- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Plasmon-active optical fiber functionalized by metal organic framework for pesticide detection
摘要： Functional plasmonic fiber for detection and on-line monitoring of organophosphorus pesticides in water or model soil samples is described. The appearance of the plasmon absorption band was realized through the deposition of a thin gold layer on the naked core of multimode optical fiber. The metalorganic frameworks (MOF-5) layer was deposited on the gold surface for the introduction of a high affinity towards the target pesticides. The MOF-5 layer affords the extraction of pesticides and their concentration primarily in the “plasmon evanescent wave” space, allowing the detection by the shift of plasmon absorption band. The growth of MOF-5 layer was confirmed using the Raman, XPS and XRD measurements. The entrapping of pesticides was checked using the Raman spectroscopy and ellipsometry, which also indicate the corresponding changes of MOF-5 refractive index. The series of further experiments demonstrate the applicability of proposed fiber sensor for detection of pesticides in soil without the false signals from surrounding media. The main advantages of proposed sensor can be attributed to simplicity, high sensitivity, low cost and the absence of organic solvents for the probe treatment.
关键词： Optical fiber,Organophosphorus pesticides detection,Metal–organic frameworks,Surface plasmon resonance,Sensor
更新于2025-09-12 10:27:22
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Synthesis and characterization of poly(methyl methacrylate) co-doped with Tb(tmhd)3 – Rhodamine B for luminescent optical fiber applications
摘要： Currently, there is a growing interest in the development of multi-colored materials based on the combination of two or more systems (organic or inorganic) as a strategy to take advantage of their combined physical or chemical properties. These multi-colored materials have found potential applications as sensors, amplifiers, and optical fibers. In this work, the physical characteristics of poly(methyl methacrylate) (PMMA) doped with Terbium(III)-tris-(2,2,6,6-tetramethyl-3,5-heptanedionate) (Tb(tmhd)3) at 1.57–1.58 mmol and Rhodamine B (RhB) at different concentrations were analyzed. The emission obtained from these samples (multichromophoric samples) varied as function of RhB concentration due to an efficient energy transfer process (33–65%). The role of PMMA as inert matrix that assists in the recombination process was confirmed by FTIR and Raman spectra analysis. Moreover, an improvement in thermal resistance of the materials was observed due to the presence of the dopants during the polymerization process.
关键词： Poly(methyl methacrylate),Rhodamine B,Tb(tmhd)3,Energy transfer,Luminescent optical fiber
更新于2025-09-12 10:27:22
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Design on Program-Controlled Initiation System of the SCB explosive devices Based on Optical Fiber Communication
摘要： A control system for Semiconductor Bridge explosive devices is designed based on optical fiber Communication, which can make the explosive devices perform better in the complex electromagnetic environment. By the combination of programmable bus controller, ignition unit and the optical fiber communication, the ignition of the explosive devices in chronological order could be realized. After the system design was completed, the major function and anti-electromagnetic interference capability were tested. The results indicated that the system had remote-control ability, high reliability, high security and good electromagnetic compatibility. The system can be used in more complicated electromagnetic environment than the conventional initiating explosive devices.
关键词： programmable bus controller,ignition unit,electromagnetic compatibility,Semiconductor Bridge explosive devices,optical fiber communication
更新于2025-09-12 10:27:22
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Employment of optical fibers for RC bond-slip characterization
摘要： Some features as workability, high durability and low cost of production have contributed for reinforced concrete (RC) be largely used worldwide. However, environmental actions and the natural material decaying are the most common processes that contribute for the loss of the physical-mechanical properties of the RC structures. When the bond between the concrete and the reinforcing rebar are affected, the results can be extremely dramatic and unpredicted. In this work, an optical fiber device for the monitoring of the bond-slip of old RC structures, where less intrusive techniques need to be considered, is proposed and tested. The sensor developed is based on the fiber Bragg grating (FBG) technology, inscribed in silica optical fiber. A pull-out test was carried out in a RC specimen, following the recommendations of the Annex D of the EN 10080. The results showed that the bond-slip optical sensors are capable to measure micro-displacements, with lower intrusiveness. Therefore, they can be used for monitoring the bond-slip of old RC structures as way of to collect information, essential to assist the owners to adopt cost effective, efficient and safer maintenance measures.
