Yu-Zhong Wang

Bio: Yu-Zhong Wang is an academic researcher from Sichuan University. The author has contributed to research in topics: Fire retardant & Limiting oxygen index. The author has an hindex of 83, co-authored 786 publications receiving 27502 citations. Previous affiliations of Yu-Zhong Wang include Zhengzhou University & University of Kentucky.

A stable silicon(0) compound with a Si=Si double bond.

Abstract: Dative, or nonoxidative, ligand coordination is common in transition metal complexes; however, this bonding motif is rare in compounds of main group elements in the formal oxidation state of zero. Here, we report that the potassium graphite reduction of the neutral hypervalent silicon-carbene complex L:SiCl4 {where L: is:C[N(2,6-Pri2-C6H3)CH]2 and Pri is isopropyl} produces L:(Cl)Si–Si(Cl):L, a carbene-stabilized bis-silylene, and L:Si=Si:L, a carbene-stabilized diatomic silicon molecule with the Si atoms in the formal oxidation state of zero. The Si-Si bond distance of 2.2294 ± 0.0011 (standard deviation) angstroms in L:Si=Si:L is consistent with a Si=Si double bond. Complementary computational studies confirm the nature of the bonding in L:(Cl)Si–Si(Cl):L and L:Si=Si:L.

A stable, neutral diborene containing a B=B double bond.

Abstract: The syntheses and molecular structures of four compounds are reported: 1 (RBBr3), 2 (R(H)2B−B(H)2R), 3 (R(H)BB(H)R), and 4 (RBH3) (R = :C{N(2,6-Pri2C6H3)CH}2). These compounds were characterized by single-crystal X-ray diffraction, 1H and 11B NMR, and elemental analyses. Compounds 2 and 3 were prepared by the KC8 reduction of 1 in Et2O. Compound 3 is the first structurally characterized neutral diborene (mean BB: 1.560(18) A). The nature of the BB double bond in 3 was delineated by DFT computations.

A review on flame retardant technology in China. Part I: development of flame retardants

Abstract: This paper provides an insight into some developments in flame retardants for different polymeric materials in China, primarily based on the publications that have appeared in the last 15 years. It focuses on the following aspects: halogen-containing flame retardants, inorganic flame retardants (e.g. metal oxides and hydroxides, silicon-containing materials, ammonium polyphosphate, red phosphorus, and expandable graphite), and organic flame retardants (e.g. aliphatic and aromatic phosphonates, nitrogen-containing organics, and multi-element organics). The inherently flame-retardant polymer systems are also reviewed. The exploration of the novel flame retardants and flame-retardant systems provides a powerful basis for the construction of flame-retardant technologies and industrial applications in China. Copyright © 2009 John Wiley & Sons, Ltd.

Cellulose nanomaterials review: structure, properties and nanocomposites

Abstract: This critical review provides a processing-structure-property perspective on recent advances in cellulose nanoparticles and composites produced from them. It summarizes cellulose nanoparticles in terms of particle morphology, crystal structure, and properties. Also described are the self-assembly and rheological properties of cellulose nanoparticle suspensions. The methodology of composite processing and resulting properties are fully covered, with an emphasis on neat and high fraction cellulose composites. Additionally, advances in predictive modeling from molecular dynamic simulations of crystalline cellulose to the continuum modeling of composites made with such particles are reviewed (392 references).

An overview of N-heterocyclic carbenes

Abstract: The successful isolation and characterization of an N-heterocyclic carbene in 1991 opened up a new class of organic compounds for investigation. From these beginnings as academic curiosities, N-heterocyclic carbenes today rank among the most powerful tools in organic chemistry, with numerous applications in commercially important processes. Here we provide a concise overview of N-heterocyclic carbenes in modern chemistry, summarizing their general properties and uses and highlighting how these features are being exploited in a selection of pioneering recent studies.