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1.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(10): 975-979, 2019 Oct 10.
Artigo em Chinês | MEDLINE | ID: mdl-31598939

RESUMO

OBJECTIVE: To assess the effect of miR-137 on the proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs) induced by high glucose and its mechanism. METHODS: HUVECs cells were divided into low-glucose group (5.5 mmol/L glucose-treated cells), high-glucose group (33.36 mmol/L glucose-treated cells), anti-NC group (cells treated with 33.36 mmol/L glucose after anti-NC transfection) and anti-miR-137 group (cells treated with 33.36 mmol/L glucose after anti-miR-137 transfection). After 48 hours, qRT-PCR was used to determine the expression of miR-137. CCK-8 assay and flow cytometry were used to detect cell proliferation and apoptosis rate, respectively. The targeting relationship between miR-137 and AKT2 was validated by dual fluorescence reporter gene detection system and AKT2 protein expression after overexpression or inhibition of miR-137. RESULTS: High glucose could significantly up-regulate the expression of miR-137 in HUVECs cells, and the expression of miR-137 in HUVECs cells transfected with miR-137 inhibitor was significantly decreased (P<0.05). High glucose can significantly inhibit HUVECs cell proliferation and induce apoptosis, while inhibition of miR-137 expression can weaken the effect of high glucose on HUVECs cell proliferation inhibition and apoptosis promotion (P<0.05). Inhibiting AKT2 expression could weaken the inhibitory effect of miR-137 inhibitor on HUVECs cell proliferation and apoptosis (P<0.05). CONCLUSION: Inhibiting the expression of miR-137 gene can attenuate the proliferation inhibition and apoptosis promotion of HUVECs induced by high glucose, and the mechanism is related to activating the expression of AKT2.


Assuntos
Apoptose , Proliferação de Células , Células Endoteliais da Veia Umbilical Humana/citologia , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-akt/genética , Células Cultivadas , Glucose , Humanos
2.
Small ; 15(42): e1902420, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31469502

RESUMO

Potassium manganese hexacyanoferrate (KMHCF) is a low-cost Prussian blue analogue (PBA) having a rigid and open framework that can accommodate large alkali ions. Herein, the synthesis of KMHCF and its application as a high-performance cathode in sodium-ion batteries (NIBs) is reported. High-quality KMHCF with low amounts of crystal water and defects and with homogeneous microstructure is obtained by controlling the nucleation and grain growth by using a high-concentration citrate solution as a precipitation medium. The obtained KMHCF exhibits superior cycling and rate performance as a NIB cathode, showing 80% capacity retention after 1000 cycles at 1 C and a high capacity of 95 mA h g-1 at 20 C. Unlike conventional single-cation batteries, the hybrid NIB with KMHCF as cathode and Na as anode in Na-ion electrolyte displays three reversible plateaus that involve stepwise insertion/extraction of both K+ and Na+ in the PBA framework. In later cycling, the K+ -Na+ cointercalated phase is partially converted into a cubic sodium manganese hexacyanoferrate (NaMHCF) phase due to the increasing replacement of Na+ for K+ .

3.
ACS Appl Mater Interfaces ; 11(21): 19647-19653, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31055915

RESUMO

Antimony (Sb) heavily-doped germanium (Ge)-on-silicon (Si) epitaxial films are investigated as mid-infrared (MIR) plasmonic materials. Structural, electrical, and optical properties have been improved by proper choice of dopant species (i.e., Sb) and optimization of the growth parameters (i.e., Sb flux and substrate temperature). The increased electron conductivity can be attributed to the elevated carrier concentration (1.5 × 1020 cm-3) and carrier mobility (224 cm2 V-1 s-1) in the Sb-doped Ge epilayers. The measured MIR reflectivities of the Sb-doped Ge films show free-carrier-dependent properties, which leads to tunable real and imaginary parts of permittivities. Localized surface plasmon polaritons of the bowtie antennas fabricated from the Sb-doped Ge films are demonstrated. The fabricated antennas can provide signal enhancement for the molecular vibrational spectroscopy when these vibrational lines are spectrally in proximity to the localized plasmon resonance. These CMOS-compatible Sb-doped Ge epilayers offer a platform to study the interaction of MIR plasmon with nanostructures on chips.

