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This paper explores the history of free zones in Ghana and Ghanaian policy makers’ related strategy. It looks at the “role of China” in these zones: both in terms of Chinese companies’ presence there, and in terms of reference to a “Chinese model” to develop free zones. On the one hand, the domestic success of special economic zones in China has validated this model and justified the creation of “Chinese SEZs” in a few African countries. On the other hand, despite a significant presence of Chinese investors and companies in Ghana - including one newly established Chinese industrial park - we find that China’s role in Ghanaian free zones is negligible. We attribute this finding, together with the absence of “Chinese SEZs” in Ghana, to a host of variables, including: Ghanaian leaders’ and policy-makers’ strategies, the country’s framework and trajectory with regard to free zones, the business environment, and some missed political opportunities.

Due to the advantages of short treatment period, no wastewater and oil produced, the CO2 laser is applied as an environment friendly thermal treatment for wood materials to improve the wood properties, such as appearance, color and wettability, etc. However, the morphological features of treated wood surface are also changed, which have negative effects on wooden product properties. To reveal the change tendency of surface roughness during laser irradiation, the common indexes of average roughness (Ra) and mean peak-to-valley height (Rz) were chosen to evaluate the surface roughness. The response surface methodology was selected to arrange the experiments and analyze the influences of laser parameters on surface roughness. The results showed that the poplar wood got rougher with the increased laser power, but the surface roughness decreased with increased feed speed and path spacing, due to the total heat absorption varied under different combination of laser parameters. The ANOVA results showed that the selected quadratic models for Ra∥, Rz∥, Ra⊥ and Rz⊥were significant due to the values of probability value (“Prob>F”) less than 0,05. In this case, all the input laser parameters were also the significant model terms for variation of surface roughness. The values of correlation coefficient were very close to 1, which meant the selected quadratic models could give accurate prediction of surface roughness for laser treated wood. Therefore, it is of great significance to predict the surface roughness of the modified wood surface scientifically and to guide the selection of reasonable modification process parameters.

Deoxynivalenol (DON) in wheat (Emai596) was degraded by five ways of ozone treatments, including ozone-gas treated wheat flour, wheat kernels before and after tempering, and tempering and washing with ozonated-water. For lab-scale milling, the effect on flour quality was investigated. The DON was quantified via high-performance liquid chromatography after extraction with immunoaffinity columns. The measure indicated all treatments could decrease the DON content of flour below 1.00 mg/kg. Ozone-gas treated wheat kernels after tempering had the highest DON degradation rate 33.33%. Ozonation produced no significant difference in gluten qualities, dynamic viscoelasticity, pasting and mixing properties, when wheat kernels were treated with ozone-gas or ozonated-water. Although ozone-gas treated flour had the highest whiteness (85.56), but it had negative effect on the rest of quality indicators. The results suggested the treatment of Ozone-gas treated tempered wheat kernels could not only degrade DON most efficiently but also ensure quality of flour.