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991.
Kai Lin Zhao Ma Jin Li Menghuan Tang Aaron Lindstrom Mythili Ramachandran Shaoming Zhu Tzu-yin Lin Lanwei Zhang Yuanpei Li 《Advanced functional materials》2021,31(10):2008460
Photodynamic therapy (PDT) has emerged as an attractive alternative in cancer therapy, but its therapeutic effects are limited by the nonselective subcellular localization and poor intratumoral retention of small-molecule photosensitizes. Here a fiber-forming nanophotosensitizer (PQC NF) that is composed of mitochondria targeting small molecules of amphiphilicity is reported. Harnessing the specific mitochondria targeting, the light-activated PQC NFs produce approximately 110-fold higher amount of reactive oxygen species in cells than free photosensitizers and can dramatically induce mitochondrial disruption to trigger intense apoptosis, showing 20–50 times better in vitro anticancer potency than traditional photosensitizers. As fiber-shaped nanomaterials, PQC NFs also demonstrated a long-term retention in tumor sites, solving the challenge of rapid clearance of small-molecule photosensitizers from tumors. With these advantages, PQC NFs achieve a 100% complete cure rate in both subcutaneous and orthotopic oral cancer models with the administration of only a single dose. This type of single small molecule-assembled mitochondria targeting nanofibers offers an advantageous strategy to improve the in vivo therapeutic effects of conventional PDT. 相似文献
992.
Jiaming Huang Zhiwei Ren Yaokang Zhang Kuan Liu Hengkai Zhang Hua Tang Cenqi Yan Zijian Zheng Gang Li 《Advanced functional materials》2021,31(16):2010172
Flexible photovoltaic devices are promising candidates for triggering the Internet of Things (IoT). However, the power conversion efficiencies (PCEs) of flexible organic photovoltaic (OPV) devices with high conductivity poly(3,4-ethylene dioxythiophene):polystyrene sulfonate (PEDOT:PSS) electrodes on plastic are lagging behind the rigid devices due to the low transmittance of polyethylene terephthalate (PET)/PEDOT:PSS. Moreover, the poor stretchability of the commonly used plastic substrates largely hinders the practical application of wearable devices. Herein, a novel stretchable indium tin oxide (ITO)-free OPV device with a surface-texturing polydimethylsiloxane (PDMS) substrate for outdoor strong- and indoor dim-light energy harvesting is reported. The high diffuse transmittance and haze effect of the substrate enable stretchable ITO-free devices, yielding a high PCE of 15.3% under 1 sun illumination. More excitingly, the stretchable device based on textured PDMS/PEDOT:PSS maintains a comparable PCE of 20.5% (20.8% for the rigid device) under indoor light illumination. Notably, the stretchable device is much more insensitive to the light direction, maintaining 38.5% of the initial PCE at an extremely small incident angle of 10° (16.3% for glass/ITO-based counterpart). The texturing stretchable substrate provides a new direction for achieving high performance and enhanced light utilization for the stretchable light-harvesting device, suitable for indoor and outdoor applications. 相似文献
993.
Public adoption of policies detailed on government websites is an important topic in the field of e-government research, and researchers have mainly focused on the key factors that influence initial adoption. However, there has been much less discussion on factors influencing the continued use of government websites. This study identifies and tests a theoretical model that predicts consumers’ intentions to continue using government portals, using a mixed methods approach based on Grounded Theory. To construct a theoretical framework of public interest in continued use of government information portals, we interviewed 56 respondents and coded the interview data. Next, we tested the resulting model using data collected from a questionnaire-based survey of 354 users. The Structural Equation Modeling (SEM) results indicate that continued use is influenced by psychological perception, user characteristics, service parameters of the government portals and the government’s idea. Of these, psychological perception was found to have the strongest effect. These findings enrich the theoretical system of e-government public adoption of intention and have important practical significance for the development of Chinese government portals. 相似文献
994.
