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891.
Hao Wang Jianmin Li Xiaoxiao Kuai Liangmin Bu Lijun Gao Xu Xiao Yury Gogotsi 《Liver Transplantation》2020,10(35)
Although 2D Ti3C2Tx is a good candidate for supercapacitors, the restacking of nanosheets hinders the ion transport significantly at high scan rates, especially under practical mass loading (>10 mg cm?2) and thickness (tens of microns). Here, Ti3C2Tx‐NbN hybrid film is designed by self‐assembling Ti3C2Tx with 2D arrays of NbN nanocrystals. Working as an interlayer spacer of Ti3C2Tx, NbN facilitates the ion penetration through its 2D porous structure; even at extremely high scan rates. The hybrid film shows a thickness‐independent rate performance (almost the same rate capabilities from 2 to 20 000 mV s?1) for 3 and 50 µm thick electrodes. Even a 109 µm thick Ti3C2Tx‐NbN electrode shows a better rate performance than 25 µm thick pure Ti3C2Tx electrodes. This method may pave a way to controlling ion transport in electrodes composed of 2D conductive materials, which have potential applications in high‐rate energy storage and beyond. 相似文献
892.
Byong‐June Lee Tong‐Hyun Kang Ha‐Young Lee Jitendra S. Samdani Yongju Jung Chunfei Zhang Zhou Yu Gui‐Liang Xu Lei Cheng Seoungwoo Byun Yong Min Lee Khalil Amine Jong‐Sung Yu 《Liver Transplantation》2020,10(22)
Despite their high theoretical energy density and low cost, lithium–sulfur batteries (LSBs) suffer from poor cycle life and low energy efficiency owing to the polysulfides shuttle and the electronic insulating nature of sulfur. Conductivity and polarity are two critical parameters for the search of optimal sulfur host materials. However, their role in immobilizing polysulfides and enhancing redox kinetics for long‐life LSBs are not fully understood. This work has conducted an evaluation on the role of polarity over conductivity by using a polar but nonconductive platelet ordered mesoporous silica (pOMS) and its replica platelet ordered mesoporous carbon (pOMC), which is conductive but nonpolar. It is found that the polar pOMS/S cathode with a sulfur mass fraction of 80 wt% demonstrates outstanding long‐term cycle stability for 2000 cycles even at a high current density of 2C. Furthermore, the pOMS/S cathode with a high sulfur loading of 6.5 mg cm?2 illustrates high areal and volumetric capacities with high capacity retention. Complementary physical and electrochemical probes clearly show that surface polarity and structure are more dominant factors for sulfur utilization efficiency and long‐life, while the conductivity can be compensated by the conductive agent involved as a required electrode material during electrode preparation. The present findings shed new light on the design principles of sulfur hosts towards long‐life and highly efficient LSBs. 相似文献
893.
The photoelectrochemical performance of the WO3 photoanode is limited by the severe charge recombination in the bulk phase and at the WO3/electrolyte interface. Herein, In2S3 nanosheets are integrated onto the surface of the WO3 nanowall array photoanode, followed by a facile polyvinylpyrrolidone (PVP) solution treatment. The PVP treatment results in sulfur vacancies and a gradient oxygen doping into In2S3 from surface to interior, which induces the formation of a gradient energy band distribution. The gradient band structured In2S3 and type II band alignment at the WO3/In2S3 interface simultaneously create a channel that favors photogenerated electrons to migrate from the surface to the conductive substrate, thereby suppressing bulk carrier recombination. Meanwhile, the sulfur vacancies and oxygen doping contribute to increased charge carrier concentration, prolonged carrier lifetime, more active sites, and small interfacial transfer impedance. As a consequence, the PVP treated WO3/In2S3 heterostructure photoanode exhibits a significantly enhanced photocurrent of 1.61 mA cm?2 at 1.23 V versus reversible hydrogen electrode (RHE) and negative onset potential of 0.02 V versus RHE. 相似文献
894.
Yinglin Xiao Bing Han Yi Zeng Shang‐Sen Chi Xianzhe Zeng Zijian Zheng Kang Xu Yonghong Deng 《Liver Transplantation》2020,10(14)
Lithium–sulfur batteries (LSBs) are considered promising candidates for the next‐generation energy‐storage systems due to their high theoretical capacity and prevalent abundance of sulfur. Their reversible operation, however, encounters challenges from both the anode, where dendritic and dead Li‐metal form, and the cathode, where polysulfides dissolve and become parasitic shuttles. Both issues arise from the imperfection of interphases between electrolyte and electrode. Herein, a new lithium salt based on an imide anion with fluorination and unsaturation in its structure is reported, whose interphasial chemistries resolve these issues simultaneously. Lithium 1, 1, 2, 2, 3, 3‐hexafluoropropane‐1, 3‐disulfonimide (LiHFDF) forms highly fluorinated interphases at both anode and cathode surfaces, which effectively suppress formation of Li‐dendrites and dissolution/shuttling of polysulfides, and significantly improves the electrochemical reversibility of LSBs. In a broader context, this new Li salt offers a new perspective for diversified beyond Li‐ion chemistries that rely on a Li‐metal anode and active cathode materials. 相似文献
895.
