检索结果-南通市图书馆

A water-stable metal-organic framework as a luminescent Fe^(3+) sensor under weak acidic and weak basic conditions

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2017年第12期60卷 1581-1587页

作者： Yali Zhu Xinhui Zhou Liang Li Yujian You Wei Huang Key laboratory for Organic Electronics and Information Displays & Institute of advanced Materials Nanjing University of Posts &Telecommunications Key laboratory of Flexible Electronics & Institute of advanced Materials Jiangsu National Synergetic Innovation Center for Advanced Materials Nanjing Tech University

A three-dimensional （3D） metal-organic framework （MOF） ZnL＇O.5H20＂O.75DMF （H2L=9-（pyridin-4-yl）-9H-carbazole- 3,6-dicarboxylic acid, DMF=N,N-dimethylformamide） has been synthesized under solvotherrnal condition. Crystal structure analysis shows that, in ZnL, each dinuclear Zn2（COO）2 unit is doubly-bridged to the other two by the carbazole moieties to form the 1D chains, which are further connected together by pyridine moieties to lead to the 3D framework. ZnL exhibits both high structural stability and good luminescent stability in water with the pH range of 4-10. ZnL displays the luminescent quenching response for Fe3＋ in water with good linear correlation between the quenching efficiency and the concentration with Ksv of 10800 M 1 in the low concentration range of 0-0.1 mM. Interestingly, it is observed that the sensing performance for Fe3＋ is stable in the pH range of 4-9, enabling ZnL to detect Fe3＋ ions in weak acidic and weak basic solutions.

关键词： 9-(pyridin-4-yl)-9H-earbazole-3,6-dicarboxylie acid MOFs water stability Fe3+ sensor pH

Secure Localization Technology Based on Dynamic Trust Management in Wireless sensor Networks

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2021年第4期30卷 759-768页

作者： LI Peng YU Xiaotian XU He WANG Ruchuan School of Computer Science and Technology Nanjing University of Posts and Telecommunications Jiangsu High Technology Research Key laboratory for Wireless sensor Networks

Wireless sensor networks have critical applications in various fields, and the algorithm of their secure localization has become a vital technology to support a network. In the light of the self-organization, random deployment and dynamic topology, the localization process is vulnerable to various kinds of malicious attacks. The model of dynamic trust management for a given node is proposed to deal with security concerns in wireless sensor networks. The trust computation is divided into three stages, which are the stage of trust initialization,trust establishment, and trust evolution. The initial value of a global trust relationship is established through a corresponding global trust relation graph in the initial stage of trust. The trust value of each node is calculated by the attribute value in the stage of trust establishment. In the evolution of trust, the iterative process of trust value is accelerated via the finite state machine. Compared with the existing wireless sensor networks, simulation results show that the proposed security localization technology method can resist many kinds of attacks with low communication and time consumption.

关键词： Wireless sensor networks Secured localization Dynamic trust management Finite state machines

Wire-like nano-polyaniline deposited electrochemically in a reverse micelle electrolyte as a p H sensor

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2015年第10期22卷 1115-1119页

作者： Fei Zhao Han-dong Jiao Shi-qiang Zhao State Key laboratory of advanced Metallurgy University of Science and Technology Beijing

Wire-like polyaniline(PANI) films were successfully electrodeposited onto an indium tin oxide(ITO) substrate using a pulse galvanostatic method(PGM) in a reverse micelle electrolyte. The as-prepared PANI films were electrochemically analyzed by cyclic voltammetry and electrochemical impedance spectroscopy in 1 mol·L-1 HCl O4 solution. It is found that the as-prepared PANI films are highly porous, exhibit the diameters of approximately 100 nm and the lengths exceeding 3 μm, and have favorable electrochemical activities. Furthermore, the as-prepared wire-like PANI films show a good linear relationship of the potentiometric response curve over the p H value range of 3–10 with a slope of 74.13 m V·p H-1 in 0.5 mol·L-1 K2HPO4 basal solutions. The results demonstrate that the prepared wire-like PANI films are promising p H sensors.

