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91.
Oxygen Vacancies Evoked Blue TiO2(B) Nanobelts with Efficiency Enhancement in Sodium Storage Behaviors 下载免费PDF全文
Yan Zhang Zhiying Ding Christopher W. Foster Craig E. Banks Xiaoqing Qiu Xiaobo Ji 《Advanced functional materials》2017,27(27)
Oxygen vacancies (OVs) dominate the physical and chemical properties of metal oxides, which play crucial roles in the various fields of applications. Density functional theory calculations show the introduction of OVs in TiO2(B) gives rise to better electrical conductivity and lower energy barrier of sodiation. Here, OVs evoked blue TiO2(B) (termed as B‐TiO2(B)) nanobelts are successfully designed upon the basis of electronically coupled conductive polymers to TiO2, which is confirmed by electron paramagnetic resonance and X‐ray photoelectron spectroscopy. The superiorities of OVs with the aid of carbon encapsulation lead to higher capacity (210.5 mAh g?1 (B‐TiO2(B)) vs 102.7 mAh g?1 (W‐TiO2(B)) at 0.5 C) and remarkable long‐term cyclability (the retention of 94.4% at a high rate of 10 C after 5000 times). In situ X‐ray diffractometer analysis spectra also confirm that an enlarged interlayer spacing stimulated by OVs is beneficial to accommodate insertion and removal of sodium ions to accelerate storage kinetics and preserve its original crystal structure. The work highlights that injecting OVs into metal oxides along with carbon coating is an effective strategy for improving capacity and cyclability performances in other metal oxide based electrochemical energy systems. 相似文献
92.
Field‐Induced n‐Doping of Black Phosphorus for CMOS Compatible 2D Logic Electronics with High Electron Mobility 下载免费PDF全文
Yijun Xu Jian Yuan Kai Zhang Yuan Hou Qiu Sun Yingming Yao Shaojuan Li Qiaoliang Bao Han Zhang Yuegang Zhang 《Advanced functional materials》2017,27(38)
Black phosphorus (BP) has been considered as a promising two‐dimensional (2D) semiconductor beyond graphene owning to its tunable direct bandgap and high carrier mobility. However, the hole‐transport‐dominated characteristic limits the application of BP in versatile electronics. Here, we report a stable and complementary metal oxide semiconductor (COMS) compatible electron doping method for BP, which is realized with the strong field‐induced effect from the K+ center of the silicon nitride (SixNy). An obvious change from pristine p‐type BP to n type is observed after the deposit of the SixNy on the BP surface. This electron doping can be kept stable for over 1 month and capable of improving the electron mobility of BP towards as high as ~176 cm2 V–1 s–1. Moreover, high‐performance in‐plane BP p‐n diode and further logic inverter were realized by utilizing the n‐doping approach. The BP p‐n diode exhibits a high rectifying ratio of ~104. And, a successful transfer of the output voltage from “High” to “Low” with very few voltage loss at various working frequencies were also demonstrated with the constructed BP inverter. Our findings paves the way for the success of COMS compatible technique for BP‐based nanoelectronics. 相似文献
93.
为满足低等级红外探测器组件在高可靠性领域的空间应用需求,对星载红外探测器组件进行温度循环试验、力学试验以及高温老炼试验等环境试验考核,并基于双积分球式均匀照明系统对环境试验前后红外探测器组件相对光谱响应率进行测试。通过对比环境试验前后红外探测器组件相对光谱响应率变化,分析红外探测器组件的环境适应性,揭示红外探测器组件的质量缺陷及其他潜在缺陷,剔除早期失效,并从参试红外探测器组件中筛选出性能优良的探测器应用在星载偏振扫面仪进行大气偏振探测。试验结果表明:参试的红外探测器组件在环境试验前后具有良好的稳定性和可靠性,可以满足航天载荷应用需求。 相似文献
94.
95.
研究了有机交叉点存储器件中,有机物与电极界面化学反应形成的纳米颗粒对电学特征的影响.器件的阳极和阴极分别为氧化铟锡(ITO)导电玻璃和真空热蒸发沉积的~薄膜,有机半导体层为真空热蒸发沉积的2-amino-4,5-dicyanoimidazole(AlDcN)薄膜.通过透射电子显微镜(TEM)和X光电子能谱(XPS)测量,在AIDCN/ITO界面上发现SnOx纳米颗粒形成,并证明此纳米颗粒的形成是由于ITO中的高价氧化锡和AIDCN之间的固相反应,纳米颗粒中的Sn元素主要是从ITO表面的锡富集层中析出.研究证明了界面上纳米颗粒的形成是器件双稳态现象的关键,用这种方式制成的交叉点结构的三层有机存储器件其开关比达到107~1011. 相似文献
96.