Wang Honghai Liu Wenjing Gao Liya Lu Yifan Chen Erxuan Xu Yuchao Liu Hongli 《Bioprocess and biosystems engineering》2020,43(4):593-604
Bioprocess and Biosystems Engineering - The reactive distillation process for the synthesis of n-butyl acetate via transesterification of ethyl acetate with n-butyl alcohol catalyzed by immobilized... 相似文献
896.
Zhan Yijing Zhu Ping Liang Jinfeng Xu Zheng Feng Xiaohai Liu Yi Xu Hong Li Sha 《Bioprocess and biosystems engineering》2020,43(1):75-84
Bioprocess and Biosystems Engineering - A safe, efficient, environmentally friendly process for producing isomaltulose is needed. Here, the biocatalyst, sucrose isomerase (SIase) from Erwinia... 相似文献
897.
目的:探讨乌司他丁联合连续性肾脏替代(CRRT)治疗对严重脓毒症患者炎症反应和血流动力学的影响。方法:选取2015年5月~2019年4月期间我院收治的严重脓毒症患者119例,将所有患者根据随机数字表法分为对照组(n=59)和研究组(n=60),对照组给予CRRT治疗,研究组在对照组基础上联合乌司他丁治疗,比较两组患者临床疗效、炎症反应指标、血流动力学参数,记录两组患者住院时间及28d内病死率。结果:研究组治疗7 d后的临床总有效率高于对照组(P0.05)。两组治疗7 d后血清白介素-6(IL-6)、降钙素原(PCT)、肿瘤坏死因子-α(TNF-α)水平均下降,且研究组低于对照组(P0.05)。两组患者治疗7 d后心率、平均动脉压(MAP)、血乳酸下降,氧合指数升高(P0.05),研究组治疗7 d后氧合指数高于对照组,血乳酸则低于对照组(P0.05)。研究组住院时间短于对照组(P0.05),两组28d内病死率比较无统计学差异(P0.05)。结论:乌司他丁联合CRRT治疗严重脓毒症患者的疗效确切,可有效抑制机体炎症反应,改善血流动力学,减少住院时间,具有一定的临床应用价值。 相似文献
898.
目的:总结一期行微通道经皮肾镜碎石术(microchannel percutaneous nephrolithotripsy,m PCNL)治疗上尿路感染性结石合并尿培养为耐碳青霉烯铜绿假单胞菌(carbapenem resistant pseudomonas aeruginosa,CRPA)的经验。方法:选择我院收治两例左肾结石合并尿培养为CRPA的患者,经积极抗感染治疗后,病例一行左侧经皮肾镜碎石术,病例二先行右肾穿刺造瘘术成功后行左侧经皮肾镜碎石术,观察分析两例患者术后结石清除情况,术中术后出现发热、腰痛、大出血、尿路损伤及肾功能衰竭等并发症情况。结果:两例患者术后复查双J管位置良好,结石基本清除;术中、术后均未出现发热、腰痛、大出血、尿路损伤及肾功能衰竭等并发症。结论:经过合适的围手术期处理,一期微通道经皮肾镜碎石术治疗感染性结石合并尿培养为耐药菌的患者是安全可行的。 相似文献
899.
900.
Luo Dan Xia Zhi Li Heng Tu Danna Wang Ting Zhang Wei Peng Lu Yi Wenfu Zhang Sai Shu Junhua Xu Hui Li Yong Shi Buyun Huang Chengjiao Tang Wen Xiao Shuna Shu Xiaolan Liu Yan Zhang Yuan Guo Shan Yu Zhi Wang Baoxiang Gao Yuan Hu Qinxue Wang Hanzhong Song Xiaohui Mei Hong Zhou Xiaoqin Zheng Zhenhua 《中国病毒学》2020,35(6):861-867
In December 2019, SARS-CoV-2 was first detected in the samples obtained from three adult patients who suffered from an unknown viral pneumonia in Wuhan (Li et al. 2020). This unknown viral pneumonia is further named as coronavirus disease 2019 (COVID-19) by the World Health Organization. To date, the number of new COVID-19 cases has continued to skyrocket and the impact of SARS-CoV-2 on humans is far greater than any pathogen of this century in both breadth and depth. Previous studies have shown that adults with COVID-19 have symptoms of fever, dry cough, dyspnea, fatigue and lymphocytopenia. Moreover, COVID-19 is more likely to cause death in the elderly, especially those with chronic comorbidities (Huang et al. 2020). In Wuhan, more than 50, 000 COVID-19 cases have been confirmed, including over 780 pediatric patients, and only one child death case (Lu et al. 2020). Although the number of children cases was far fewer than that of adults, COVID-19 might endanger children's health and the information on children remains limited, especially in serological study. In the retrospective study, the investigators analyzed the epidemiological, clinical and serological characteristics of children with COVID-19 in Wuhan in the early stages of the outbreak, which might provide theoretical and practical help in controlling COVID-19 and similar emerging infectious diseases in the future. 相似文献