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1.
The chemical components of the essential oils in the barks and leaves of Eucommia ulmoides Oliver were analyzed and compared by chromatograms and mass spectra technique, heuristic evolving latent projections (HELP), alternative moving window factor analysis (AMWFA) algorithms and normalization method based on the peak areas; the flavones in the barks and leaves of Eucommia ulmoides Oliver were separated on an ODS column by gradient elution carried out with the flow phase consisting of water, methanol and phosphoric acid (0.1%), and their contents were quantitatively determined by standard curve method and diode array detection (DAD) at 362 nm. The results show that 68 and 73 compounds respectively from essential oils of the barks and leaves of Eucommia ulmoides Oliver are identified, and there are 33 mutual compounds among 108 compounds determined. The total contents of these volatile components of the two samples possess 92.9% and 97.75% of the gross of the relevant essential oils, respectively; the contents of the rutin, quercetin and kaempferol in the barks and leaves of Eucommia ulmoides Oliver are 0.016 9, 0.003 6, 0.002 1 and 0.064 4, 0.030 2, 0.010 0 mg/g, respectively, and the determination recoveries are 95.2%–106.2%. The comparative analysis shows that for the barks and leaves of Eucommia ulmoides Oliver, there are significant differences in their components of the relevant essential oils and flavones. Foundation item: Project(20235020) supported by the National Natural Science Foundation of China  相似文献   

2.
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, accoun-ting 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%.  相似文献   

3.
    
A new efficient method for preparing o-L-α-glycerylphosphoryl-L-serine was presented. D-α, β-isopropylidene glycerol was phosphorylated with phenylphosphoryl dichloride and the resulting o-D-α,β-isopropylidene glycerylphenylphosphoryl chloride was esterified with N-tert-butoxycarbonyl-L-serine ethyl ester in the presence of pyridine to give acetone L-α-glycerylphenylphosphoryl-N-tert-butoxycarbonyl-L-serine ethyl ester. Finally, the protective groups were removed by two-step hydrolysis while strictly controlling pH value. The reaction to produce (1, 2), (5, 6)-diisopropylidene-D-mannitol, which is the key precursor for the preparation of D-α, β-isopropylidene glycerol, was monitored by using gas chromatography-mass spectrometer in order to obtain an optimum yield of 65%. All compounds were characterized through elemental analysis, infrared spectra, 1H, 13C, 31P-nuclear magnetic resonance spectra and mass spectra. Foundation item: Project (2004018) supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars  相似文献   

4.
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   

5.
The influence of four kinds of Schiff bases on a strain of Escherichia coli was studied by microcalorimetry. Differences in their capabilities of suppressing the metabolism of this bacterium were observed. The results show that the extent and duration of the inhibitory effect on the metabolism as judged from the multiplication rate constant, k, varies with different Schiff bases.The multiplication rate constant k, of Escherichia coli (in log phase) in the presence of Mo-salicylioaldehyde-thiadizole, Mo-piperonaldehyde-thiosemicarbazone and Mo-3-methoxy-salicylicaldehyde-thiadizole decreases with the increase of concentrations of compounds c, and the relationships between k and c, maximum heat production rate Pm and c, peak time of growth curves tp and c are of linearity. For Mo-6-nitro-pieronalde-thiosemicarbazone, the multiplication rate constant is constant irrespective of variation in concentration. The sequence of antibiotic activity of Schiff base is: Mo-salicylioaldehyde-thiadizole>Mo-3-methoxy-salicylicaldehyde-thiadizole>Mo-piperonaldehyde-thiosemicarbazone> 6-nitro-pieronalde-thiosemicarbazone.  相似文献   

