Metal-free visible-light-driven cascade cyclization reaction to synthesize 2-oxindoles via benzoyl and phenylsulfinyl radicals with acrylamide derivatives.

A metal-free visible-light-driven cascade cyclization reaction to synthesize 3-methyl-3-acetophenone-2-oxindoles and 3-methyl-3-(methylsulfonyl)benzene-2-oxindoles in yields up to 96% and 99%, via benzoyl and phenylsulfinyl radicals with acrylamide derivatives is reported, respectively. Extensive studies, including gram-scale, radical capture and isotope experiments, were performed to indicate that the reaction may involve a radical process.

[Direct determination of copper, iron and sodium in high-purity alumina by slurry introduction furnace atomic absorption spectrometry with Smith-Hieftje background correction].

Direct determination of copper, iron and sodium in high-purity alumina was performed by slurry-furnace atomic absorption spectrometry with Smith-Hieftje background correction (S-H-GFAAS). Instrument conditions of GFAAS such as pyrolysis, atomization and hollow cathode lamp current by S-H background correction were optimized, and the optimal experimental conditions were selected. Calibration was performed using aqueous standards method for sample analysis. The accuracy of the proposed method was shown for the case of Al2O3 (AKP-30), and compared with those obtained by furnace atomic absorption spectrometry subsequent to decomposition by sulfuric acid in PTFE pressure vessels. The results were in agreement well with values found in the literature by different methods. It is a simple, convenient and accurate method and it is suitable for the rapid analysis of trace element in alumina. The linear regression coefficients of the calibration curves were better than 0.999 0. The detection limits were 0.66, 2.5 and 0.13 ng x g(-1), respectively, with a relative standard deviation being not more than 5.2%.

[Research advance in slurry introduction for graphite furnace atomic absorption spectrometry].

Slurry introduction graphite furnace atomic absorption spectrometry combining the significant advantages of the solid and liquid sampling methods is already considered as a mature technique. It was widely utilized for metal determination in trace and even ultra trace analysis in organic and inorganic complicated matrix, even for routine analysis. Methodology of the analysis of various materials using slurry furnace atomic absorption spectrometry was reviewed in the present paper in late 10 years. Techniques of slurry preparation (liquid media, stabilizing agents, mass/volume ratio, particle size and slurry homogenization systems), the chemical modification, background correctors, calibration, precision and trueness of analysis were described in detail. The developing trend has also presented. Eighty one references were cited.

[Influence of meliorated AS-PCR primer for ABO genotyping].

OBJECTIVE: To improve the correct rate of ABO genotyping by meliorating AS-PCR primer. METHODS: The primer P1 was changed into primer P1' by substituting the fifth base G for C of 3' end and the ABO genotyping results of primer P1 and P1' was compared and analysed. RESULTS: The non-specific product of OO typing is reducing and the wrong genotyping of OO and AO was avoided by meliorating AS-PCR primer. CONCLUSION: The rates of wrong ABO genotyping results could be effectively reduced by using altering primer P1'.

[Identification of six species of sarcosaphagous flies (Diptera) by sequence analysis of cytochrome oxidase subunit I gene (COI) in Weifang].

OBJECTIVE: To identify sarcosaphagous flies and their larvae, pupa. METHODS: Sarcosaphagous flies and their larvae, pupas were collected from human corpses and their surroundings in the Weifang city. A 304 bp region in COI gene was analyzed by mtDNA sequencing. RESULTS: The studied region showed no sequence divergence within same species and significant difference were found between different species in all samples. CONCLUSION: It is a practical approach to identify these Sarcosaphagous flies and their larvae, pupas by sequence analysis of the 304bp region of the COI in mtDNA.

[Genetic polymorphism of 9 STR loci in Han nation population in Shandong Province].

OBJECTIVE: To study genetic polymorphism of 9 STR loci in Han nation population in Shangdong Province. METHODS: We investigated 100 unrelated individuals of Han nation population in Shandong Province and studied their genetic distribution of 9 STR loci and Amelogenin locus. Primers of 10 loci were labeled with the NHS-ester fluorescent dye 5-FAM (blue), Joe (green) or NED (yellow). The data of Han nation population were generated by multiple amplification and subjected to GeneScan, genotype and genetic distribution analysis. RESULTS: 83 alleles and 220 genotypes were observed, with the corresponding frequency of 0.0050-0.4050 and 0.0100-0.2100. The average of heterozygosity was 0.7778, the accumulated discrimination power was 0.9999. The accumulated probability of exclusion paternity was 0.9999. The polymorphism information content was 0.5823-0.8396. CONCLUSIONS: Chi-Square test indicated that the distribution of genotypes agreed with Hardy-Weinberg equilibrium.