关键词： electrodeposition polymers sensors thin films

Laser image refractive index sensor based on the combination of a coreless optical fiber and a digital camera

在线全文

学校读者我要写书评

暂无评论

Optoelectronics Letters 2025年第02期 65-68页

作者： GUO Jingzhong LAN Feng CHEN Xiang LIU Haifeng Xi'an Institute of Space Radio Technology Key laboratory of Optoelectronic sensor and Sensing Network Technology College of Electronic Information and Optical Engineering Nankai University

As a laser passes through a scattering medium,the light interacts with the irregular reflections within the medium,resulting in light scattering and the formation of *** this paper,an image sensor based on the combination of a coreless optical fiber and a digital camera is proposed for liquid refractive index sensing *** coreless fiber is used as a sensing unit,and the change in the speckle pattern is measured using the digital correlation method to detect the magnitude of the liquid's refractive *** experimental results indicate that the laser image sensing technique is capable of effectively distinguishing liquid samples with refractive indices ranging from 1.332 8 to1.390 8,with a sensing sensitivity of-1.306 ***,the laser image sensing technique,with its advantages of high experimental reproducibility,simple system design,remote over-control,holds great research significance and potential application in laser communication and sensor integration.

关键词：

A twist sensor based on polarization-maintaining fibers with different cladding diameters

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Nanotechnology and Precision Engineering 2021年第2期4卷 1-8页

作者： Xiaoqi Liu Yange Liu Zhi Wang Tianjin Key laboratory of Optoelectronic sensor and Sensing Network Technology Institute of Modern OpticsNankai UniversityTianjin 300350China

A fiber twist sensor using a Sagnac interferometer incorporating a tapered polarization-maintaining fiber(PMF)is *** transmission properties of the sensor are investigated both theoretically and *** the optoelastic effect,which depends on fiber geometry,the modal and group birefringences of the PMF can be controlled by applying different twist *** spectral wavelength shifts,free spectral ranges,and transmission losses of the original,microtapered,and etched PMFs were ***,the interference dips for the etched PMF move in opposite *** a result,the proposed PMF-based sensor could have multiparameter sensing applications.

关键词： Fiber-optic Fiber-optic sensor Polarization-maintaining Twist sensor

A ratiometric fluorescent sensor for tracking Cu(Ⅰ) fluctuation in endoplasmic reticulum

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2019年第4期62卷 465-474页

作者： Jungu Guo Hao Yuan Yuncong Chen Zhongyan Chen Menglong Zhao Liang Zou Yi Liu Zhipeng Liu Qiang Zhao Zijian Guo Weijiang He State Key laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing University Key laboratory for Organic Electronics and Information Displays & Jiangsu Key laboratory for Biosensors Institute of Advanced Materials(IAM) Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM)Nanjing University of Posts & Telecommunications Key laboratory of Flexible Electronics (KLOFE) & Institute of advanced Materials (IAM) Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM) Nanjing Tech University (NanjingTech)

A two-photon ratiometric fluorescent sensor for Cu^+ in endoplasmic reticulum(ER), CNSB, was developed via coumarin/ASBD integration based on FRET mechanism. In solution, CNSB shows reversible, highly-specific ratiometric response to Cu^+ .Moreover, CNSB exhibits suitable K_d value, suggesting the possibility of detecting Cu^+ in the living cells. The probe can enter the MCF-7 cells easily and specifically locates in the ER. The highly specific ratiometric response of CNSB toward Cu^+ in MCF-7 cells provides the sensor the capacity to visualize both exogenous and endogenous Cu^+ in the ER via fluorescence ***, CNSB was utilized to detect the fluctuation and distribution of Cu^+ under ER stress in MCF-7 cells, which confirmed directly the relationship between Cu^+ enhancement and ER stress. Meanwhile, the two-photon ability of coumarin facilitated the sensor to visualize Cu^+ fluctuation via two-photon fluorescence imaging. In addition, the spatial distribution of Cu^+ in the heart slice of the 14-day-old rat was demonstrated using CNSB. This study demonstrates the promising potential of CNSB in clarifying the Cu^+ -dependent signaling in the ER stress-related diseases.

