Fiber Technology Research Articles

Kinetics of manganese removal from groundwater via biological activated carbon fiber

Abstract The residual manganese concentration from groundwater treatment plants normally exceeds the limit of 0.1 mg L−1, which is the maximum permissible manganese content set by the Ministry of Health. A new biological activated carbon fiber technology is described in this paper, in which filtration columns filled with ACF and inoculated manganese oxidizing bacteria (Citrobacter sp. FM-2) were used in an attempt to effectively remove the Mn2+ in groundwater using a biological method. By researching the various factors that influence biological manganese removal, a new kinetics model of BACF filtering with multiple influencing factors that incorporates the key factors of the process, such as the temperature, pH and empty bed contact time (EBCT), was established, and the accuracy of the model was verified. The study further extends the research on biological manganese removal and provides a reference and basis for production practice to some extent.

Polarity management of multicore fiber-based optical devices in unidirectional and bidirectional spatial channel networks

Uncoupled multicore fibers (MCFs) are expected to be the first to be commercially deployed due to their high compatibility with existing single-mode fiber technologies. Since MCFs have a 3D shape, they generally exhibit connection polarity. Thus, optical devices based on MCFs also generally have polarity, which will complicate the core resource assignment and end-to-end core connections in future MCF-based spatial channel networks (SCNs). In this paper, we first discuss the polarity of MCF-based optical devices (MODs) such as MCF patch cords, spatial multiplexers (SMUXs), core selective switches (CSSs), and core selectors (CSs). We then propose a definition for global core numbers in a two-MCF unidirectional (2MCF-UD) SCN and a single-MCF bidirectional (1MCF-BD) SCN. We also propose a method for managing the polarity of MODs and correctly connecting cores end-to-end. To verify the effectiveness of the proposed global core numbering and polarity management method for MODs, testbeds emulating a 2MCF-UD SCN and a 1MCF-BD SCN are constructed using prototype CSS, CS, and SMUX devices. By using light with different optical frequencies as input and observing the output spectrum, we confirm that the spatial channel specified by the global core number is established correctly end-to-end in the SCN if the polarity of the MODs is set correctly.

Delay drift compensation of an optoelectronic oscillator over a large temperature range through continuous tuning

Phase noise reduces target sensitivity in radar and increases bit error rate in telecommunications systems. Optoelectronic oscillators are known for using optical fibre technology to realise the large delay required to attain superior phase noise performance compared to conventional microwave source technology. However, the long fibre is vulnerable to environmentally induced phase perturbations, while conventional phase shifters have insufficient range to compensate for the phase drift over the operational temperature range without the use of a temperature-controlled enclosure. Here we introduce a vector modulator controlled by a Stuart-Landau integrator, as a solution to non-efficient tuning for the phase shift. The concept is verified by simulation and experimentally demonstrated using an optoelectronic oscillator phase-locked to a system reference. Phase lock is maintained over four free spectral ranges equivalent to a tuning phase range of 1440° when the optoelectronic oscillator is cycled over a 10 °C to 85 °C temperature range. These demonstrations highlight the practical potential of our continuous tuning method.

Synthesizing gas-filled anti-resonant hollow-core fiber Raman lines enables access to the molecular fingerprint region

The synthesis of multiple narrow optical spectral lines, precisely and independently tuned across the near- to mid-infrared region, is a pivotal research area that enables selective and real-time detection of trace gas species within complex gas mixtures. However, existing methods for developing such light sources suffer from limited flexibility and very low pulse energy, particularly in the mid-infrared domain. Here, we introduce a concept that is based on the combination of an appropriate design of near-infrared fiber laser pump and cascaded configuration of gas-filled anti-resonant hollow-core fiber technology. This concept enables the synthesis of multiple independently tunable spectral lines, with >1 μJ high pulse energies and a few nanoseconds pulse width in the near- and mid-infrared regions. The number and wavelengths of the generated spectral lines can be dynamically reconfigured. A proof-of-concept laser beam synthesized of two narrow spectral lines at 3.99 µm and 4.25 µm wavelengths is demonstrated and combined with photoacoustic modality for real-time SO2 and CO2 detection. The proposed concept also constitutes a promising way for infrared multispectral microscopic imaging.

