Enabling Mg metal anodes rechargeable in conventional electrolytes by fast ionic transport interphase     

Ruijing Lv  Xuze Guan  Jiahua Zhang  Yongyao Xia  Jiayan Luo 《国家科学评论(英文版)》2020,7(2):333

Rechargeable magnesium batteries have received extensive attention as the Mg anodes possess twice the volumetric capacity of their lithium counterparts and are dendrite-free. However, Mg anodes suffer from surface passivation film in most glyme-based conventional electrolytes, leading to irreversible plating/stripping behavior of Mg. Here we report a facile and safe method to obtain a modified Mg metal anode with a Sn-based artificial layer via ion-exchange and alloying reactions. In the artificial coating layer, Mg₂Sn alloy composites offer a channel for fast ion transport and insulating MgCl₂/SnCl₂ bestows the necessary potential gradient to prevent deposition on the surface. Significant improved ion conductivity of the solid electrolyte interfaces and decreased overpotential of Mg symmetric cells in Mg(TFSI)₂/DME electrolyte are obtained. The coated Mg anodes can sustain a stable plating/stripping process over 4000 cycles at a high current density of 6 mA cm⁻². This finding provides an avenue to facilitate fast ion diffusion kinetics of Mg metal anodes in conventional electrolytes.  相似文献   

Exercise‐induced muscle cramp: A prospective biochemical study in marathon runners     

R.J. Maughan 《Journal of sports sciences》2013,31(1):31-34

Exercise‐induced muscle cramp has been considered to result from disturbances of fluid and electrolyte balance resulting from excessive sweat loss. Serum biochemical and haematological measurements were made on 82 male marathon runners before and after a 42.2‐km race. Fifteen (18%) of the runners reported an attack of muscle cramp which occurred after 35 ± 6 km (mean±s.d.) had been covered. These subjects were not different from the others in terms of racing performance or training status. Serum electrolyte concentrations, including sodium and potassium, were not different between those suffering from cramp and those not so affected either before or after the race, although a significant (P< 0.001) increase in serum sodium concentration occurred in both groups. Serum bicarbonate concentrations fell to the same extent (from 28 to 24 mmol 1^‐1) in both groups. Significant decreases in plasma volume, calculated from the changes in circulating haemoglobin and haemotocrit, occurred in both groups of subjects, but there was no difference in the extent of the haemoconcentration. The results suggest that exercise‐induced muscle cramp may not be associated with gross disturbances of fluid and electrolyte balance.  相似文献   

Electrochemical potential at the interface between carbon nanotubes and electrolyte     

吕建伟 《重庆大学学报(英文版)》2004,3(2):1-3

IntroductionaCarbonnanotube(CNT)isakindofcarbonallotrope,whichwasfoundin1991[1].Carbonnanotubes,particularlysingle-walledcarbonnanotubes(SWNTs),areprototypeone-dimensionalnano-materialfortheirlargeaspectratio.Theyexhibitgoodconductorandsemiconductorbehaviorsbaseontheirstructures[2].Sincetheirdiscovery,carbonnanotubeshaveattractedmuchattentionfortheirnovelstructureandmarvelousproperties.Scientistshavetakenalotofeffortstomakenano-circuitsandmolecularelectroniccomponentswithCNTs,includingfie…  相似文献   

电导法测定割手密抗寒性的研究     

丁灿 《思茅师范高等专科学校学报》2002,18(3):59-63

甘这缘野生种割手密电导率的大小与原生长地区的海拔纬度密切相关 :随原生长地点海拔的上升而下降 ;随原生长地点纬度的增高而降低 ;在相近的纬度范围内 ,决定电导率大小的因子是海拔 ;在相近的海拔范围内 ,决定电导率大小的因子是纬度 .细胞膜透性随着处理温度的下降而增加 ,它与受害组织的伤害程度呈正相关 .当膜透性处于可逆性增加时 ,反映植物细胞对寒冷的适应性变化 ;当处于半可逆性增加时 ,则是遭受冷害的标志 ;当处于不可逆性增加时 ,已是植物细胞因冷害致死的结果 .  相似文献   

Normative data for regional sweat sodium concentration and whole-body sweating rate in athletes     

Lindsay B. Baker  Kelly A. Barnes  Melissa L. Anderson  Dennis H. Passe  John R. Stofan 《Journal of sports sciences》2016,34(4):358-368

The purpose of this study was to establish normative data for regional sweat sodium concentration ([Na⁺]) and whole-body sweating rate in athletes. Data from 506 athletes (367 adults, 139 youth; 404 male, 102 female) were compiled from observational athlete testing for a retrospective analysis. The participants were skill/team-sport (including American football, baseball, basketball, soccer and tennis) and endurance (including cycling, running and triathlon) athletes exercising in cool to hot environmental conditions (15–50°C) during training or competition in the laboratory or field. A standardised regional absorbent patch technique was used to determine sweat [Na⁺] on the dorsal mid-forearm. Whole-body sweat [Na⁺] was predicted using a published regression equation (y = 0.57x+11.05). Whole-body sweating rate was calculated from pre- to post-exercise change in body mass, corrected for fluid/food intake (ad libitum) and urine output. Data are expressed as mean ± SD (range). Forearm sweat [Na⁺] and predicted whole-body sweat [Na⁺] were 43.6 ± 18.2 (12.6–104.8) mmol · L^–1 and 35.9 ± 10.4 (18.2–70.8) mmol · L^–1, respectively. Absolute and relative whole-body sweating rates were 1.21 ± 0.68 (0.26–5.73) L · h^–1 and 15.3 ± 6.8 (3.3–69.7) ml · kg^–1 · h^–1, respectively. This retrospective analysis provides normative data for athletes’ forearm and predicted whole-body sweat [Na⁺] as well as absolute and relative whole-body sweating rate across a range of sports and environmental conditions.  相似文献