Objective To investigate the schooling, physical health and interpersonal relationships of children affected by HIV/AIDS in rural areas of southwest China. Methods Using a structured survey, quantitative data were collected on a total of 116 children and 114 of their caregivers. Results Parental illness or death adversely affected children’s school attendance as well as school performance. Over one-third (36.2%) of children reported being ill for more than 3 days during the previous 6 months; more orphans were hospitalized during the latest illness than non-orphans although the difference was not statistically significant. One-third (33.6%) of children were aware that their parents were HIV positive. Ten percent of orphans reported their relationships with peers became worse after parental illness or death, which was significantly higher than non-orphans. Twenty-five percent of orphans reported they were teased by others compared to 1.9% of non-orphans. Conclusion HIV infection has impacted negatively on the children in terms of education, health and peer association. These findings can be used as preliminary data supporting intervention strategies and activities to improve the general welfare of children affected by HIV/AIDS in China.

The effect of ultrasound on BaSO4 nucleation is studied by measuring the induction time when nucleation is predominantly heterogeneous. In the experiments, barium sulphate is used as the working substance precipitated by mixing aqueous BaCl2 and Na2SO4 solutions with relatively low concentrations compared to the experiments of homogeneous nucleation. It is observed that at a given supersaturation level, the induction time decreases significantly with increasing ultrasonic energy during heterogeneous nucleation. In addition, the effect of ultrasound on nucleation order and the nucleation coefficient in the empirical model of nucleation rate are also investigated and compared with the corresponding effects during homogeneous nucleation.

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The effect of microwave on reactive crystallization is investigated with magnesium carbonate as the working substance. In the experiments, magnesium carbonate is precipitated by mixing aqueous magnesium sulfate and sodium carbonate solutions in a MSMPR crystallizer located in a microwave reactor. A population balance model along with crystallization kinetics is formulated to assess the influence of microwave energy input on nucleation, growth, agglomeration and breakage during crystallization process. A general high order moment method of classes (HMMC) framework is applied to solve the model numerically. The results show that crystallization kinetics parameters, including the nucleation rate constant (kn), the growth rate constant (kg), the exponent of growth rate (g) and the collision efficiency (Ψag) change significantly due to mass transfer enhancement in microwave field. Meanwhile, the exponent of nucleation (n) and the breakage rate constant (kbr) remain constant or only change slightly. It is further discovered that the crystal suspension attenuates the microwave effect during crystallization process.