6.
The phosphate solubilizing characteristics of a strain YC, which was isolated from phosphate mines (Hubei, China), were studied in National Botanical Research Institute’s phosphate (NBRIP) growth medium containing tricalcium phosphate (TCP) as sole phosphorus (P) source. The strain YC is identified as Stenotrophomonas maltophilia (S. maltophilia) based upon the results of morphologic, physiological and biochemical characteristics and 16S rRNA sequences analysis. The results show that the strain S. maltophilia YC can solubilize TCP and release soluble P in NBRIP growth medium. A positive correlation between concentration of soluble P and population of the isolate and a negative correlation between concentration of soluble P and pH in the culture medium are observed from statistical analysis results. Moreover, gluconic acid is detected in the culture medium by HPLC analysis. It indicates that the isolate can release gluconic acid during the solubilizing experiment, which causes acidification of the culture medium and then TCP solubilization. S. maltophilia YC has a maximal TCP solubilizing capability when using maltose as carbon source and ammonium nitrate as nitrogen source, respectively, in NBRIP growth medium. Foundation item: Project(2004CB619201) supported by the Major State Basic Research and Development Program of China; Project(Z200515002) supported by the Key Project Foundation of the Education Department of Hubei Province, China; Project(GCP200801) supported by the Open Research Fund of Key Laboratory for Green Chemical Process of Ministry of Education, China; Project(Q200811) supported by the Youths Science Foundation of Wuhan Institute of Technology, China  相似文献   

7.
Strain E1 with resistance to 18 mmol/L cadmium (Cd), isolated from Cd-contaminated soil was identified by morphological observation, biochemical and physiological characterization and 16S rDNA sequence analysis. The resistance to heavy metals Cd, Cu, Co, Mn, Pb, Zn and 12 antibiotics was examined. The ability of removing Cd from solution was studied. The characterizations show that strain E1 is affiliated to Pseudomonas aeruginosa (P. aeruginosa). Strain E1 has high resistance to heavy metals and the order is found to be Cd>Mn>Zn>Cu>Pb>Co in solid media. Strain E1 also exhibits the resistance to 12 antibiotics. Both living and non-living cells of strain E1 can remove Cd from solution, and living cell has better biosorption than non-living cell. Foundation item: Project (50621063) supported by the National Natural Science Foundation of China; Project (2004CB619204) supported by the Major State Basic Research and Development Program of China  相似文献   

8.
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   

9.
Separation of baicalin from Scutellaria Baicalensis Georgi with polyamide was studied. The adsorption isotherm, kinetic equation and desorption law were investigated by static and dynamic adsorption methods. The results show that the kinetic behavior is mainly controlled by the liquid film diffusion process and obeys the Boyd film diffusion equation. Equilibrium data for the adsorption of baicalin are correlated with Freundlich isotherm equation, i.e. q=3.8Ce2.057, suggesting that the relative capacity of polyamide to baicalin is somewhat small. The desorption results indicate that the baicalin with mass fraction of 33.86% and the least impurities can be obtained by chromatography using 60% ethanol as the eluant at room temperature.  相似文献   

10.
In order to solve the citrus peel resource waste problem and minimize the drawbacks of chemical extraction of pectin, a protopectinase-overproducing strain CD-01 for pectin production was isolated from a pit soil dumped with perished orange in Changde City, Hunan Province of China. The strain CD-01 had the same morphology and 28S rRNA gene sequence (FJ184995) as that of Aspergillus niger (ATCC 64028). It was thus identified and named as Aspergillus niger CD-01. The fermentation condition was optimized based on L9(34) orthogonal experimental design and the variances analyses. The results show that the optimal condition for producing pectin is as follows: time 36 h, temperature 35 °C, pH 5, and urea as the nitrogen source. Under this condition, the pectin yield can reach up to 24.5%. This shows a great potential of Aspergillus niger CD-01 in pectin extraction from citrus. Foundation item: Projects(50621063, 50674101) supported by the National Natural Science Foundation of China  相似文献   

