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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. Source

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. Source

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. Source

Xie L.,YuYao Environmental Protection Bureau | Liu Z.,Ningbo Entry Exit Inspection and Quarantine Bureau | Zhang J.,Ningbo Entry Exit Inspection and Quarantine Bureau | Ma J.,China Academy of Building Research
Journal of Alloys and Compounds | Year: 2010

Bismuth molybdate (Bi3.64Mo0.36O6.55) powders as a novel photocatalyst was prepared using Bi(NO3) 3·5H2O and Na2MoO4· 2H2O as raw materials by a simple low temperature molten salt method at 160 °C for 2 h. The as-prepared samples were characterized with X-ray diffraction (XRD), transmission electron microscopy (TEM) and UV-visible (UV-vis) absorption spectra. The photocatalytic activity of Bi 3.64Mo0.36O6.55(BMO) nanocrystals was evaluated using the photocatalytic oxidation of rhodamine B (RhB) at room temperature under ultraviolet irradiation. The factors affecting the photocatalytic activity, such as photocatalysts concentration, RhB concentration and compressed air as the assisted oxidant species additives, had been studied. © 2010 Elsevier B.V. All rights reserved. Source

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. Source

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