BackgroundTo investigate the association between weight status and health-related quality of life (HRQOL) among pupils in Guangzhou, China.MethodsThe study comprised 5781 children aged 8–12 years from 29 schools. Height and weight were objectively measured using standardized methods, and BMI z-score derived using the age and sex specific WHO reference 2007 for 5–19 years. Weight status was classified as underweight (<−2SD), healthy weight (between -2SD and 1SD), overweight/obesity (>1SD). HRQOL was measured by the self-report version of the Pediatric Quality of Life Inventory 4.0.ResultsAfter controlling for gender, age, school type, parental education, and family income, HRQOL scores were significantly lower in overweight/obese compared with healthy weight children only in the social functioning domain (β = −1.93, p = 0.001). Compared with healthy weight children, underweight children had significantly lower total (β = −1.47, p = 0.05) and physical summary scores (β = −2.18, p = 0.02). Subgroup analysis for gender indicated that compared to healthy weight, total (β = −1.96, p = 0.02), psychosocial (β = −2.40, p = 0.01), social functioning (β = −3.36, p = 0.001), and school functioning (β = −2.19, p = 0.03) scores were lower in overweight/obese girls, but not boys. On the other hand, being underweight was associated with lower physical functioning (β = −2.27, p = 0.047) in girls, and lower social functioning (β = −3.63, p = 0.01) in boys. The associations were mainly observed in children aged 10 and over, but were not significant in younger children. Children from private schools had generally lower HRQOL compared to those in public schools, but the associations with weight status were similar in both groups.ConclusionsThe relationship between overweight/obesity and HRQOL in children in China is not as prominent as that seen in children in western or high-income countries. However, there appears to be gender and age differences, with more of an impact of overweight on HRQOL in girls and older children compared with boys and younger children. Underweight is also associated with lower HRQOL. Future intervention to prevent both obesity and undernutrition may have a positive impact on the HRQOL in children in China.

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Up to now, the member of zeolite family has expanded to more than 230. However, only little part of them have been reported as catalysts used in reactions. Discovering potential zeolites for reactions is significantly important, especially in industrial applications. A carbonylation zeolite catalyst Al-RUB-41 has special morphology and channel orientation. The 8-MR channel of Al-RUB-41 is just perpendicular to its thin sheet, making a very short mass-transfer distance along 8-MR. This specific nature endows Al-RUB-41 with efficient catalytic ability to dimethyl ether carbonylation reaction with beyond 95% methyl acetate selectivity. Compared with the most widely accepted carbonylation zeolite catalysts, Al-RUB-41 behaves a much better catalytic stability than H-MOR and a greatly enhanced catalytic activity than H-ZSM-35. A space-confined deactivation mechanism over Al-RUB-41 is proposed. By erasing the acid sites on outer surface, Al-RUB-41@SiO2 catalyst achieves a long-time and high-efficiency activity without any deactivation trend.

Reduction process is a key step to fabricate metal-zeolite catalysts in catalytic synthesis. However, because of the strong interaction force, metal oxides in zeolites are very difficult to be reduced. Existing reduction technologies are always energy-intensive, and inevitably cause the agglomeration of metallic particles in metal-zeolite catalysts or destroy zeolite structure in severe cases. Herein, we disclose that zeolites after ion exchange of ammonium have an interesting and unexpected self-reducing feature. It can accurately control the reduction of metal-zeolite catalysts, via in situ ammonia production from ‘ammonia pools’, meanwhile, restrains the growth of the size of metals. Such new and reliable ammonia pool effect is not influenced by topological structures of zeolites, and works well on reducible metals. The ammonia pool effect is ultimately attributed to an atmosphere-confined self-regulation mechanism. This methodology will significantly promote the fabrication for metal-zeolite catalysts, and further facilitate design and development of low-cost and high-activity catalysts.

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The effects of particle concentration and size on hydrodynamics and mass transport in an air–water slurry bubble column were experimentally studied. When the particle concentration αs increased from 0% to 20%, the averaged gas holdup decreased by ~30%, gas holdup of small bubbles and gas–liquid volumetric mass transfer coefficient decreased by up to 50%, while the gas holdup of large bubbles increased slightly. The overall effect of particle size was insignificant. A liquid turbulence attenuation model which could quantitatively describe the effects of particle concentration and size was first proposed. Semi‐empirical correlations were obtained based on extensive experimental data in a wide range of operating conditions and corrected liquid properties. The gas holdup and mass transfer coefficient calculated by the correlations agreed with the experimental data from both two‐phase and three‐phase bubble columns, with a maximum error <25%.

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