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1.
Dr. Behdad Aghelnejad Prof. Geoffrey Bodenhausen Dr. Philippe Pelupessy 《Chemphyschem》2022,23(3):e202100786
Diffusion processes can be followed directly by recording one-dimensional images of a selected slice at variable intervals after selective inversion of the magnetization. The resulting diffusion coefficients of H2O and DMSO are consistent with earlier studies at different temperatures, obtained by monitoring the attenuation of NMR signals as a function of the gradient amplitude in gradient echo sequences. 相似文献
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Dariusz Marek Adam Domaski Joanna Domaska Jakub Szygua Tadeusz Czachrski Jerzy Klamka 《Entropy (Basel, Switzerland)》2021,23(5)
In this article, a way to employ the diffusion approximation to model interplay between TCP and UDP flows is presented. In order to control traffic congestion, an environment of IP routers applying AQM (Active Queue Management) algorithms has been introduced. Furthermore, the impact of the fractional controller and its parameters on the transport protocols is investigated. The controller has been elaborated in accordance with the control theory. The TCP and UDP flows are transmitted simultaneously and are mutually independent. Only the TCP is controlled by the AQM algorithm. Our diffusion model allows a single TCP or UDP flow to start or end at any time, which distinguishes it from those previously described in the literature. 相似文献
4.
Yu He Yating Guo Yanbin Yu Peifu Luo Honglong Qiu Guoming Huang 《Particle & Particle Systems Characterization》2021,38(5):2100038
In this study, manganese tellurite (MnTeO3) nanoparticles are developed as theranostic agents for magnetic resonance imaging (MRI)-guided photothermal therapy of tumor. MnTeO3 nanoparticles are synthesized via a simple one-step method. The as-synthesized MnTeO3 nanoparticles with uniform size show good biocompatibility. In particular, MnTeO3 nanoparticles exhibit a high photothermal conversion efficiency (η = 26.3%), which is higher than that of gold nanorods. Moreover, MnTeO3 nanoparticles also have high MRI performance. The longitudinal relaxivity (r1) value of MnTeO3 nanoparticles is determined to be 8.08 ± 0.2 mm −1 s−1, which is higher than that of clinically approved T1-contrast agents Gd-DTPA (4.49 ± 0.1 mm −1 s−1). The subsequent MnTeO3 nanoparticles-mediated photothermal therapy displays a highly efficient ablation of tumor cells both in vitro and in vivo with negligible toxicity. It is demonstrated that MnTeO3 nanoparticles can serve as promising theranostic agents with great potentials for MRI-guided photothermal therapy. 相似文献
5.
X-ray emission for Ar11+ ions impacting on various targets in the collisions near the Bohr velocity 下载免费PDF全文
Xian-Ming Zhou 《中国物理 B》2021,30(8):83201-083201
X-ray emission from the collisions of 3 MeV Ar11+ ions with V, Fe, Co, Ni, Cu, and Zn is investigated. Both the x-rays of the target atom and projectile are observed simultaneously. The x-ray yield is extracted from the original count. The inner-shell ionization cross section is estimated by the binary encounter approximation model and compared with the experimental result. The remarkable result is that the Ar K-shell x-ray yield is diminished with the target atomic number increasing, which is completely opposite to the theoretical calculation. That is interpreted by the competitive consumption of the energy loss for the ionization of inner-shell electrons between the projectile and target atom. 相似文献
6.
《中国物理 B》2021,30(5):56501-056501
Thermal expansion control is always an obstructive factor and challenging in high precision engineering field. Here,the negative thermal expansion of Nb F_3 and Nb OF_2 was predicted by first-principles calculation with density functional theory and the quasi-harmonic approximation(QHA). We studied the total charge density, thermal vibration, and lattice dynamic to investigate the thermal expansion mechanism. We found that the presence of O induced the relatively strong covalent bond in Nb OF_2, thus weakening the transverse vibration of F and O in Nb OF_2, compared with the case of Nb F_3.In this study, we proposed a way to tailor negative thermal expansion of metal fluorides by introducing the oxygen atoms.The present work not only predicts two NTE compounds, but also provides an insight on thermal expansion control by designing chemical bond type. 相似文献
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Chi-Kwong Li Ming-Cheng Tsai Ya-Shu Wang Ngai-Ching Wong 《Journal of Mathematical Analysis and Applications》2022,505(2):125522
Let L be an additive map between (real or complex) matrix algebras sending Hermitian idempotent matrices to Hermitian idempotent matrices. We show that there are nonnegative integers with and an unitary matrix U such that We also extend this result to the (complex) von Neumann algebra setting, and provide a supplement to the Dye-Bunce-Wright Theorem asserting that every additive map of Hermitian idempotents extends to a Jordan ?-homomorphism. 相似文献
10.
《Journal of Saudi Chemical Society》2022,26(3):101470
There would be a major effect on the cartilage regeneration characteristics of ceramic material in a substrate implant requiring biologically active biomaterials and the reinforcement phase. At this moment, we produced collagen-hyaluronic acid @ hydroxyapatite-halloysite nanotube-single walled carbon nanotube composites, which is a successful technique for making a scaffold with a superior counter for cartilage property. FTIR, XRD, and SEM-EDAX were used to perform morphological and structural studies. The prepared composite's surface feature was investigated and discovered by HRTEM-SAED analysis, and it observed porous nature. The simulated body fluids (SBF) assessment of the materials was noticed their bioactivity and chondrocytes to determine their biocompatibility. Hybrid composite displayed promise for cartilage tissue engineering despite mesenchymal stem cells compatibility effect and magnificently demonstrated an antibacterial effect without antibiotics. The live/dead cells analysis shows that the composite can significantly improve mesenchymal stem cells, and the composite has the potential ability for cartilage regeneration. The above characteristics make the material quite interesting and important in the area for regenerative medicinal uses. 相似文献