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11.
Leonid Agureev Valeriy Kostikov Svetlana Savushkina Zhanna Eremeeva Maxim Lyakhovetsky 《Materials》2022,15(17)
Materials based on the NiAl-Cr-Mo system with zirconium oxide or aluminum-magnesium spinel nanoparticle small additions were obtained by spark plasma sintering. Thermodynamic modeling was carried out to predict the phase formation in the NiAl-Cr-Mo system and its change depending on temperature, considering the presence of a small amount of carbon in the system. The phase composition and microstructure of materials were studied. NiAl (B2) and CrMo phases were found in the sintered samples. Bending strength measurements at different temperatures shows that nanoparticles of insoluble additives lead to an increase in bending strength, especially at high temperatures. A fractographic analysis of the sample’s fractures shows their hybrid nature and intercrystalline fracture, which is confirmed by the clearly visible matrix grains similar to cleavage. The maximum strength at 700 °C (475 MPa) was found for material with the addition of 0.1 wt.% zirconium oxide nanoparticles. In the study of internal friction, typical peaks of a nickel-aluminum alloy were found in the temperature ranges of 150–200 °C and 350–400 °C. 相似文献
12.
Nikolas Kirly Dominika Capkov Miroslav Almi Tom Kazda Ondej ech Pavel udek Andrea Strakov Fedorkov Maxim Lisnichuk Vera Meynen Vladimír Zelek 《RSC advances》2022,12(37):23989
Lithium–sulphur batteries attract increasing interest due to their high theoretical specific capacity, advantageous economy, and “eco-friendliness”. In this study, a metal–organic framework (MOF) GaTCPP containing a porphyrinic base ligand was used as a conductive additive for sulphur. GaTCPP was synthesized, characterized, and post-synthetically modified by the transition metal ions (Co2+/Ni2+). The doping of GaTCPP ensured an increase in the carbon dioxide adsorption capacities, which were measured under different conditions. Post-synthetic modification of GaTCPP with Co2+/Ni2+ ions has been shown to increase carbon dioxide storage capacity from 22.8 wt% for unmodified material to 23.1 wt% and 26.5 wt% at 0 °C and 1 bar for Co2+ and Ni2+-doped analogues, respectively. As a conductive part of cathode material, MOFs displayed successful sulphur capture and encapsulation proven by stable charge/discharge cycle performances, high-capacity retention, and coulombic efficiency. The electrodes with pristine GaTCPP showed a discharge capacity of 699 mA h g−1 at 0.2C in the fiftieth cycle. However, the doping of GaTCPP by Ni2+ has a positive impact on the electrochemical properties, the capacity increased to 778 mA h g−1 in the fiftieth cycle at 0.2C.Metal–porphyrin framework GaTCPP was used for carbon dioxide adsorption and as a host for preparation of a Li–S battery cathode material. 相似文献
13.
Electronic structure and magnetic properties of FeSe are calculated using the density functional approach. Due to the metallic properties, magnetic moments of the iron atoms in two nonequivalent positions in the unit cell are different from ionic values for Fe and Fe and are equal to and , making the system ferrimagnetic. The total magnetic moment for the unit cell is . Under isotropic compression, the total magnetic moment decreases non-monotonically and correlates with the non-monotonic dependence of the density of states at the Fermi level . For 7% compression, the magnetic order changes from the ferrimagnetic to the ferromagnetic. At 14% compression, the magnetic order disappears and the total magnetic moment becomes zero, leaving the system in a paramagnetic state. This compression corresponds to the pressure of 114 GPa. The magnetic ordering changes faster upon application of an isotropic external pressure due to the sizeable anisotropy of the chemical bondings in FeSe. The ferrimagnetic and paramagnetic states occur under pressures of 5.0 and 8.0 GPa, respectively. The system remains in the metallic state for all values of compression. 相似文献
14.
Angela Zagatina Nadezhda Zhuravskaya Maxim Kamenskikh Dmitry Shmatov Sergey Sayganov Fausto Rigo 《Ultrasound in medicine & biology》2018,44(7):1402-1410
There is a lack of information on the prognostic value of local high velocity in coronary arteries during echocardiography. The aim of the study described here was to define the prognostic value of local velocity >70?cm/s in the left main, anterior or circumflex artery during echocardiography. There were 412 patients in the prospective study. Death, non-fatal myocardial infarction, acute pulmonary edema, acute coronary syndrome and revascularization were defined as major adverse cardiac events (MACEs). Over 10.5?mo, there were 207 patients with MACEs. Seventeen patients died, 10 had non-fatal acute cardiac events and 184 underwent revascularization. Deaths occurred in patients with high local velocity (6.4% vs. 0%, p?<0.009). Acute cardiac events occurred in 10% versus 0% (p?<0.003). MACEs were observed in 62% versus 0% (p?<0.0000001). Only maximal velocity was an independent prognostic predictor of death (odds ratio?=?1.02, 95% confidence interval: 1.01–1.03, p?<0.02) and MACEs (odds ratio?=?1.04, 95% confidence interval: 1.02–1.05, p?<0.0001). The success rate of coronary artery visualization for at least one segment was 91%. 相似文献
15.
