Ce2[Zr1−x(Mg1/3Sb2/3)x]3(MoO4)9 (0.02 ⩽ x ⩽ 0.10) ceramics were prepared by the traditional solid-state method. A single phase, belonging to the space group of $$R⩈erline 3 c$$ R 3 ¯ c , was detected by using X-ray diffraction at the sintering temperatures ranging from 700 to 850 °C. The microstructures of samples were examined by applying scanning electron microscopy (SEM). The crystal structure refinement of these samples was investigated in detail by performing the Rietveld refinement method. The intrinsic properties were calculated and explored via far-infrared reflectivity spectroscopy. The correlations between the chemical bond parameters and microwave dielectric properties were calculated and analyzed by Phillips-van Vechten-Levine (P-V-L) theory. Ce2[Zr0.94(Mg1/3Sb2/3)0.06]3(MoO4)9 ceramics with excellent dielectric properties were sintered at 725 °C for 6 h (εr = 10.37, Q×f = 71,748 GHz, and τf = −13.6 ppm/°C, εr is the dielectric constant, Q×f is the quality factor, and τf is the temperature coefficient of resonant frequency).

Highly branched poly(N-isopropylacrylamide) (PNIPAM) has been synthesized by a reversible addition-fragmentation chain transfer (RAFT) copolymerization of NIPAM and a vinyl contained trithiocarbonate RAFT agent.1 H-NMR measurements revealed that the degrees of branch (DB) are in the range of 0.032-0.105. Laser light scattering (LLS) measurements gave the hydrodynamic radii (R h ) of the polymers to be 3.6-5.7 nm with molecular weight in the range of 1.3 Â 10 4 g/mol-2.3 Â 10 À4 g/mol. Highly branched PNIPAM with terminal thiol groups were obtained by aminolysis the polymers, and the product can be oxidized by air to form disulfide bonds (ASASA ) among chains and resulting in the formation of nanoparticle in aqueous solution. Interestingly, the nanoparticle in size of R h~8 0 nm showed a thermogelling behavior to form bulk hydrogel when the temperature was increased up to 25 C due to the thermo-induced association of the PNIPAM chains among the nanoparticles.

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A bacterium designated strain JB, able to degrade six benzene, toluene, ethylbenzene, and o-, m-, and p-xylene (BTEX) compounds, was isolated from petroleum-contaminated soil. Taxonomic analyses showed that the isolate belonged to Comamonas, and until now, the genus Comamonas has not included any known BTEX degraders. The BTEX biodegradation rate was slightly low on the mineral salt medium (MSM), but adding a small amount of yeast extract greatly enhanced the biodegradation. The relationship between specific degradation rate and individual BTEX was described well by Michaelis-Menten kinetics. The treatment of petrochemical wastewater containing BTEX mixture and phenol was shown to be highly efficient by BTEX-grown JB. In addition, toxicity assessment indicated the treatment of the petrochemical wastewater by BTEX-grown JB led to less toxicity than untreated wastewater.

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