Article
Chemistry, Physical
Yasser I. I. Abdelsalam, Firdavs A. Aliev, Renat F. Khamidullin, Aleksey V. Dengaev, Vladimir E. Katnov, Alexey V. Vakhin
Summary: In this study, catalytic thermolysis of a heavy oil sample from the Ashalcha oil field in Russia was conducted at 250 degrees C. Fullerene C60 nanoparticles were used as catalysts to promote the thermolytic reactions in the heavy oil and improve its flow behavior. The presence of water was found to contribute to the cracking of high-molecular components, resulting in a reduction of asphaltenes in the crude oil. The addition of fullerene C60 as an additive was confirmed to increase the yield of light fractions and reduce viscosity.
Article
Engineering, Chemical
Khoshim Kh. Urazov, Nikita N. Sviridenko
Summary: The study shows that the NiO precursor in heavy oil catalytic cracking can affect the composition of products, reduce the content of high molecular weight components, increase the yield of fractions, and decrease sulfur content.
JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS
(2021)
Article
Materials Science, Multidisciplinary
Terumitsu Miura, Katsuhiko Fujii, Koji Fukuya, Masahiro Kawakubo
Summary: This study irradiated carbon steels and model alloys under different radiation conditions to investigate the changes in microstructure and hardness, identifying radiation hardening factors and elucidating the effects of material composition and irradiation conditions on radiation-induced microstructure and hardness changes.
JOURNAL OF NUCLEAR MATERIALS
(2021)
Article
Energy & Fuels
Shuai Zhao, Wanfen Pu, Hao Gao, Ruofan Wang, Mikhail A. Varfolomeev, Qi Jiang, Chengdong Yuan
Summary: A thermogravimetric study was conducted to investigate the isothermal low-temperature oxidation (LTO) characteristics of heavy crude oil and its oxidized oils. The study determined the appropriate reaction orders and activation energies for the different oil samples, and found that the oils oxidized at higher temperatures had higher residual mass after thermal degradation. The developed isothermal kinetics was shown to be a useful tool for predicting the LTO behavior of heavy oils.
Article
Multidisciplinary Sciences
S. Malko, W. Cayzac, V. Ospina-Bohorquez, K. Bhutwala, M. Bailly-Grandvaux, C. McGuffey, R. Fedosejevs, X. Vaisseau, An. Tauschwitz, J. I. Apinaniz, D. De Luis Blanco, G. Gatti, M. Huault, J. A. Perez Hernandez, S. X. Hu, A. J. White, L. A. Collins, K. Nichols, P. Neumayer, G. Faussurier, J. Vorberger, G. Prestopino, C. Verona, J. J. Santos, D. Batani, F. N. Beg, L. Roso, L. Volpe
Summary: Ion stopping in warm dense matter is a process of fundamental importance but difficult to describe theoretically and measure experimentally. This study investigates proton energy-loss in warm dense plasma and finds a significant deviation from classical models. The results are in closest agreement with recent first-principles simulations based on time-dependent density functional theory.
NATURE COMMUNICATIONS
(2022)
Article
Energy & Fuels
Renbao Zhao, Tiantian Wang, Lijuan Chen, Jingjun Pan, Shutong Li, Dong Zhao, Long Chen, Jiaying Wang
Summary: The oxidation products of heavy oil during low temperature oxidation were studied through experiments, and it was found that oxygen addition and cracking reactions occur in specific temperature ranges. Components with low boiling points tend to generate high molecular weight compounds, while high boiling point components undergo cracking processes to generate lower molecular weight compounds. These findings are important for the application of low temperature oxidation in heavy oil.
Article
Chemistry, Physical
R. A. Vazirov, A. A. Narkhova, E. N. Vazirova, S. Yu Sokovnin
Summary: This investigation demonstrates the use of electron paramagnetic resonance (EPR) spectrometry for dosimetric control of wheat seeds irradiation. The study presents the general view of the wheat EPR spectra in the dose range of 0-20 kGy and analyzes the temporal kinetics of the entire spectrum and separated peaks. The intensity dependence of the EPR signal integral on the absorbed dose is obtained.
