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A simple, rapid, and sensitive high-performance thin-layer chromatographic method has been developed and validated for analysis of residues of imidacloprid, fenitrothion, and parathion in Chinese cabbage. The sample was extracted by sonication in an ultrasonic water bath with acetone-petroleum ether, 5:3 ( v / v ), and the extract was directly applied, as bands, to glass-backed silica gel 60F 254 HPTLC plates. The plates were developed with hexane-acetone, 7 + 3 ( v / v ), in an unsaturated glass twin-trough Camag chamber. Evaluation of the developed HPTLC plates was performed densitometrically with a Camag TLC Scanner 3 controlled by an external PC running Wincats software (Version 1.1.2). The results indicated that the detection limits of imidacloprid ( R F = 0.10), fenitrothion ( R F = 0.59), and parathion ( R F = 0.70) were 5.0 × 10 −9 g, 2.0 × 10 −8 g, 1.0 × 10 −8 g, respectively. Recoveries of the pesticides from Chinese cabbage by use of this analytical method were 80.04–85.22%, and RSD were 4.18–13.15%. The precision and accuracy of the method were generally fit for analysis of pesticide residues in Chinese cabbage.

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Abstract  

The catalytic properties of a novel MFI-type zeolite with different SiO2/Al2O3 ratio in the dehydration of glucose to levulinic acid (LA) were investigated in this work. The results demonstrate the strength of acidic sites and the mesoporosity of the zeolites have significant effects on LA formation.

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Abstract  

In this work, elemental distributions in the rat olfactory bulbs (OB) were measured by synchrotron radiation X-ray fluorescence (SRXRF) 9 hours after unilateral intranaris application of MnCl2 solution. The effects of deposition of exogenous Mn in the OB on the distributions of other elements, particularly calcium, were also investigated. The results show that the application of MnCl2 solution in the nasal cavity resulted in inhomogeneous deposition of Mn in the OB, with the highest Mn content found in the ipsilateral glomerular layer (GL). Locations in the ipsilateral hemisphere of the OB with higher Mn content were found to be associated with significantly higher calcium and zinc contents, suggesting the presence of excess exogenous Mn may affect the homeostasis of other trace elements such as calcium and zinc.

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Abstract  

Fenton’s reagent was employed to synthesize glyoxalic acid from glyoxal. The reaction conditions were optimized in a semi-batch reactor. The mechanism and kinetics of the reaction were proposed.

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Abstract  

New and efficient Keggin heteropolyacid (HPA) catalysts were explored for β-pinene (PI) cationic polymerization. Among them, 12-phosphotungstic acid (PW12) dehydrated at 200 °C exhibited high catalytic activity. The overall PI conversion was up to 96.53%, and the obtained polymer product yield was 60.85%. In order to study this new catalyzed reaction, special techniques of FT-IR, 1H-NMR, XRD, and XPS were used in this paper, and it was shown that the crystal structure of the heteropoly anion was not destroyed during the reaction. The protons dissociating from the catalyst played an important role in the polymerization and the HPAs had two important functions: polymerization initiator, and the counter-anion of the growing cation center.

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The immunogenicity of a DNA vaccine expressing the surface protein NcSRS2 of Neospora caninum was studied in BALB/c mice. The NcSRS2-encoding DNA was obtained by PCR amplification of the NcSRS2 ORF gene from the p43 plasmid encoding the N. caninum surface protein NcSRS2, ligated to the mammalian expression vector pcDNA3.1/Zeo(+) and propagated in E. coli DH5α to produce the N. caninum NcSRS2 DNA vaccine. BALB/c mice were immunised by two intramuscular injections of the DNA vaccine with or without complete Freund’s adjuvant (CFA). Serum antibody titres and nitric oxide (NO) concentrations, and splenocyte proliferation and cytokine expression were measured after immunisation. The DNA vaccine induced T-cell-mediated immunity as shown by significantly increased NO concentrations, cytokine gene (IL-2 and IFN-γ) expression, and NcSRS2 protein-stimulated lymphocyte proliferation in mice immunised with the DNA vaccine. The vaccine also induced weak humoral immunity. The immunogenicity of the DNA vaccine was slightly enhanced by CFA. The immune response was specific to NcSRS2. No immune response was observed in mice immunised with the pcDNA3.1/Zeo(+) vector alone.

