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131.
132.
The capacitance of microsupercapacitors (MSCs) can double if both sides of substrates are used to construct MSCs. Nevertheless, achieving electric connections of MSCs through substrates is a challenge due to the difficulty in precisely positioning each MSC couple that has two of the same MSCs units on two sides. In this work, taking advantage of the synchronous etching on both sides of transparent polyethylene terephthalate substrates by femtosecond laser pulses, a double‐sided configuration is attained with high precision in the alignment of back‐to‐back MSC couples and versatile double‐side MSCs are realized via arbitrary on‐ and through‐substrate connections of MXene MSC units. The MXene double‐side MSC fabricated by the series connection of 12 spiral pattern MXene MSC units with interdigital electrodes of 10 μm width interspace can output a large working voltage of 7.2 V. Additionally, femtosecond laser etching brings the transformation of MXene into titania near‐etched edges with a lateral distance less than 1 µm. Such a small laser‐affected area has little influence on the capacitive performance, which is one of advantages for femtosecond laser over conventional lasers. This research is valuable for one‐step manufacturing of highly integrated MSCs in the field of miniaturized energy storage systems.  相似文献   
133.
Poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) has been is applied as hole transport material in organic electronic devices for more than 20 years. However, the redundant sulfonic acid group of PEDOT:PSS has often been overlooked. Herein, PEDOT:PSS‐DA is prepared via a facile doping of PEDOT:PSS with dopamine hydrochloride (DA·HCl) which reacts with the redundant sulfonic acid of PSS. The PEDOT:PSS‐DA film exhibits enhanced work function and conductivity compared to those of PEDOT:PSS. PEDOT:PSS‐DA‐based devices show a power conversion efficiency of 16.55% which is the highest in organic solar cells (OSCs) with (poly[(2,6‐(4,8‐bis(5‐(2‐ethylhexyl)‐4‐fluorothiophen‐2‐yl)benzo[1,2‐b:4,5‐b′]dithio‐phene))‐co‐(1,3‐di(5‐thiophene‐2‐yl)‐5,7‐bis(2‐ethylhexyl)‐benzo[1,2‐c:4,5‐c′]dithiophene‐4,8‐dione))] (PM6):(2,2′‐((2Z,2′Z)‐((12,13‐bis(2‐ethylhexyl)‐3,9‐diundecyl‐12,13‐dihydro‐[1,2,5]thiadiazolo[3,4‐e]thieno[2′′,3′:4′,5′]thieno[2′,3′:4,5]pyrrolo[3,2‐g]thieno[2′,3′:4,5]thieno[3,2‐b]indole‐2,10‐diyl)bis(methanylylidene))bis(5,6‐difluoro‐3‐oxo‐2,3‐dihydro‐1H‐indene‐2,1‐diylidene))dimalononitrile) (Y6) as the active layer. Furthermore, PEDOT:PSS‐DA also exhibits enhanced performance in three other donor/acceptor systems, exhibiting high compatibility in OSCs. This work demonstrates that doping PEDOT:PSS with various amino derivatives is a potentially efficient strategy to enhance the performance of PEDOT:PSS in organic electronic devices.  相似文献   
134.
Electrocatalysis is the most important electrode reactions for many energy storage and conversion devices, which are considered a key part of the resolution of the energy crisis. Toward this end, design of efficient electrocatalysts is of critical significance. While extensive research has been extended to develop excellent electrocatalysts, the fundamental understanding of the relationship between the electronic and structural properties of electrocatalysts and the catalytic activity must remain a priority. In this review, the activity modulation of electrocatalysts by charge transfer effects, including intramolecular and intermolecular charge transfer, is systematically introduced. With suitable charge transfer modification, such as heteroatom doping, defect engineering, molecule functionalization, and heterojunctions, the electrocatalytic activity of carbon‐based electrocatalysts can be significantly boosted. The manipulation of the electronic structure of carbon‐based materials by charge transfer may serve as a fundamental mechanism for performance enhancement. After establishing an understanding of the relationship between catalytic activity and charge transfer, the opportunities and challenges for the design of electrocatalyst with charge transfer effects are discussed.  相似文献   
135.
Covalent–organic frameworks (COFs), featuring structural diversity, framework tunability and functional versatility, have emerged as promising organic electrode materials for rechargeable batteries and garnered tremendous attention in recent years. The adjustable pore configuration, coupled with the functionalization of frameworks through pre‐ and post‐synthesis strategies, enables a precise customization of COFs, which provides a novel perspective to deepen the understanding of the fundamental problems of organic electrode materials. In this review, a summary of the recent research into COFs electrode materials for rechargeable batteries including lithium‐ion batteries, sodium‐ion batteries, potassium‐ion batteries, and aqueous zinc batteries is provided. In addition, this review will also cover the working principles, advantages and challenges, strategies to improve electrochemical performance, and applications of COFs in rechargeable batteries.  相似文献   
136.
