Fiber Grinding Research Articles

Fiber-end control algorithm based on back-propagation neural network

The evenness of the trajectory of the optical fiber grinding track has a substantial effect on the quality of the transmission of optical signals. To boost this transmission quality, we present a blueprint for the trajectory of the optical fiber grinding track, together with the recently introduced equipment for shaping the end-face of the optical fiber. This model establishes the correlation between the grinding trajectory and the rotational speed of the grinding motor, enabling control of the grinding trajectory of the optical fiber connector by manipulating the motor’s rotation speed. Three-speed control methods, namely the Proportional-Integral-Derivative (PID) controller, fuzzy control algorithm, and Back-Propagation (BP) neural network PID control algorithm, were compared for effectiveness using Matlab/Simulink simulation software. The BP neural network displayed exceptional performance, leading us to implement the PID control algorithm to govern the speed of the grinding motor. Our experimental findings validate the superior efficacy of the BP neural network PID control algorithm in governing the speed of the grinding motor, thereby ensuring a consistent grinding trajectory for optical fibers.

A controllable humidity sensitivity measurement solution based on a pure FPI fiber tip and the harmonic Vernier effect

Hygroscopic films used to enhance the humidity sensitivity of fiber-optic sensors often experience material aging and nonlinear response issues. To address this issue, this study proposes a controllable humidity sensitivity measurement solution that offers a simple and cost-effective fabrication process without requiring humidity-sensitive material sensitization. The solution is based on a Fabry-Perot interferometer (FPI) fiber tip and the harmonic Vernier effect. By employing a cascade structure of single-mode fiber (SMF)-hollow core fiber (HCF)-no core fiber (NCF) with fiber grinding techniques, the FPI-based fiber sensing probe constructed a resonance cavity to detect small variations in air refractive index (RI) induced by humidity. A reference spectrum, which can flexibly control parameters, such as free spectral range (FSR), contrast, phase, and intensity, is superimposed onto the sensing spectrum acquired by the FPI fiber sensing tip. By extracting features from the internal envelope generated by the harmonic Vernier effect, the mapping relationship between the center wavelength of the inner envelope and the humidity is determined. The harmonic Vernier effect amplifies the humidity sensitivity of the fiber-optic FPI sensing tip, with the magnification factor determined by the optical path length (OPL) detuning of the created reference and sensing spectra. For the harmonic order j = 4, a humidity sensitivity of approximately 76.01 pm/% RH@ 24 ℃ was achieved without using hygroscopic material sensitization. The proposed solution offers numerous advantages and enables high-precision and high environmental reliability humidity monitoring.

High-sensitivity biconical optical fiber SPR salinity sensor with a compact size by fiber grinding technique

For seawater salinity measurement, a high-sensitivity, ultra-compact, and corrosion-resistant biconical optical fiber surface plasmon resonance (SPR) sensor deposited with a 40 nm thick gold film based on fiber grinding technique was fabricated and demonstrated in this article. The ultra-compact biconical sensing structure with different grinding angles were fabricated by applying the optical fiber grinding machine, and the length of the sensing region was only hundreds of microns. The experimental results indicated that when the grinding angle was 14°, the sensor showed the highest sensitivity: a high refractive index sensitivity of 3965 nm/RIU and a high salinity sensitivity of 0.6898 nm/‰. Meanwhile, this biconical sensor had acceptable repeatability and stability. Therefore, this article demonstrated the feasibility of the biconical structure to improve the sensitivity of fiber-based SPR sensors, and provided a novel and practical solution for seawater salinity measurement.

ВОЛОКОННЫЙ СПОСОБ ПОМОЛА МАТЕРИАЛОВ И ВОПРОСЫ ЕГО ПРАКТИЧЕСКОЙ РЕАЛИЗАЦИИ

The problem of fine grinding of materials is voiced and it is shown that for a number of characteristics the existing equipment does not meet modern requirements, and a new development trend is the transfer of grinding machines from simple tools to functionally new systems for obtaining products with desired properties. The article describes the fiber mechanism of grinding materials and provides options for performing both the fibers themselves and the methods of their weaving and the formation of spatial frameworks or sponges. The performed analysis of metal fibers, their properties and production methods makes it possible to assess their possibility of using them as grinding elements that provide high contact stresses in working areas. A design of a fiber apparatus for grinding and dispersing has been developed, which allows the dispersion process to be carried out in a continuous mode and is intended for processing suspensions and pastes. On the example of grinding chalk in a single-section model, the fundamental possibility of obtaining fine powders is shown, which indicates a high disintegrating ability of the fiber grinding method. The directions of practical implementation of the fiber method of grinding materials are substantiated and priority tasks for its development are set.