11.
Cr(VI)-amended soil was inoculated with Cr(VI)-reducing strain, Bacillus sp. XW-4 and incubated at 28 °C in an incubator. Cr(VI) reduction, available Cr and Cr fraction in soils were studied. The results show that addition of Bacillus sp. XW-4 can promote Cr(VI) reduction, but inoculation of this strain has a negative effect on the decrease of available Cr content in soil. In controls (without this strain) amended with 100 and 200 mg/kg of Cr(VI), Cr(VI) contents decrease to about 41 and 92 mg/kg respectively after incubation of 4 d, while in soil inoculated with XW-4, Cr(VI) contents decrease to about 18 and 60 mg/kg, respectively. The content of available Cr in soils with inoculation of XW-4 is higher than that in controls. Chromium is partitioned into water soluble Cr, exchangeable Cr, precipitated Cr, Cr bound to organics and residual Cr. The highest content of Cr is observed in residual form and water soluble Cr is not detected for all treatments after 42 d, but the soils inoculated with Bacillus sp. XW-4 contain higher content of exchangeable Cr and lower content of precipitated Cr than the soil without the inoculum. Inoculation of Bacillus sp. XW-4 can increase chromium activity in soils. Foundation item: Project(20050532009) supported by the Doctoral Foundation of Ministry of Education of China; Project supported by Program for Changjiang Scholars and Innovative Research Team in University  相似文献   

12.
A heterotrophic acidothermophilic bacterial strain, YNTC-1, was isolated from an acidic hot spring in Tengchong, Yunan, China. YNTC-1 grows at pH value of 1.5-8.0 and temperature of 40-70 ℃, with optimal pH and temperature at 3.0 and 55 ℃, respectively. The cells of the strain are in shape of short rod, with 1.0-1.2 μm in length and 0.7-0.8 μm in diameter, and with distinct spores at both poles of each cell. The predominant fatty acids in cellular membrane of the strain are C18:1 ω7c. 16s rRNA gene analysis reveals that this strain is closely related to Alicyclobacillus sendaiensis, with over 99% sequence similarity. Based on phenotypic and genotypic analyses, YNTC-1 is identified as a member ofA. sendaiensis. Considering some important morphological and biochemical differences between strain YNTC-1 and A. sendaiensis ATCC 27009T, YNTC-1 may be proposed to be a novel subspecies of A. sendaiensis. However, this viewpoint has to be confirmed by further studies. Co-bioleaching of pyrite and chalcopyrite with strain YN22, Sulfobacillus thermosulfidooxidans, shows that strain YNTC-1 has no evident influence on bioleaching rates of these two sulphide minerals.  相似文献   

13.
To reveal the impact of mining on bacterial ecology around mining area, bacterial community and geochemical characteristics about Dabaoshan Mine (Guangdong Province, China) were studied. By amplified ribosomal DNA restriction analysis and phylogenetic analysis, it is found that mining pollution greatly impacts the bacterial ecology and makes the habitat type of polluted environments close to acid mine drainage (AMD) ecology. The polluted environment is acidified so greatly that neutrophil and alkaliphilic microbes are massively dead and decomposed. It provided organic matters that can make Acidiphilium sp. rapidly grow and become the most bacterial species in this niche. Furthermore, Acidithiobacillus ferrooxidans and Leptospirillum sp. are also present in this niche. The amount of Leptospirillum sp. is far more than that of Acidithiobacillus ferrooxidans, which indicates that the concentration of toxic ions is very high. The conclusions of biogeochemical analysis and microbiological monitor are identical. Moreover, because the growth of Acidithiobacillus ferrooxidans and Leptospirillum sp. depends on ferrous iron or inorganic redox sulfur compounds which can be supplied by continual AMD, their presence indicates that AMD still flows into the site. And the area is closer to the outfalls of AMD, their biomasses would be more. So the distinction of their biomasses among different areas can help us to find the effluent route of AMD. Foundation item: Project(50621063) supported by the Science Fund for Creative Research Groups of China; Project(2004CB619201) supported by the Major State Basic Research Development Program of China  相似文献   

14.
By orthodox experiment, the main influence factors of desulfurization by sul folobas of pH value, temperature, coal slurry concentration and coal granularity are studied in detail and the optimal experimental conditions were also obtained. The experimental results demonstrate that sul folobas being kind of linking-heat, acidophilic and self-supported bacterium with double characters can effectively remove inorganic and organic sulfur in coal. The superlatively desulfurization rate is up to 48.57% total sulfur and 41.71% inorganic sulfur within 10 d and its desulfurization rate can be greatly affected by the four factors above mentioned. Therefore, the optimum conditions of desulfurization are obtained by comprehensive experiment and they are as following: pH value 3, temperature 70°C, coal slurry concentration 10% and coal granularity 150 μm, respectively. Moreover, the repetition experimental results confirm that the desulfurization by sul folobas is steady. Foundation item: The National Advanced Technology Research and Development Project (863 Project 2002AA649220) Biography of the first author: HE De-wen, postdoctor, born in April 1968, majoring in solid waste pollution control and resource, environmental assessment and plan.  相似文献   

