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Your search keyword '"He, Kaihua"' showing total 15 results
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15 results on '"He, Kaihua"'

12. Lattice thermal conductivity of Mg2SiO4 olivine and its polymorphs under extreme conditions.

Author

Yang, Shu, Dong, Wenxin, Zhang, Li, He, Kaihua, Dai, Wei, and Lu, Chen

Abstract

The thermal transport properties of minerals at high temperature and high pressure are important for understanding the internal evolution and dynamic processes of the Earth. Here, we carry out a detailed study on the lattice thermal conductivities ( κ latt ) of Mg 2 SiO 4 under upper mantle and transition zone conditions by anharmonic lattice dynamics method. The calculations show that the κ latt of Mg 2 SiO 4 increase with the phase transitions, which agree with the previous measurements and are attributed to the increase of lifetime and group velocity under extreme conditions. The κ latt of Mg 2 SiO 4 along the geotherm shows a 64 % jump at 410 km and 71 % jump at 520 km . The anisotropy in the κ latt of olivine and wadsleyite decreases with increasing pressure. The present findings offer a fundamental knowledge of the κ latt of Mg 2 SiO 4 under extreme conditions, which are crucially important for understanding the thermal transport processes in the Earth. [ABSTRACT FROM AUTHOR]

Published
2023
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13. Effect of Thoracic Paravertebral Nerve Block on Blood Coagulation in Patients After Thoracoscopic Lobectomy: A Prospective Randomized Controlled Clinical Trial

Author

Yuan,Baohong, Liu,Danyan, Zhu,Zunyan, Hao,Yonggang, He,Kaihua, Deng,Shiyun, Yuan,Baohong, Liu,Danyan, Zhu,Zunyan, Hao,Yonggang, He,Kaihua, and Deng,Shiyun

Abstract

Baohong Yuan, Danyan Liu, Zunyan Zhu, Yonggang Hao, Kaihua He, Shiyun Deng Department of Anesthesiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of ChinaCorrespondence: Danyan Liu, Tel/Fax +86 23 8901 1069, Email liudanyan0418@163.comPurpose: Ultrasound-guided thoracic paravertebral block (TPVB) has become increasingly popular for postoperative analgesia after thoracic surgery. We designed this prospective, randomized, double-blind, placebo-controlled trial to investigate the effect of TPVB on blood coagulation in patients after thoracoscopic lobectomy.Patients and Methods: Sixty patients scheduled for thoracoscopic lobectomy were randomly allocated to two groups. Patients underwent ultrasound-guided TPVB with 0.33% ropivacaine (T group) or 0.9% saline (C group) at the end of the surgery under general anesthesia. Patient-controlled intravenous analgesia (PCIA) was administered for both group after the surgery. The primary outcome was the thromboelastogram (TEG) parameters before anesthesia (T0), at the end of operation (T1) and in 1 day (T2) and 2 days (T3) after the operation, the second outcomes were the analgesic effect and the amount of intraoperative opioid consumption, operation time, infusion volume, blood loss and urine volume.Results: The visual analog scale (VAS) scores in group T were lower than group C (P < 0.05). In group T, compared with T0, the R value at T1 and T2 is significantly reduced, and the K value at T1 were significantly shortened, the α-angle and MA value at T1 were significantly increased (P < 0.05). In group C, compared with T0, the R value and K value were significantly shortened, the α-angle and MA value were significantly increased at all postoperative time points (P < 0.05). Compared with group C at the same time point, the R and K values of group T were significantly longer, and the α-angle and MA values were significantly reduced at T2 and T3 points, with statisticall

Published
2022

15. Unexpected thermal transport properties of MgSiO 3 monolayer at extreme conditions.

Author

Zuo J, Bi J, He S, Jin W, Yu X, He K, Dai W, and Lu C

Abstract

The thermal transport properties of mantle minerals are of paramount importance to understand the thermal evolution processes of the Earth. Here, we perform extensively structural searches of two-dimensional MgSiO 3 monolayer by CALYPSO method and first-principles calculations. A stable MgSiO 3 monolayer with Pmm 2 symmetry is uncovered, which possesses a wide indirect band gap of 4.39 eV. The calculations indicate the lattice thermal conductivities of MgSiO 3 monolayer are 49.86 W (mK) -1 and 9.09 W (mK) -1 in x and y directions at room temperature. Our findings suggest that MgSiO 3 monolayer is an excellent low-dimensional thermoelectric material with high ZT value of 4.58 from n-type doping in the y direction at 2000 K. The unexpected anisotropic thermal transport of MgSiO 3 monolayer is due to the puckered crystal structure and the asymmetric phonon dispersion as well as the distinct electron states around the Fermi level. These results offer a detailed description of structural and thermal transport properties of MgSiO 3 monolayer at extreme conditions., (© 2024 IOP Publishing Ltd.)

Published
2024
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