Mingbo Zheng Hao Tang Qin Hu Shasha Zheng Lulu Li Jing Xu Huan Pang 《Advanced functional materials》2018,28(20)
Lithium‐ion batteries are widely used as reliable electrochemical energy storage devices due to their high energy density and excellent cycling performance. The search for anode materials with excellent electrochemical performances remains critical to the further development of lithium‐ion batteries. Tungsten‐based materials are receiving considerable attention as promising anode materials for lithium‐ion batteries owing to their high intrinsic density and rich framework diversity. This review describes the advances of exploratory research on tungsten‐based materials (tungsten oxide, tungsten sulfide, tungsten diselenide, and their composites) in lithium‐ion batteries, including synthesis methods, microstructures, and electrochemical performance. Some personal prospects for the further development of this field are also proposed. 相似文献
995.
Pingfan Chen Zhen Huang Changjian Li Bangmin Zhang Nina Bao Ping Yang Xiaojiang Yu Shengwei Zeng Chunhua Tang Xiaohan Wu Jingsheng Chen Jun Ding Stephen John Pennycook A. Ariando Thirumalai Venky Venkatesan Gan Moog Chow 《Advanced functional materials》2018,28(33)
The complex interfacial correlations provide new routes toward tunable functionalities. Here, the wide range of tunabilities for magnetic properties are presented, including Curie temperature (from 245 to 320 K), coercive field (from 2 to 205 Oe), and saturated magnetic moment (from 0.9 to 2.8 µB Mn?1), in a 9‐unit‐cell La2/3Sr1/3MnO3 (LSMO) layer via modifying interfacial boundary conditions. Moreover, the LSMO/PbTiO3‐based multilayers and superlattices that consist of PbTiO3/LSMO/NdGaO3 and PbTiO3/LSMO/PbTiO3 interfaces are characterized by two distinct Curie temperatures and coercive fields. The results reveal the feasibility of the interface‐resolved strategy based on boundary modification in fabricating potential devices with multiple accessible states for information storage. The wide‐range modulations on magnetic properties at LSMO/titanate interfaces are explained in terms of binary controls arising from the oxygen octahedral coupling (OOC) and magnetoelectric coupling (MEC). The results not only shed some light on understanding interfacial correlations in oxide heterostructures, but also pave an alternative path for exploring multiple accessible states in all‐oxide‐based electronic devices. 相似文献
996.
用高温熔融-退火扩散法合成了富Co组成的方钴矿化合物CeyFexCo4-xSb12(y=0~0.42),并对化合物的结构和热电性能进行了研究.结果表明:化合物的晶格常数随Ce填充量的增加而线性增加.霍尔系数RH为正值,CeyFexCo4-xSb12化合物表现p型传导.载流子浓度和电导率随Ce填充量的增加而减少.Seebeck系数随Ce填充量的增加及温度的上升而增加.晶格热导率在Ce填充量约为0.29时达到最小值,说明在Sb组成的二十面体空洞中部分填充时,Ce的扰动对声子的散射作用最强.在725K时,组成为Ce0.29Fe1.41Co2.59Sb12.32化合物的最大无量纲热电性能指数达到0.65. 相似文献
997.
报道了p-GaN/Al0.35Ga0.65N/GaN应变量子阱结构的肖特基紫外探测器的制备及性能.器件的测试结果表明,在p-GaN/Al0.35Ga0.65N/GaN双异质结中强烈的压电极化和Stark效应共同作用下使得器件在正偏和反偏时的响应光谱都向短波方向移动了10nm.零偏下器件在280nm时的峰值响应为0.022A/W,在反向偏压为1V时,峰值响应增加到0.19A/W,接近理论值.在正向偏压下器件则呈平带状态,并在283和355nm处分别出现了两个小峰.在考虑极化的情况下,通过器件中载流子浓度分布的变化解释了器件在不同偏压下的响应特性,发现p-GaN/Al0.35Ga0.65N/GaN中的极化效应对器件的响应特性影响很大,通过改变偏压和适当的优化设计可以使探测器在紫外波段进行选择性吸收. 相似文献
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