Time filter

Source Type

Riedel M.,State Office for Rural Development | Schonfeld U.,State Office for Rural Development | Gu J.,Ningbo Entry Exit Inspection and Quarantine Bureau | Braasch H.,Kantstrasse 5
Nematology | Year: 2014

A new Bursaphelenchus species of the xylophilus group was detected in coniferous packaging wood imported with goods from China in 2011. The new species is described herein and compared with other species of the xylophilus group. Bursaphelenchus gillanii sp. n. has a slim body (a = 31 (28-34) and 33 (29-36) in females and males, respectively), ć = 3.8 (3.2-4.5) and 2.1 (1.7-2.5) in females and males, respectively, a large vulval flap, a 5-7 μm long digitate mucro as a continuation of the female tail, excretory pore at or closely posterior to the median bulb, strongly arcuate spicules, 34 (31-37) μm long as measured along the median line, with prominent pointed rostrum and small cucullus. The ITS-RFLP pattern of the new species obtained by digestion of the PCR product with RsaI, HaeIII, MspI, HinfI and AluI is different from other known Bursaphelenchus species. Results of sequencing the ITS1/2 region demonstrate the close relationship of the new species to B. mucronatus and B. xylophilus. © Koninklijke Brill NV, Leiden, 2014.

Jin X.,Xiamen University | Li L.,Xiamen University | Hang W.,Xiamen University | Chen J.,Ningbo Entry Exit Inspection and Quarantine Bureau | Huang B.,Xiamen University
Spectrochimica Acta - Part B Atomic Spectroscopy | Year: 2010

An enclosed device surrounding the argon inductively coupled plasma torch was fabricated to exclude air entrainment and attenuate background interferences. Helium was introduced into the enclosure, and ambient helium plasma was formed stably. Under cold plasma condition, we found that the spectral background decreased about 1 order of magnitude averagely compared with that in typical operation condition. For laser ablation with a Nd:YAG laser, the limits of detection of 28Si, 29Si, 31P, and 32S in an iron matrix were improved significantly; the linearity of their calibration curves was greatly improved as well compared with standard mode and cool mode ICP-MS with no ambient helium. The result indicates that polyatomic interferences from nitrogen, oxygen, hydrogen, carbon, etc. were effectively reduced in helium ambient ICP-MS. © 2010 Elsevier B.V. All rights reserved.

PubMed | Zhejiang Economic and Trade Polytechnic, Ningbo Entry Exit Inspection and Quarantine Bureau and Zhejiang University of Technology
Type: | Journal: Colloids and surfaces. B, Biointerfaces | Year: 2015

Pseudo ternary phase diagrams were constructed to assess the dilutability of thymol microemulsions using non-ionic (Tween 80), cationic (CTAB), and anionic (SDS) surfactants. We successfully constructed a thymol U-type microemulsion system using Tween 80 as surfactant and studied the microstructural transition along the dilution line at a 90/10 surfactant/oil mass ratio, with thymol and ethanol (3:1, w/w) as the oil phase. Differential scanning calorimetry analysis suggested that the microemulsions gradually inverted from the water-in-oil (W/O) (0-20% water) to the bicontinuous (25-35% water), and finally to the oil-in-water (O/W) (40-90% water) microstructures upon dilution, in good agreement with the conductivity measurements, while the rheological results indicated the collapse of rod-like micelles followed by formation of spherical micelles in the O/W region. The activities of the U-type thymol microemulsions are structural dependent. The antimicrobial activity against Escherichia coli and Staphylococcus aureus decreased when the microemulsions transformed from W/O to bicontinuous and O/W structures, while the DPPH scavenging activity increased.

Chen X.,South-Central University for Nationalities | Ren T.,South-Central University for Nationalities | Ma M.,Ningbo Entry exit Inspection and Quarantine Bureau | Wang Z.,Qinzhou University | And 2 more authors.
Electrochimica Acta | Year: 2013

Using carboxylic acid-functionalized single walled carbon nanotubes (SWCNTs-COO-) as an anion and3-butyl-1-[3-(N-pyrrolyl)propyl]imidazolium as a cation, a novel SWCNTs-COO-ionic liquid (SWCNTs-COO-IL) nanocomposite was fabricated successfully. The as-prepared SWCNTs-COO-IL nanocompositewas confirmed with transmission electron microscopy, X-ray photoelectron spectroscopy, UV-vis,FTIR and Raman spectroscopy. The SWCNTs-COO-IL nanocomposite was coated onto a glassy carbonelectrode surface followed by cyclic voltammetric scanning to fabricate a SWCNTs/poly{3-butyl-1-[3-(N- pyrrolyl)propyl] imidazolium ionic liquid} composite film modified electrode (SWCNTs/Poly-IL/GCE).Scanning electron microscope and electrochemical impedance spectroscopy were used to characterizeSWCNTs/Poly-IL/GCE. Electrochemical behaviors of bisphenol A (BPA) at the SWCNTs/Poly-IL/GCE wereinvestigated thoroughly. It was found that an obvious oxidation peak appeared without reduction peakin the reverse scanning, indicating an irreversible electrochemical process. The oxidation peak currentsof BPA were linearly related to scan rate in the range of 20-300 mV s-1, suggesting an adsorption con-trolled process rather than a diffusion controlled process. Differential pulse voltammetry was employedfor the voltammetric sensing of BPA. Experimental conditions such as film thickness, pH value, accu-mulation potential and time that influence the analytical performance of the SWCNTs/Poly-IL/GCE wereoptimized. Under optimal conditions, the oxidation peak current was linearly related to BPA concentra-tion in the range of 5.0 × 10-9to 3.0 × 10-5mol L-1with a detection limit of 1.0 × 10 -9mol L-1(S/N = 3).The developed method was successfully employed for the determination of BPA leaching from plasticdrinking bottle. © 2013 Elsevier Ltd.