4.
Environ Sci Pollut Res Int ; 25(23): 22736-22743, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29855873

RESUMO

In this study, the microbial degradation of alpha-cypermethrin was investigated in 14 different soil samples by compound-specific stable isotope analysis. After 40 and 80 days of microbial degradation, the stable carbon isotope ratios of alpha-cypermethrin shifted from - 32.18 to - 31.87‰ ~ - 31.12 and - 31.45‰ ~ - 29.75‰ in the soils, respectively. The microbial degradation percentages of alpha-cypermethrin were calculated as 15.6~44.3% after 40 days of incubation and 33.3~73.9% after 80 days of incubation. The effects of physicochemical properties of soil samples were then explored on the microbial degradation of alpha-cypermethrin. The results revealed that the microbial degradation percentages were positively correlated with the contents of organic carbon in soils with Pearson correlation coefficients of 0.794 and 0.843 for 40 and 80 days of microbial degradation, respectively, indicating that the microbial degradation of alpha-cypermethrin was faster in the soil with higher content of organic carbon. Accordingly, soil-specific use should be considered in practical agricultural application of alpha-cypermethrin to reduce the residue of the pesticide.

5.
ACS Appl Mater Interfaces ; 10(17): 14886-14893, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29644842

RESUMO

Indium tin oxide (ITO)-based sandwich structures with the insertion of ultrathin (<10 nm) titanium nitride (TiN) are investigated as near-infrared (NIR) plasmonic materials. The structural, electrical, and optical properties reveal the improvement of the sandwich structures stemmed from TiN insertion. TiN is a well-established alternative to noble metals such as gold, elevating the electron conductivity of sandwich structures as its thickness increases. Dielectric permittivities of TiN and top ITO layers show TiN-thickness-dependent properties, which lead to moderate and tunable effective permittivities for the sandwiches. The surface plasmon polaritons (SPP) of the ITO-TiN-ITO sandwich at the telecommunication window (1480-1570 nm) are activated by prism coupling using Kretschmann configuration. Compared with pure ITO films or sandwiches with metal insertion, the reflectivity dip for sandwiches with TiN is relatively deeper and wider, indicating the enhanced coupling ability in plasmonic materials for telecommunications. The SPP spatial profile, penetration depth, and degree of confinement, as well as the quality factors, demonstrate the applicability of such sandwiches for NIR plasmonic materials in various devices.

6.
J Hazard Mater ; 349: 1-9, 2018 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-29414739

RESUMO

In this study, the microbial degradation of six pyrethroids (bifenthrin, fenpropathrin, permethrin, α-cypermethrin, fenvalerate and deltamethrin) was investigated in soil to develop a new approach to estimate bioavailability of pyrethoids by compound-specific stable isotope analysis (CSIA). After 56-day incubation, the residual concentrations of pyrethroids in unsterilized soil were much lower than those in sterilized soil, indicating that microbial degradation was dominant for the elimination of pyrethroids. Meanwhile, the stable carbon isotope ratios of the six pyrethroids were determined during the degradation. Significant stable carbon isotope fractionation was observed during the microbial degradation of fenpropathrin, α-cypermethrin and deltamethrinhe. The enrichment factor ε was determined as -1.88‰, -1.82‰ and -2.00‰, respectively. A new approach was then developed to estimate the bioavailability of the three pyrethroids by determining stable carbon isotope ratios. The approach established in the study provides an alternative method to dynamically and quantitatively estimate bioavailability of compounds in soil based on CSIA.