RADIATION PHYSICS AND CHEMISTRY
(2023)
Article
Energy & Fuels
Seonyong Park, Olivier Cavani, Jeremie Lefevre, Carsten Baur, Victor Khorenko, Bruno Boizot
Summary: The behavior of electron-irradiated 3G28 InGaP/GaAs/Ge triple junction solar cells and their component cells was investigated at low temperatures and low illumination intensity. Significant performance degradation was observed, with the bottom sub-cell showing higher tunneling current and degradation effects compared to the top and middle sub-cells, which were more uniform in doping profile due to epitaxial deposition. However, the degradation associated with tunneling significantly recovered in the bottom cell at 300 K.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2021)
Article
Engineering, Chemical
Ying-Jie Xu, Yun-Fei Sun, Jing-Yi Yang, Zi-Bin Huang, Pei-Qing Yuan
Summary: In this study, the dealkylation-based visbreaking of heavy oil in a hot compressed water environment was investigated. It was found that the solubilization of water reduces the viscosity of heavy oil, leading to an increase in the reaction rate of dealkylation. The hydration reaction with solubilized water suppresses condensation and extends the reaction time window for dealkylation, resulting in higher yields and lower viscosity of the products.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Green & Sustainable Science & Technology
Sara A. Alattieh, Ghazi G. Al-Khateeb, Waleed Zeiada
Summary: The study evaluated the performance of date seeds oil bio-modified asphalt binders (DSO-BMB) against fatigue and low-temperature cracking. Results showed that the bio-oil enhanced low-temperature performance and improved fatigue resistance of the modified asphalt binders.
Article
Energy & Fuels
Rajeev Kumar, Seetaram Chebrolu, Ravi Kumar Voolapalli, Sreedevi Upadhyayula
Summary: A two-stage solvent deasphalting dearomatization process was proposed for upgrading heavy oils, utilizing different solvents in each stage to improve deasphalting and dearomatization performance. By analyzing six polar solvents, the most suitable solvent for dearomatization was selected based on phase equilibria behavior, with NMP showing the highest performance index for high carbon number feedstock. The effects of solvent types and ratios on deasphalting performance were also investigated, leading to significant improvements in gasoline yields and coke reduction.
Article
Energy & Fuels
Shuai Ma, Yun-Yun Li, Ri-Gu Su, Xu-Sheng Wang, Jing-Jun Pan, Quan Shi, Guang-Zhi Liao, Chun-Ming Xu
Summary: In this study, the low-temperature oxidation (LTO) process of heavy oil was investigated by subjecting it to LTO reactions at different temperatures. The reaction products were characterized and analyzed to reveal the changes in molecular compositions and oxidation pathways. The experimental results showed that the oxidation reaction of heavy oil shifted from kinetic-controlled to diffusion-controlled as the oxidation depth increased. The oxidation reaction reached a maximum and stable value in oxygen content. The compositions of ketone compounds and acid polyoxides in the oil phase did not change significantly with further increase in reaction temperature, while the compositions of deep oxidation products in the coke phase changed significantly. The findings are important for combustion propulsion and crude oil extraction.
Article
Energy & Fuels
Yiya Wang, Riyi Lin, Liqiang Zhang, Xinlu Han, Jinyu Li, Chenxing Huang, Qiwei Dong, Pengyu Chen, Huanan Li, Xinwei Wang
Summary: This study investigates the catalytic viscosity reduction of heavy oil at low temperatures using a series of ZrO2-MoO3-based catalysts loaded on raw or modified lotus stem biochar. The results show that catalyst IV, consisting of KH570-MLSB, ZrO2, and MoO3, exhibits the best catalytic effect at 200 degrees C.
Article
Energy & Fuels
Sepideh Izaddoust, Idoia Hita, Naydu Zambrano, David Trueba, Roberto Palos, Wen Zhang, Eva Epelde, Jose M. Arandes, Pedro Castano
Summary: In this study, we investigate the conversion of heavy-fuel oil waste from marine-transport operations into transportation fuels. The process involves hydrotreatment and fluid catalytic cracking, which can reduce sulfur content and yield high-quality gasoline.
Article
Chemistry, Physical
S. Yu Sokovnin, M. E. Balezin
Summary: A surface irradiation installation based on the URT-0,5M accelerator, with built-in radiation protection and a radiation-resistant conveyor, has been developed. The tests showed that this installation can effectively disinfect eggs on both sides, with a high productivity, and provides the required level of safety with its designed protection.
