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In this work, surface molecularly imprinted polymers (SMIPs) were prepared as a specific sorbent to remove the limonin from the lemon juice for the first time, and then the MIPs containing limonin were directly made into a water-soluble gel to treat inflammation of mice. The resulting polymers were characterized by scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectrometer spectra. And the polymerization conditions and adsorption performances of the resultant nanomaterials were further investigated in detail. Results showed that the MIPs have higher adsorption capacity (27.72 mg/g) compared with surface molecularly non-imprinted polymers (NIPs) (8.12 mg/g). The selectivity experiment indicated that the polymers had excellent selective recognition for limonin and the selectivity factors were calculated as 2.75 and 1.83 for nomilin and obakunone, respectively. The MIPs were successfully used as adsorbent for selectively removing limonin from lemon juice and the MIPs extracted almost all the limonin from lemon juice according to the HPLC results. Furthermore, the MIPs with limonin were processed into water-soluble gel, which can be used to reduce the inflammation and enhance wound healing of model mice.

Carbons deposited on the filter after the reactor of hydrocracking (US-Sludge) and in the heat exchanger (DS-Sludge) in a commercial H-Oil process were analyzed through the elemental analysis, XRD, SEM, optical microscope, 13 C-NMR and Raman spectroscopy to elucidate their formation mechanism. Heat treatment of sludge and oil products recovered from the commercial process was performed at 698 K of a reaction temperature. XRD showed the presence of Fe 1− x S, NaCl, and CaSO 4 as well as carbon (2 Θ = 26.6°) in US-Sludge. The carbon showed medium and fine mosaic textures surrounding the isotropic grains. DS-Sludge showed mixed texture of domain and flow surrounding the fine mosaic grains. The sludge consisted of stacked carbon flakes with a number of pores on the surface. EDX showed dominant presence of NaCl and CaO particles in the mosaic region. Heat treatment of asphaltene in the product mixed with US-Sludge gave the same appearance to that of DS-Sludge. US- and DS-Sludge are concluded to be formed through the respective carbon formation in the reactor and to be separated on the filter and on the heat exchanger surface, respectively. The carbon particles produced in the reactor collect contaminant Fe 1− x S and CaSO 4 particles to form the agglomerate where the growth and coalescence of the anisotropic spheres are very restricted to form the fine mosaic texture as observed in the US-Sludge. In contrast, the carbonization of the major precipitated heavy aromatic component leads to the domain or flow anisotropic texture through rather free growth and coalescence of anisotropic spheres on the surface of the heat exchanger wall. Although some parts of precipitated component together with US-Sludge give mosaic texture through the restricted growth and coalescence of anisotropic sphere by the presence of reactive fine solids.

6-Aminohexanoate-dimer hydrolase (EII) and its analogous protein (EII′), of Flavobacterium sp. K172 are composed of 392 amino acids, in which 47 are different. The enzyme activity of EII′ toward 6-aminohexanoate dimer is approximately 0.5% of that of EII. We have constructed various hybrids of the two genes by exchanging fragments flanked by conserved restriction sites such as Pvu II, Bgl II, Sal I, and Bam HI (respectively 74, 483, 771, and 1,141 bp downstream of the initiation codon), and purified their gene products to homogeneity. Hyb-12 protein, which was obtained by the replacement of the Bgl II- Sal I region of the EII′ with the corresponding region of EII, had 12 times higher specific activity towards the 6-aminohexanoate dimer and its related substrates than EII′ protein. Hyb-10, which was composed of the N-terminal - Bgl II regions of EII′ and the Bgl II-C terminal region of EII, had activity toward these substrates nearly equal to the activity of the EII enzyme. Comparisons of the activity toward 6-aminohexanoate dimer and its analogues has demonstrated that EII, EII′, and their hybrid enzymes are highly active only toward the substrates that contain 6-aminohexanoate as the N-terminal residue, while the recognition of the C-terminal residue in the substrate was not stringent. The substrate specificity, pH-activity profile, and heat stability of these enzymes varied slightly.

A new thermosetting pitch resin consisting of condensed aromatic nuclei cross-linked with methylene bridges was prepared by polymerization of a mixture of an aromatic rich fraction from fluid catalytic cracking oils and 1,4-benzenedimethanol at 120℃ with p-toluenesulfonic acid as catalyst.Carbon fiber/resin(CFR)and carbon fiber paper/resin(CFPR)composites were prepared by the hot-pressing method.No remarkable changes in mechanical properties were found when the composites were heated at 250℃ for 10h and 300℃ for 2h and soaked in strong acids or bases for 1 to 70h at room temperature,suggesting that the composites had good thermal stability and resistance to chemical attack.The CFR and CFPR specimens were converted into C/C composites without fissures or cleavages between the pitch resin carbon and carbon fibers by further heat treatment from 950 to 1000℃ under N2 atmosphere.The length of carbon fiber pulled out from the matrix during fracture was of the order of 10μm as seen in SEM photos,indicating that the pitch resin adhered well to the carbon fibers and the CFR and CFPR composites had good mechanical strength.

Porous carbon prepared by KOH chemical activation was doped with boron using B 4 C as an additive (mass fraction of 10%) by heat treatment at 850 °C for 5 h to increase its antioxidative ability. This effect is a result of a decrease in the number of active sites on the surface of the carbon after heat treatment, which inhibits its reaction with the oxidizing gas. The volume of micro and mesopores and BET surface area decreased after the doping. Although the activity of the doped porous carbon in catalytic cracking evaluated in a microreactor decreased after the doping, it still reached a higher value (70%) than that of porous carbon.