High-Sensitivity Biconical Optical Fiber Spr Salinity Sensor with a Compact Size by Fiber Grinding Technique

High-Sensitivity Biconical Optical Fiber Spr Salinity Sensor with a Compact Size by Fiber Grinding Technique

Methods for modeling cavitation in pulp fiber grinding processes

This article presents the main results of theoretical studies of the process of hydrodynamic grinding of cellulose suspension, based on mathematical modeling methods. Cavitation currents are a factor in effective milling of cellulose fiber. In this regard, it is necessary to develop a comprehensive model of the occurrence of the cavitation effect with parameterization of the indicators of the energy that arises.

Preparation and characterization of novel microstructure cellulosic sawdust material: application as potential adsorbent for wastewater treatment

The present work investigated the feasibility to develop of a new microstructure of a material from date palm sawdust in order to improve its adsorption properties. The preparation of the material consists of mechanical grinding of fibers, sieving of sawdust, extractibles extraction and then pretreatment with activating agent sulfuric acid at 1% and 40%. It was then followed by chemical treatment using urea by grafting reaction. The phases change due to chemical modification on sawdust particles was examined using Fourier Transform Infrared (FTIR), spectroscopy Scanning Electron Microscopy (SEM), X-ray diffraction analysis (XRD) and BET method. The hydrolysis at 40% has an effect on the increase of the material crystallinity, higher than the hydrolysis at 1%. An increase in the size of crystallites was also observed by XRD measurements. These results were related to the reduction of the amorphous fractions of wood, and, consequently, to the enrichment of the relative crystalline content. Indeed, the degradation of hemicellulose was observed, by FT-IR analysis, for treated samples. The treated sawdust at 40% acid has the better adsorption characters due to high surface area of 135 m2/g as compared to 44.4 m2/g for treated sawdut (1% acid), this is well supported by SEM micrographs wich also suggest has greater number of pores. Based on preliminary satisfactory results, the sawdust date palm provides a valuable addition to the existing conventional processes to better optimize the adsorption capacity along with low-cost potential application in wastewater treatment.

ツインノズルPELIDを用いた砥粒含有ファイバー砥石の開発 第4報 ファイバー径制御法の検討

ツインノズルPELIDを用いた砥粒含有ファイバー砥石の開発 第4報 ファイバー径制御法の検討

Mechanical activation and characterization of micronized cellulose particles from pulp fiber

Ball milling has been widely used for cellulosic fiber pulverization and de-crystallization, but most of the previous milling studies are focused on the micro-structural change and crystallinity reduction of cellulose, few of them have evaluated the systematic influence of milling conditions and the energy efficiency. The objective of the study is to investigate and understand the effect of various ball milling parameters on the pulp fiber grinding performance. Ball mill time, rotational speed, charge ratio, mill ball diameters, and initial moisture content of pulp fiber were studied systematically from planetary ball milling. The pulverized particle size, particle morphology, crystallinity change, bonding disruption, thermal stability, specific surface area, and energy efficiency were evaluated during the milling process. Results revealed that cellulose fiber was mainly pulverized during the early milling stage (˜20 min) and different variables led to changes regarding to the final particle size and shape. After refinement, the crystallinity and the thermal stability of the pulp fiber decreased, from the weakening or disintegration of the inter and intra hydrogen bonds of the cellulose chains. The specific surface area increased by 4˜5 times with the particle size reduction, while the milling energy efficiency decreased after 40 min of milling time.

Development of nano-diamond-containing fiber grinding wheel using twin nozzle PELID

Development of nano-diamond-containing fiber grinding wheel using twin nozzle PELID

HACF-based optical tweezers available for living cells manipulating and sterile transporting

We propose and demonstrate a single fiber optical tweezers based on a hollow annular-core fiber (HACF), which is available for living cells manipulating and sterile transporting due to the hollow structure, there exists a fluidic channel in the fiber, which is naturally a microfluidic passageway in the fluidic environment, both the optical trapping forces (OTF) and the liquid viscous resistances (LVR) play the important roles. We perform the particles manipulating and transporting by adjusting and controlling the net forces of OTF and LVR. We employ the fiber grinding–polishing technology to fabricate the HACF probe, producing the OTFs. We employ the micropump to perform the positive or negative pressure in the hollow hole of the HACF, changing the liquid velocity and direction, adjusting the LVRs. It is ideally suited for rare cells manipulating and sterile transporting. The implantation of the hollow hole and annular waveguide in a HACF provides the availability for particles manipulating and transporting, constitutes a new development for single fiber optical trapping and makes possible of more practical applications in particles manipulating and transporting fields.