15.
LetR be ans-unital ring, and we prove a commutativity theorem ofR satisfying the following conditions: (1) For eachx, y εR, there exist bounded positive integersk=k(x,y), s=s(x,y), t=t(x,y) (where, at least one ofk, s, t is not equal to 1) such that (xy)k=x syt, (xy)k+1=x s+1 y t+1; (2)N, the set of all nilpotent elements ofR, isp-torsion free, wherep is the L. C. M. (least common multiple) of allk, s, t. Project supported by The Science Foundation of NECC for Returns Synopsis of the first author Yin Zhiyun, professor, born in May, 1960, study fields are commutative algebras and economical mathematics.  相似文献   

16.
By using thiobacillus ferroxidans (T. f) from Qixiashan, Hubei Province, China, the adsorption characteristics of T. f on surface of sulfide mineral were studied. The influences of adsorption time, pH value, temperature, initial inoculated concentration of bacteria, concentration of sulfide mineral powder, and variety of minerals on the adsorption characteristics were firstly investigated by using the ninhydrin colorimetric method, and the changes of contact angles and Zeta potentials of mineral surface during the bacterial adsorption were then determined. The results show that when the leaching experiments are performed for a long time from several days to a month, the maximal quantity of adsorption of T f on the surface of pyrite is obtained under the following conditions: leaching for 20 d, pH value in range of 1–2 and temperature at 30 °C, respectively; when the bio-leaching experiments are performed for a shorter leaching time, the maximal quantity of adsorption is obtained under the conditions: bio-leaching for 2 h, at 2.4×107 cell/mL of initial inoculated bacteria concentration, and at 10% of mineral powder concentration; and the adsorption quantities are different from one sulfide mineral to another, and the adsorption of T. f on the surface of sulfide minerals includes three phases: increasing phase, stationary phase and decreasing phase. Foundation item: Project(50321402) supported by the National Natural Science Foundation of China; project (2004CB619204) supported by the National Key Fundamental Research and Development Program of China  相似文献   

17.
The stress intensity factorK in the tip of crack which is in the corner of the frame component has been calculated indirectly by means of numeric calculation ofJ Integral. Some laws and relationships among the stress intensity factorK, the applied loads and the crack length for this kind of components have been discovered for the first time. The calculating formula forK has been deduced, the criticalK has been calculated with the formula, that is 5 811.56–6 122.58 MPa · mm1/2. The conclusions reached in this paper are of great referential and practical value for simplifying the calculation of stress intensity factorK for this type of components. Project supported by Technological Development Foundation of the Nonferrous Metal Industry Corporation of China Synopsis of the first author Liu Yilun, Doctor, associate professor, born in Oct. 30, 1955. Research areas are fatigue strength of component and the technology of continuous casting for non-ferrous metal.  相似文献   

18.
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   

19.
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   

20.
Coating of Fe, Ni on α-alumina microspheres by heterogeneous precipitation   总被引:1,自引:0,他引:1  
1INTRODUCTION Themagneticmetal coatedceramicoxides,core shellstructuralcompositematerials,inwhichthinmetallicfilmsarecoatedonaceramicoxide matrixwithmicrometerparticlesizes,areattrac tiveduetothecombinationofthefunctionalchar acteristicsofmetalsandmechanicalpropertiesoftheceramicmatrix.Theceramic basedtransition metal coated,core shellcompositessuchasNi coatedAl2O3[1],Fe coatedAl2O3[2],FeNi coated Al2O3[3]orCoFe coatedSiO2[4],havebeenfoundtoexhibitinterestingfunctionalperformancesdue…  相似文献   

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