Epoxy resin nanocomposites incorporated with 0.5, 1, 2, and 4 wt % pristine graphene and modified graphene oxide (GO) nanoflakes were produced and used to fabricate carbon fiber-reinforced and glass fiber-reinforced composite panels via vacuum-assisted resin transfer molding process. Mechanical and thermal properties of the composite panels-called hierarchical graphene composites-were determined according to ASTM standards. It was observed that the studied properties were improved consistently by increasing the amount of nanoinclusions. Particularly, in the presence of 4 wt % GO in the resin, tensile modulus, compressive strength, and flexural modulus of carbon fiber (glass fiber) composites were improved 15% (21%), 34% (84%), and 40% (68%), respectively. Likewise, with inclusion of 4 wt % pristine graphene in the resin, tensile modulus, compressive strength, and flexural modulus of carbon fiber (glass fiber) composites were improved 11% (7%), 30% (77%), and 34% (58%), respectively. Also, thermal conductivity of the carbon fiber (glass fiber) composites with 4% GO inclusion was improved 52% (89%). Similarly, thermal conductivity of the carbon fiber (glass fiber) composites with 4% pristine graphene inclusion was improved 45% (80%). The reported results indicate that both pristine graphene and modified GO nanoflakes are excellent options to enhance the mechanical and thermal properties of fiber-reinforced polymeric composites and to make them viable replacement materials for metallic parts in different industries, such as wind energy, aerospace, marine, and automotive.

A thin flexible coating made of pristine graphene was fabricated and applied on the surface of a commercial carbon fiber epoxy prepreg laminate to protect it against the lightning strike. To assess the coating's effectiveness, the coated laminate was subjected to the simulated lightning strike as well as the electromagnetic interference shielding effectiveness (EMI SE) testing. It was observed that the damaged area and volume in the coated laminate were reduced by 94% and 96%, respectively, as compared to the laminate without the coating. Moreover, the coated laminate had an average EMI SE of 51 dB over 100-2000 MHz range, 55 dB over 8-12 GHz range, and 60 dB over 12-18 GHz range marking 22%, 44 %, and 49% improvement in EMI SE for each frequency range, respectively. The results indicate a great potential for the developed coating to protect the commercially available prepreg composites against the lightning strike.

The transparent, detailed life cycle approach allows the data from this study to be used by radiologists to examine details of both direct and of unseen energy impacts of CT scans. The public health (outside-the-hospital) impact (including the patients receiving a CT) needs to be measured and included.

Purpose The purpose of this paper is to provide a detailed accounting of energy and materials consumed during magnetic resonance imaging (MRI). Design/methodology/approach The first and second stages of ISO standard (ISO 14040:2006 and ISO 14044:2006) were followed to develop life cycle inventory (LCI). The LCI data collection took the form of observations, time studies, real-time metered power consumption, review of imaging department scheduling records and review of technical manuals and literature. Findings The carbon footprint of the entire MRI service on a per-patient basis was measured at 22.4 kg CO2eq. The in-hospital energy use (process energy) for performing MRI is 29 kWh per patient for the MRI machine, ancillary devices and light fixtures, while the out-of-hospital energy consumption is approximately 260 percent greater than the process energy, measured at 75 kWh per patient related to fuel for generation and transmission of electricity for the hospital, plus energy to manufacture disposable, consumable and reusable products. The actual MRI and standby energy that produces the MRI images is only about 38 percent of the total life cycle energy. Research limitations/implications The focus on methods and proof-of-concept meant that only one facility and one type of imaging device technology were used to reach the conclusions. Based on the similar studies related to other imaging devices, the provided transparent data can be generalized to other healthcare facilities with few adjustments to utilization ratios, the share of the exam types, and the standby power of the facilities’ imaging devices. Practical implications The transparent detailed life cycle approach allows the data from this study to be used by healthcare administrators to explore the hidden public health impact of the radiology department and to set goals for carbon footprint reductions of healthcare organizations by focusing on alternative imaging modalities. Moreover, the presented approach in quantifying healthcare services’ environmental impact can be replicated to provide measurable data on departmental quality improvement initiatives and to be used in hospitals’ quality management systems. Originality/value No other research has been published on the life cycle assessment of MRI. The share of outside hospital indirect environmental impact of MRI services is a previously undocumented impact of the physician’s order for an internal image.

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