7.
Can J Infect Dis Med Microbiol ; 2016: 3879635, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27379169

RESUMO

A 63-year-old-man was admitted to our hospital with severe subungual abscess. Bacteria were isolated from pus samples, and an inconsistent identification was shown by VITEK 2 system and MALDI-TOF mass spectrometry as Raoultella planticola and Raoultella terrigena, respectively. Molecular identification by 16S rRNA sequencing suggested that the isolate is R. terrigena, and this was further demonstrated by sequencing three housekeeping genes (rpoB, gyrA, and parC) with phylogenetic analysis. To our knowledge, this is the first report of subungual abscess caused by R. terrigena, a rare case of human infection due to soil bacterium. Our study highlights the technique importance on this pathogen identification.

8.
Sci Total Environ ; 554-555: 211-7, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26950635

RESUMO

Organophosphate esters (OPEs) have been widely used in various products as alternatives to brominated flame retardants. Although widespread OPE exposure is expected in humans, the accumulation of OPEs has seldom been studied in the human body. In this study, 12 OPE analogs were analyzed in 50 human placentas collected in Eastern China. The concentrations of the 9 most frequently detected OPEs (Σ9OPEs) ranged from 34.4 to 862ng/g lipid weight (lw), with a median of 301ng/g lw. Tri(2-chloroethyl) phosphate (TCEP) was identified as the most abundant analog, with a median concentration of 142ng/g lw, followed by tributoxyethyl phosphate (TBEP) and triphenyl phosphate (TPhP). Statistical analysis showed no analog of OPEs or Σ9OPEs was positively correlated with the lipid content of the placentas. There were no correlations observed between the OPE concentrations and maternal characteristics. Food consumption habits exhibited weak effects on OPE levels in the placentas. Further investigation is required to determine the effects of OPEs on fetuses due to the expected increase in maternal exposure to these esters.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Retardadores de Chama/metabolismo , Exposição Materna/estatística & dados numéricos , Organofosfatos/metabolismo , Placenta/metabolismo , Plastificantes/metabolismo , China , Feminino , Humanos , Gravidez
9.
Extremophiles ; 20(1): 37-44, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26560315

RESUMO

In this study, a novel metallo-ß-lactamases fold hydrolase PH-1 was identified from Pelagibacterium halotolerans B2(T). This novel member of the family Hyphomicrobiaceae was isolated from the East China Sea. In silico analysis demonstrated that PH-1 and its relative homologues cluster in a unique branch and constitute a new subgroup among MBLs. PH-1 was cloned and overexpressed in Escherichia coli BL21 in a soluble form. SDS-PAGE, MALDI-TOF/TOF-MS, and size-exclusion chromatography analysis demonstrated that the PH-1 was a monomer with molecular weight of about 29 kDa. Substrate specificity study showed PH-1 preferred penicillin type ß-lactams and exhibited maximum activity toward penicillin-G. Additionally, our experiments also revealed that PH-1 was a halotolerant enzyme since it is active under 4 M NaCl. The enzyme activity of PH-1 was negatively affected by 1 mM Mn(2+) and EDTA. These observations lay a foundation for further study of MBLs from marine bacterium.


Assuntos
Proteínas de Bactérias/metabolismo , Hyphomicrobiaceae/enzimologia , beta-Lactamases/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Hyphomicrobiaceae/genética , Hyphomicrobiaceae/isolamento & purificação , Lactamas/metabolismo , Dados de Sequência Molecular , Especificidade por Substrato , beta-Lactamases/química , beta-Lactamases/genética
10.
J Biotechnol ; 216: 65-6, 2015 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-26432337

RESUMO

Lactobacillus heilongjiangensis DSM 28069(T) is a potential probiotic isolated from traditional Chinese pickle. Here we report the complete genome sequence of this strain. The complete genome is 2,790,548bp with the GC content of 37.5% and devoid of plasmids. Sets of genes involved in the biosynthesis of riboflavin and folate were identified in the genome, which revealed its potential application in biotechnological industry. The genome sequence of L. heilongjiangensis DSM 28069(T) now provides the fundamental information for future studies.