Single fiber dual-functionality optical tweezers based on graded-index multimode fiber

We propose and demonstrate single fiber dual-functionality optical tweezers based on a graded-index multimode fiber. By using the multi-angle fiber grinding and polishing technology, we fabricate the multimode fiber tip to be a special tapered shape, contributing to focus the outgoing beam with a large intensity gradient for the first functionality—three-dimensional contactless trapping of a microparticle. By adjusting the radial direction offset between the lead-in single mode fiber and the graded-index multimode fiber, we perform the second functionality—axial shift of the trapped microparticle with respect to the fiber tip without need of moving the fiber probe itself. It is convenient for practical applications. The theoretical and experimental results about the relationship between the radial offset and the equilibrium positions of the microparticle have the good consistency. Tailoring the trap and axial shift of the microparticle based on the graded-index multimode fiber provides convenient avenues for fiber optical tweezers applied in practical researches.

Two-Channel SPR Sensor Combined Application of Polymer- and Vitreous-Clad Optic Fibers.

By combining a polymer-clad optic fiber and a vitreous-clad optic fiber, we proposed and fabricated a novel optic fiber surface plasmon resonance (SPR) sensor to conduct two-channel sensing at the same detection area. The traditional optic fiber SPR sensor has many disadvantages; for example, removing the cladding requires corrosion, operating it is dangerous, adjusting the dynamic response range is hard, and producing different resonance wavelengths in the sensing area to realize a multi-channel measurement is difficult. Therefore, in this paper, we skillfully used bare fiber grinding technology and reverse symmetry welding technology to remove the cladding in a multi-mode fiber and expose the evanescent field. On the basis of investigating the effect of the grinding angle on the dynamic range change of the SPR resonance valley wavelength and sensitivity, we combined polymer-clad fiber and vitreous-clad fiber by a smart design structure to realize at a single point a two-channel measurement fiber SPR sensor. In this paper, we obtained a beautiful spectral curve from a multi-mode fiber two-channel SPR sensor. In the detection range of the refractive rate between 1.333 RIU and 1.385 RIU, the resonance valley wavelength of channel Ⅰ shifted from 622 nm to 724 nm with a mean average sensitivity of 1961 nm/RIU and the resonance valley wavelength of channel Ⅱ shifted from 741 nm to 976 nm with a mean average sensitivity of 4519 nm/RIU.

Reflective-distributed SPR sensor based on twin-core fiber

We propose and demonstrate a reflective-distributed surface plasmon resonance (SPR) sensor based on the twin-core fiber. Firstly, we study the effects of the fiber dual tapered (DT) probe grinding angle on the SPR dynamic range. The results show that for larger grinding angles, the resonance wavelength increases, resulting in a higher testing sensitivity. By using this method, we can make the sensor operate in an optimal waveband. Secondly, on the basis of the results above, we grind the DT probe to be an asymmetric wedge shape to configure two grinding angles (6° and 17°) to realize the distributed sensing. Results show that, with the refractive index detecting a range of 1.333–1.385, we can get two separated sensing zones, 591–715nm and 729–966nm, the testing sensitivity are 2385nm/RIU and 4558nm/RIU respectively. By using this method, we can detect multiple analytes in the same sensing area simultaneously, besides that we can also effectively compensate for the errors caused by background index interference, and the refractive index change resulting from the non-specific binding, or physical absorption and others. It worth to say that by using this method, we can adjust and control the resonance wavelength by changing the fiber grinding angle, while keeping the testing sensitivity is not reduced. For practical applications, this reflective distributed fiber-based sensor is much suitable for biochemical sensing, it has small size and can enter a small testing spaces (μm scale). The diameter of the twin-core fiber is the only 125μm, which helps to be integrated into a micro-fluidic chip. In this paper, we integrate the fiber probe into an infusion needle to simulate blood vessels on-line monitoring.