Guo X.,Tongji University | Yin D.,Tongji University | Peng J.,Ningbo Entry Exit Inspection and Quarantine Bureau | Hu X.,Tongji University
Journal of Separation Science | Year: 2012

A simple, rapid and environment-friendly technique of single-drop liquid-phase microextraction has been developed for the determination of sulfonamides in environmental water. Several important parameters including stirring rate, extraction solvent, extraction pH, salinity and extraction time were optimized to maximize the extract efficiency. Extraction solvent 1-octyl-3-methylimidazolium hexafluorophosphate [C 8MIM][PF 6] ionic liquid showed better extraction efficiency than 1-butyl-3-methylimidazolium hexafluorophosphate [C 4MIM][PF 6] and 1-octanol. The optimum experimental conditions were: pH, 4.5; sodium chloride content, 36% w/v; extraction time, 20 min. This method provided low detection limits (0.5-1 ng/mL), good repeatability (the RSD ranging from 4.2 to 9.9%, n=5) and wide linear range (1-1500 ng/mL), with determination coefficients (r 2) higher than 0.9989 for all the target compounds. Real sample analysis showed relative recoveries between 63.5 and 115.8% for all the target compounds. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Zhang H.-C.,Tongji University | Yu X.-J.,Ningbo Entry exit Inspection and Quarantine Bureau | Yang W.-C.,Ningbo Entry exit Inspection and Quarantine Bureau | Peng J.-F.,Ningbo Entry exit Inspection and Quarantine Bureau | And 3 more authors.
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2011

A novel analytical method employing MCX (mixed-mode cationic exchange) based solid phase extraction (SPE) coupled with liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed to detect 31 endocrine-disrupting compounds (EDCs) in surface water samples simultaneously. The target EDCs belong to five classes, including seven estrogens, eight androgens, six progesterones, five adrenocortical hormones and five industrial compounds. In order to simultaneously concentrate the target EDCs and eliminate matrix interferences in the water samples, MCX SPE cartridges were employed for SPE, and then followed by a simple and highly efficient three-step sequential elution procedure. Two electrospray ionization (ESI) detection modes, positive (ESI+) and (ESI-), were optimized for HPLC-MS/MS analysis to obtain the highest sensitivity for all the EDCs. The limits of detection (LODs) were 0.02-1.9ngL -1, which are lower than or comparable to these reported in references. Wide linear ranges (LOD-100ngL -1 for ESI+ mode, and LOD-200ngL -1 for ESI- mode) were obtained with determination coefficients (R 2) higher than 0.99 for all the compounds. With five internal standards, good recoveries (84.4-103.0%) of all the target compounds were obtained in selected surface water samples. The developed method was successfully applied to investigate the EDCs occurrence in the surface water of Shanghai by analyzing surface water samples from 11 sites. The results showed that nearly all the target compounds (30 in 31) were present in the surface water samples of Shanghai, of which three industrial compounds (4-t-OP, BPA, and BPF) showed the highest concentrations (median concentrations were 11.88-23.50ngL -1), suggesting that industrial compounds were the dominating EDCs in the surface water of Shanghai, and much more attention should be paid on these compounds. Our present research demonstrated that SPE with MCX cartridges combined with HPLC-MS/MS was convenient, efficient and reliable for multiclass analysis of EDCs in surface water. © 2011 Elsevier B.V.