Assuntos
Genoma Bacteriano , Lactobacillus/genética , Probióticos/farmacologia , Sequência de Bases
11.
Sci Total Environ ; 532: 415-9, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26092290

RESUMO

In this study, the microbial degradation of lambda-cyhalothrin in soil was investigated using compound-specific stable isotope analysis. The results revealed that lambda-cyhalothrin was biodegraded in soil under laboratory conditions. The half-lives of lambda-cyhalothrin were determined to be 49 and 161 days in non-sterile and sterile soils spiked with 2mg/kg lambda-cyhalothrin and 84 and 154 days in non-sterile and sterile soils spiked with 10mg/kg lambda-cyhalothrin, respectively. The biodegradation of lambda-cyhalothrin resulted in carbon isotope fractionation, which shifted from -29.0‰ to -26.5‰ in soil spiked with 2mg/kg lambda-cyhalothrin, and to -27.5‰ with 10mg/kg lambda-cyhalothrin. A relationship was established between the stable carbon isotope fraction and the residual concentrations of lambda-cyhalothrin by the Rayleigh equation in which the carbon isotope enrichment factor ε of the microbial degradation of lambda-cyhalothrin in the soil was calculated as -2.53‰. This study provides an approach to quantitatively evaluate the biodegradation of lambda-cyhalothrin in soil in field studies.


Assuntos
Nitrilos/metabolismo , Piretrinas/metabolismo , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Isótopos de Carbono , Fracionamento Químico , Nitrilos/análise , Piretrinas/análise , Poluentes Químicos da Água/análise
12.
J Hazard Mater ; 295: 37-42, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25880047

RESUMO

To assess microbial degradation of alpha-cypermethrin in soil, attenuation of alpha-cypermethrin was investigated by compound-specific stable isotope analysis. The variations of the residual concentrations and stable carbon isotope ratios of alpha-cypermethrin were detected in unsterilized and sterilized soils spiked with alpha-cypermethrin. After an 80 days' incubation, the concentrations of alpha-cypermethrin decreased to 0.47 and 3.41 mg/kg in the unsterilized soils spiked with 2 and 10 mg/kg, while those decreased to 1.43 and 6.61 mg/kg in the sterilized soils. Meanwhile, the carbon isotope ratios shifted to -29.14 ± 0.22‰ and -29.86 ± 0.33‰ in the unsterilized soils spiked with 2 and 10 mg/kg, respectively. The results revealed that microbial degradation contributed to the attenuation of alpha-cypermethrin and induced the carbon isotope fractionation. In order to quantitatively assess microbial degradation, a relationship between carbon isotope ratios and residual concentrations of alpha-cypermethrin was established according to Rayleigh equation. An enrichment factor, ϵ = -1.87‰ was obtained, which can be employed to assess microbial degradation of alpha-cypermethrin. The significant carbon isotope fractionation during microbial degradation suggests that CSIA is a proper approach to qualitatively detect and quantitatively assess the biodegradation during attenuation process of alpha-cypermethrin in the field.


Assuntos
Piretrinas/metabolismo , Biodegradação Ambiental , Isótopos de Carbono/análise , Piretrinas/análise , Solo/química
13.
Braz. j. infect. dis ; 19(1): 85-89, Jan-Feb/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-741235

RESUMO

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) are increasingly causing infective endocarditis over the past decade. Here we report a healthy man who developed a severe acute infective endocarditis with systemic embolism caused by CA- MRSA. The strain was recovered from repeated blood cultures and was characterized using molecular detection and genotyping. The S. aureus isolate was typed as ST630 SCCmecV with spa-type t4549, agrI/IV and was PVL-negative. This is the only case report, to our knowledge, of CA-MRSA infective endocarditis in China. This case highlights the emergence and geographical spread of life-threatening CA-MRSA infection within China.


Assuntos
Adulto , Humanos , Masculino , Embolia Paradoxal/etiologia , Endocardite Bacteriana/microbiologia , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas/microbiologia , Infecções Comunitárias Adquiridas , Endocardite Bacteriana/complicações , Índice de Gravidade de Doença , Infecções Estafilocócicas/complicações
14.
Braz J Infect Dis ; 19(1): 85-9, 2015 Jan-Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25193080

RESUMO

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) are increasingly causing infective endocarditis over the past decade. Here we report a healthy man who developed a severe acute infective endocarditis with systemic embolism caused by CA-MRSA. The strain was recovered from repeated blood cultures and was characterized using molecular detection and genotyping. The S. aureus isolate was typed as ST630 SCCmecV with spa-type t4549, agrI/IV and was PVL-negative. This is the only case report, to our knowledge, of CA-MRSA infective endocarditis in China. This case highlights the emergence and geographical spread of life-threatening CA-MRSA infection within China.


