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1.
Mono-, di-, and triethylene glycol are chemicals used in various industrial (polyester products, plasticizers, printing, etc.) and domestic settings. The toxicity of these compounds is relatively low, but they do pose risks to the environment. Phytoremediation of the three glycols by Echinodorus cordifolius L. Griseb. were studied. The glycols were degraded in the leaves and roots, but leaves were the main source of degradation. The results of this study indicate that the plant can degrade triethylene glycol to diethylene glycol, diethylene glycol to 1,4-dioxan-2-one, or even further to monoethylene glycol. Moreover, 2-methoxy-4-vinylphenol, 1,2-cyclopentanedione, 1,4:3,6-dianhydro-.alpha.-d-glucopyranose, 2-propenamide, and 2,5-anhydro-1,6-dideoxyhexo-3,4-diulose were produced by this plant in response to the glycols.  相似文献   

2.
Improved diethylene glycol distearate embedding wax   总被引:1,自引:0,他引:1  
Diethylene glycol distearate wax and cellulose caprate resin, 4:1 respectively by weight, were melted together at 75 C for five hours with occasional stirring. The resin tempered the extreme brittleness of the wax without softening it, and raised the melting point only one degree to 50 C. Fixed plant tissues were dehydrated in ethanol, cleared in xylene, and infiltrated with wax. Modified diethylene glycol distearate was easier to trim and shape, and formed flat sections more consistently than the pure wax. Sections were cut singly on Ralph knives with attached water pools on an ultramicrotome. Sectionability was excellent at 2-3 micrometers, variable at 1.0 micrometer, but impossible at 0.5 micrometer. Sections were transferred onto water drops on slides, dried, dewaxed, stained, and coverglasses applied as in the paraffin method. Histological feature of plant tissues were much sharper in modified diethylene glycol distearate sections than in paraffin sections, and were similar to plastic sections.  相似文献   

3.
4.
The polymerization of dimethyl terephthalate and diethylene glycol by enzymic catalysis in toluene is described. The potential pi-pi interactions of the aromatic rings together with the relative flexibility of the diol segment have been regarded as synergy factors responsible for the formation of a pure cyclic compound. The so-called C2 macrocycle was characterized by (1)H and (13)C NMR, size-exclusion chromatography, differential scanning calorimetry, mass spectrometry, and X-ray diffraction on powder. Structurally speaking, it is made of two repeating units. The substitution of the central oxygen atom of the diol by -CH(2)- or -S- as well as the presence of ortho-substituents (-NH(2) or -NO(2)) on the phthalate were expected to disrupt the stacking of the phenyl groups more or less.  相似文献   

5.
A gas chromatographic–mass spectrometric assay is described for identification and quantification of the antifreezes ethylene glycol (EG) and diethylene glycol (DEG) in plasma for early diagnosis of a glycol intoxication. After addition of 1,3-propanediol as internal standard, the plasma sample was deproteinized by acetone and an aliquot of the supernatant was evaporated followed by microwave-assisted pivalylation. After gas chromatographic separation, the glycols were first identified by comparison of the full mass spectra with reference spectra and then quantified. The quantification has been validated according to the criteria established by the Journal of Chromatography B. The assay was found to be selective. The calibration curves for EG and DEG were linear from 0.1 g/l to 1.0 g/l. The limit of detection for EG and DEG was 0.01 g/l and the limit of quantification for both was 0.1 g/l. The absolute recoveries were 50 and 65% for the low quality control samples and 51 and 73% for the high quality control samples of EG and DEG, respectively. Intra- and inter-day accuracy and precision were inside the required limits. The glycols in frozen plasma samples were stable for more than 6 months. The method was successfully applied to several authentic plasma samples from patients intoxicated with glycols. It has also been suitable for analysis of EG and DEG in urine.  相似文献   

6.
热带观赏水草--红玫瑰的组织培养和快速繁殖   总被引:9,自引:1,他引:9  
1植物名称红玫瑰皇冠(Echinodorus horemanii‘NRUBL'). 2材料类别腋芽(图1). 3培养条件(1)诱导休眠芽萌动培养基:MS 6-BA 2 mg·L-1(单位下同) NAA 0.5;(2)不定芽诱导和继代培养基:MS 6-BA 5 AD(adenine)10;(3)生根培养基:MS 6-BA 0.2 IBA 0.5.上述培养基均附加30 g·L-1蔗糖、4 g·L-1卡拉胶,pH 5.8.培养温度25~26℃,光照度2 000 lx,光照时间10 h·d-1.  相似文献   