A multi-channel fiber SPR sensor based on TDM technology

Surface plasmon resonance (SPR) sensor has been widely used in biochemical reaction detection. With the development of SPR sensing, multi-channel SPR sensors have attracted attention owing to their potential application in multi-analyte detection. For fiber-based SPR sensor, due to the small size of the fiber core, it is hard to realize the multi-channel fiber SPR sensor based on the time division multiplexing (TDM) technology. Here we propose and demonstrate a multi-channel fiber SPR sensor based on the TDM technology by using the multi-core fiber. The multiple cores are multiple sensing zones, which equals to subdividing the traditional single fiber core into multiple independent sensing zones, realizing the multi-channel SPR sensing. This multi-channel SPR sensor has some advantages: it can realize multi-analyte detection simultaneously; it can compensate the ambient temperature variation, nonspecific binding and physical absorption and others; it can adjust working resonance wavelength shift range by adjusting the fiber grinding angle; it can work without resonance wavelength shift range overlapping by switching independent sensing channels. Besides that, we can add a sensing zone on the receiving fiber to construct the wavelength division multiplexing (WDM) sensing for each fiber core channel. By combining TDM and WDM technology, we can double the sensing channels.

Study on Preparation and Cutting Performance of a New Diamond Grinding Fiber

A new kind of diamond fiber with a certain length to diameter ratio and macroscopic dimensions(1mm×1mm×10mm)by powder injection molding and buried sand sintering method is designed and obtained. The new diamond fiber uses the Na2O-Al2O3-B2O3-SiO2 system ceramics adding a certain amount of iron group metal Co as the diamond abrasive ceramic-metal bond. Different from the traditional diamond grits, this new kind fiber has orderly arrangement in accordance with the requirements and can prepare ordered diamond fiber grinding wheel. Then the flexural strength, hardness and other properties of the diamond fiber are measured, and the contrast test between single diamond fiber specimen and normal ceramic wheel processed ultrahard material SiC enhanced high silicon aluminum alloy is conducted. The results shows that the new diamond fiber prepared has a certain strength and hardness; ceramic-metal bond in the new fiber gives better wet-ability and stronger holding force to the diamond abrasive particle and makes it difficult to fall off; meanwhile, the new diamond fiber has good processing performance and the workpiece has good surface quality, which can achieve precise machining SiC enhanced high silicon aluminum alloy. Effective diamond abrasive particles have a high percentage in the new diamond fibers, and the distribution is uniform. The abrasive particles have a good quality of high uniformity of protrusion height, and have a high utilization with large amount of abrasive particle participated in cutting. Diamond in the diamond fibers realizes three-dimensional arrangement, which means that the lower diamond can continue to play its cutting ability when the upper abrasive loses cutting ability or falls off due to bearing greater friction and extrusion pressure.

대나무/폴리락틱산 바이오복합재료의 기계적, 열적, 충격 및 수분흡수 특성에 미치는 대나무섬유 분쇄의 영향

대나무/폴리락틱산 바이오복합재료의 기계적, 열적, 충격 및 수분흡수 특성에 미치는 대나무섬유 분쇄의 영향

Digestion of cellulose fibers in the digestive tract of wild ruminants

370 For specialized phytophagous mammals, the grinding of plant food with teeth is one of the most important conditions of its efficient digestion. Thor� ough grinding (or remastication of cud, rumination) ensures a many times higher availability of structural carbohydrates, which are abundant in vegetable food, for their fermentation by symbionts, and accelerates the passing of food through the digestive tract that improve its assimilation. The dependence of the fer� mentation rate on the size of food particles in bovine animals was experimentally demonstrated in vivo and in sacco [1]. Digestion of cellulose fibers in the diges� tive tract during their movement from the third stom� ach (omasum) to the rectum is considered to be the result of symbionts' activity, since the grinding of fibers in the rumen and reticulum mostly depends on teeth (primary mastication and rumination). In the present study, we tried to evaluate the ability

Modelling the Kinetics of Fibre Grinding during the Processing of Rubber-Fibre Composites on Milling Equipment

Modelling the Kinetics of Fibre Grinding during the Processing of Rubber-Fibre Composites on Milling Equipment

Development of diamond-like carbon fibre wheel

The first author invented a unique diamond-like carbon (DLC) grinding wheel, in which the DLC fibres were made by rolling Al sheets coated with DLC films and aligned normally to the grinding wheel surface by laminating Al sheets together with DLC fibres [K. Yamaguchi, Y. Wei, M. Takeuchi, Development of DLC fibre grinding wheel, in: Proceedings of the Vernal Meeting of the JSPE, Tokyo, 16–18 March 1999, p. 260]. In this paper, the formation process of DLC fibres and the fabrication process of a DLC fibre wheel were investigated. Many grinding experiments were also carried out on a precision NC plane milling machine using a newly developed DLC wheel. Grinding of specimens of silicon wafers, optical glasses, quartz, granites and hardened die-steel SKD11 demonstrated the capabilities to nanometer surface finish. A smooth surface with a roughness value of Ra 2.5 nm (Ry 26 nm) was achieved.