摘 要:目的 观察聪脑益智针法联合精神运动康复改善脑瘫患儿认知功能障碍的临床疗效。方法 选取我院住院脑瘫患儿伴有认知功能障碍者100例为研究对象,以随机数字表法分为综合康复组、聪脑益智针法联合精神运动康复训练组各50例。两组患儿均以综合康复治疗为基础,治疗组在综合康复治疗基础上进行聪脑益智针刺联合精神运动康复训练治疗,两组患儿均治疗3个月,治疗前后均按参照有关文献拟定的疗效标准进行评定观察。结果 应用聪脑益智针法联合精神运动康复训练治疗脑瘫患儿认知功能障碍在提高智力方面亦优于常规综合治疗组,差异有统计学意义(P<0.05)。结论 聪脑益智针法联合精神运动康复可有效改善脑瘫患儿认知障碍,临床疗效明显,值得在临床上推广应用。 相似文献
97.
为了满足光纤通信系统中对线路编码的特殊要求,在深入分析现有8B/10B编码原理的基础上,提出了一种新的将同步块分组法与查找表法相结合的8B/10B编码方案。此方案的优势在于能在同一时钟下同步完成3B/4B编码和5B/6B编码,进而通过Disparity和Running Disparity这两个参数来控制编码后的4 bit数据和6 bit数据,使之结合为10 bit并行数据,最后通过串化器转化为高速的串行数据进行输出。整体设计方案用VHDL硬件语言实现了算法的描述,并在QuartusⅡ软件平台上实现了整个编码器的电路综合和波形仿真,结果表明该方案具有占用资源少、编码速度快、实时性好、可靠性高等优点,并且充分满足光纤通信中对高速数据传输的要求。 相似文献
98.
Wanwan Qiu Jenny Gehlen Margherita Bernero Christian Gehre Gian Nutal Schädli Ralph Müller Xiao-Hua Qin 《Advanced functional materials》2023,33(20):2214393
Tomographic volumetric bioprinting (VBP) enables fast photofabrication of cell-laden hydrogel constructs in one step, addressing the limitations of conventional layer-by-layer additive manufacturing. However, existing biomaterials that fulfill the physicochemical requirements of VBP are limited to gelatin-based photoresins of high polymer concentrations. The printed microenvironments are predominantly static and stiff, lacking sufficient capacity to support 3D cell growth. Here a dynamic resin based on thiol–ene photo-clickable polyvinyl alcohol (PVA) and thermo-sensitive sacrificial gelatin for fast VBP of functional ultrasoft cell-laden hydrogel constructs within 7–15 s is reported. Using gelatin allows VBP of permissive hydrogels with low PVA contents of 1.5%, providing a stress-relaxing environment for fast cell spreading, 3D osteogenic differentiation of embedded human mesenchymal stem cells and matrix mineralization. Additionally, site-specific immobilization of molecules-of-interest inside a PVA hydrogel is achieved by 3D tomographic thiol–ene photopatterning. This technique may enable spatiotemporal control of cell-material interactions and guides in vitro tissue formation using programmed cell-friendly light. Altogether, this study introduces a synthetic dynamic photoresin enabling fast VBP of functional ultrasoft hydrogel constructs with well-defined physicochemical properties and high efficiency. 相似文献
99.
针对用户、服务提供商(SP)和基础设施提供商三者之间的市场行为所带来的收益问题,该文面向服务提供商提出了一种两阶段多虚拟机资源分配机制。首先,建立能力规划模型并引入粒子群算法,决策出服务提供商收益最大化的资源购买方案。然后,提出一种优化用户满意度的服务提供策略,优化了服务提供商的长期收益。最后仿真实验结果表明,该方法有效提高了服务提供商的收益,并取得了较好的用户满意度。 相似文献
100.
As the computer network increasingly grows larger and more complex, fault diagnosis has become a challenging task. Active probing is an efficient tool for fault localization. By implementing some test programs and analyzing the results, active‐probing‐based techniques can perform diagnosis efficiently and adaptively. Because probes may generate additional traffic overhead, it is important to appropriately select small number of probes to reach the desired diagnostic capability. However, the computation of probe selection problem in such environment is extremely expensive. Most of the past works purchase the speed at the cost of diagnostic accuracy. In this paper, we first verify that probe selection problem satisfies the property of submodularity. Then we take the use of the property and develop a submodularity‐based selection algorithm with following novel features: (i) it is cost effective, failure resistant and more accurate; (ii) it could deal with the uncertainties about the network structures and the observations; and (iii) it can select the required probes in near‐linear time. Finally, we implement submodularity‐based selection algorithm and other two representative probe selection algorithms (bounded path enumeration approximation algorithm and greedy search algorithm) on different settings of networks. The results have shown how the new algorithm outperforms the former two algorithms. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献