7.
This study investigates synthesis of poly(3‐hydroxybutyrate)/diethylene glycol copolymers (P3HB/DEG) by Cupriavidus eutrophus B‐10646 cells as related to DEG concentration in the medium and the time when it is added to the culture of cells synthesizing P3HB. The study determines the limits of physiological effect of DEG on C. eutrophus cells, showing that at DEG concentrations above 30 g/L, it inhibits cell growth, decreasing cell concentration and total P3HB/DEG yield and inducing an increase in the degree of saturation of fatty acids in lipids of cell cytoplasmic membrane. A series of copolymers containing different molar fractions of DEG (between 0.13 and 3.0 mol%) have been synthesized and their physicochemical, physical/mechanical, and biological properties have been investigated as related to the chemical composition and proportions of DEG monomers of the polymers. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1017–1028, 2016  相似文献   

8.
Microbial degradation of jet fuel leads to the accumulation of sludge in fuel distribution systems and storage tanks. To prevent this phenomenon, the biocidal anti-icing inhibitor diethylene glycol monomethyl ether (DiEGME) is routinely added to the fuel. The fate of DiEGME in soil and its consequent effect on the biodegradation of jet fuel by indigenous soil microflora have not been investigated. The aim of this work was to study the kinetics of biodegradation of jet fuel in dark rendzina soil, as affected by the presence of DiEGME. Our data show that the degradability in soil of jet fuel amended with DiEGME was tenfold higher than that of non-amended fuel. Consequently, there was an increase in the jet-fuel-utilizing soil microbial populations during the 100 days of incubation of soil samples amended with jet fuel containing DiEGME. Gas chromatograms of distilled fractions of jet fuel extracted from the soil demonstrated that most of the light fractions' extracts could not be detected at the end of the 100-day incubation. The relative concentration of aromatic compounds in the soil contaminated with DiEGME-amended jet fuel increased during incubation, demonstrating the lower biodegradation rate of these components compared with other fuel components. DiEGME was partially degraded by the general microbial population of the soil. Maximal DiEGME degradation was obtained with specific jet-fuel-utilizing microbial strains – Pseudomonas aeruginosa and Cladosporium resinae – that were added to a carbon-free mineral medium. The degradation rate of DiEGME by specific strains or by soil mixed populations bore an inverse relationship to the DiEGME concentration. The finding that DiEGME can be degraded by indigenous soil microorganisms may have facilitated its utilization also by jet-fuel-degrading microorganisms.  相似文献   

9.
红蛋的组织培养和快速繁殖   总被引:6,自引:0,他引:6  
1 植物名称 红蛋 (Echinodorusosiris)。2 材料类别 茎尖 (budofthestem)。3 培养条件  ( 1 )诱导芽培养基 :1 / 3MS + 6 BA1 .0mg·L- 1 (单位下同 ) +IBA 0 .1 + 3%蔗糖(sugar) ;( 2 )增殖培养基 :MS + 6 BA 1 .0 +IBA0 .0 5 + 3%蔗糖 ;( 3)生根培养基 :1 / 2MS + 6 BA0 .0 5 +IBA 0 .7+ 2 .5 %蔗糖。上述培养基加入 5 .0 g·L- 1 倍力凝 (一种微生物多糖固化剂 ,河北科技大学生产 ) ,pH 5 .8。培养温度为 2 0~ 2 8℃ ,光照度为 1 5 0 0~ 2 0 0 0lx ,光照时间 1 0h·d- 1 。4 生长与分化情况4.1 无菌材料的处理 在超…  相似文献   

10.
The physicochemical factors of medium have been studied for their effect on the physiological indices of growth of Pseudomonas putida BS-2 culture utilizing diethylenglycol as the only source of carbon. Action of the supraoptimal temperature on the growth process of P. putida BS-2 is accompanied by a decrease (more than twice) in economic coefficient of substrate and specific growth rate as compared with their maximal values. Dependences of specific growth rate of P. putida BS-2 in the medium with diethylenglycol on the presence of NaCl in it within the range of its concentrations from 0 to 4% and methanol in the concentration range of 0-20 g/l follow the noncompetitive inhibition equation. When NaCl concentration in the medium is more than 4%, complete separation of constructive and energy metabolism processes is observed.  相似文献   