RADIATION PHYSICS AND CHEMISTRY
(2022)
Article
Chemistry, Physical
A. Khallouqi, A. Halimi, O. El Rhazouani
Summary: A pediatric head phantom made of epoxy resin was used to evaluate radiation exposure in CT scans. The phantom demonstrated dosimetric properties comparable to commercially available phantoms, making it a practical and economical option for assessing radiation dose in children.
RADIATION PHYSICS AND CHEMISTRY
(2024)
Article
Chemistry, Physical
M. Y. Shoeib, Doaa A. Ahmed, A. F. Abd-Elraheem
Summary: The research aims to measure and analyze the levels of radon concentration, radium concentration, and radon exhalation rates in geopolymer cement mixes, and assess their impact on indoor air quality. Results indicate that geopolymer cement materials are safe for use in construction, except for specific mixes.
RADIATION PHYSICS AND CHEMISTRY
(2024)
Article
Chemistry, Physical
M. J. Leotlela
Summary: This article presents the results of radiochemical events/processes that occur when water is exposed to ionising radiation of charged particles (beta and alpha-particles). The idea of cogeneration becomes even more lucrative if we consider that hydrogen energy generation is clean (also known as green energy) because of its insignificant contribution to environmental pollution. These results supplement the fluctuation in effective dose theory/hypothesis of a previous study on time-dependent variations in the radiological health impact of an interim SNFS facility presented in 2021 (Leotlela, 2021).
RADIATION PHYSICS AND CHEMISTRY
(2024)
Article
Chemistry, Physical
Vyacheslav Ivanovich Pavlenko, Roman Vladimirovich Sidelnikov, Vitaly Valerievich Kashibadze, Mikhail Igorevich Dobynde, Dmitry Alexandrovich Kartashov, Vyacheslav Alexandrovich Shurshakov
Summary: This work explores the possibility of using a polymer composite to protect against neutron radiation in space conditions. The study shows that the proposed polymer composite has high structural properties necessary for use in space. Monte Carlo simulation is used to evaluate the neutron radiation passage through the material. The results demonstrate that the protective layer made of the polymer composite is thinner and more suitable for spacecraft, which is crucial due to limited space on board.
RADIATION PHYSICS AND CHEMISTRY
(2024)
Article
Chemistry, Physical
Islam G. Alhindawy, M. I. Sayyed, Dalal Abdullah Aloraini, Aljawhara H. Almuqrin, Mohammad S. Alomar, Gaber A. Elawadi, K. A. Mahmoud
Summary: This study investigated the effects of Neodymium (III) nitrate hexahydrate and lanthanum nitrate hexahydrate on the structural and radiation shielding properties of zircon mineral, and a new La/Nb-doped ZrO2 nanocomposite was fabricated. Experimental techniques such as energy-dispersive X-ray, scanning electron microscope, transmission electron microscopy, and X-ray diffraction pattern were used to analyze the structure and composition of the fabricated nanocomposites. Monte Carlo simulation was employed to evaluate the gamma-ray shielding properties. The results showed that the fabricated composites had good shielding characteristics, with a shielding capacity of 30-50% compared to pure lead in the intermediate energy range of 0.244-2.506 MeV.
RADIATION PHYSICS AND CHEMISTRY
(2024)
Article
Chemistry, Physical
Hassan Salah, Mohammed Alkhorayef, Layal Jambi, Mohammed Almuwanis, Abdelmoneim Sulieman
Summary: Cardiovascular nuclear medicine imaging examinations expose patients to high doses of ionizing radiation. This study assessed the radiation doses and public exposure in cardiac rest and stress SPECT scans. The effective dose from cardiac stress was higher than previous studies, which may be influenced by clinical indication imaging protocols and radiation safety measures.
RADIATION PHYSICS AND CHEMISTRY
(2024)
Article
Chemistry, Physical
Leandro Barbosa da Silveira Gatto, Delson Braz, Leonardo Pacifico, Paulo Travassos, Luis Alexandre Goncalves Magalhaes
Summary: This study evaluated the mean glandular dose (MGD) in mammography using a computed radiography (CR) system with a solid-state detector. Irradiations and simulations were conducted to determine the MGD and spectra for the same conditions. The results showed that the glandular dose was below the acceptable levels and the spectra were mostly in accordance with the literature.
