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Water-distilled essential oil from Ononis viscosa L. subsp. breviflora (DC.) Nyman was analyzed by GC/MS. Forty compounds were characterized representing 81.3% of the oil. Hexahydrofarnesylacetone (12.5%), carvacrol (10.0%), lauric acid (8.3%), nonanal (5.5%), E-geranylacetone (4.8%), and dodecanal (4.8%) were identified as the major constituents. 相似文献
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In this paper the applicability of an in situ ultrasonic diagnostic technique in understanding the formation process of zeolite X with a novel morphology was demonstrated. The complexity of the starting fly ash feedstock demands independent studies of the formation process for each type of zeolite since it is not known whether the crystallization mechanism will always follow the expected reaction pathway. The hierarchical zeolite X was noted to follow a solution phase-mediated crystallization mechanism which differs from earlier studies of the zeolite A formation process from unaged, clear solution extracted from fused fly ash. The use of the in situ ultrasonic monitoring system provided sufficient data points which enabled closer estimation of the time of transition from the nucleation to the crystal growth step. In order to evaluate the effect of temperature on the resulting in situ attenuation signal, synthesis at three higher temperatures (80, 90 and 94 °C) was investigated. It was shown, by the shift of the US-attenuation signal, that faster crystallization occurred when higher temperatures were applied. The novel hierarchical zeolite X was comprised of intergrown disc-like platelets. It was further observed that there was preferential growth of the disc-shaped platelets of zeolite X crystals in one dimension as the synthesis temperature was increased, allowing tailoring of the hierarchical morphology. 相似文献
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Z. Tunalier M. Kosar N. Ozturk K. H. C. Baser H. Duman N. Kirimer 《Chemistry of Natural Compounds》2004,40(3):206-210
The antioxidant properties and phenolic composition of 27 Sideritis species were studied. Plant samples were extracted with petroleum ether using a Soxhlet apparatus. The defatted plant materials were extracted with 70% methanol. Antioxidant activities of the extracts were measured using Fe+2 induced linoleic acid peroxidation, as indicated by thiobarbituric acid reactive substance (TBARS) production. Free radical scavenging activities were determined based on 1,1-diphenyl-2-picrylhydrazyl radical (DPPH). Results were compared with standard BHT. Total phenol concentration of the extracts was estimated with Folin-Ciocalteu reagent using gallic acid as standard, and phenolic components were quantified by HPLC-DAD. 相似文献
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Baser KH Demirci B Iscan G Hashimoto T Demirci F Noma Y Asakawa Y 《Chemical & pharmaceutical bulletin》2006,54(2):222-225
The essential oil of aerial parts, leaves and flowers of the endemic Anthemis aciphylla BOISS. var. discoidea BOISS. (Asteraceae) were obtained by hydrodistillation. The oils were analyzed both by GC and GC-MS on a polar column. The monoterpenes alpha-pinene (9-49%) and terpinen-4-ol (22-32%) were characterized as the main constituents. An unknown component isolated from the essential oil was characterized by means of MS, HR-MS, FT-IR, 1D- and 2D-NMR techniques as isofaurinone (1). Furthermore, the biological activity of the essential oils was evaluated in various human pathogenic microorganisms using the broth microdilution method. Weak to moderate inhibitions (0.06-1.0 mg/ml) was observed. 相似文献
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Water-distilled essential oil fromAjuga bombycina,endemic in Turkey, was analyzed by GC/MS. Fifty-four compounds were characterized representing 96.2% of the oil with-pinene (28.2%),-pinene (18.5%), germacrene D (8.5%), and-phellandrene + limonene (6.9%) as the major constituents 相似文献