11.
The aerobic biodegradation of National Aeronautics and Space Administration (NASA) wastewater that contains mixtures of highly concentrated methylhydrazine/hydrazine, citric acid and their reaction product was studied on a laboratory-scale fixed film trickle-bed reactor. The degrading organisms, Achromobacter sp., Rhodococcus B30 and Rhodococcus J10, were immobilized on coarse sand grains used as support-media in the columns. Under continuous flow operation, Rhodococcus sp. degraded the methylhydrazine content of the wastewater from a concentration of 10 to 2.5 mg/mL within 12 days and the hydrazine from 0.8 to 0.1 mg/mL in 7 days. The Achromobacter sp. was equally efficient in degrading the organics present in the wastewater, reducing the concentration of the methylhydrazine from 10 to 5 mg/mL within 12 days and that of the hydrazine from 0.8 to 0.2 mg/mL in 7 days. The pseudo first-order rate constants of 0.137 day-1 and 0.232 day-1 were obtained for the removal of methylhydrazine and hydrazine, respectively, in wastewater in the reactor column. In the batch cultures, rate constants for the degradation were 0.046 and 0.079 day-1 for methylhydrazine and hydrazine respectively. These results demonstrate that the continuous flow bioreactor afford greater degradation efficiencies than those obtained when the wastewater was incubated with the microbes in growth-limited batch experiments. They also show that wastewater containing hydrazine is more amenable to microbial degradation than one that is predominant in methylhydrazine, in spite of the longer lag period observed for hydrazine containing wastewater. The influence of substrate concentration and recycle rate on the degradation efficiency is reported. The major advantages of the trickle-bed reactor over the batch system include very high substrate volumetric rate of turnover, higher rates of degradation and tolerance of the 100% concentrated NASA wastewater. The results of the present laboratory scale study will be of great importance in the design and operation of an industrial immobilized biofilm reactor for the treatment of methylhydrazine and hydrazine contaminated NASA wastewater.  相似文献   

12.
Rhodococcus bacteria are considered to be promising degraders of persistent pollutants and are the basis of biological preparations for contaminated wastewater and soil cleanup. Biotechnological application of this group of bacteria is based on the peculiaraties of their metabolism. This review briefly discusses the following main points: I. Growth of Rhodococcus on various aromatic substrates, II. Chloro/methylcatechol transformation pathways, 3-Chlorocatechol branch of the modified ortho-pathway, 4-Chlorocatechol branch of the modified ortho-pathway, Modified 3-chlorocatechol branch in Rhodococcus opacus 1CP, Meta-cleavage ofchlorocatechols, Modified pathway for methylcatechol degradation, III. Approaches to the enhancement of degradation activity, IV. Rhodococcus-based biopreparations, IV. Prospects.  相似文献   

13.
A field experiment was conducted to understand the potential of vetiver grass (Vetiveria zizanioides) in heavy metal uptake from the soil and wastewater. Four main irrigation treatments including T1 (treated industrial wastewater), T2 (1:1 ratio of municipal:industrial wastewater), T3 (treated municipal wastewater) and T4 (fresh water) were applied. Moreover, the effect of arbuscular mycorrhizal fungus (AMF), Glomus mosseae, on plant growth and heavy metal concentration was evaluated. Three main criteria including bioconcentration factor (BCF), translocation factor (TF) and heavy metal uptake were applied to assess the potential of vetiver grass in accumulation and translocation of heavy metals to aerial parts. The highest concentration of heavy metals was found in plant and soil irrigated with T1 treatment followed by T2, T3 and the lowest concentrations were found in T4 treatment. Irrigation with treated municipal wastewater led to a significant increase in plant biomass and heavy metal uptake compared to other treatments. In T1 treatment (industrial wastewater), vetiver grass caused a significant decrease in Zn, Fe, Cu, Cd and Pb concentrations in soil as compared to no-plant treatment (without planting vetiver grass). Therefore, vetiver grass, irrigated with treated industrial wastewater, is a promising method for the development of urban and industrial green space.  相似文献   

