Search

Your search keyword '"Zhang, Qingfeng"' showing total 66 results
Start Over Author "Zhang, Qingfeng" Publisher wiley
66 results on '"Zhang, Qingfeng"'

2. Evaluation of left ventricular function by treadmill exercise stress echocardiography combined with layer‐specific strain technique in essential hypertension patients

Author

Zhang Qingfeng, Wang Yi, Li Wenhua, Zhang Hongmei, Ding Geqi, Liu Xuebing, Li Chunmei, Deng Yan, and Yin Lixue

Subjects
hypertension, layer‐specific strain, myocardial function, treadmill exercise stress echocardiography, Diseases of the circulatory (Cardiovascular) system, RC666-701
Abstract

Abstract The purpose of this study was to evaluate the diagnostic utility of treadmill exercise stress echocardiography (TESE) combined with left ventricular (LV) layer‐specific strain (LSS) in subclinical myocardial and reserve function of hypertensive patients. A total of 55 hypertensive patients and 51 controls were evaluated during rest and exercise. Two‐dimensional speckle tracking (2DST) and LSS technique was used to measure longitudinal and circumferential strains at rest and peak exercise, strain difference characteristics were then evaluated. Compared to the control subjects, both longitudinal and circumferential LSS showed different degrees of reduction in hypertensive group, which was more pronounced at peak exercise. The global longitudinal endocardium strain (GLSendo) at rest was 24.4% ± 1.5% in the control group versus 20.4% ± 2.3% in the hypertensive group, while the difference was more obvious at peak state (control vs. hypertensive group, 30.8% ± 2.8% and 22.8% ± 2.9%, respectively). In particular, endocardial strain under exercise can be used as a sensitive indicator where the LV contractile reserve (CR) function of the three layers are all impaired. TESE combined with LSS might increase diagnostic accuracy of myocardial performance in hypertension patients.

Published
2022
Full Text
View/download PDF

13. Assessment of left ventricular energy loss in patients with mild coronary artery stenosis by using vector flow mapping combined with exercise stress echocardiography

Author

Xiao, Qiuyu, primary, Zhao, Xin, additional, Yang, Rui, additional, Li, Zizhuo, additional, Li, Dongmei, additional, Xie, Yuanyuan, additional, Mao, Xinyue, additional, Wang, Yi, additional, Yin, Lixue, additional, Li, Chunmei, additional, Zuo, Mingliang, additional, Meng, Qingguo, additional, Li, Wenhua, additional, Liu, Xuebing, additional, Li, Zhaohuan, additional, Zhang, Qingfeng, additional, and Deng, Yan, additional

Published
2023
Full Text
View/download PDF

18. Chromosome‐level genome assembly defines female‐biased genes associated with sex determination and differentiation in the human blood fluke Schistosoma japonicum

Author

Xu, Xindong, primary, Wang, Yifeng, additional, Wang, Changhong, additional, Guo, Gangqiang, additional, Yu, Xinyu, additional, Dai, Yang, additional, Liu, Yaobao, additional, Wei, Guiying, additional, He, Xiaohui, additional, Jin, Ge, additional, Zhang, Ziqiu, additional, Guan, Qingtian, additional, Pain, Arnab, additional, Wang, Shengyue, additional, Zhang, Wenbao, additional, Young, Neil D., additional, Gasser, Robin B., additional, McManus, Donald P., additional, Cao, Jun, additional, Zhou, Qi, additional, and Zhang, Qingfeng, additional

Published
2022
Full Text
View/download PDF

19. Biomass Homogeneity Reinforced Carbon Aerogels Derived Functional Phase‐Change Materials for Solar–Thermal Energy Conversion and Storage

Author

Zhang, Qingfeng, primary, Xia, Tingfeng, additional, Zhang, Qihan, additional, Zhu, Yucao, additional, Zhang, Huanzhi, additional, Xu, Fen, additional, Sun, Lixian, additional, Wang, Xiaodong, additional, Xia, Yongpeng, additional, Lin, Xiangcheng, additional, Peng, Hongliang, additional, Huang, Pengru, additional, Zou, Yongjin, additional, Chu, Hailiang, additional, and Li, Bin, additional