Assuntos
Embolia Paradoxal/etiologia , Endocardite Bacteriana/microbiologia , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas/microbiologia , Adulto , Infecções Comunitárias Adquiridas , Endocardite Bacteriana/complicações , Humanos , Masculino , Índice de Gravidade de Doença , Infecções Estafilocócicas/complicações
15.
Ying Yong Sheng Tai Xue Bao ; 24(10): 2888-96, 2013 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-24483084

RESUMO

The landslide on vegetated slopes caused by extreme weather has being increased steadily, and the preferential flow in soil macropores plays an important role in the landslide. By using water breakthrough curve and Poiseuille equation, this paper estimated the radius range, amount, and average volume of soil macropores on a vegetated basalt slope of Maka Mountain, Southwest China, and analyzed the distribution of the soil macropores and the main affecting factors. In the study area, the radius of soil macropores ranged from 0.3 to 1.8 mm, mainly between 0.5 and 1.2 mm. The large-radius macropores (1.4-1.8 mm) were lesser, while the small-radius macropores (< 1.4 mm) were more. With the development of soil profile, soil macropores were more in upper layers and lesser in deeper layers. The average volume of the macropores contributed 84.7% to the variance of steady effluent rate. Among the factors affecting the average volume of the large macropores, vegetations root mass had a linear relationship, with the correlation coefficient being 0.70, and soil organic matter content also had a linear relationship, with the correlation coefficient being 0.64.


Assuntos
Conservação dos Recursos Naturais/métodos , Solo/química , Árvores/crescimento & desenvolvimento , Movimentos da Água , China , Ecossistema , Poaceae/crescimento & desenvolvimento , Porosidade , Chuva
16.
Neural Regen Res ; 8(27): 2510-9, 2013 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-25206561

RESUMO

In this study, we aimed to explore the role of ursolic acid in the neural regeneration of the injured sciatic nerve. BALB/c mice were used to establish models of sciatic nerve injury through unilateral sciatic nerve complete transection and microscopic anastomosis at 0.5 cm below the ischial tube-rosity. The successfully generated model mice were treated with 10, 5, or 2.5 mg/kg ursolic acid via intraperitoneal injection. Enzyme-linked immunosorbent assay results showed that serum S100 protein expression level gradually increased at 1-4 weeks after sciatic nerve injury, and significantly decreased at 8 weeks. As such, ursolic acid has the capacity to significantly increase S100 protein expression levels. Real-time quantitative PCR showed that S100 mRNA expression in the L4-6 segments on the injury side was increased after ursolic acid treatment. In addition, the muscular mass index in the soleus muscle was also increased in mice treated with ursolic acid. Toluidine blue staining revealed that the quantity and average diameter of myelinated nerve fibers in the injured sciatic nerve were significantly increased after treatment with ursolic acid. 10 and 5 mg/kg of ursolic acid produced stronger effects than 2.5 mg/kg of ursolic acid. Our findings indicate that ursolic acid can dose-dependently increase S100 expression and promote neural regeneration in BALB/c mice following sciatic nerve injury.

17.
Ying Yong Sheng Tai Xue Bao ; 23(4): 1137-44, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-22803486

RESUMO

Desiccation cracking of soil body is a complex physical process, which can affect the strength, stability, and permeability of soil body, and involve in several disciplines such as soil science, agricultural science, engineering geology, and environmental science. This paper introduced the significances of the study on the desiccation cracking of soil body, reviewed the related theoretical and applied researches and the quantitative analysis of crack morphology, and discussed the deficiencies in the research fields, research contents, and research methods. The future research directions about the desiccation cracking of soil body were pointed out.