14.
Soil samples were collected from 7 sites in the up-, mid-and down-reach along and nearby the wastewater irrigation channel, western Shenyang of China. The concentrations of selected pollutants (mineral oil, PAHs - polycycle aromatic hydrocarbons and Cd) were determined by UV spectrometer, HPLC and AAS (atomic adsorption spectrometer) spectrometer, respectively. Toxicity effects of soils were evaluated by seedling emergence test with root length of wheat as the end-point and by earthworms test with the mortality rate and inhibition rates of body weight as endpoints. Results showed accumulation of pollutants for most soils with concentration of 200.2 mg.kg?1~1600 mg.kg?1 for mineral oil, 0.33 mg.kg?1~1.81 mg.kg?1 for Cd and 900.16 mg.kg?1 ~ 2737.91 mg.kg?1 for PAHs. The inhibition rates of root elongation were from ?20% up to 40 %, and mortality rates of earthworms ranged from 0%~40% from the exposure period of two weeks to eight weeks by sampling interval of two weeks, the inhibition rates of earthworm growth were from ?19.36% to 34.53%, showing effects of stimulation at 2 weeks to an increasing effects of inhibition at 4, 6 and 8 weeks, respectively. Mortality rates correlated with the loss of body weight of earthworms.This study indicated the potential risk of pollutants of environmental low content in soil by the determination of selected chemicals combined with toxicity indexes.  相似文献   

15.
Phylogenetics of Echinodorus (Alismataceae) based on morphological data   总被引:1,自引:1,他引:0  
Echinodorus (Alismataceae) is a genus of aquatic and semi-aquatic herbs naturally distributed from Argentina to the USA but commonly used as ornamentals in aquaria worldwide. The phylogeny of the genus was studied on the basis of 96 morphological characters. The analysis resulted in a single most-parsimonious tree supporting a polyphyletic origin of the genus. However, subgenus Echinodorus together with Echinodorus nymphaeifolius formed a clade. Two large clades can be recognized in Echinodorus s.s. , but previous subdivisions of the genus are not supported and some earlier proposed subspecific combinations were shown to be non-monophyletic. Addition of continuous characters coded as value ranges enhanced both the resolution and the support values of the tree. Hence, inclusion of continuous overlapping data is encouraged in phylogenetic studies.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 291–305.  相似文献   

16.
Soil samples were collected from 7 sites in the up-, mid- and down-reach along and nearby the wastewater irrigation channel, western Shenyang of China. The concentrations of selected pollutants (mineral oil, PAHs - polycycle aromatic hydrocarbons and Cd) were determined by UV spectrometer, HPLC and AAS (atomic adsorption spectrometer) spectrometer, respectively. Toxicity effects of soils were evaluated by seedling emergence test with root length of wheat as the end-point and by earthworms test with the mortality rate and inhibition rates of body weight as endpoints. Results showed accumulation of pollutants for most soils with concentration of 200.2 mg·kg-1-1600 mg·kg-1 for mineral oil, 0.33 mg·kg-1-1.81 mg·kg-1 for Cd and 900.16 mg·kg-1 -2737.91 mg·kg-1 for PAHs. The inhibition rates of root elongation were from -20% up to 40 %, and mortality rates of earthworms ranged from 0%-40% from the exposure period of two weeks to eight weeks by sampling interval of two weeks, the inhibition rates of earthw  相似文献   

17.

Soil samples were collected from 7 sites in the up-, mid-and down-reach along and nearby the wastewater irrigation channel, western Shenyang of China. The concentrations of selected pollutants (mineral oil, PAHs - polycycle aromatic hydrocarbons and Cd) were determined by UV spectrometer, HPLC and AAS (atomic adsorption spectrometer) spectrometer, respectively. Toxicity effects of soils were evaluated by seedling emergence test with root length of wheat as the end-point and by earthworms test with the mortality rate and inhibition rates of body weight as endpoints. Results showed accumulation of pollutants for most soils with concentration of 200.2 mg.kg−1∼1600 mg.kg−1 for mineral oil, 0.33 mg.kg−1∼1.81 mg.kg−1 for Cd and 900.16 mg.kg−1 ∼ 2737.91 mg.kg−1 for PAHs. The inhibition rates of root elongation were from −20% up to 40 %, and mortality rates of earthworms ranged from 0%∼40% from the exposure period of two weeks to eight weeks by sampling interval of two weeks, the inhibition rates of earthworm growth were from −19.36% to 34.53%, showing effects of stimulation at 2 weeks to an increasing effects of inhibition at 4, 6 and 8 weeks, respectively. Mortality rates correlated with the loss of body weight of earthworms.

