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Analysis of volatile components in herbal pair (HP) herba schizonepetae-ramulus cinnamomi (HS-RC), single herb HS and RC was carried out by gas chromatography-mass spectrometry (GC-MS) data and chemometric resolution method (CRM). The two-dimensional data obtained from GC-MS instruments were resolved into a pure chromatogram and a mass spectrum of each chemical compound by CRM. In total, 47, 61 and 51 chemical components in volatile oil of HS, RC, and HP HS-RC were respectively determined qualitatively and quantitatively, accounting for 90.52%, 88.37%, and 88.72% total contents of volatile oil of HS, RC, and HP HS-RC, respectively. The number of the volatile components of HP HS-RC is almost the addition of that of two single herbs, but their relative contents are changed. 相似文献
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Volatile oil was extracted from Illicium Verum Hook. f. by using steam distillation. 41 kinds of compounds were separated and identified by GC/MS, and their relative contents were
determined by normalization method. Among 41 identified compounds, there are 14 hydrocarbon components and 22 oxygenated hydrocarbon
derivatives, and a small amount of nitrogenous compounds. The main component is anethole, accounting for 76.23%, and the other
components such as anisyl acetone, anisaldehyde, p-allylanisole, p-cumic aldehyde and p-allylpen take up more than 10%.
Foundation item: Science Foundation of Education for Hunan Province (No. 00C324)
Biography of the first author: YAN Jian-hui, associate professor, doctorate candidate, born in 1958, majoring in applied chemistry. 相似文献
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Gas chromatography-mass spectrometry (GC-MS) and the chemometric resolution method (alternative moving window factor analysis,
AMWFA) were used for comparative analysis of volatile constituents in herbal pair (HP) flos lonicerae-caulis lonicerae (FL-CL) and its single herbs. The temperature-programmed retention index (PTRI) was also employed for the identification
of compounds. In total, 44, 39, and 50 volatile chemical components in volatile oil of FL, CL and HP FL-CL were separately
determined qualitatively and quantitatively, accounting for 87.22%, 94.54% and 90.08% total contents of volatile oil of FL,
CL and HP FL-CL, respectively. The results show that there are 32 common volatile constituents between HP FL-CL and single
herb FL, 33 common volatile constituents between HP FL-CL and single herb CL, and 10 new constituents in the volatile oil
of HP FL-CL. 相似文献
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Originated in the early 1990s, SCGM(1,m)c model has enjoyed widespread application in the fields of urban planning, society economy prediction and modal control in
recent years. However, none of these applications have taken account of time-lag effects in the modeling process. Aiming at
overcoming the defect, the authors introduced time-lag items into SCGM(1,m)c model and developed a SCGM(1,m)c model with time-lag, then discusses in detail some principal problems in the model, such as parameters estimation, model
verifying, model prediction, etc. The model was used on a real slope monitoring project and compared with the conventional
SCGM(1,m)c model. The results show an improvement of average models precision from 1.321 to 0.238 and total average of relative prediction
errors from 12.41% to 7.98% when the modeling data length ranges from 29 to 48 in the slope monitoring case.
Foundation item: The National Natural Science Foundation of China(No. 49774209)
Biography of the first author: LI Zhi-wei, doctoral student, born in Aug. 1974, majoring in surveying data processing, synthetic aperture radar interferometry. 相似文献
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AIN powders were prepared by in-situ synthesis technique. It is a reaction of binary molten Al−Mg alloys with highly pure nitrogen. It was confirmed through thermodynamics
calculation that Mg element in Al−Mg alloys can decrease oxygen content in the reacting system. Thus, nitridation reaction
can be performed to form AIN. Moreover, an analysis of kinetics shows that the nitridation reaction of Al−Mg alloys can be
accelerated and transferred rapidly with the increment of Mg content. 相似文献
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The gene sod in Acidithiobacillus ferrooxidans may play a crucial role in its tolerance to the extremely acidic, toxic and oxidative environment of bioleaching. For insight
into the anti-toxic mechanism of the bacteria, a three-dimensional (3D) molecular structure of the protein encoded by this
gene was built by homology modeling techniques, refined by molecular dynamics simulations, assessed by PROFILE-3D and PROSTAT
programs and its key residues were further detected by evolutionary trace analysis. Through these procedures, some trace residues
were identified and spatially clustered. Among them, the residues of Asn38, Gly103 and Glu161 are randomly scattered throughout
the mapped structure; interestingly, the other residues are all distinctly clustered in a subgroup near Fe atom. From these
results, this gene can be confirmed at 3D level to encode the Fe-depending superoxide dismutase and subsequently play an anti-toxic
role. Furthermore, the detected key residues around Fe binding site can be conjectured to be directly responsible for Fe binding
and catalytic function.
Foundation item: Project(2004CB619201) supported by the National Basic Research Program of China; Project (50321402) supported by the National
Natural Science Foundation of China 相似文献
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By a sequentially selective extraction procedure, polysaccharides (PS) from cyanobacterium Spirulina (Arthrospira) maxima that can be bio-functionally healthy components were fractionated in four parts including the culture medium (PSCM), the
external layers of the cell (PSEL), the cell wall (PSCW) and storage granules (PSSG). The four fractionated parts of polysaccharides
were characterized by gas-liquid chromatography (GLC) equipped with FID and fused-silica capillary column (15 m×0.53 mm i.
d.). The contents of PSCM, PSEL, PSCW and PSSG were about 2.0%, 2.6%, 10.0% and 52.0% to cell dry matter, respectively. Glucose
was almost the only monosaccharide in PSSG and PSCW and most predominant in PSEL, while in PSCM, xylose, rhamnose and glucose
were the main ones. Two uronic acids represented by glucuronic acid and galacturoic acid, six neutral monosaccharides including
fucose, rhamnose, xylose, mannose, galactose and glucose, and two possible unidentified sugars were found in PSEL and PSCM. These data are valuable for the selective productions
of high-added value sugars from Spirulina.
Foundation item: Scholarship for Ph. D at FPMs, Belgium
Biography of the first author: NIE Zhen-yuan, Engineer in biomedicine, born in 1963, majoring in biotechnology and bioengineering. 相似文献