such as Fe and Mn oxides, organic matter, and clay minerals, increases in water soluble As and Cu were observed, especially for the paddy fields. The results suggest that, in the studied area, As and Cu dispersion from their pollution sources into farmlands is mainly via fluvial transportation of mine waste through streams that cross the paddy fields around the tin mining area, and soil erosion at the tea fields located at lower positions of the slope in the tungsten mining area. 相似文献