Enantio- and diastereoselective boron conjugate addition to α-alkyl α,β-unsaturated esters.

We developed a copper-catalyzed enantio- and diastereoselective boron conjugate addition to α-alkyl α,β-unsaturated esters under base-free conditions. The approach showed excellent enantioselectivities (87-99% ee) and moderate to good conversions (51-99%), albeit with moderate diastereoselectivities (1 : 1-17 : 1 dr). The synthetic utility of this protocol was demonstrated.

Facile synthesis of a novel magnetic covalent organic frameworks for extraction and determination of five fungicides in Chinese herbal medicines.

A novel magnetic covalent organic framework was synthesized via a one-step coating approach with solvothermal reaction employing 2,4,6-tris(4-aminophen-yl)-1,3,5-triazine and 2,4,6-triformylphloroglucinol as two building blocks by covalent bonding. The prepared magnetic covalent organic frameworks were properly characterized by different techniques and employed as adsorbents of magnetic solid-phase extraction. An analytical method was developed for the simultaneous determination of five fungicides in two Chinese herbal medicine samples via magnetic solid-phase extraction coupled to ultra high performance liquid chromatography with tandem mass spectrometry analysis.

[Construction and application of economy-pollution-environment three-dimensional evaluation model for district].

For deep analysis on the regional environmental economic system, the paper analyzes the mutual relation of regional economy development, environmental quality, environmental pollution, and builds the theoretical basis. Then, the economy-pollution-environment quality three-dimensional coupling evaluation model for district is constructed. It includes economic development level index, environmental pollution index, and environmental quality index.

[Spatial and temporal characteristics of heavy metal concentration of surface soil in Hebin Industrial Park in Shizuishan northwest China].

Unlabelled: Concentrations of Zn, Cu, Cr, Pb and Cd in 96 topsoil samples collected from the northern Hebin Industrial Park were measured by the atomic absorption detector (AAD). Spatial variability was identified by geostatistical analysis with the aid of GS + 3.0 and ArcGIS 9.

[Preparation and identification of OmpW monoclonal antibodies].

Aim: To prepare and characterize the mouse monoclonal antibodies against Vibrio parahaemolyticus OmpW.

Methods: The OmpW amino acid sequence from three diseased Vibrio was analyzed by Bioinformatics. Mice were immunized with r-OmpW which was highly expressed and purified in E.