关键词： heritage constructions,optical fiber,SHM,RC,Bond-slip,FBG sensors
更新于2025-09-12 10:27:22
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Optical fiber microphones based on twice envelope demodulation algorithm
摘要： In order to improve the detection performance of a sound signal with the phase-sensitive optical time domain reflectometer, a demodulation algorithm based on twice envelope extraction is reported for the distributed sensing of sound signal. After the introduction of the sound sensing principle with the optical fiber microphone, a sensitivity enhancement structure which is composed by a piece of austenitic sheet is chosen for the detection of sound signal generated by the loudspeaker. The complete algorithm flow chart of twice envelope demodulation algorithm is then introduced. The first envelope extraction of the time-domain signal is acquired by the wavelet decomposition method in order to search the smooth region in the curve of time-domain signal. After the threshold comparison, the second envelope extraction of the smooth segment is realized by the envelope estimation algorithm, which could be used for the elimination of the noise factor. A high speed acquisition system based on FPGA is also proposed which could achieve signal acquisition through high speed AD acquisition module. The experimental results verify the effectiveness of the demodulation method. It can detect and locate the sound signal in the frequency range of 300 ?1 kHz at a distance of 1000 m with the position error within 20 m. This demodulation method provides a new solution for the detection of sound signal by the phase-sensitive optical time-domain reflectometer.
关键词： Optical fiber microphones,Envelope extraction,Sound sensing,Φ-OTDR
更新于2025-09-12 10:27:22
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A Review: Evolution and Diversity of Optical Fibre Plasmonic Sensors
摘要： The purpose of this review is to bring to the attention of the wider research community how two quite different optical sensory techniques were integrated resulting in a sensor device of exceptional sensitivity with wide ranging capability. Both authors have collaborated over a 20 year period, each researching initially surface plasmon resonance (SPR) and optical fibre Bragg grating devices. Our individual research, funded in part by EPSRC and industry into these two areas, converged, resulting in a device that combined the ultra-sensitive working platform of SPR behavior with that of fibre Bragg grating development, which provided a simple method for SPR excitation. During this period, they developed a new approach to the fabrication of nano-structured metal coatings for plasmonic devices and demonstrated on fibre optic platform, which has created an ultra-sensitive optical sensing platform. Both authors believe that the convergence of these two areas will create opportunities in detection and sensing yet to be realised. Furthermore, giving the reader “sign-post” research articles to help to construct models to design sensors and to understand their experimental results.
关键词： gratings,optical fiber sensors,bio-sensors,plasmonic nanostructures
更新于2025-09-12 10:27:22
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[IEEE 2019 SBFoton International Optics and Photonics Conference (SBFoton IOPC) - Sao Paulo, Brazil (2019.10.7-2019.10.9)] 2019 SBFoton International Optics and Photonics Conference (SBFoton IOPC) - Online Monitoring of Cell Growth on PDMS-PDMS Reversible Microfluidic Bioreactor Integrated to Optical Fiber Sensor
摘要： A microfluidic bioreactor was fabricated by curing PDMS over 3D-printed molds, and it contains microchannels and perfusion chambers instrumented with optical fibers for the online analysis of the cellular growth. The channels were designed for allowing both the complete mixture of reagents and the possibility of generation of concentration gradients, and the perfusion chambers are isolated from them by polycarbonate membranes, providing a chemical environment with a constant concentration of nutrients for the cells. The optical fibers are laterally inserted in the chambers, and the monitoring of cells concentration is based on the quasi-elastic light scattering: as the total number of cells grows, there is an increase on the dispersion of the reflected intensity data, and the autocorrelation of the values allows the inference of the concentration. The sensor signals obtained during the fermentation of S. cerevisiae were equivalent to the cell counting on the Neubauer chamber using an optical microscope, leading to a value of the maximum specific growth rate μm of 0.50 h-1. This optical monitoring system has proven to be easily manufacturable and capable of performing fast screening and online monitoring of the microbial kinetics.
关键词： microbial kinetics,online monitoring,optical fiber sensor,quasi-elastic light scattering,Microfluidic bioreactor
更新于2025-09-12 10:27:22
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[IEEE TENCON 2019 - 2019 IEEE Region 10 Conference (TENCON) - Kochi, India (2019.10.17-2019.10.20)] TENCON 2019 - 2019 IEEE Region 10 Conference (TENCON) - Dispersion Behavior of Fundamental Supermodes in Homogeneous Strongly Coupled Multicore Optical Fibers for Different Core Counts and Layouts
摘要： In this paper, dispersion behavior of fundamental supermode in homogeneous strongly-coupled multicore fibers (SC-MCFs) have been investigated using the finite element method based simulation platform and MATLAB. Further, to observe the impacts of core count and core layout on the dispersion behavior of fundamental supermode, the core count and layout dependent dispersion behavior have been investigated. The different core layouts considered are namely, linear, triangular, square, rectangular, square lattice structure (SLS), circular and hexagonal one ring structure (ORS) and circular dual ring structure (DRS), while the different core counts are 3-Core, 4-Core, 6-Core, and 12-Core. It has been observed that the core layouts of homogeneous SC-MCFs with the closely packed structures for the different core counts have the lowest value of D(λ) (magnitude of maximum dispersion), as compared to the other layouts. Moreover, it has been observed that in some of the core layouts, such as 4-Core square, 6-Core circular, and 12-Core circular DRS, the dispersion behaviors are nearly flat over a certain wavelength range, which is desirable for the high speed DWDM applications. Therefore, the analysis presented in this paper may be useful for the selection of core layouts in homogeneous SC-MCF with significantly low dispersion level or the flattened dispersion behavior.
