From Aminolysis Product of PET Waste to Novel Biodegradable Polyurethanes

Chemical recycling of PET has been developed by various methods. Aminolysis is one of chemical recycling methods of PET has been developed recently. The obtained product using aminolysis, Bis (2-hydroxy ethylene) terephthalamide (BHETA), has the potential for further reactions to obtain useful products. There are few reports on usage of recycled BHETA from PET waste to synthesis of polyurethanes. On the other hand, various biodegradable polyurethanes have been synthesized using polycaprolactone diol. Therefore, caprolactone is a new potential in synthesis of biodegradable polyurethanes from PET waste. In this work, novel biodegradable polyurethanes have been synthesized using BHETA. In this order, at first polyols with different molecular weights have been synthesized through ring opening polymerization of caprolactone by BHETA, then urethane linkages were formed using HDI (Hexamethylene Diisocyanate) without chain extender. Chemical, thermal, mechanical and dynamic mechanical properties, biodegradability, morphology and UV resistance of synthesized polyurethanes have been investigated.     

Medical waste management in Jordan: a study at the King Hussein Medical Center

As in many other developing countries, the generation of regulated medical waste (RMW) in Jordan has increased significantly over the last few decades. Despite the serious impacts of RMW on humans and the environment, only minor attention has been directed to its proper handling and disposal. This study was conducted in the form of a case study at one of Jordan's leading medical centers, namely, the King Hussein Medical Center (KHMC). Its purpose was to report on the current status of medical waste management at KHMC and propose possible measures to improve it. In general, it was found that the center's administration was reasonably aware of the importance of medical waste management and practiced some of the measures to adequately handle waste generated at the center. However, it was also found that significant voids were present that need to be addressed in the future including efficient segregation, the use of coded and colored bags, better handling and transfer means, and better monitoring and tracking techniques, as well as the need for training and awareness programs for the personnel.     

Assessment of the environmental contamination with long-lived radionuclides around an operating RBMK reactor station

The presence of man-made gamma emitting radionuclides in the region within 32km radius of the Ignalina NPP/Lithuania has been investigated during the period 2001-2004, prior to the closure of the first of the two operating RBMK 1500-type reactors. Gamma spectrometric measurements of various terrestrial and aquatic plants as well as of soil samples showed moderate environmental contamination with the fission product (137)Cs and with the neutron activation products (60)Co and (54)Mn. Traces of the activation products (65)Zn and (110m)Ag were found in the nearest vicinity of the NPP. Activity concentrations were inhomogeneously distributed in the area of interest. Moss and algae samples showed the highest uptake of radionuclides. In addition to the gamma spectrometric measurements, the levels of (14)C were determined in the same bio-indicator samples using accelerator mass spectrometry.     

Risk assessment for the daily intake of polycyclic aromatic hydrocarbons from the ingestion of cockle （Anadara granosa） and exposure to contaminated water and sediments along the west coast of Peninsular Malaysia

The concentration of carcinogenic polycyclic aromatic hydrocarbons (c-PAHs) present in the sediment and water of Peninsular Malaysia as well as in the cockle Anadara granosa was investigated. Samples were extracted and analysed with gas chromatographymass spectrometry. The concentrations of total carcinogenic polycyclic aromatic hydrocarbons (t-PAHs) were measured between 0.80 0.04 to 162.96 14.74 ng/g wet weight (ww) in sediment, between 21.85 2.18 to 76.2 10.82 ng/L in water samples and between 3.34 0.77 to 46.85 5.50 ng/g ww in the cockle tissue. The risk assessment of probable human carcinogens in the Group B2 PAHs was calculated and assessed in accordance with the standards of the United States Environmental Protection Agency (US EPA). Case I in the toxicity assessment analysed the cancer risk to consumers of Malaysian blood cockle. Case II assessed the risk of cancer from exposure to PAHs from multiple pathways. The average cancer risk of case I and case II were found to be classifiable as unsafe according to the US EPA standard. The cancer risk due to c-PAHs acquired by the ingestion of blood cockle was (8.82 0.54) 10??6 to (2.67 0.06) 10??2, higher than the US EPA risk management criterion. The non-cancer risks associated with multiple pathways in Kuala Gula, Kuala Juru and Kuala Perlis were higher than the US EPA safe level, but the non-cancer risk for eating blood cockle was below the level of US EPA concern.     

Cellulose-based beads for the adsorptive removal of wastewater effluents: a review

Environmental Chemistry Letters - Wastewater pollution is a major issue requiring advanced treatment methods such as nanotechnologies. In particular, nanocelluloses appear promising as adsorbents...     

Impact of financial development and technological innovation on the volatility of green growth—evidence from China

Environmental Science and Pollution Research - China’s green growth has shown a trend of fluctuation year by year. Simultaneously, Chinese local governments have pursued simple economic...