In order to acquire the pollution feature and regularities of distribution of metals in the topsoil within the sixth ring road in Beijing, a total of 46 soil samples were collected, and the concentrations of twelve elements (Nickel, Ni, Lithium, Li, Vanadium, V, Cobalt, Co, Barium, Ba, Strontium, Sr, Chrome, Cr, Molybdenum, Mo, Copper, Cu, Cadmium, Cd, Zinc, Zn, Lead, Pb) were analyzed. Geostatistics and multivariate statistics were conducted to identify spatial distribution characteristics and sources. In addition, the health risk of the analyzed heavy metals to humans (adult) was evaluated by an U.S. Environmental Protection Agency health risk assessment model. The results indicate that these metals have notable variation in spatial scale. The concentration of Cr was high in the west and low in the east, while that of Mo was high in the north and low in the south. High concentrations of Cu, Cd, Zn, and Pb were found in the central part of the city. The average enrichment degree of Cd is 5.94, reaching the standard of significant enrichment. The accumulation of Cr, Mo, Cu, Cd, Zn, and Pb is influenced by anthropogenic activity, including vehicle exhaustion, coal burning, and industrial processes. Health risk assessment shows that both non-carcinogenic and carcinogenic risks of selected heavy metals are within the safety standard and the rank of the carcinogenic risk of the four heavy metals is Cr > Co > Ni > Cd.

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A copper-catalyzed, ligand-free intramolecular C−N coupling of (E)-2-(2-bromophenyl)-3-arylacrylamides has been developed. This protocol provides an efficient and practical synthetic route for the biologically important (E)-3-arylideneindolin-2ones from o-bromophenylacetic acids and aromatic or conjugated alkenyl aldehydes. Readily available starting materials, mild and noble metal-free conditions, high efficiency, and good tolerability for phenolic hydroxyl groups make this approach attractive and applicable.

The synthesis, structure confirmation, stability and isomerization features of suffrutines A, B and their N-fused analogues were reported. Biological tests showed that the introduction of nitrogen atom might be beneficial to the anticancer activity.

A facile and practical approach for the synthesis of natural coumestans and derivatives starting from 2′,4′-dihydroxyl-3-arylcoumarins has been developed. The process involved a seqential intramolecular dehydrogenation/oxa-Micheal reaction efficiently promoted by 1,8-diazabicyclo[5.4.0]­undec-7-ene at 40 °C under metal- and ligand-free conditions with good functional group compatibility.

Summary In this study, the concept of biomass-based direct air capture is proposed, and the aminoguanidine CO 2 chemical sorbent 2,5-furan-bis(iminoguanidine) (FuBIG) was designed, synthesized, and elucidated for the physicochemical properties in the process of CO 2 capture and release. Results showed that the aqueous solution of FuBIG could readily capture CO 2 from ambient air and provided an insoluble tetrahydrated carbonate salt FuBIGH 2 (CO 3 ) (H 2 O) 4 with a second order kinetics. Hydrogen binding modes of iminoguanidine cations with carbonate ions and water were identified by single-crystal X-ray diffraction analysis. Equilibrium constant (K) and the enthalpies (ΔH) for CO 2 absorption/release were obtained by thermodynamic and kinetic analysis (K 7 = 5.97 × 10 4 , ΔH 7 = −116.1 kJ/mol, ΔH 8 = 209.31 kJ/mol), and the CO 2 -release process was conformed to the geometrical phase-boundary model (1-(1-α) 1/3 = kt). It was found that the FuBIGH 2 (CO 3 ) (H 2 O) 4 can release CO 2 spontaneously in DMSO without heating. Zebrafish models revealed a favorable biocompatibility of FuBIG.

Complexity and versatility of problems encountered in the process in order to improve the traditional data exchange platform, "Proxy + server "loosely coupled mode data exchange platform system, system using a messaging service to solve complex interactive control information in the data exchange process. Solve the data exchange process in a variety of data transmission and efficient mutual use of data transmission services. System implementation process draws on SOA architecture Thought, part of the using of the core technology of SOA, Clear hierarchy of the system. Has good versatility and maintainability , greatly reduce the difficulty of system development.