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Recently, resistance random access memories (RRAMs) have been studied extensively, because the demand for information storage is increasing. However, it remains challenging to obtain a flexible device because the active materials involved need to be nontoxic, nonpolluting, distortion-tolerable, and biodegradable as well adhesive to diverse flexible substrates. In this paper, tannic acid (TA) and an iron ion (FeIII ) coordination complex were employed as the active layer in a sandwich-like (Al/active layer/substrate) device to achieve memory performance. A nontoxic, biocompatible TA-FeIII coordination complex was synthesized by a one-step self-assembly solution method. The retention time of the TA-FeIII memory performance was up to 15 000 s, the yield up to 53 %. Furthermore, the TA-FeIII coordination complex can form a high-quality film and shows stable ternary memory behavior on various flexible substrates, such as polyethylene terephthalate (PET), polyimide (PI), printer paper, and leaf. The device can be degraded by immersing it in vinegar solution. Our work will broaden the application of organic coordination complexes in flexible memory devices with diverse substrates.

In this paper we explore the direct transfer via lamination of chemical vapor deposition graphene onto different flexible substrates. The transfer method investigated here is fast, simple, and does not require an intermediate transfer membrane, such as polymethylmethacrylate, which needs to be removed afterward. Various substrates of general interest in research and industry were studied in this work, including polytetrafluoroethylene filter membranes, PVC, cellulose nitrate/cellulose acetate filter membranes, polycarbonate, paraffin, polyethylene terephthalate, paper, and cloth. By comparing the properties of these substrates, two critical factors to ensure a successful transfer on bare substrates were identified: the substrate's hydrophobicity and good contact between the substrate and graphene. For substrates that do not satisfy those requirements, polymethylmethacrylate can be used as a surface modifier or glue to ensure successful transfer. Our results can be applied to facilitate current processes and open up directions for applications of chemical vapor deposition graphene on flexible substrates. A broad range of applications can be envisioned, including fabrication of graphene devices for opto/organic electronics, graphene membranes for gas/liquid separation, and ubiquitous electronics with graphene.

There is a need for Municipal Solid Waste (MSW) stream characterization and composition analysis to allow for an accurate estimation of its recycling potential and for effective management of the entire system. Recycling provides employment and a livelihood for vulnerable social groups such as refugees. The aim of this paper is to determine the composition of MSW in Zaatari Syrian Refugee Camp, where approximately 430,000 Syrian refugees have passed through the camp. The representative waste samples and analysis included household waste and commercial waste produced by the refugees in the selected districts in Zaatari. The waste sampling was performed in 2015 over two seasons to ensure that the seasonal fluctuations in the composition of the waste stream are taken into consideration. Hand sorting was used for classifying the collected wastes into the categories and subcategories. The organic waste represents the main waste category with 53% of the total MSW, while plastics, textile, and paper and cardboard are 12.85%, 10.22% and 9%, respectively. Moreover, the MSW composition percentage in Zaatari Camp is similar to that in municipalities in Jordan with slight disparity. The potential recyclable materials market has been investigated in this study. Plastics and paper and cardboard have significant potential to be separated and collected for recycling purposes. Financial revenues of potential recyclables have been analyzed based on local prices. Recycling model in the camp is also proposed based on the present study findings. Consequently, these results should be taken as a baseline for all Syrian refugees camps in the Middle East, as well as, in Europe.

