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Ning Cai Jing Zhang Mingfei Xu Min Zhang Peng Wang 《Advanced functional materials》2013,23(28):3539-3547
The judicious design of 3D giant organic dye molecules to enable the formation of a porous photoactive layer on the surface of titania is one of the viable tactics to abate the adverse interfacial charge recombination in dye‐sensitized solar cells (DSCs) employing outer‐sphere redox couples. Here 2′,6′‐bis(octyloxy)‐biphenyl substituted dithieno[3,2‐b:2′,3′‐d]pyrrole segment is constructed and employed as the π‐linker of a high molar absorption coefficient organic push‐pull dye. With respect to its congener possessing the hexyl substituted dithieno[3,2‐b:2′,3′‐d]pyrrole linker, the new dye can self‐assemble on the surface of titania to afford a porous organic coating, which effectively slow down the kinetics of charge recombination of titania electrons with both outer‐sphere tris(1,10‐phenanthroline)cobalt(III) ions and photooxidized dye molecules, improving the cell photovoltage. In addition, the diminishments of charge recombination via modulating the microstructure of interfacial functional zone can also overcompensate the disadvantageous impact of reduced light‐harvesting and evoke an enhanced photocurrent output, bringing forth an efficiency improvement from 7.5% to 9.3% at the 100 mW cm?2, simulated AM1.5 conditions. 相似文献
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在接入网中,低成本、小尺寸的同轴结构封装10 Gb/s光接收组件起着非常重要的作用。在微波频段,封装器件引入的寄生参数已经成为制约其高频特性的主要因素之一。基于传输线理论,建立了包含芯片、金丝、管座的小信号等效电路模型。等效电路元件与实际封装器件有对应的关系。组件高频特性随元件参数值变化而变化。仿真结果表明金丝对其高频特性影响很严重。为了减小金丝电感,提出一种优化方案。并结合实际工艺条件,制作了样品,实验结果表明该样品的传输速率达到10 Gb/s,满足10 Gb/s光网络传输的要求。 相似文献
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Chen Yang Zhiwei Zheng Muhammad Rizwan Younis Chenle Dong Yahong Chen Shan Lei Dong-Yang Zhang Jiayingzi Wu Xueqing Wu Jing Lin Xiansong Wang Peng Huang 《Advanced functional materials》2021,31(20):2101372
Patients with diabetes mellitus (DM) suffer from a high risk of fractures and poor bone healing ability. Surprisingly, no effective therapy is available to treat diabetic bone defect in clinic. Here, a 3D printed enzyme-functionalized scaffold with multiple bioactivities including osteogenesis, angiogenesis, and anti-inflammation in diabetic conditions is proposed. The as-prepared multifunctional scaffold is constituted with alginate, glucose oxidase (GOx), and catalase-assisted biomineralized calcium phosphate nanosheets (CaP@CAT NSs). The GOx inside scaffolds can alleviate the hyperglycemia environment by catalyzing glucose and oxygen into gluconic acid and hydrogen peroxide (H2O2). Both the generated H2O2 as well as the overproduced H2O2 in DM can be scavenged by CaP@CAT NSs, while the initiated hypoxic microenvironment stimulates neovascularization. Moreover, the incorporation of CaP@CAT NSs not only enhance the mechanical property of the scaffolds, but also facilitate bone regeneration by the degraded Ca2+ and PO43− ions. The remarkable in vitro and in vivo outcomes demonstrate that enzymes functionalized scaffolds can be an effective strategy for enhancing bone tissue regeneration in diabetic conditions, underpinning the potential of multifunctional scaffolds for diabetic bone regeneration. 相似文献
997.
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
998.
Phase‐Transited Lysozyme as a Universal Route to Bioactive Hydroxyapatite Crystalline Film 下载免费PDF全文
Yuan Ha Jie Yang Fei Tao Qian Wu Yunjia Song Haorong Wang Xu Zhang Peng Yang 《Advanced functional materials》2018,28(4)
A key factor for successful design of bioactive complex, organic–inorganic hybrid biomaterials is the facilitation and control of adhesion at interfaces, as many current synthetic biomaterials are inert, lacking interfacial bioactivity. In this regard, the development of a simple, unified way to biofunctionalize diverse organic and inorganic materials toward biomineralization remains a critical challenge. In this report, a universal biomimetic mineralization route that can be applied to virtually any type and morphology of scaffold materials is provided to induce nucleation and growth of hydroxyapatite (HAp) crystals based on phase‐transited lysozyme (PTL) coating. Surface‐anchored abundant functional groups in the PTL enrich the interface with strongly bonded calcium ions, facilitating the formation of HAp crystals in simulated body fluid with the morphology and alignment being similar to that observed in natural HAp in mineralized tissues. By the adhesion of amyloid contained in the PTL, such protein assembly could readily integrate HAp on ceramics, metals, semiconductors, and synthetic polymers irrespective of their size and morphology, with robust bonding stability and corresponding ultralow wear extent under normal bone pressure. This strategy successfully improves the in vivo osteoconductivity of Ti‐based implant, underpinning the expectation for such biomaterial in future biointerface and tissue engineering. 相似文献
999.
Porphyrinic Metal–Organic Frameworks Coated Gold Nanorods as a Versatile Nanoplatform for Combined Photodynamic/Photothermal/Chemotherapy of Tumor 下载免费PDF全文
Jin‐Yue Zeng Ming‐Kang Zhang Meng‐Yun Peng Dan Gong Xian‐Zheng Zhang 《Advanced functional materials》2018,28(8)
In this paper, a simple, but effective method is reported to construct the core?shell gold nanorod@metal–organic frameworks (AuNR@MOFs) as a multifunctional theranostic platform by using functionalized AuNRs as seed crystal for the growth of porphyrinic MOFs on the surface of AuNR. Such a delicate tunable core?shell composite not only possesses the improved drug loading efficiency, near‐infrared light‐trigger drug release, and fluorescence imaging, but also can produce reactive oxygen species as well as photothermal activity to achieve combined cancer therapy. It is further demonstrated that the camptothecin loaded AuNR@MOFs show distinctively synergistic efficiency for damaging the cancer cell in vitro and inhibiting the tumor growth and metastasis in vivo. The development of this high‐performance incorporated nanostructure will provide more perspectives in the design of versatile nanomaterials for biomedical applications. 相似文献
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