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991.
Kuo-Kai Shyu Yu-Te Wu Tzong-Rong Chen Hui-Yun Chen Hui-Hsin Hu Wan-Yuo Guo 《Nonlinear dynamics》2010,61(3):363-372
The fetal cortical complexity is a significant quantification for assessing the development of fetal brain. This study attempts to quantify the development of fetal cortical complexity using the concept of fractal dimension (FD) analysis. Thirty-two fetal MR images were selected from Taipei Veterans General Hospital at 27–37 weeks of gestational age (GA). To investigate the FD of fetal cortical complexity, the entropy based information fractal dimension method (FD EBI), which is modified from Box-Counting method, was adopted and extended from 2D to 3D. The FD results from overall whole fetal brains show that the increase of cortical complexity is highly correlated with the gestational age of the fetus. Moreover, the FD values of right hemispheric brain are larger than those of left hemispheric brain, show that the development of right hemispheric fetal cortical complexity earlier than the left. These results are in good agreement with normal fetal brain development and suggest that the FD is an effective means for the quantification of fetal cortical complexity. 相似文献
992.
We consider a novel congestion control model, i.e., the exponential RED algorithm with a single link and single source. Using the gain parameter of the system instead of the delay as the bifurcation parameter, the linear stability and Hopf bifurcation are investigated, and the stability and direction of the Hopf bifurcation are determined by employing the normal form method and the center manifold reduction. Numerical simulations are carried out to illustrate our theoretical results. 相似文献
993.
The Stefan problem involving a source term is considered in this technical note. As an example, planar solidification with time-dependent heat generation in a semi-infinite plane is solved by use of a perturbation technique. The perturbation solution is validated by reducing the problem to the case without heat generation whose exact solution is available. An application to the case with constant heat generation is presented, for which a closed-form solution is obtained. The effects of heat generation and Stefan number on the evolution of solidification are examined using the perturbation solution. 相似文献
994.
采用K3[Fe(CN)6]作为锌镍电池的电解液添加剂,克服了锌阳极的变形。此外,通过一系列实验设计和表征,探索了电解液中金属锌与K3[Fe(CN)6]的反应机理。通过XRD (X-ray diffraction)和XPS (X-ray photo-electron spectroscopy)测试,我们发现金属锌在KOH水溶液中能够与K3[Fe(CN)6]反应,将[Fe(CN)6]3–还原为[Fe(CN)6]4−。添加K3[Fe(CN)6]的锌镍电池实现了更长的循环寿命,比不添加K3[Fe(CN)6]的锌镍电池长3倍以上。在相同循环次数下,改性电解质中锌阳极循环不仅形状变化较小,而且没有出现“死”锌现象,电极添加剂和粘结剂也没有发生偏析。此外,不同于一般的有机添加剂,K3[Fe(CN)6]的加入不仅不会增大电极的极化,还能够提高锌镍电池的放电容量和倍率性能。因此,考虑到这一改性策略有着较高的可行性和较低的成本,K3[Fe(CN)6]添加剂在锌镍电池的实际应用中具有极大的推广潜力。 相似文献
995.
Landgrave-Barbosa Fernando Marmolejo-Valencia Andrés F. Baray-Calderón Alejandro Hu Hailin Aguilar-Cordero Julio César Amador-Bedolla Carlos Ugalde-Saldivar Víctor M. 《Journal of Solid State Electrochemistry》2022,26(3):649-661
Journal of Solid State Electrochemistry - A study of poly(3-hexylthiophene) (P3HT) thin films by spin-coating process, deposited on conducting glass substrates of fluorine-doped tin oxide (FTO), is... 相似文献
996.
Hu Guanqun Huang Rui Wang Hongli Zhao Qiuping Zhang Xingkai 《Journal of Solid State Electrochemistry》2022,26(5):1313-1322
Journal of Solid State Electrochemistry - Electroless nickel-phosphorus plating is an important surface treatment method for copper due to its good corrosion resistance and nonmagnetic properties.... 相似文献
997.