Gu Y.-Y.,Tongji University | Yu X.-J.,Ningbo Entry exit Inspection and Quarantine Bureau | Peng J.-F.,Ningbo Entry exit Inspection and Quarantine Bureau | Chen S.-B.,Ningbo Entry exit Inspection and Quarantine Bureau | And 3 more authors.
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2014

This study aimed to develop a sensitive and reliable multi-residue method for the determination of trace amounts of endocrine disrupting chemicals including five phthalate esters (PAEs), five monoalky phthalate esters (MPEs), four alkylphenols (APs) and bisphenol A (BPA) in seafood. Ultrasonic liquid extraction was selected for extraction based on acetonitrile, instead of frequently-used n-hexane, due to its lower background of PAEs. Application of solid phase extraction (SPE) with primary secondary amine (PSA, 1. g/6. mL) cartridge achieved the relatively low matrix effects for MPEs and BPA in seafood. To our knowledge, it is the first study reporting about simultaneous extraction and purification of PAEs, MPEs, APs and BPA in biota samples. To obtain the maximum sensitivity, both liquid chromatography tandem mass spectrometry (LC-MS/MS) and gas chromatography tandem mass spectrometry (GC-MS/MS) were applied for analysis. This method was validated and tested on fish, mollusk and prawn. Sufficient linearity was verified by Mandel's fitting test for the matrix-matched calibrations used in this study for MPEs, APs and BPA, between 0.5. ng/g and 200. ng/g or 400. ng/g. And correlation coefficients of all calibrations suppressed 0.99 for all analytes. Good recoveries were obtained, ranging from 60% to 127% for most compounds. The sensitivity was good with method detection limits (MDLs) of 0.015-2.2. ng/g wet weight (ww) for all compounds. Most MDLs are much lower than those in previous reports. The sensitive method was then applied on real fish, mollusk and prawn samples from the Yangtze River Delta sea area (China), and all the target compounds were detected with the maximum concentrations of PAEs, MPEs, APs and BPA up to 219.3. ng/g ww, 51.4. ng/g ww, 62.0. ng/g ww and 8.6. ng/g ww, respectively. © 2014 Elsevier B.V.

Luo C.,Ningbo Entry Exit Inspection and Quarantine Bureau | Dai S.,Ningbo Entry Exit Inspection and Quarantine Bureau | Ye J.,Key Laboratory of Zhejiang Petrochemical Product Quality and Safety Testing Technology Research
Advances in Energy Science and Equipment Engineering - Proceedings of International Conference on Energy Equipment Science and Engineering, ICEESE 2015 | Year: 2015

Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu Rare Earth Elements in crude oil were determined by ICP-MS. The oil sample was treated with high-pressure digestion. The digestion degree of the crude oil was monitored by determining the intensity of C element at 193.027 nm by ICP, which solved the problem of equipment damage and pollution or result deviations caused by incomplete digestion. The polyatomic ion effect was eliminated by collision cell technique and the matrix effect was compensated by selecting suitable elements as the internal standard elements for the determination. The results showed that the detection limits were 0.01 μg/kg ∼0.7 μg/kg, and values of recovery were in the ranges of 80.4%%∼105.2%. The method was suitable for determining the trace rare earth elements in crude oil with the features of low detection limit, rapid determination and convenience. © 2015 Taylor & Francis Group, London.

Chuan L.,Ningbo Entry Exit Inspection and Quarantine Bureau | Wu B.,Ningbo Entry Exit Inspection and Quarantine Bureau | Zhang Y.,Ningbo Entry Exit Inspection and Quarantine Bureau
Asian Journal of Chemistry | Year: 2013

A rapid method was developed for the determination of the vanadium, manganese, nickel, copper, silver, cadmium, tin, barium and lead in engine oil by inductively coupled plasma mass spectrometry (ICP-MS). Direct sample introduction was performed with a special organic sample kit after dilution of the high viscosity engine oil with a suitable organic solvent. The sample up-take rate was optimized be to 50-100 μL/min with a continuous dose of additional O2 (20 %) in the aerosol gas to prevent the deposition of carbon on the sampler and the extinction of plasma by the high viscosity of engine oil. The detection limits were less than 3.18 ng/g. The relative standard deviations were less than 4.9 %. The spiked recoveries were 90.1-101.7 %. © 2013 Asian Journal of Chemistry.

Wang H.,Ningbo Entry Exit Inspection and Quarantine Bureau | Lin Z.-X.,Ningbo Entry Exit Inspection and Quarantine Bureau | Wu B.-L.,Ningbo Entry Exit Inspection and Quarantine Bureau
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis | Year: 2013

The present article adopts wavelength-dispersive X-ray fluorescence spectrometry to measure elements of P, S and Cl in 98 engine oil samples from America, Germany and Japan and including SM, SN, CI and CH API grade. Proportional relationship of Zn/P, S/Mo and Ca/Mg illustrated the correlation between experimental data and additive contents. The experiment indicates that the concentration levels of Zn, P, Ca, S, Mg and Mo were 0.09%~0.17%, 0.07%~0.15%, 0.13%~0.43%, 0.20%~0.47%, 0.04%~0.15% and 0.01%~0.05% respectively, among which the Ca, S, P and Zn were the main elements of engine oil, Mg and Mo exist in high quality level engine oil, while Nb, W, Ti and Na were present in individual engine oil.

Loading Ningbo Entry Exit Inspection and Quarantine Bureau collaborators
Loading Ningbo Entry Exit Inspection and Quarantine Bureau collaborators