Suchergebnisse

AbstractIn the present work, we studied the NH3 and H2S odor fluxes between the exposed working area and the HDPE covering film holes of the daily overlay in an actual landfill site with a daily operating area of 1600 m2 in Hangzhou, China. We showed that the odors were released from the membrane pores and the average concentrations of NH3 and H2S release reached 109.6 ± 56.6 and 86.0 ± 31.1 mg/m2/s, respectively. These concentrations are 43.8 and 57.3 times the exposed working surface. Furthermore, mathematical modeling based on the total amount of odor release revealed that there was a linear positive correlation between the total odor amount and the landfill operation area. However, the maximum number of film holes allowed on the covering layer has nothing to do with the working area and exposed working time, which is mainly determined by the HDPE film width in terms of ensuring the deodorizing effect of the covering operation. If the HDPE film with a width of more than 4 m is used, the number of film holes allowed within 100 m is more than 8. Therefore, in order to reduce the odor, the appropriate film width should be selected according to the actual operating conditions such as the mechanical operation level at the time of welding, the design of the landfill site, and the operational norms. This study explores the effect of film hole quantity of the daily cover in the landfill on the odor release from the landfill, which can provide an important reference for the design, operation, and decision-making of the daily cover operation of the sanitary landfill.

With enactment of the universal two-child policy in China in 2016, the two-child family will replace the one-child family as the main family form. In this study we examined the contribution of sibling relationship quality in shaping the mental health of Chinese children in a two-child
family. Parents (N = 280) reported the quality of their children's sibling relationship, and their firstborn's problematic and prosocial behavior, and temperament. Parents' marital satisfaction and coparenting were also assessed. The results showed that after we had
controlled for the child characteristics of age, gender, temperament, sibling age difference, and sibling gender difference, and for the parental characteristics of age and marital satisfaction, and coparenting, sibling negativity and positivity were both significantly related to child problematic
behavior. In addition, sibling positivity was significantly related to child prosocial behavior. The results suggest that parents in a two-child family should provide guidance for their children's sibling relationship, and, in particular, increase the children's positive interaction
to improve their mental health.

Abstract Illicit drug use has become popular in China. Acknowledging the challenge of illicit drug use, China has adopted several new policies on the management of illicit drug use in recent years. This study reviews the current policies on drug use and assesses the harm reduction interventions among drug users in China. The review documents that the new policies on drug use provide a variety of choices of detoxification treatment for drug users. The methadone maintenance treatment and needle exchange programs have been adopted as harm reduction models in China. Most of the reviewed harm reduction programs have been successfully implemented and yielded positive effects in reducing drug related risk behaviors among drug users. Although there remain barriers to the effective implementation of policies on drug use and harm reduction programs, Chinese government has shown their commitment to support the expansion of harm reduction interventions for drug users throughout the country.