Botanical Study on EarlyCretaceous Coal-Bearing Strata in Northeast China and Inner Mongolia, China

Study on the fossil plants and the palynoiogical assemblage is the basic botanical research on the coalbearing strata. The practice indicate that comprehensive data from the study on the fusinized wood fossil, the phyterals and the analysis of dispersed cuticles will effecuvely improve the level of the study on the coal-bearing strata as a whole.     

Cuticular hydrocarbons of the eastern subterranean termite,Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae)

Major cuticular hydrocarbon components in several castes ofReticulitermes flavipes (Kollar) have been identified and quantitated. Types of hydrocarbons present includen-alkanes, 2-methylalkanes, 3-methylalkanes, 5-methylalkanes, an alkene, and an alkadiene, with a range in carbon numbers from C₂₁ to C₂₆, This is the first report on insect cuticular hydrocarbons in which both 2- and 3-methylalkanes are present, as well as the first report of an insect with a conjugated alkadiene.     

华南中泥盆世成煤植物

依据煤中植物残体分析并结合煤系地层植物群组合特征，对华南中泥盆世成煤植物进行了论证．研究表明形成角质残植煤的植物具有多样性，主要为裸蕨类和原始石松类，其中戴肯涅带蕨（Ｔａｅｎｉｏｃｒａｄａｄｅｃｈｅｎｉａｎａ）在成煤植物群落中占优势地位．     

Bio‐Inspired,Water‐Soluble to Insoluble Self‐Conversion for Flexible,Biocompatible, Transparent,Catecholamine Polysaccharide Thin Films

In nature, a variety of functional water‐insoluble organic materials are biologically synthesized in aqueous conditions without chemical additives and organic solvents. Insect cuticle, crustacean shells, and many others are representative examples. The insoluble materials are prepared by enzyme reactions and programmed self‐assembly in water from water‐soluble precursors. If the water‐basis could be adapted, environment‐friendly strategy developed in nature, many problems caused by the vast consumption of petroleum‐based olefin materials could be solved or significantly attenuated. Here, the spontaneous formation of water‐insoluble, biocompatible films from a water‐soluble polymer is demonstrated without using any chemical additives and organic solvents. It is found that a water‐soluble chitosan–catechol polymeric precursor is spontaneously self‐converted to flexible water‐insoluble thin film by simple dehydration. The preparation of mechanically robust, water‐insoluble, flexible, transparent chitosan–catechol film is a completely unexpected result because most water‐soluble polymers exist as powders when dehydrated. The film can be used as a bag similar to polyvinyl one and is multifunctional and biocompatible for drug delivery depots and tissue engineering applications.     

Unexpected strength and toughness in chitosan-fibroin laminates inspired by insect cuticle

A material inspired by natural insect cuticle and composed of chitosan and fibroin is created. The material exhibits the strength of an aluminum alloy at half its weight, while being clear, biocompatible, biodegradable, and micromoldable. The bioinspired laminate exhibits strength and toughness that are ten times greater than the unstructured component blend and twice that of its strongest constituent.     

Extreme Optical Properties Tuned Through Phase Substitution in a Structurally Optimized Biological Photonic Polycrystal

Biological photonic structures evolved by insects provide inspiring examples for the design and fabrication of synthetic photonic crystals. The small scales covering the beetle Entimus imperialis are subdivided into irregularly shaped domains that mostly show striking colors, yet some appear colorless. The colors originate from photonic crystals consisting of cuticular material and air, which are geometrically separated by a triply periodic D‐surface (diamond). The structure and orientation of the photonic crystals are charactized and it is shown that in colorless domains SiO₂ substitutes the air. The experimental results are incorporated into a precise D‐surface structure model used to simulate the photonic band structure. The study shows that the structural parameters in colored domains are optimized for maximum reflectivity by maximizing the stop gap width. The colorless domains provide a biological example of how the optical appearance changes through alteration of the refractive index contrast between the constituting phases.