Optimising wound healing: the role of gelling fibre technology and antimicrobial silver nanoparticles.

Gelling-fibre dressings have been found to be a rapid and effective tool for exudate management. Suprasorb Liquacel Pro is a soft, conformable non-woven dressing made from sodium carboxymethyl cellulose and strengthening cellulose fibres. When it comes into contact with wound exudate or blood, the absorbent dressing forms a gel, creating a moist wound environment. Cell debris and bacteria in the exudate are retained inside the fibre dressing and removed during the dressing change. The high vertical absorption of exudate into the fibre dressing protects the wound environment and the wound edge, thus supporting the healing process. Suprasorb Liquacel Ag has additional antimicrobial abilities with the inclusion of nanosilver technology, shown to be effective in killing bacteria and managing bioburden.

Research of Optical Fiber Sensing Technology in Bridge Detection

Fiber optic sensing technology is a new type of detection technology that realizes information transmission through total reflection of light and photoelectric conversion. It has been used in the fields of medicine, military, communication, transportation, industrial control, scientific research, etc., especially in the field of bridges for decades.This paper summarizes the research status of optical fiber sensing technology and optical fiber in bridge detection, and reviews the application of optical fiber in bridge detection. First, this paper introduce the optical fiber technology, its working principle and application advantages. Secondly, the feasibility of optical fiber sensing technology in bridge detection is demonstrated through concrete application cases. It includes the detection of bridge structure and the detection of bridge material structure. Through the optical fiber sensing technology, this paper can detect the hidden dangers of the bridge in a timely and non-destructive manner Finally, this paper prospect the future development of optical fiber technology in the field of bridge detection.

Cylindrical Vector Beams with an MOPA Amplifier Based on Nonlinear Polarization Rotation Mode-Locking

CVBs (cylindrical vector beams) are widely used in optical imaging, optical trapping, material processing, etc. In this study, based on mode-selective couplers and passive mode-locking fiber technology, a cylindrical vector fiber amplifier with an MOPA (master oscillator power amplifier) structure was developed. In the experiment, the pre-amp stage reached 19.87 mW output power and a CVB output with a mode purity greater than 97%. The measured beam quality factor was M2 = 2.1. The CVB output power obtained by the first-amp stage was 152.4 mW, and the mode purity was greater than 92%. The measured beam quality factor was M2 = 1.99. The internal inhomogeneity and external effects of the isotropic LMA (large-mode-area) fiber led to a decrease in beam quality and mode purity. After amplification, the gain of the fundamental mode was higher and the power was greater, resulting in a greatly reduced mode purity. This CVB fiber amplifier yielded important research value in expanding the applications of high-power fiber lasers.

Scalable Production of Functional Fibers with Nanoscale Features for Smart Textiles.

Functional fibers, retaining nanoscale characteristics or nanomaterial properties, represent a significant advance in nanotechnology. Notably, the combination of scalable manufacturing with cutting-edge nanotechnology further expands their utility across numerous disciplines. Manufacturing kilometer-scale functional fibers with nanoscale properties are critical to the evolution of smart textiles, wearable electronics, and beyond. This review discusses their design principles, manufacturing technologies, and key advancements in the mass production of such fibers. In addition, it summarizes the current applications and state of progress in scalable fiber technologies and provides guidance for future advances in multifunctional smart textiles, by highlighting the upcoming impending demands for evolving nanotechnology. Challenges and directions requiring sustained effort are also discussed, including material selection, device design, large-scale manufacturing, and multifunctional integration. With advances in functional fibers and nanotechnology in large-scale production, wearable electronics, and smart textiles could potentially enhance human-machine interaction and healthcare applications.