关键词： Cu(Ⅰ) ratiometric two-photon endoplasmic reticulum-targeting endoplasmic reticulum stress heart tissue slice

A time domain multiple-CFOs and CIRs estimation algorithm over wireless multimedia sensor networks

在线全文

学校读者我要写书评

暂无评论

High Technology Letters 2009年第3期15卷 294-300页

作者：姜建 Key laboratory of Wireless sensor Network & Communication Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences

Channel parameters estimation in an orthogonal for the receiver station is a multi-dimensional （MD） frequency division multiple access （OFDMA） system optimization problem, because every user node has a separate local oscillator and every transmitter to receiver link has individual carrier frequency offset （CFO） and channel impulse response （CIR） parameters. In order to reduce the computational complexity for MD optimization, a time domain CFOs and CIRs estimation algorithm over the OFDMA based wireless multimedia sensor networks （WMSN） is proposed in this paper. In this algorithm, the receiver station can decouple the signal from every node by correlation based on specially designed training sequences, so that the MD optimization problem is simplified to an 1-D optimal problem. It is proved that the multiple CFOs can be identified from the correlation result using the phase shift of the consecutive training se- quences. Based on the CFOs estimation result, the CIRs can then he estimated according to the minimum mean square error （MMSE） criterion. The theoretic analysis and simulation results show that the proposed algorithm can effectively decouple the signal from different user nodes and the bit error rate （BER） per- formance curves are close to the ideal estimation when the user number is not large.

关键词： wireless multimedia sensor networks (WMSN) orthogonal frequency division multiple access (OFDMA) multiple carrier frequency offsets (CFOs) multiple channel impulse responses (CIRs) minimum mean square error (MMSE)

Liquid crystal between two distributed Bragg reflectors enables multispectral small-pitch spatial light modulator

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2022年第8期11卷 1643-1645页

作者： Junghyun Park Kanghee Won Young Kim advanced sensor Lab Device Research CenterSamsung Advanced Institute of TechnologySuwonRepublic of Korea

The ability of controlling the phase of light at the subwavelength scale can be a game-changer due to its extraordinally wide angle-range in the wavefront shaping. By combining two conventional material and configurat... 详细信息

关键词： crystal enable light

Secure Two-Party Distance Computation Protocol Based on Privacy Homomorphism and Scalar Product in Wireless sensor Networks

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2016年第4期21卷 385-396页

作者： Haiping Huang Tianhe Gong Ping Chen Reza Malekian Tao Chen Nanjing University of Posts and Telecommunications Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Department of Electrical Electronic and Computer EngineeringUniversity of Pretoria

Numerous privacy-preserving issues have emerged along with the fast development of the Internet of Things. In addressing privacy protection problems in Wireless sensor Networks （WSN）, secure multi-party computation is considered vital, where obtaining the Euclidian distance between two nodes with no disclosure of either side＇s secrets has become the focus of location-privacy-related applications. This paper proposes a novel Privacy-Preserving Scalar Product Protocol （PPSPP） for wireless sensor networks. Based on PPSPP, we then propose a Homomorphic-Encryption-based Euclidean Distance Protocol （HEEDP） without third parties. This protocol can achieve secure distance computation between two sensor nodes. Correctness proofs of PPSPP and HEEDP are provided, followed by security validation and analysis. Performance evaluations via comparisons among similar protocols demonstrate that HEEDP is superior; it is most efficient in terms of both communication and computation on a wide range of data types, especially in wireless sensor networks.

关键词： secure two-party computation privacy-preserving wireless sensor networks scalar product distancecalculation privacy homomorphism