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The Mesoproterozoic Kawabulake Group, which is unconformably overlain by the Lower Cambrian Huangshan Formation and conformably overlies the Mesoproterozoic Xingxingxia Group in the Eastern Tianshan area, NW China, is comprised mainly of siltstone, slate, sandstone and phyllite. New geochemical data for the clastic rocks from the Kawabulake Group were investigated to constrain the provenance and weathering history of the source rocks, in order to evaluate the tectonic evolution of the Eastern Tianshan area. Kawabulake Group rocks are compositionally similar to PAAS (average Post-Archean Australian Shale), indicating derivation from a felsic source that is characterized by depletion in some HFSEs such as Nb, Ta and Ti. The Chemical Index of Alteration (CIA) for the sandstone, siltstone and slate samples (CIA = 60 on average) suggests intensely weathered sources. Light REE-enrichment patterns ((La/Yb) = 4-20) coupled with negative Eu anomalies (Eu/Eu* between 0.44 and 0.89 with an average of 0.62) are similar to those of PAAS, consistent with cratonic sources. The major and trace element compositions imply a dominantly Precambrian felsic source region with a minor contribution from mafic materials. The Sr-Nd isotopic compositions and the ages of T (~3.4, 2.5-1.8, 1.2 and 1.0 Ga) are consistent with the evolutionary history of Kuluketage in the northern Tarim, suggesting that the Tarim Craton was the main source area for the Kawabulake Group. [ABSTRACT FROM AUTHOR]

Based on polyethylene glycol modified single-walled carbon nanotubes, a novel sol-gel fiber coating was prepared and applied to the headspace microextraction of chlorinated organic carriers (COCs) in textiles by gas chromatography-electron capture detection. The preparation of polyethylene glycol modified single-walled carbon nanotubes and the sol-gel fiber coating process was stated and confirmed by infrared spectra, Raman spectroscopy, and scanning electron microscopy. Several parameters affecting headspace microextraction, including extraction temperature, extraction time, salting-out effect, and desorption time, were optimized by detecting 11 COCs in simulative sweat samples. Compared with the commercial solid-phase microextraction fibers, the sol-gel polyethylene glycol modified single-walled carbon nanotubes fiber showed higher extraction efficiency, better thermal stability, and longer life span. The method detection limits for COCs were in the range from 0.02 to 7.5 ng L (S/N = 3). The linearity of the developed method varied from 0.001 to 50 μg L for all analytes, with coefficients of correlation greater than 0.974. The developed method was successfully applied to the analysis of trace COCs in textiles, the recoveries of the analytes indicated that the developed method was considerably useful for the determination of COCs in ecological textile samples. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Solid-phase microextraction (SPME) based on carboxylated single-walled carbon nanotube fibers was used to extract several chlorophenols (CPs) and organochlorine pesticides (OCPs) from aqueous samples prior to their determination by GC with electron capture detection. The main parameters affecting microextraction (temperature, time, stirring rate and salting-out effect) and the conditions of the thermal desorption in the GC injector were optimized. Compared with commercial SPME fibers, the fiber presented better selectivity and sensitivity. Linear response was found for the concentration range between 2 and 1000 ng L (20-1000 ng L for CPs), and the limits of detection were in the range from 0.07 to 4.36 ng L. The repeatability expressed as relative standard deviation ranged from 4.1 % to 8.2 % and the fiber-to-fiber reproducibility for four prepared fibers was between 6.5 % and 10.8 %. The method was successfully applied to the analysis of CPs and OCPs in lake water and waste water samples. Recovery was tested with spiked lake water and waste water samples, with values ranging from 89.7 % to 101.2 % in case of waste water samples. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The Fourier transform infrared (FTIR) spectra of the cells of two photosynthetic H2-producing strains, Rhodoblastus acidophilus and Rhodobacter capsulatus, as well as their extracellular polymeric substances (EPS), were evaluated. The FTIR spectra of R. capsulatus and its EPS during its cultivation were also recorded. The main peaks in the spectra, including 1,080 cm−1 (carbohydrates), 1,250 cm−1 (nucleic acids), 2,830–2,930 cm−1 (lipids), 1,660–1,535 cm−1 (Amide I and II of proteins), were observed. The relative heights of these peaks in the spectra of the two strains were different, showing the difference in contents of various components in the cells or EPS. The ratios among the main components in the EPS obtained from the FTIR spectra were in good agreement with those from a conventional quantitative chemical analysis. As an easy, rapid, and direct technique, the FTIR spectroscopy could be used to characterize the components and their relative contents of EPS of photosynthetic bacteria. [ABSTRACT FROM AUTHOR]

Following publication of the original article [1], the authors reported an error in Schemes 1 and 2 and repeated line in subsection "Bis(ligand) nickel(II) chelate (NiL12)". [ABSTRACT FROM AUTHOR]

Background: The general approach to the synthesis of metal complexes begins with ligand synthesis, followed by ligand reaction with metal salts to afford organometallic complexes. Our research group first reported a one-pot multicomponent synthesis of chiral oxazolinyl–zinc complexes, in the presence of a large amount of ZnCl2 (0.4–2.6 equiv.), with the yields of some products reaching 90%. Results: Our prior strategy was extended to use copper, cobalt, nickel, manganese, palladium or platinum salts as the third component. The one-step method used 1.0 equivalent of a metal salt, such as M(OAc)2·nH2O or MCl2·nH2O (M: Cu, Co, Ni, Pd or Pt, n = 1, 2 or 4), as a reagent to generate chiral salicyloxazoline complexes 1–8 in the reaction of 2-cyanophenol with different d- and l-amino alcohols. Conclusion: Complexes 1–8 were obtained using a one-pot method with a sequential strategy. The reaction outcome was demonstrated for three-component reactions between metal salts, amino alcohols and 2-hydroxybenzonitrile to afford organometallic complexes in good yields (65–95%). [ABSTRACT FROM AUTHOR]

A correction to the article "FTIR-spectral analysis of two photosynthetic hydrogen-producing strains and their extracellular polymeric substances," by Guo-Ping Sheng, Han-Qing Yu and Cheng-Ming Wang, published November 2006 issue of"Appl Microbiol Biotechnol," is presented.