Optical Fiber Technology for Efficient Daylighting and Thermal Control: A Sustainable Approach for Buildings

Different direct solar harvesting systems for daylighting are being explored to achieve high uniform illumination deep within buildings at minimal cost. A promising solution to make these systems cost-effective is the use of plastic optical fibers (POFs). However, heat-related issues with low-cost POFs need to be addressed for the widespread adoption of efficient daylighting technologies. Previous studies have explored solutions for this overheating problem, but their effectiveness remains uncertain. This study proposes a low-cost fiber optic daylighting system integrated with a newly patented mechanical component designed to secure the fiber optic bundle at the focal point, providing three levels of heat filtration while ensuring uniform illumination. Our methodology involves selecting a small area, installing the setup, and measuring both heat and light readings, followed by validation through software simulations. The operational principle of this technology is explained, and experimental tests using lux meters and infrared thermometers were conducted to investigate the system’s characteristics. The three-level heat filtration device reduces temperature by approximately 35 °C at the surface of the optical fiber, and the average illumination of the room is around 400 lux. These results were further verified using RELUX simulation software. The findings demonstrate the promising potential of this new device in solar heat filtration and achieving uniform illumination. Recommendations for mitigating overheating damage and exploring heat filtering possibilities in new parabolic solar daylighting systems for further research are also provided.

A new path planning strategy driven by geometric features and tensile properties for 3D printing of continuous fiber reinforced thermoplastic composites

Three-dimensional (3D) printing technology for continuous fiber reinforced thermoplastic composites (C-FRTP), capable of rapid manufacturing of lightweight components with intricate geometric features, has emerged as one of the most promising technologies in the field of advanced composite manufacturing. Path planning is a crucial step for determining the fabrication quality of C-FRTP components. This study proposed a new 3D printing path planning strategy driven by the geometric features and tensile properties of C-FRTP components. The strategy employed the properties of the Euler graph to generate the continuous full-field filling paths, ensuring the geometric features of the target components. The intersections were scattered along the printing path to enhance the tensile strength. The feasibility and advantages of the new path planning strategy were validated by comparative experiments with different printing paths. The results indicated that the new strategy not only achieved the geometric features of the target components but significantly enhanced their tensile strength. Using the printing path generated by the new path planning strategy, the tensile strength of specimens featuring mounting holes reached 349.4 MPa, which was only about 4.1 % lower than the tensile strength of continuous fibers at straight paths. Compared to the existing contour-parallel path, the new strategy in this work improved the tensile properties by about 40.9 %. The new path planning strategy proposed in this study shows great potential to design and fabricate C-FRTP components with enhanced mechanical properties for practical applications.

Journal of Fiber Science and Technology in the Age of Generative AI

Journal of Fiber Science and Technology in the Age of Generative AI

Optical Fiber‐Based Wearable Sensors for Remote Health Monitoring [Invited

AbstractThe wearable optical fiber sensors have demonstrated significant promise in the realm of health monitoring in recent times. These sensors utilize the flexibility and exceptional sensitivity of optical fibers to precisely measure many physiological aspects of the human body, including heart rate, breathing rate, mobility status, and body temperature. Optical fiber sensors usually have good biocompatibility and anti‐interference capabilities, can be integrated into flexible materials, and are suitable for long‐term wear. It can be integrated into clothing, patches, or accessories to provide continuous, real‐time health data monitoring, providing important support for personalized medicine and remote health management. This paper primarily presents the fundamental operating concept of wearable optical fiber sensors and their use in monitoring physiological signals across multiple domains. In conclusion, this paper provides a summary of the limitations and future prospects of wearable fiber sensors using optical fiber technology.

Photo-thermal effects initiate multi-level energy conversion in “solid-solid” phase-changing fibers

The current textiles primarily employ passive heat barriers to minimize heat loss and achieve effective thermal insulation for human beings. Accordingly, intelligent fibers with energy storage and temperature control capabilities have garnered significant attention due to their potential to revolutionize textile technology. The study integrates the photo-thermal effect and phase change energy storage materials onto a fiber, thereby fabricating a fully intelligent energy storage fiber. This innovation enables the multi-level conversion of sunlight: “Optical energy - Thermal energy - Phase transition energy - Thermal energy”. The intelligent fiber efficiently converts solar energy into heat energy through the photo-thermal coupling of CuNPs, subsequently inducing a spatial conformational change in the solid-solid phase change material within the fiber for effective heat storage. The hybrid fiber possesses enhanced mechanical properties but also exhibits a significantly high phase transition enthalpy value of 49.75 J g−1 and a phase transition temperature suitable for human body temperature (20.19–30.21 °C), especially the fiber is more durable. The photo-thermal conversion test vividly demonstrates the systematic transformation of four distinct forms of energy within the composite fiber. This approach holds significant potential for advancing the field of smart fiber technology.

