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Chemical analysis of polycyclic aromatic compounds in plastic materials used in indoor environmentsYara, Lania January 2023 (has links)
Human bodies are in constant interaction with materials containing known and unknown chemicals of hazardous behavior. One group of chemicals are polycyclic aromatic compounds (PACs) which can be present in both indoor and outdoor materials, commonly in plastics. PACs are known for their cancerogenic behavior and thus should be considered and studied in an attempt to decrease human exposure. The following project reports the execution and results from chemical analysis of 48 PACs including parent polycyclic aromatic hydrocarbons (PAHs), alkylated PAHs and dibenzothiophenes (S-PAC), searched for in different materials commonly found indoors. Eleven samples were prepared and analyzed using GC/MS target analysis. 23 out of the 33 parent PAHs targeted were detected and quantified. In addition, 12 out of 15 alkylated PAHs including four dibenzothiophenes (S-PAC) were detectable in the samples. The contents of parent PAHs ranged from 105 ng/g to 6700 ng/g in the samples, with the highest value being present in a laminated artificial leather sample. The alkylated PAHs ranged from 34 ng/g to 3000 ng/g, and a recycled hard plastic contained the highest amount. Amongst the parent PAHs, the dominating compound in the samples was phenanthrene. For the alkylated PAHs, 2-methylnaphtalene was the compound present in the highest mass fraction. When comparing the samples, most similarities in PAC composition could be seen in the artificial leather samples excluding a high content of naphthalene in the laminated leather. The recycled plastic material consisted of the highest variety of PACs. The results presented that none of the samples exceeded the limit values set by EU regulation regarding eight PAHs (PAH8) in consumer products. However, poor recovery in addition to poor resolution of the majority of the high molecular mass compounds suggest further investigation of method optimization.
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A Study on collaborative forecasting mechanism for artificial leather industry in TaiwanTeng, Wei-sheng 25 August 2010 (has links)
The bullwhip effect is known as a phenomenon of information distortion due to the lack of information sharing and the forecast error. This phenomenon could cause the productions plan to be instable and the inventory fluctuation among the supply chain members. Those situations above will also cause the fluctuation of purchasing costs to downstream members. The raising costs and inefficiency will be the burden of whole supply chain and not single party can exempts such result. Therefore, the collaboration of supply chain members is aim to solve such problems.
In this study, we set the manufacturer as the logistic center among supply chain members, and operate the collaborative business. The artificial leather industry in Taiwan will be the platform of this study. Operation models will be built by the classical type, CPFR type, and CCU (collaborative and coordinative unit) type, and also to be simulated to analyze the performances through several KPIs. The result of this study can be the reference when adopting CPFR or CCU into Taiwan artificial leather industry.
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