16.
Gabay Zarina Paltiel Gondwe Kaboni Whitney Topaz Maxim 《Maternal and child health journal》2022,26(6):1273-1273
Maternal and Child Health Journal - 相似文献
17.
Denis A. Mogilenko Oleg Shpynov Prabhakar Sairam Andhey Laura Arthur Amanda Swain Ekaterina Esaulova Simone Brioschi Irina Shchukina Martina Kerndl Monika Bambouskova Zhangting Yao Anwesha Laha Konstantin Zaitsev Samantha Burdess Susan Gillfilan Sheila A. Stewart Marco Colonna Maxim N. Artyomov 《Immunity》2021,54(1):99-115.e12
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18.
Estimating the effects of small doses of ionising radiation on DNA is one of the most important problems in modern biology. Different cytogenetic methods exist to analyse DNA damage; the cytokinesis-block micronucleus assay (CBMN) for human peripheral blood lymphocytes is a simple, cheap and informative cytogenetic method that can be used to detect genotoxic-related markers. With respect to previous studies on radiation-induced genotoxicity, children are a poorly studied group, as evidenced by the few publications in this area. In this study, we assessed radon genotoxic effects by counting micronuclei (MN), nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) in the lymphocytes of children who are long-term residents from areas with high radon concentrations. In the exposed group, radon was found to cause significant cytogenetic alterations. We propose that this method can be employed for biomonitoring to screen for a variety of measures. 相似文献
19.
Aleksey V. Larionov Maxim Y. Sinitsky Vladimir G. Druzhinin Valentin P. Volobaev Varvara I. Minina Maxim A. Asanov 《International journal of radiation biology》2016,92(8):466-474
Purpose: To study polymorphic variants of repair genes in people affected by long-term exposure to radon. The chromosome aberration frequency in peripheral blood lymphocytes was used as the biological marker of genotoxicity.Materials and methods: Genotyping of 12 single nucleotide polymorphisms in DNA repair genes (APE, XRCC1, OGG1, ADPRT, XpC, XpD, XpG, Lig4 and NBS1) was performed in children with long-term resident exposure to radon. Quantification of the aberrations was performed using light microscopy.Results: The total frequency of aberrations was increased in carriers of the G/G genotype for the XpD gene (rs13181) polymorphism in recessive model confirmed by the results of ROC-analysis (‘satisfactory predictor’, AUC?=?0.609). Single chromosome fragments frequency was increased in carriers of the G/G genotype in comparison with the T/T genotype. In respect to the total frequency of aberrations, the G/G genotype for the XpG gene (rs17655) polymorphism was also identified as a ‘satisfactory predictor’ (AUC?=?0.605). Carriers of the T/C genotype for the ADPRT gene (rs1136410) polymorphism were characterized by an increased level of single fragments relative to the T/T genotype.Conclusion: The relationships with several types of cytogenetic damage suggest these three SNP (rs13181, rs17655 and rs1136410) may be considered radiosensitivity markers. 相似文献
20.
Maxim Grymonprez Andreas Capiau Tine L. De Backer Stephane Steurbaut Koen Boussery Lies Lahousse 《Clinical cardiology》2021,44(5):599
Although obesity is associated with the development and progression of atrial fibrillation (AF), an obesity paradox may be present, illustrated by seemingly protective effects of obesity on AF‐related outcomes. Body mass index (BMI) has an impact on outcomes in AF patients using oral anticoagulants. After searching Medline and Embase, meta‐analysis of results of four randomized and five observational studies demonstrated significantly lower risks of stroke or systemic embolism (RR 0.80, 95%CI [0.73–0.87]; RR 0.63, 95%CI [0.57–0.70]; and RR 0.42, 95%CI [0.31–0.57], respectively) and all‐cause mortality (RR 0.73, 95%CI [0.64–0.83]; RR 0.61, 95%CI [0.52–0.71]; and RR 0.56, 95%CI [0.47–0.66], respectively) in overweight, obese and morbidly obese anticoagulated AF patients (BMI 25 to <30, ≥30 and ≥40 kg/m2, respectively) compared to normal BMI anticoagulated AF patients (BMI 18.5 to <25 kg/m2). In contrast, thromboembolic (RR 1.92, 95%CI [1.28–2.90]) and mortality (RR 3.57, 95%CI [2.50–5.11]) risks were significantly increased in underweight anticoagulated AF patients (BMI <18.5 kg/m2). In overweight and obese anticoagulated AF patients, the risks of major bleeding (RR 0.86, 95%CI [0.76–0.99]; and RR 0.88, 95%CI [0.79–0.98], respectively) and intracranial bleeding (RR 0.75, 95%CI [0.58–0.97]; and RR 0.57, 95%CI [0.40–0.80], respectively) were also significantly lower compared to normal BMI patients, while similar risks were observed in underweight and morbidly obese patients. This meta‐analysis demonstrated lower thromboembolic and mortality risks with increasing BMI. However, as this paradox was driven by results from randomized studies, while observational studies rendered more conflicting results, these seemingly protective effects should still be interpreted with caution. 相似文献