Published
2022
Full Text
View/download PDF

27. Boosting Oxygen and Peroxide Reduction Reactions on PdCu Intermetallic Cubes

Author

Zhang, Qingfeng, primary, Li, Fan, additional, Lin, Lina, additional, Peng, Jiaheng, additional, Zhang, Wencong, additional, Chen, Wenlong, additional, Xiang, Qian, additional, Shi, Fenglei, additional, Shang, Wen, additional, Tao, Peng, additional, Song, Chengyi, additional, Huang, Rong, additional, Zhu, Hong, additional, Deng, Tao, additional, and Wu, Jianbo, additional

Published
2020
Full Text
View/download PDF

31. Influence of Surface Crusting on Infiltration of a Loess Plateau Soil

Author

Zhang Qingfeng, Dexter B. Watts, Wang Jian, Meng Qinqian, and Thomas R. Way

Subjects
Hydrology, Crust formation, 0208 environmental biotechnology, Soil Science, Soil science, 04 agricultural and veterinary sciences, 02 engineering and technology, Loess plateau, 020801 environmental engineering, Infiltration (hydrology), Soil crust, Loam, Soil water, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, Environmental science, Precipitation, Surface runoff
Abstract

Crusting frequently occurs on farmland soil of the Loess Plateau in China and often adversely affects agricultural yields. Therefore, a study was conducted to evaluate the occurrence of soil crusting and its influence on infiltration in a Loess Plateau silt loam soil. Simulated rainfall events were conducted at two intensities (0.67 and 1.33 mm min⁻¹) on four slopes (5, 9, 18, and 29%) under two soil conditions (crusted and uncrusted). Infiltration was evaluated as the difference between precipitation applied and water lost to runoff. A modified Green–Ampt model adjusted to account for soil crusting was also evaluated for predicting infiltration of crusted soil. Mean soil crust thickness was 3.33 and 3.94 mm under rainfall intensities of 0.67 and 1.33 mm min⁻¹, respectively. Slope had no effect on crust formation. In all instances, cumulative infiltration was lower in crusted soil than in uncrusted soil. The time to runoff decreased from 17.98 min in uncrusted soil to 4.64 min in crusted soil under a rainfall intensity of 0.67 mm min⁻¹. Time to runoff also decreased from 16.25 min in uncrusted soil to 4.54 min in crusted soil at a rainfall intensity of 1.33 mm min⁻¹. The modified Green–Ampt model provided a good estimate of soil crusting’s influence on infiltration (coefficient of determination range 0.85–0.97). This suggests that the Green–Ampt model could be used as a tool for predicting soil crusting’s influence on infiltration and runoff from soils of the Loess Plateau.

Published
2016

32. High energy density of PLZST antiferroelectric ceramics prepared by sol-gel method with low-cost dibutyltin oxide

Author

Dan, Yu, Xu, Haojie, Zhang, Yangyang, Zou, Kailun, Zhang, Qingfeng, Lu, Yinmei, Chang, Gang, Zhang, Qi, and He, Yunbin

Abstract

Lead lanthanum zirconate stannate titanate (PbLa(ZrSnTi)O3) antiferroelectric (AFE) ceramics are widely used in dielectric capacitors due to their superior energy‐storage capacity. Generally, these ceramics can be synthesized by solid‐state reaction and sol‐gel methods. Ceramics prepared using the sol‐gel method have a purer phase than those prepared using the solid‐state reaction method because the sol‐gel method can avoid the segregation of Sn. However, because the commonly used raw material tin acetate is very expensive, the preparation of PbLa(ZrSnTi)O3 AFE ceramics via the sol‐gel method is not cost‐effective, which prevents the use of sol‐gel method for manufacturing PbLa(ZrSnTi)O3 in a large scale. In this work, low‐cost dibutyltin oxide instead of expensive tin acetate is used to synthesize Pb0.97La0.02(Zr0.50Sn0.45Ti0.05)O3 (PLZST) nanopowders, and single‐phase powders with a perovskite structure and average grain size of 200 nm are obtained at a calcination temperature of 580°C. In addition, dense PLZST AFE ceramics with a pure perovskite structure are obtained by sintering the PLZST nanopowders at temperatures as low as 1100°C. The sintered PLZST ceramics exhibit a room‐temperature recoverable energy‐storage density as high as 1.93 J/cm3 with an efficiency of 75%, which varies only slightly in the temperature range of 20‐120°C. The high energy‐storage density (>1.9 J/cm3) over a wide temperature range illustrates that the sol‐gel‐derived PLZST ceramics with low‐cost dibutyltin oxide are quite promising for manufacturing pulse power capacitors.

Published
2018

Catalog

Books, media, physical & digital resources
See catalog results