Chinese Journal of Polymer Science - The emerging chemical recyclable polymers, such as poly(γ-butyrolactone) (PGBL) and poly((R)-3,4-trans six-membered ring-fused GBL) (P((R)-M)), provide a... 相似文献
998.
Changmao Wang Yaqin Wang Haitang Xie Cuijiao Zhan Xuejun He Ran Liu Rongfeng Hu Jie Shen Yuanwei Jia 《Biomedical chromatography : BMC》2022,36(3):e5287
In this work, we developed and validated a highly sensitive, rapid and stable LC–MS/MS method for the determination of ibuprofen in human plasma with ibuprofen-d3 as a stable isotopically labeled internal standard (SIL-IS). Human plasma samples were prepared by one-step protein precipitation. The chromatographic separation was achieved on a Poroshell 120 EC-C18 (2.1 × 50 mm, 2.7 μm). Aqueous solution (containing 0.05% acetic acid and 5 mm NH4Ac) and methanol were selected as the mobile phase with gradient elution. An electrospray ionization source was applied and operated in negative ion mode. Multiple reaction monitoring mode was used for quantification using target fragment ions m/z 205.0 → 161.1 for ibuprofen and m/z 208.0 → 164.0 for SIL-IS, respectively. This method exhibited a linear range of 0.05–36 μg/ml for ibuprofen with correlation coefficient >0.99. Mean recoveries of ibuprofen in human plasma ranged from 78.4 to 80.9%. The RSD of intra- and inter-day precision were both < 5%. The accuracy was between 88.2 and 103.67%. The matrix effect was negligible in human plasma, including lipidemia and hemolytic plasma. A simple, efficient and accurate LC–MS/MS method was successfully established and applied to a pharmacokinetic study in healthy Chinese volunteers after a single oral administration of ibuprofen granules. 相似文献
999.
Qimin Peng Qiuting He Yan Hu Tayirjan Taylor Isimjan Ruobing Hou Xiulin Yang 《Journal of Energy Chemistry》2022,(2):574-582
Constructing a low cost,and high-efficiency oxygen evolution reaction(OER)electrocatalyst is of great significance for improving the performance of alkaline electrolyzer,which is still suffering from highenergy consumption.Herein,we created a porous iron phosphide and tungsten oxide self-supporting electrocatalyst with oxygen-containing vacancies on foam nickel(Fe2P-WO2.92/NF)through a facile insitu growth,etching and phosphating strategies.The sequence-controllable strategy will not only generate oxygen vacancies and improve the charge transfer between Fe2P and WO2.92 components,but also improve the catalyst porosity and expose more active sites.Electrochemical studies illustrate that the Fe2P-WO2.92/NF catalyst presents good OER activity with a low overpotential of 267 mV at 100 mA cm-2,a small Tafel slope of 46.3 mV dec-1,high electrical conductivity,and reliable stability at high current density(100 mA cm-2 for over 60 h in 1.0 M KOH solution).Most significantly,the operating cell voltage of Fe2P-WO2.92/NF‖Pt/C is as low as 1.90 V at 400 mA cm-2 in alkaline condition,which is one of the lowest reported in the literature.The electrocatalytic mechanism shows that the oxygen vacancies and the synergy between Fe2P and WO2.92 can adjust the electronic structure and provide more reaction sites,thereby synergistically increasing OER activity.This work provides a feasible strategy to fabricate high-efficiency and stable non-noble metal OER electrocatalysts on the engineering interface. 相似文献
1000.
Varamesh Amir Prathapan Ragesh Telmadarreie Ali Li Jia Gourlay Keith Minhas Gurminder Lu Qingye Bryant Steven L. Hu Jinguang 《Cellulose (London, England)》2022,29(2):985-1001
Cellulose - There has been significant interest over recent years in the production and application of sustainable and green materials. Among these, nanocellulose has incurred great interest... 相似文献