Chirped grating for TE-five/TM-three reflective distribution feature

This research expounds on a novel reflective chirped grating, characterized by its differentiated functionality under various polarization modes. Under perpendicular incidence, this intricately grating produces a quintuple-channel diffraction output of the 0th, ±1st, and ±2nd orders in transverse electric (TE) polarization and a triple-channel diffraction output of the 0th and ±1st orders in transverse magnetic (TM) polarization. Both polarization modes exhibit excellent overall diffraction efficiency and uniformity. At an incident wavelength of 1550 nm, the diffraction efficiencies for the 0th, ±1st, and ±2nd orders under TE polarization are 20.16%, 19.27%, and 20.25%, respectively. Simultaneously, under TM polarization, the efficiencies for the 0th and ±1st orders are 31.79% and 31.57%, respectively. Grating parameters were meticulously derived using the finite element method (FEM) and subsequently corroborated through rigorous coupled-wave analysis (RCWA) to ensure superior grating accuracy. The study also exhaustively analyzes the manufacturing tolerances and robustness of the grating, affirming its practical applicability and effectiveness in practical applications. The dual-function grating splitter proposed in this paper enables the implementation of multiple functionalities within simple setups, suitable for applications requiring varied beam splitting. As photonic systems and fiber technology evolve, the potential applications of dual-function reflective splitters in these fields are increasingly highlighted.

Enhancing flame retardancy in 3D printed polyamide composites using directionally arranged recycled carbon fiber

Combining recycled carbon fiber (rCF) and 3D printing technology has shown great potential for fabricating functional prototypes and production parts used in the aerospace and automotive industries. However, it is still a challenge to design flame-retardant 3D printed parts with high mechanical properties and flame-retardant rating. In the work, a flame-retardant polyamide (PA)-based composite for material extrusion 3D printing was prepared by utilization of rCF, polyhedral oligomeric silsesquioxanes (POSS), and 9,10-Dihydro-9-oxa-10-phosphaphenanthrene (DOPO)-based flame retardant. The 3D-printed composites have high thermal stability, mechanical properties, and excellent flame retardancy with a V-0 rating. With the benefits of material extrusion 3D printing, directionally arranged rCF in 3D printed composites could effectively inhibit the fire spread, extend the time to ignition (TTI), reduce the total heat release (THR) and total smoke release (TSR) of 3D printed composites. The directional flame-retardant mechanism is mainly the thermal conductivity mechanism of the condensed phase and the promotion of stable ordered carbon layer formation. It provides a promising path for designing high-performance flame-retardant materials.

Early diagnosis of Chikungunya virus utilizing square core photonic crystal fiber (SC-PCF) with extremely high relative sensitivity

Chikungunya virus (CHIKV) poses a significant public health threat due to its capacity to cause widespread and debilitating outbreaks. The virus is responsible for CHIKV fever, a disease characterized by severe joint pain, sudden onset of fever, headache, muscle pain, and rash. The virus has been reported in various regions globally, with outbreaks occurring in parts of Africa, Asia, the Americas, and the Indian subcontinent. Consequently, the scientific community expends substantial efforts in developing dependable, rapid, highly sensitive, and cost-effective techniques in order to identify the CHIKV virus. In this study, an innovative biomedical sensor using photonic crystal fiber technology enables precise detection of the CHIKV virus through uric acid, normal and infected plasma, red blood cells, and platelets in the blood. The introduced sensor identifies those kinds with extremely increased relative sensitivity and minimal losses in contrast to alternative photonic crystal fiber-based biosensors. The introduced sensor showcases a minimal confinement loss of 2.25 × 10− 13 cm− 1, a relative sensitivity of 99.37%, an effective area of 1.36 × 105 µm2, with a minimal effective material loss of 0.001966 cm–1, a numerical aperture of 0.1874, and low dispersion of 0.06. Also, the demonstrated sensor is able to function within the terahertz spectrum, covering a substantial span from 0.8 to 2.6 THz. Furthermore, an extensive comparison analysis is performed between the showcased sensor and related literature on photonic crystal fibers to verify the reliability and effectiveness of the introduced structure.

