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91.
Jie Song Pengyi Zhang Mohammed Alkubati Yubin Bao Ge Yu 《Digital Communications & Networks》2022,8(4):466-475
Due to the complexity of blockchain technology, it usually costs too much effort to build, maintain and monitor a blockchain system that supports a targeted application. To this end, the emerging “Blockchain as a Service” (BaaS) makes the blockchain and distributed ledgers more accessible, particularly for businesses, by reducing costs and overheads. BaaS combines the high computing power of cloud computing, the pervasiveness of IoT and the decentralization of blockchain, allowing people to build their own applications while ensuring the transparency and openness of the system. This paper surveys the research outputs of both academia and industry. First, it introduces the representative architectures of BaaS systems and then summarizes the research contributions of BaaS from the technologies for service provision, roles, container and virtualization, interfaces, customization and evaluation. The typical applications of BaaS in both academic and practical domains are also introduced. At present, the research on the blockchain is abundant, but research on BaaS is still in its infancy. Six challenges of BaaS are concluded in this paper for further study directions. 相似文献
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Immobilization of Pt Nanoparticles via Rapid and Reusable Electropolymerization of Dopamine on TiO2 Nanotube Arrays for Reversible SERS Substrates and Nonenzymatic Glucose Sensors 下载免费PDF全文
Jingsheng Cai Jianying Huang Mingzheng Ge James Iocozzia Zhiqun Lin Ke‐Qin Zhang Yuekun Lai 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(19)
Inspired by mussel‐adhesion phenomena in nature, polydopamine (PDA) coatings are a promising route to multifunctional platforms for decorating various materials. The typical self‐polymerization process of dopamine is time‐consuming and the coatings of PDA are not reusable. Herein, a reusable and time‐saving strategy for the electrochemical polymerization of dopamine (EPD) is reported. The PDA layer is deposited on vertically aligned TiO2 nanotube arrays (NTAs). Owing to the abundant catechol and amine groups in the PDA layer, uniform Pt nanoparticles (NPs) are deposited onto the TiO2 NTAs and can effectively prevent the recombination of electron–hole pairs generated from photo‐electrocatalysis and transfer the captured electrons to participate in the photo‐electrocatalytic reaction process. Compared with pristine TiO2 NTAs, the as‐prepared Pt@TiO2 NTA composites exhibit surface‐enhanced Raman scattering sensitivity for detecting rhodamine 6G and display excellent UV‐assisted self‐cleaning ability, and also show promise as a nonenzymatic glucose biosensor. Furthermore, the mussel‐inspired electropolymerization strategy and the fast EPD‐reduced nanoparticle decorating process presented herein can be readily extended to various functional substrates, such as conductive glass, metallic oxides, and semiconductors. It is the adaptation of the established PDA system for a selective, robust, and generalizable sensing system that is the emphasis of this work. 相似文献
94.
Healing Effect of Controlled Anti‐Electromigration on Conventional and High‐Tc Superconducting Nanowires 下载免费PDF全文
Xavier D. A. Baumans Joseph Lombardo Jérémy Brisbois Gorky Shaw Vyacheslav S. Zharinov Ge He Heshan Yu Jie Yuan Beiyi Zhu Kui Jin Roman B. G. Kramer Joris Van de Vondel Alejandro V. Silhanek 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(26)
The electromigration process has the potential capability to move atoms one by one when properly controlled. It is therefore an appealing tool to tune the cross section of monoatomic compounds with ultimate resolution or, in the case of polyatomic compounds, to change the stoichiometry with the same atomic precision. As demonstrated here, a combination of electromigration and anti‐electromigration can be used to reversibly displace atoms with a high degree of control. This enables a fine adjustment of the superconducting properties of Al weak links, whereas in Nb the diffusion of atoms leads to a more irreversible process. In a superconductor with a complex unit cell (La2?x Cex CuO4), the electromigration process acts selectively on the oxygen atoms with no apparent modification of the structure. This allows to adjust the doping of this compound and switch from a superconducting to an insulating state in a nearly reversible fashion. In addition, the conditions needed to replace feedback controlled electromigration by a simpler technique of electropulsing are discussed. These findings have a direct practical application as a method to explore the dependence of the characteristic parameters on the exact oxygen content and pave the way for a reversible control of local properties of nanowires. 相似文献
95.
Peng Chuanqi Gao Xiaofei Xu Jing Du Bujie Ning Xuhui Tang Shaoheng Bachoo Robert M. Yu Mengxiao Ge Woo-Ping Zheng Jie 《Nano Research》2017,10(4):1366-1376
A major clinical translational challenge in nanomedicine is the potential of toxicity associated with the uptake and long-term retention of non-degradable nanoparticles (NPs) in major organs.The development of inorganic NPs that undergo renal clearance could potentially resolve this significant biosafety concern.However,it remains unclear whether inorganic NPs that can be excreted by the kidneys remain capable of targeting tumors with poor permeability.Glioblastoma multiforme,the most malignant orthotopic brain tumor,presents a unique challenge for NP delivery because of the blood-brain barrier and robust blood-tumor barrier of reactive microglia and macroglia in the tumor microenvironment.Herein,we used an orthotopic murine glioma model to investigate the passive targeting of glutathione-coated gold nanoparticles (AuNPs) of 3 nm in diameter that undergo renal clearance and 18-nm AuNPs that fail to undergo renal clearance.Remarkably, we report that 3-nm AuNPs were able to target intracranial tumor tissues with higher efficiency (2.3x relative to surrounding non-tumor normal brain tissues) and greater specificity (3.0x)than did the larger AuNPs.Pharmacokinetics studies suggested that the higher glioma targeting ability of the 3-nm AuNPs may be attributed to the longer retention time in circulation.The total accumulation of the 3-nm AuNPs in major organs was significantly less (8.4x) than that of the 18-nm AuNPs.Microscopic imaging of blood vessels and renal-clearable AuNPs showed extravasation of NPs from the leaky blood-tumor barrier into the tumor interstitium.Taken together,our results suggest that the 3-nm AuNPs,characterized by enhanced permeability and retention,are able to target brain tumors and undergo renal clearance. 相似文献
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Insight into In Situ Amphiphilic Functionalization of Few‐Layered Transition Metal Dichalcogenide Nanosheets 下载免费PDF全文
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Liu Daobin Wu Chuanqiang Chen Shuangming Ding Shiqing Xie Yaofeng Wang Changda Wang Tao Haleem Yasir A. ur Rehman Zia Sang Yuan Liu Qin Zheng Xusheng Wang Yu Ge Binghui Xu Hangxun Song Li 《Nano Research》2018,11(4):2217-2228
Nano Research - Atomically dispersed catalysts have attracted attention in energy conversion applications because their efficiency and chemoselectivity for special catalysis are superior to those... 相似文献