The thermogravimetric and calorimetric characteristics during pyrolysis of wood, paper, textile and polyethylene terephthalate (PET) plastic in municipal solid wastes (MSW), and co-pyrolysis of biomass-derived and plastic components with and without torrefaction were investigated. The active pyrolysis of the PET plastic occurred at a much higher temperature range between 360 °C and 480 °C than 220–380 °C for the biomass derived components. The plastic pyrolyzed at a heating rate of 10 °C/min had the highest maximum weight loss rate of 18.5 wt%/min occurred at 420 °C, followed by 10.8 wt%/min at 340 °C for both paper and textile, and 9.9 wt%/min at 360 °C for wood. At the end of the active pyrolysis stage, the final mass of paper, wood, textile and PET was 28.77%, 26.78%, 21.62% and 18.31%, respectively. During pyrolysis of individual MSW components at 500 °C, the wood required the least amount of heat at 665.2 J/g, compared to 2483.2 J/g for textile, 2059.4 J/g for paper and 2256.1 J/g for PET plastic. The PET plastic had much higher activation energy of 181.86 kJ/mol, compared to 41.47 kJ/mol for wood, 50.01 kJ/mol for paper and 36.65 kJ/mol for textile during pyrolysis at a heating rate of 10 °C/min. H2O and H2 peaks were observed on the MS curves for the pyrolysis of three biomass-derived materials but there was no obvious H2O and H2 peaks on the MS curves of PET plastic. There was a significant interaction between biomass and PET plastic during co-pyrolysis if the biomass fraction was dominant. The amount of heat required for the co-pyrolysis of the biomass and plastic mixture increased with the increase of plastic mass fraction in the mixture. Torrefaction at a proper temperature and time could improve the grindability of PET plastic. The increase of torrefaction temperature and time did not affect the temperature where the maximum pyrolytic rates occurred for both biomass and plastic but decreased the maximum pyrolysis rate of biomass and increased the maximum pyrolysis rate of PET plastic. The amount of heat for the pyrolysis of biomass and PET mixture co-torrefied at 280 °C for 30 min was 4365 J/g at 500 °C, compared to 1138 J/g for the pyrolysis of raw 50% wood and 50% PET mixture at the same condition.

Stimulated by new ecology-driven European and national regulations, news routes of recycling waste appear on the market. Since food packages represent a large percentage of the plastics consumption and since they have a short lifetime, an important approach consists in making new packages from post-consumer used packages. On the other hand, food-packaging regulations in Europe require that packaging materials must be safe. Therefore, potential mass transfer (migration) of harmful recycling-related substances to the food must be excluded and test methods to ensure the safety-in-use of recycled materials for food packaging are needled. As a consequence of this situation, a European research project FAIR-CT98-4318, with the acronym 'Recyclability', was initiated. The project consists of three sections each focusing on a different class of recycled materials: polyethylene terephthalate (PET), paper and board, and plastics covered by functional barriers. The project consortium consists of 28 project members from 11 EU countries. In addition, the project is during its lifetime in discussion with the US Food and Drug Administrations (FDA) to consider also US FDA regulatory viewpoints and to aim, as a consequence, to harmonizable conclusions and recommendations. The paper introduces the project and presents an overview of the project work progress.

Background: Surgical reconstruction of congenital heart defects is often limited by the nonresorbable material used to approximate normal anatomy. In contrast, biologic scaffold materials composed of resorbable non-cross-linked extracellular matrix (ECM) have been used for tissue reconstruction of multiple organs and are replaced by host tissue. Preparation of whole organ ECM by decellularization through vascular perfusion can maintain much of the native three-dimensional (3D) structure, strength, and tissue-specific composition. A 3D cardiac ECM (C-ECM) biologic scaffold material would logically have structural and functional advantages over materials such as Dacron™ for myocardial repair, but the in vivo remodeling characteristics of C-ECM have not been investigated to date. Methods and Results: A porcine C-ECM patch or Dacron patch was used to reconstruct a full-thickness right ventricular outflow tract (RVOT) defect in a rat model with end points of structural remodeling function at 16 weeks. The Dacron patch was encapsulated by dense fibrous tissue and showed little cellular infiltration. Echocardiographic analysis showed that the right ventricle of the hearts patched with Dacron were dilated at 16 weeks compared to presurgery baseline values. The C-ECM patch remodeled into dense, cellular connective tissue with scattered small islands of cardiomyocytes. The hearts patched with C-ECM showed no difference in the size or function of the ventricles as compared to baseline values at both 4 and 16 weeks. Conclusions: The C-ECM patch was associated with better functional and histomorphological outcomes compared to the Dacron patch in this rat model of RVOT reconstruction.