Ionic liquids (ILs) are a family of nonconventional molten salts that offer many advantages, such as negligible vapor pressures, negligible flammability, wide liquidus ranges, good thermal stability, and much synthesis flexibility. The unique solvation environment of these ILs provides new reaction or flux media for controlling formation of solid‐state materials with a minimum perturbation of morphologies. A successful lithiation via ionothermal synthesis using a cost‐effective Li halide as Li source and recyclable ILs as solvents is reported here for the direct recycling of LiNi1/3Co1/3Mn1/3O2 (NCM 111) cathodes. In addition, the ionic liquids can be readily recycled and reused after ionothermal lithiation. The lithiation of spent cathodes can enable the direct recycling of spent cathode materials in lithium‐ion batteries.  相似文献   
137.
Ocean wave energy is a promising renewable energy source, but harvesting such irregular, “random,” and mostly ultra‐low frequency energies is rather challenging due to technological limitations. Triboelectric nanogenerators (TENGs) provide a potential efficient technology for scavenging ocean wave energy. Here, a robust swing‐structured triboelectric nanogenerator (SS‐TENG) with high energy conversion efficiency for ultra‐low frequency water wave energy harvesting is reported. The swing structure inside the cylindrical TENG greatly elongates its operation time, accompanied with multiplied output frequency. The design of the air gap and flexible dielectric brushes enable mininized frictional resistance and sustainable triboelectric charges, leading to enhanced robustness and durability. The TENG performance is controlled by external triggering conditions, with a long swing time of 88 s and a high energy conversion efficiency, as well as undiminished performance after continuous triggering for 4 00 000 cycles. Furthermore, the SS‐TENG is demonstrated to effectively harvest water wave energy. Portable electronic devices are successfully powered for self‐powered sensing and environment monitoring. Due to the excellent performance of the distinctive mechanism and structure, the SS‐TENG in this work provides a good candidate for harvesting blue energy on a large scale.  相似文献   
138.
139.
目的:探讨不同剂量舒芬太尼对心脏瓣膜置换术患者应激反应、炎性因子及心肌损伤的影响。方法:根据随机数字表法将100例行心脏瓣膜置换术的患者分为低剂量组(n=33,舒芬太尼剂量为1.0μg/kg)、中剂量组(n=33,舒芬太尼剂量为1.5μg/kg)以及高剂量组(n=34,舒芬太尼剂量为2.0μg/kg),比较三组患者应激反应、炎性因子、心肌损伤等指标的变化以及围术期指标情况。结果:中剂量组、高剂量组麻醉诱导后(T1)、插管后1 min(T2)、插管后5 min(T3)、插管后10 min(T4)时间点心率(HR)、平均动脉压(MAP)均低于低剂量组同时间点,且高剂量组低于中剂量组(P<0.05)。与低剂量组比较,中剂量组、高剂量组阻断后30 min(T6)、开主动脉后2h(T7)以及术后1d(T8)时间点白介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)均降低(P<0.05)。与低剂量组比较,中剂量组、高剂量组体外循环停机2h(T9)、体外循环停机8h(T10)、体外循环停机24h(T11)、体外循环停机48h(T12)时间点心肌肌钙蛋白I(cTnI)、肌酸磷酸激酶同工酶(CK-MB)均降低(P<0.05)。低剂量组、中剂量组重症监护室(ICU)滞留时间、拔管时间显著短于高剂量组(P<0.05),而三组心血管不良事件发生率比较差异无统计学意义(P>0.05)。结论:给予1.0μg/kg舒芬太尼麻醉的患者应激反应小,1.5μg/kg、2.0μg/kg舒芬太尼可更好地控制心脏瓣膜置换术患者炎性反应,同时对患者心肌损伤有一定的保护作用,但2.0μg/kg舒芬太尼会延长患者ICU滞留时间、拔管时间。  相似文献   
140.
目的:研究脐血管前置产前超声表现及临床效果。方法:回顾性分析2017年1月至2018年12月期间本院收治的34例脐血管前置孕妇临床资料,均进行产前超声检查,将结果与产后病理结果进行比较,分析超声表现。结果:同产后病理检查结果相比较,34例孕妇的产前超声诊断准确率、误诊率分别为97.06%、2.94%,数据对比差异无统计学意义(P>0.05),产前超声检查显示的胎盘及脐带入口情况主要为帆状胎盘、脐带胎盘边缘附着、边缘性前置胎盘、低置性前置胎盘、副胎盘等。结论:产前超声检查具有较高的脐血管前置诊断准确率,可为临床分娩结局的改善提供指导,适合推广应用在临床中。  相似文献   
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