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Abstract

Asymmetric electro-epoxidation of olefins had been achieved with sodium hypochlorite (NaClO) as an oxidant, which was generated by electrolysis in two-phase systems of aqueous sodium chloride (NaCl) and ionic liquids (1-butyl-3-methylimidazolium hexafluorophosphate (BMImPF6) and 1-butyl-3-methylimidazolium tetrafluoroborate (BMImBF4)). The electrolysis conditions by different current densities (0.8, 0.9, 1.0, 1.1 and 1.3 mA/cm2) and pH values (8, 9, 10, 11, 12 and 13) were optimized and 1.1 mA/cm2 and pH 11 were selected. The proposed reaction mechanism is also discussed. The performance of new catalytic systems in four kinds of reaction media in the presence or absence of ammonium acetate (NH4OAc) as a cocatalyst was investigated systematically. Compared to the chemical epoxidation systems, the enantiomeric excess (ee) values and yields for the epoxidation of styrene, α-methylstyrene and indene were acceptable in the electrocatalytic epoxidation systems.

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Background and aims

Mindfulness-based intervention (MBI) has been applied in behavioral addiction studies in recent years. However, few empirical studies using MBI have been conducted for smartphone addiction, which is prevalent among Chinese university students. The aim of this study was to investigate the effectiveness of a group mindfulness-based cognitive-behavioral intervention (GMCI) on smartphone addiction in a sample of Chinese university students.

Methods

Students with smartphone addiction were divided into a control group (n = 29) and an intervention group (n = 41). The students in the intervention group received an 8-week GMCI. Smartphone addiction was evaluated using scores from the Mobile Phone Internet Addiction Scale (MPIAS) and self-reported smartphone use time, which were measured at the baseline (1st week, T1), post-intervention (8th week, T2), the first follow-up (14th week, T3), and the second follow-up (20th week, T4).

Results

Twenty-seven students in each group completed the intervention and the follow-up. Smartphone use time and MPIAS scores significantly decreased from T1 to T3 in the intervention group. Compared with the control group, the intervention group had significantly less smartphone use time at T2, T3, and T4 and significantly lower MPIAS scores at T3.

Discussion and conclusion

This pilot study demonstrated that the GMCI could significantly alleviate smartphone addiction among university students.

Open access
Acta Biologica Hungarica
Authors: Xiaoyan Liu, Md. Asaduzzaman Khan, Jingliang Cheng, Chunli Wei, Lianmei Zhang, and Junjiang Fu

Generation of the stable cell lines is a highly efficient tool in functional studies of certain genes or proteins, where the particular genes or proteins are inducibly expressed. The KRAB-associated protein-1 (KAP1) is an important transcription regulatory protein, which is investigated in several molecular biological studies. In this study, we have aimed to generate a stable cell line for inducing KAP1 expression. The recombinant plasmid pcDNA5/FRT/TO-KAP1 was constructed at first, which was then transfected into Flp-In™T-REx™-HEK293 cells to establish an inducible pcDNA5/FRT/TO-KAP1-HEK293 cell line. The Western blot analysis showed that the protein level of KAP1 is over-expressed in the established stable cell line by doxycycline induction, both dose and time dependently. Thus we have successfully established stable pcDNA5/FRT/TO-KAP1-HEK293 cell line, which can express KAP1 inducibly. This inducible cell line might be very useful for KAP1 functional studies.

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Abstract

Let R be an IF ring, or be a ring such that each right R-module has a monomorphic flat envelope and the class of flat modules is coresolving. We firstly give a characterization of copure projective and cotorsion modules by lifting and extension diagrams, which implies that the classes of copure projective and cotorsion modules have some balanced properties. Then, a relative right derived functor is introduced to investigate copure projective and cotorsion dimensions of modules. As applications, some new characterizations of QF rings, perfect rings and noetherian rings are given.

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