A Photoelectrochemical cell for direct conversion of gaseous CO2 to self-growing graphenic carbon and hydrogenated carbon

Limiting anthropogenic climate change to below 2 °C is one of the key challenges of the 21st century. Climate models suggest this cannot be achieved without drastically affecting the global economy unless carbon removal technologies, which are able to reduce absolute content of CO2 in the atmosphere, are deployed. This thesis is aimed at developing a technology to convert CO2 directly from gas phase to a solid product using non-concentrated sun light, thereby moving beyond mimicking nature’s leaf, integrating millions of years of fossilization into a real-time process. In this thesis, a novel electrolyte-less photoelectrochemical cell for direct conversion of gaseous CO2 to solid carbon using earth abundant materials is conceptualized, designed, realized, and tested. It was found that the proposed PEC is able to convert CO2 to a self-growing graphenic material, when placed in an environment where gaseous CO2, gaseous H2O, and light at natural intensity coexist. The proposed PEC was extensively experimented under different atmospheres using unassisted and assisted photoelectrochemical and electrochemical techniques. The product of CO2 conversion reaction was characterized using optical microscopy, Scanning Electron Microscopy, Energy Dispersive Spectroscopy, X-ray Photoelectron Spectroscopy, Infrared spectroscopy, Raman spectroscopy, Atomic Force Microscopy, Laser profilometry, UV-Vis spectroscopy, and Time of Flight-Secondary Mass Spectroscopy. Extensive evidences were found confirming that CO2 was converted to a mixture of graphene and hydrogenated amorphous carbon which has self-growing properties through high sp2 carbon content and semiconducting properties. Furthermore, a reaction mechanism for such a conversion on the proposed PEC was suggested. Measures to improve performance of the developed PEC were suggested and deployed were possible

A critique of the hospital services provision in Iran after implementing Health Sector Evolution Plan: A case report

Background and aims: Public sector in Iran is responsible for providing whole primary health care and approximately 85 of the second and third level services. Following the previous programs, and in order to improve health system performance, Iranian Ministry of Health and Medical Education launched Health Sector Evolution Plan of Iran (HSEP) in 2014 aimed to reduce patients’ cost, improve quality, and provide equal access for all. Methods: We examined the achievement of these objectives through reporting a case and comparing current and past situation. The data related to the case were collected by interview and surveying patient documents. Published articles were considered as a base to compare some indices before and after the plan. Results: Our case was a Ph.D. student who sought out health care for his wound treatment. Total treatment expenses were 195 and many medical supplies were used. Waiting time and visit length were calculated 345 minutes and 1 minute, respectively. Paying an amount of money equivalent to almost 57 of his salary and too long waiting time to receiving short visit are in contrast to the primary objectives of HSEP and show no improvement in these indices compared with prior to the plan. Conclusion: With regard to increasing financial resources through HSEP (70) compared with the same time before HSEP, it is necessary to manage these funds properly to achieve objectives more effective and efficient than the current ones

Optimization-Based Design and Selection of Working Fluids for Heat Transfer: Case Study in Heat Pipes

In this paper, an in silico methodology for optimizing/designing working fluids for heat transfer is presented. The method is tested for heat pipe fluids using a validated model of an evacuated tube solar water heater as a case study. Two model modes are assessed: one simplistic temperature-independent mode and one more complex temperature-dependent mode. The method demonstrates successful optimization of working fluid properties rapidly leading to optimal design of real working fluid mixtures, thus avoiding laborious and time-consuming trial-and-error experimentation. Simulations of solar water heaters with optimized working fluids lead to overall performance improvements in the order of 40%

Radiomics: The New Promise for Differentiating Progression, Recurrence, Pseudoprogression, and Radionecrosis in Glioma and Glioblastoma Multiforme

Glioma and glioblastoma multiform (GBM) remain among the most debilitating and life-threatening brain tumors. Despite advances in diagnosing approaches, patient follow-up after treatment (surgery and chemoradiation) is still challenging for differentiation between tumor progression/recurrence, pseudoprogression, and radionecrosis. Radiomics emerges as a promising tool in initial diagnosis, grading, and survival prediction in patients with glioma and can help differentiate these post-treatment scenarios. Preliminary published studies are promising about the role of radiomics in post-treatment glioma/GBM. However, this field faces significant challenges, including a lack of evidence-based solid data, scattering publication, heterogeneity of studies, and small sample sizes. The present review explores radiomics’s capabilities in following patients with glioma/GBM status post-treatment and to differentiate tumor progression, recurrence, pseudoprogression, and radionecrosis