Assuntos
Conservação dos Recursos Naturais/métodos , Dessecação , Ecossistema , Monitoramento Ambiental/métodos , Solo/química
18.
Talanta ; 85(1): 56-62, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21645669

RESUMO

Highly ordered titanium dioxide (TiO(2)) nanotubes film was successfully synthesized via anodic oxidation of a Ti foil in an ammonium fluoride-based ethylene glycol solution. The electrogenerated chemiluminescence (ECL) behavior of the resulting TiO(2) nanotubes film was subsequently studied. Strong ECL emission was observed at -1.40V (vs. Ag/AgCl) and the ECL spectrum displayed three emission peaks which were bathochromatically shifted by ca. 140nm as compared to its corresponding photoluminescence (PL) emission peaks, indicating that the surface state plays an important role in the emission process. The ECL emission can also occur in a deareated solution attributing to the surface adsorbed O(2) molecules. The ECL emission intensity was quenched by dopamine and greatly enhanced in the presence of dissolved O(2) and H(2)O(2), making it possible to detect these analytes. The TiO(2) nanotubes film has been successfully applied to determine the dissolved O(2) content in river and pond water samples, the H(2)O(2) concentration in commercial disinfectant samples and the dopamine concentration in commercial dopamine injections with satisfactory results. The plausible ECL mechanisms of TiO(2) nanotubes film in aqueous solution are discussed.


Assuntos
Dopamina/análise , Técnicas Eletroquímicas/métodos , Peróxido de Hidrogênio/análise , Luminescência , Nanotubos/química , Oxigênio/análise , Titânio/química , Água Doce/química , Rios/química
19.
J Exp Biol ; 213(Pt 9): 1591-601, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20400645

RESUMO

The saccule is known to play an important role in hearing in fishes. In this study we investigated spatial frequency selectivity of single saccular afferents in a teleost fish (the sleeper goby, Dormitator latifrons) to acoustic particle motion at 50-400 Hz. Saccular afferents have similar distributions of best sensitivity (-90.0 to -54.8 dB re. 1 g, mean +/- s.d.=-81.1+/-8.0 dB) and characteristic frequencies (

Assuntos
Perciformes/fisiologia , Estimulação Acústica , Animais , Audição , Neurônios Aferentes/metabolismo , Sáculo e Utrículo/metabolismo
20.
J Chromatogr A ; 1216(15): 3343-8, 2009 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-19268954

RESUMO

A method for preparation of a stationary phase-adjustable column with in-column stationary phase-coated fused-silica fiber annular column was successfully developed. The surface of a 0.12 mm o.d. bare optical fiber was first coated with a stationary phase and then inserted into a fused-silica capillary (non-coated or coated) as an annular column for gas chromatographic study. The optical fiber and capillary were coated with polydimethylsiloxane (SE-30) and polyethylene glycol 20 M (PEG-20 M) as nonpolar and polar stationary phases, respectively. Among the investigated annular and open tubular columns, the PEG-20 M-coated fiber-in-PEG-20 M-coated capillary annular column showed the highest column efficiency with a minimum plate height of 0.35 mm and an optimum gas velocity of 25 cm/s. When a SE-30/PEG-20 M-coated fiber-in-uncoated capillary annular column was applied to separate a 9-component complex mixture, the total analysis time was 5.3 min and the column length was 12 m. By contrast, when a SE-30-coated fiber-in-PEG-20 M-coated capillary annular column was used to separate the same 9-component mixture, the analysis time was reduced to 3.5 min and the column length was shortened by half to 6m. Our results show that the stationary phase-coated fiber-in-stationary phase-coated capillary annular column is a better choice for gas chromatographic separation as it is more efficient and flexible. In addition, the proposed annular column design provides flexibility in using two or even more types of stationary phases to achieve optimal analytical separation.


Assuntos
Cromatografia Gasosa/instrumentação , Alcanos/isolamento & purificação , Dimetilpolisiloxanos/química , Desenho de Equipamento , Hidrocarbonetos Aromáticos/isolamento & purificação , Polietilenoglicóis/química
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