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One divided into two combined into one: The catalytic conversion of furfural into a 2,5-furandicarboxylic acid-based polyester, linked by the disproportionation of furoate to furan and 2,5-furandicarboxylate, is reported. In this manner, all carbons are utilized, demonstrating the success of combining a platform molecule from C(5) sugars (furfural) to one from C(6) sugars (2,5-FDCA).

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A novel solid acid catalyst, sulfonated chloromethyl polystyrene (CP) resin (CP-SO 3 H-1.69), was synthesized by partially substituting chlorine groups (ÀCl) of CP resin with sulfonic group(ÀSO 3 H). This new type solid acid contains not only acid sites, but also cellulose-binding sites (ÀCl). A high yield of levulinic acid up to 65.5 % was obtained by converting microcrystalline cellulose over CP-SO 3 H-1.69. The high catalytic activity of CP-SO 3 H-1.69 was attributed to high amount of sulfonic group and chlorine on the catalyst, which is essential to keep the catalyst with great affinity to substrate.As the major component of plant biomass and nongrain feedstock, cellulose is extensively considered as an ideal raw material for the future for the production of biofuels and chemicals. [1] Cellulose is composed of glucose monomer units connected through b-1,4-glycosidic bonds and has a recalcitrant structure as a result of the existence of large amounts of intraand intermolecular hydrogen bonds among the chains of cellulose. These strong bonds provide researchers with a great challenge on how to effectively convert cellulose into some useful compounds. [2] In recent years, many catalytic systems, including ionic liquids, [3][4][5] aqueous media, [6,7] biphasic media, [8][9][10] and sub-and supercritical fluids, [11,12] have been developed, and various cellulose degradation products such as glucose [13][14][15][16][17] 5-hydroxymethylfurfural (HMF), [18][19][20] levulinic acid (LA), [21][22][23] 5-chloromethylfurfural, [24,25] ethylene glycol, [26][27][28] propylene glycol, [29] and sugar alcohols [30][31][32] have been obtained. Without underestimating the value of other cellulose degradation products, LA production from cellulose has received significant attention owing to the fact that LA not only has high chemical reactivity, which makes it suitable for the production of various organic chemicals, but it also has the potential to serve as a chemical intermediate in the production of biofuels through existing petrochemical technologies. For example, in combination with phenol, LA is a starting material in the synthesis of diphenolic acid, which has great potential to replace bisphenol A. [33,34] Furthermore, some fuel additives such as levulinic esters, [35] methyltetrahydrofuran (MTHF), [36] and valeric esters [37,38] can be synthesized from LA. g-Valerolactone (GVL), a hydrogenation product of LA, can be converted into liquid alkenes ranging from C 8 to C 24 , which could serve as fuel blendstocks. [39] Mineral acids, including H 2 SO 4 , [37,38,[40][41][42][43][44][45][46][47] HCl, [48][49][50][51] and HBr, [52,53] are used as homogeneous catalysts to produce LA from biomass feedstocks. Among these catalytic systems, in the Biofine process developed by Biofine Renewables LLC exhibits excellent performance in the production of LA (0.5 kg LA per kg cellulose). [46,47] The Biofine process is clearly a relatively economic process for the production of LA. However, this process also has some disadvantages because...

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Nanohydroxyapatite (n-HA)/zinc oxide (ZnO) complex was synthesized by a direct precipitation method, and the antibacterial capability and antibacterial mechanism of this complex were investigated in this article. Transmission electron microscope (TEM), Fourier transform infrared, X-ray photoelectronic spectroscopy (XPS), and X-ray diffraction (XRD) were used to analyze the materials. In addition, the antibacterial capacity of n-HA/ZnO complex was examined by bacteriolytic plate, inhibition effect, and antibacterial rate assays under light or without light. Furthermore, agarose gel electrophoresis of plasmid DNA (pUC18) was used to study biocidal action of this complex. The results of TEM observation revealed that the complex's rods had a single crystalline obelisk-like hexagonal wurtzite structure and the crystal retained the nanometer size. XRD analysis indicated that the phase of ZnO appeared and the lattice parameters of n-HA and ZnO changed. XPS spectra showed that the bonding energy of Ca, P, and O atoms changed in the complex. The analyses also showed that the two phases of ZnO and n-HA combined closely. Further, the results of the antibacterial test revealed that this complex possessed strong antibacterial capability; the antibacterial rate was 99.45% to S. aureus and 95.65% to E. coli under light, respectively. The antibacterial activity of this complex under light was better than without light, which was attributed to the generation of .OH under light. From the agarose gel electrophoresis, the dissolving solution of this complex could catalyze the cleavage of pUC18.