RADIATION PHYSICS AND CHEMISTRY
(2024)
Article
Chemistry, Physical
Mawya Khafaji, Rashid Barnawi, Salma Amoudi, Hassan Gabbani, Rayan Alhazmi, Rayan Ahyad, Khalid Alsafi, Khuld Saeedi, Hassan Salah, Nissren Tamam, David Bradley, Sarah Albahiti, Abdelmoneim Sulieman
Summary: This study aimed to calculate typical values for common pediatric studies at King Abdulaziz University Hospital and compare them with other studies. The results showed that radiation dose levels in pediatric CT examinations were generally lower compared to other studies.
RADIATION PHYSICS AND CHEMISTRY
(2024)
Article
Chemistry, Physical
Faisal Almisned, Iskender Akkurt, Nurdan Karpuz
Summary: In this study, cross sections of medical radioisotopes were calculated using level density models. The results were compared with experimental data and it was found that the GSM level density models generally yielded consistent conclusions.
RADIATION PHYSICS AND CHEMISTRY
(2024)
Article
Chemistry, Physical
Shokufeh Saeid, Neda Mollakhalili-meybodi, Fateme Akrami Mohajeri, Farzan Madadizadeh, Elham Khalili Sadrabad
Summary: This study found that gamma irradiation significantly reduces the saponin and phytic acid content of quinoa. At a dose of 2.5 kGy, it can effectively reduce saponin and phytic acid without significantly damaging the antioxidant compounds.
RADIATION PHYSICS AND CHEMISTRY
(2024)
Article
Chemistry, Physical
Maria Demeter, Ion Calina, Anca Scarisoreanu, Valentina Mitran, Marcela Popa, Anisoara Cimpean, Mariana Carmen Chifiriuc, Marin Micutz, Elena Matei, Bogdana Mitu
Summary: Novel biocompatible composite hydrogels with good elastic and antimicrobial properties were synthesized by e-beam cross-linking using chitosan, water-soluble polymers, and silver nanoparticles (AgNP). The composite hydrogels showed high stability, absorption capability specific to infected wounds, and biocompatibility. The antimicrobial activity was influenced by the amount of AgNP and cross-linking degree, with significant inhibition against Gram-negative bacteria.
RADIATION PHYSICS AND CHEMISTRY
(2024)
Article
Chemistry, Physical
Anuor AT. Ayoub, Yushou Song, Mamoun IA. Sagiroun
Summary: This paper presents an assessment of the radiological hazard for humans from nuclear power plant effluent released into a river under normal operation scenarios. The study concludes that the radiological hazard from this effluent is minimal and within acceptable limits according to international standards. It also highlights the potential hazards related to the higher concentration of 137Cs in sediments over time.
RADIATION PHYSICS AND CHEMISTRY
(2024)
Article
Chemistry, Physical
Irabati Chakraborty, Nidhi Sinha, Bobby Antony
Summary: This article investigates the electron impact ionization of prebiotic molecules within the interstellar medium. By calculating the electron impact ionization cross section, the study provides insights into the chemistry of these molecules and their interaction with electrons, which play a vital role in the emergence of life's essential building blocks.
RADIATION PHYSICS AND CHEMISTRY
(2024)
Article
Chemistry, Physical
C. V. Vishnu, Antony Joseph
Summary: This study investigated the gamma-ray shielding properties of composite materials made from natural rubber with different proportions of Barium Tungstate. The addition of Barium Tungstate significantly improved the characteristics of gamma radiation shielding. The experimental measurements showed good agreement with theoretical calculations obtained from simulation results.
RADIATION PHYSICS AND CHEMISTRY
(2024)
Article
Chemistry, Physical
Derya Mutlu, Idris Karagoz, Harun Sepetcioglu, Urkiye Akar Tarim, Orhan Gurler
Summary: This study examined the properties of epoxy composites with dendritic copper particles and found that the addition of copper particles improved the electrical conductivity and mechanical properties of the composites. The glass transition temperature of the composites could be adjusted by varying the copper particle ratio. The study also evaluated the shielding properties of epoxy-based composites against gamma radiation and found that the addition of copper particles significantly altered the microstructure and mechanical properties of the composites.
RADIATION PHYSICS AND CHEMISTRY
(2024)