Implementing the 3E assessment model of sustainable development to investigate coastal pollution management: using PET recycling (bottle-to-fiber) as a case study

Recently, plastic pollution of the ocean has been garnering increasing attention. The United Nations considers the problem as a major issue, and the UN Environment Programme (UNEP) has launched a global "Clean Ocean" campaign. An estimated 51 trillion plastic particles can be found in our oceans, and the pollution has caused plastics to enter the food chain. This study investigates the life cycle of recycling waste PET (polyethylene terephthalate) bottles in the ocean to the regeneration of recycled raw materials in the process of producing blankets made from such materials. First, the activity data of the relevant literature was collected, and the life cycle assessment software Open LCA was used as the assessment tool. We assume that the functional unit is 1 kg of recycled PET bottles. Secondly, with the ILCD 2011 Midpoint impact assessment method for environmental impact analysis, we identify the impact of pollutants generated during the recycling process on the environment as follows: Photochemical ozone formation 7872256.41218/ kg NMVOC eq; Fresh-water ecotoxicity 240566129.10051/ CTUe; Human toxicity, cancer effects 120.28305/ CTUh; Human toxicity, non-cancer effects 1.53496/ CTUh. Finally, we conduct risk assessment using the 3E (Engineering, Environment and Economic) assessment model, and propose an overall recovery treatment optimization assessment model

A Comparative Study on Spin-Orbit Torque Efficiencies from W/ferromagnetic and W/ferrimagnetic Heterostructures

It has been shown that W in its resistive form possesses the largest spin-Hall ratio among all heavy transition metals, which makes it a good candidate for generating efficient dampinglike spin-orbit torque (DL-SOT) acting upon adjacent ferromagnetic or ferrimagnetic (FM) layer. Here we provide a systematic study on the spin transport properties of W/FM magnetic heterostructures with the FM layer being ferromagnetic Co$_{20}$Fe$_{60}$B$_{20}$ or ferrimagnetic Co$_{63}$Tb$_{37}$ with perpendicular magnetic anisotropy. The DL-SOT efficiency $|\xi_{DL}|$, which is characterized by a current-induced hysteresis loop shift method, is found to be correlated to the microstructure of W buffer layer in both W/Co$_{20}$Fe$_{60}$B$_{20}$ and W/Co$_{63}$Tb$_{37}$ systems. Maximum values of $|\xi_{DL}|\approx 0.144$ and $|\xi_{DL}|\approx 0.116$ are achieved when the W layer is partially amorphous in the W/Co$_{20}$Fe$_{60}$B$_{20}$ and W/Co$_{63}$Tb$_{37}$ heterostructures, respectively. Our results suggest that the spin Hall effect from resistive phase of W can be utilized to effectively control both ferromagnetic and ferrimagnetic layers through a DL-SOT mechanism

Interaction induced ferro-electricity in the rotational states of polar molecules

We show that a ferro-electric quantum phase transition can be driven by the dipolar interaction of polar molecules in the presence a micro-wave field. The obtained ferro-electricity crucially depends on the harmonic confinement potential, and the resulting dipole moment persists even when the external field is turned off adiabatically. The transition is shown to be second order for fermions and for bosons of a smaller permanent dipole moment, but is first order for bosons of a larger moment. Our results suggest the possibility of manipulating the microscopic rotational state of polar molecules by tuning the trap's aspect ratio (and other mesoscopic parameters), even though the later's energy scale is smaller than the former's by six orders of magnitude.Comment: 4 pages and 4 figure