This study indicated the potential risk of pollutants of environmental low content in soil by the determination of selected chemicals combined with toxicity indexes.

  相似文献   

18.
Soil samples were collected from 7 sites in the up-, mid- and down-reach along and nearby the wastewater irrigation channel, western Shenyang of China. The concentrations of selected pollutants (mineral oil, PAHs - polycycle aromatic hydrocarbons and Cd) were determined by UV spectrometer, HPLC and AAS (atomic adsorption spectrometer) spectrometer, respectively. Toxicity effects of soils were evaluated by seedling emergence test with root length of wheat as the end-point and by earthworms test with the mortality rate and inhibition rates of body weight as endpoints. Results showed accumulation of pollutants for most soils with concentration of 200.2 mg.kg-1 ~1600 mg.kg-1 for mineral oil, 0.33 mg.kg-1~1.81 mg.kg-1 for Cd and 900.16 mg.kg-1~ 2737.91 mg.kg-1 for PAHs. The inhibition rates of root elongation were from -20% up to 40 %, and mortality rates of earthworms ranged from 0%~40% from the exposure period of two weeks to eight weeks by sampling interval of two weeks, the inhibition rates of earthworm growth were from -19.36% to 34.53%, showing effects of stimulation at 2 weeks to an increasing effects of inhibition at 4, 6 and 8 weeks, respectively. Mortality rates correlated with the loss of body weight of earthworms.This study indicated the potential risk of pollutants of environmental low content in soil by the determination of selected chemicals combined with toxicity indexes.  相似文献   

19.
Production of biosurfactant from an alkaliphilic bacterium Cronobacter sakazakii (accession no. JN398668) was screened by haemolytic assay, emulsifying activity and surface tension measurement. Biosurfactant, comprised of total sugars (73.3%), reducing sugars (1.464%), protein (11.9%), uronic acid (15.98%) and sulfate (6.015%), showed low viscosity with pseudoplastic rheological behavior and exhibited significant emulsification activity with oils and hydrocarbons. A series of low and mid range mass peaks (m/z) corresponding to mono-, di-, tri- and oligosaccharides were detected in the positive ion reflector mode of MALDI TOF-TOF MS. GC-MS analysis revealed composition of monosaccharide moieties (w/w) viz. glucose (14%), mannose (24%), galactose (14%), xylose (20%) and arabinose (1.9%). 1H NMR, FT-IR and EDX analyses confirmed the characteristic various functional groups, bonds and elements respectively. Thermostability (up to 260 °C) and CI (0.456) were determined by TG and DSC analyses. Inherent properties of biosurfactant make it a potential candidate for bioremediation of oil and hydrocarbons.  相似文献   

20.
In this work the performance of a Membrane bioreactor (MBR) was assessed for the removal of 3-15 mg/l of copper, lead, nickel and zinc from wastewater. The average removal efficiencies accomplished by the MBR system were 80% for Cu(II), 98% for Pb(II), 50% for Ni(II) and 77% for Zn(II). The addition of 5 g/l vermiculite into the biological reactor enhanced metal removal to 88% for copper, 85% for zinc and 60% for nickel due to adsorption of metal ions on the mineral, while it reduced biomass inhibition and increased biomass growth. The metal ions remaining in soluble form penetrated into the permeate, while those attached to sludge flocs were effectively retained by the ultrafiltration membranes. The average heterotrophic biomass inhibition was 50%, while it reduced to 29% when lower metal concentrations were fed into the reactor in the presence of vermiculite. The respective autotrophic biomass inhibition was 70% and 36%. The presence of heavy metals and vermiculite in the mixed liquor adversely impacted on membrane fouling.  相似文献   

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