关键词： dispersion,core count,Multicore optical fiber,strongly coupled,core layout,homogeneous,supermodes
更新于2025-09-12 10:27:22
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Research on Temperature Sensor Using Rhodamine6G Film coated Microstructure Optical Fiber
摘要： Temperature monitoring plays a key role in the kinetics of chemical reaction. In this paper, a sensitive dynamic temperature monitoring sensor based on the rhodamine6G (R6g) film coated anti-resonance fiber (ARF) is proposed. Because of the high thermo-dependent fluorescence intensity of R6g, the ARF coated with R6g film is highly sensitive to the temperature variation, forming the basis of our proposed temperature sensor application. To enhance the temperature monitoring performance and strengthen the florescence intensity, one of the ARF ends spliced a silica ball for reflecting the input signal, and the other end is inserted with two tapered multimode fiber (MMF), acting as bridges for the input of pump light and the output of signal light, respectively. The dual-peak reached the temperature resolution of 3.946×10-2 °C and 3.991×10-3 °C with linearity of 0.99914 and 0.99953 respectively. The experiment results show that the output fluorescence and pump light intensity decrease with the increasing temperature. These excellent characteristics demonstrate a highly sensitive dual-peak sensor for temperature calibration with wide potential applications, such as environmental monitoring, mine monitoring and other fields of chemical kinetics.
关键词： Rhodamine6G,temperature sensor,Microstructure Optical Fiber
更新于2025-09-12 10:27:22
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Generation of Rogue-Like Pulses via Stimulated Soliton Collision in Dispersion Oscillating Optical Fiber
摘要： In the case of optical supercontinuum generation, rogue waves can appear as rare solitons, possessing anomalously large peak intensity [1]. To stimulate the generation of high-intensity pulses, the use of the modulation of the fiber dispersion is proposed. The propagation of optical soliton in a fiber with variable dispersion is described by nonlinear Schr?dinger equation [2] ????/???? + ??(??(cid:2870)/2)[1 + 0.2sin(2????/??(cid:3040))](??(cid:2870)??/????(cid:2870)) = ??????(??)|??(??, ??)|(cid:2870), where ??(??, ??) is the electric field amplitude, z is the propagation distance, t is the local time, ??(cid:2870) is the group- velocity dispersion parameter, zm is the modulation period, ?? is the nonlinear coefficient, ??(??) = (1 ? ??(cid:3019))??(??) + ??(cid:3019)?(cid:3019)(??) is the nonlinear response function, which includes both instantaneous Kerr nonlinearity and stimulated Raman scattering, ??(cid:3019) = 0.18 [3]. The initial field was assumed as superposition of two in-phase fundamental solitons ??(0, ??) = ??(cid:2868)sech(??/??(cid:2868) ? ??/2) + ??(cid:2868)sech(??/??(cid:2868) + ??/2), where ??(cid:2868) = 1.13 ps is the initial pulse width, ?? = 6 is the initial pulse separation. In a fiber without dispersion modulation (zm=∞) the collision of two in- phase solitons is suppressed due to effect of stimulated Raman scattering. Dispersion modulation with zm=0.85 km induces fusion of the solitons into high-intensity pulse at z=5 km (fig.1a). The peak power (fig.1a, top) is two times higher than the same for unperturbed case (zm=∞). The high-intensity pulse propagates up to z=10 km before fission onto two solitons propagating with different group velocities. The eigenvalue analysis of the soliton propagation in the fig.1b is shown. Each of the discrete eigenvalue λ of Zakharov-Shabat spectral problem is associated with fundamental soliton [3]. The real part Re(λ) and imaginary part Im(λ) give the soliton frequency shift and soliton energy correspondingly. Initial field ??(0, ??) has two imaginary eigenvalues λ1= i0.502 and λ2= i0.497. At the initial state of propagation (z<5 km) these eigenvalues are changed synchronously (fig.1b). The high intensity pulse (5 km<z<10 km) is formed by two-soliton breather. Nonlinear interference between these solitons gives high-intensity oscillations (fig.1a, top). In the process of the soliton fusion the energy of the first soliton increases while the energy of the second is suppressed. At z=7.5 km we have Im(λ1)=0.6 (curve 1, fig.1b) and Im(λ2)=0.04 (curve 2, fig.1b). Due to stimulated Raman scattering, the solitons acquire different group velocities, which are defined by Re(λ) (fig.1b, bottom). As a result, the breather splits into two separate solitons (z>10 km). The dispersion oscillation fibers rearranges eigenvalues in the complex plane [Re(λ), Im(λ)]. This phenomenon can be used for all-optical encoding in fiber-optics eigenvalue communication links.
关键词： stimulated Raman scattering,soliton collision,nonlinear Schr?dinger equation,rogue waves,dispersion oscillating optical fiber
更新于2025-09-12 10:27:22