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921.
Wang  Tao  Zhou  Xuelin  Zou  Wenjun  Zhang  Ping  Wang  Jiaping  Li  Haotian  Wei  Shizhang  Li  Kun  Gao  Jianyi  Li  Yongzhi  Zhao  Yanling 《Journal of Thermal Analysis and Calorimetry》2018,132(3):1933-1942
Journal of Thermal Analysis and Calorimetry - The aim of the current study was to investigate the combination effect of Ginseng C. A. Mey (ginseng) and Astragalus membranaceus (Fisch.) Bunge...  相似文献   
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HIFU can pass through tissues and accurately damage target tissues inside organisms. This article reports on the oriented damage effects of HIFU upon miniswine internal and external liver tissues, and suggests a new conception of the 'biological focal field'. The results revealed that: (1) HIFU can be used to damage accurately liver tissues under the guide of a B-modal ultrasound device; (2) the scope of the injury is connected with sound intensity and irradiation time; and (3) the different layers of tissue through which the ultrasound has passed remain undamaged.  相似文献   
924.
Changes in endocardial pressure (EP) have important clinical significance for heart failure patients with impaired cardiac function. As a vital parameter for evaluating cardiac function, EP is commonly monitored by invasive and expensive cardiac catheterization, which is not feasible for long‐term and continuous data collection. In this work, a miniaturized, flexible, and self‐powered endocardial pressure sensor (SEPS) based on triboelectric nanogenerator (TENG), which is integrated with a surgical catheter for minimally invasive implantation, is reported. In a porcine model, SEPS is implanted into the left ventricle and the left atrium. The SEPS has a good response both in low‐ and high‐pressure environments. The SEPS achieves the ultrasensitivity, real‐time monitoring, and mechanical stability in vivo. An excellent linearity (R 2 = 0.997) with a sensitivity of 1.195 mV mmHg?1 is obtained. Furthermore, cardiac arrhythmias such as ventricular fibrillation and ventricular premature contraction can also be detected by SEPS. The device may promote the development of miniature implantable medical sensors for monitoring and diagnosis of cardiovascular diseases.  相似文献   
925.
Ship draft measurement is of great significance for ensuring navigation safety and facilitating ship control. In this work, a self‐powered water level sensor based on a liquid–solid tubular triboelectric nanogenerator (LST‐TENG) is proposed and analyzed. The LST‐TENG is made of multiple copper electrodes uniformly distributed along a polytetrafluoroethylene (PTFE) tube. When water flows into the PTFE tube, it induces alternating flows of electrons between the main electrode and the distributed bottom electrodes. The obvious peaks in the derivative of open‐circuit voltage with respect to time are found to correspond with the electrode distribution. Then it can be utilized as a robust and sensitive indicator for detecting the water level as the number of obvious peaks in the derivative of open‐circuit voltage is directly related to the water level height. The ship draft is successfully detected using the LST‐TENG with an accuracy of 10 mm. It shows that the water level sensor has stable performance for liquid–solid interface monitoring. Therefore, this LST‐TENG is self‐powered, robust, and accurate for extensive applications in marine industry.  相似文献   
926.
Nonstoichiometric defects, as manifested by slight deviation of elemental compositions from chemical formulas, are common yet highly important in solid materials. Oxynitrides with a relatively large O/N ratio variation are theoretically predicted to change their electronic structures and charge transport behaviors with these nonstoichiometric defects. However, little experimental effort is devoted to understanding the impact of such nonstoichiometric defects regarding varied O/N ratios in oxynitrides for solar water splitting. The main reason is the lack of suitable oxynitride research models for aforementioned nonstoichiometric defect study without interference from other factors. Using TaON as a prototypical material, finely tuned O/N ratios can dramatically influence its photoresponse. In‐depth analysis further reveals a significant impact of nonstoichiometric defects (O/N ratios) on TaON's charge carrier densities, charge separation, and transport. Finally, manipulating nonstoichiometric defects of O/N ratios demonstrates its ability to control the space charge layer width and film conductivity of TaON photoanodes for high efficiency water splitting. Therefore, a fine understanding and control of nonstoichiometric defects would be highly important for future development of high efficiency oxynitrides for water splitting.  相似文献   
927.
The self‐catalyzed growth of nanostructures on material surfaces is one of the most time‐ and cost‐effective ways to design multifunctional catalysts for a wide range of applications. Herein, the use of this technique to develop a multicomponent composite catalyst with CoSx core encapsulated in an ultrathin porous carbon shell entangled with Co, N‐codoped carbon nanotubes is reported. The as‐prepared catalyst has a superior catalytic activity for oxygen evolution and oxygen reduction reactions, an ultralow potential gap of 0.74 V, and outstanding durability, surpassing most previous reports. Such superiority is ascribed, in part, to the unique 3D electrode architecture of the composite, which is favorable for transporting oxygen species and electrons and creates a synergy between the components with different functionalities. Moreover, the flexible solid Zn–air battery assembled with such an air electrode shows a steady discharge voltage plateau of 1.25 V and a round‐trip efficiency of 70% at 1 mA cm?2. This work presents a simple strategy to design highly efficient bifunctional oxygen electrocatalysts and may pave the way for the practical application of these materials in many energy conversion/storage devices.  相似文献   
928.
Potassium‐ion batteries (PIBs) are currently drawing increased attention as a promising alternative to lithium‐ion batteries (LIBs) owing to the abundant resource and low cost of potassium. However, due to the large ionic radius size of K+, electrode material that can stably maintain K+ insertion/deintercalation is still extremely inadequate, especially for anode material with a satisfactory reversible capacity. As an attempt, nitrogen/carbon dual‐doped hierarchical NiS2 is introduced as the electrode material in PIBs for the first time. Considering that the introduction of the carbon layer effectively alleviates the volume expansion of the material itself, further improves the electronic conductivity, and finally accelerates the charge transfer of K+, not surprisingly, NiS2 decorated with the bifunctional carbon (NiS2@C@C) material electrode shows excellent potassium storage performances. When utilized as a PIB anode, it delivers a high reversible capacity of 302.7 mAh g?1 at 50 mA g?1 after 100 cycles. The first coulombic efficiency is 78.6% and rate performance is 151.2 mAh g?1 at 1.6 A g?1 of the NiS2@C@C, which are also notable. Given such remarkable electrochemical properties, this work is expected to provide more possibilities for the reasonable design of advanced electrode materials for metal sulfide potassium ion batteries.  相似文献   
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