A Decade of Insights: Reevaluating the Use of the Flexible-Fiber CO2 Laser in Brain Tumor Surgery-Efficacy, Challenges, and Lessons Learned.

The introduction of flexible fiber technology in the early 2000s revitalized the interest in the CO2 laser for neurosurgical applications, making it suitable for microsurgical procedures. Despite its widespread use, specific indications for the CO2 laser in neurosurgery remains undefined. This study evaluates the efficacy and limitations of the CO2 laser in brain tumor surgery. This retrospective observational single-center study analyzed the use of the CO2 laser in intracranial neoplasm surgeries from 2011 to 2021. A total of 94 patients were assessed, focusing on demographics, tumor characteristics, surgical duration, complications, and laser-specific issues. We used a five-tiered scoring system to assess laser effectiveness in both debulking and dissection tasks; with resection extent assessed following established guidelines. The CO2 laser was highly effective in debulking solid tumors, achieving a 76.5% gross total resection rate, while being less effective in softer, highly vascularized tumors. The average effectiveness scores for dissection (2.6±0.8) were significantly lower than for debulking (3.2±1.2). Two major complications were directly associated with laser use. Effectiveness improved over time, particularly in the latter half of the study, and varied across tumor types, with notable utility in meningiomas and vestibular schwannomas but lower scores in glial tumors. The CO2 laser is a valuable tool in neurosurgery, especially for solid tumors in specific anatomical locations. Careful patient selection is crucial, and the laser complements rather than replaces conventional surgical tools. Ongoing technological advancements suggest broader future applications in neurosurgery.

Research on prediction method of coal mining surface subsidence based on MMF optimization model

Coal seam mining causes fracture and movement of overlying strata in goaf, and endangers the safety of surface structures and underground pipelines. Based on the engineering geological conditions of 22,122 working face in Cuncaota No.2 Coal Mine of China Shenhua Shendong Coal Group Co., Ltd. a similar material model test of mining overburden rock was carried out. The subsidence of overburden rock was obtained through the full-section strain data of distributed optical fiber technology, and the characteristics of mining surface subsidence were studied. The Weibull model was used to adjust the mathematical form of the first half of the surface subsidence curve via the MMF function. On this basis, the prediction model of coal seam mining surface subsidence was established, and the parameters of the prediction model of surface subsidence were determined. The test results show that with the advancement of coal seam mining, the fit goodness of the surface subsidence prediction curve based on the MMF optimization model reaches 0.987. Compared with the measured values, the relative error of the surface subsidence prediction model is reduced to less than 10%. The model displays good prediction accuracy. The time required for settlement stability in the prediction model is positively correlated with parameter a and negatively correlated with parameter b. The research results can be further extended to the prediction of overburden “three zones” subsidence, and provide a scientific basis for the evaluation of surface subsidence compression potential in coal mine goaf.

Heavy metal fluoride glasses: A tutorial review

Heavy metal fluoride glasses are the backbone of modern mid-infrared fiber technology. In the last few years, optical fibers made of fluorozirconate, fluoroaluminate, and fluoroindate glasses have reached the high level of reliability that is required for their widespread use in industrial and medical applications, which explains the rapid growth of this technology. In this tutorial review, the author, who was part of the team that discovered heavy metal fluoride glasses exactly fifty years ago, provides a summary of the glass synthesis process and elucidates the most important physical properties of heavy metal fluoride glasses. Finally, a brief overview of their main application areas is presented.

Chitosan-coated iron(III) oxide nanoparticles and tungsten disulfide quantum dots-immobilized Fiber-based WaveFlex Biosensor for Staphylococcus Aureus bacterial detection in real food samples

The research proposes and investigates an extraordinarily sensitive, label-free WaveFlex biosensor utilizing optical fiber technology for the detection of Staphylococcus aureus (S. aureus), a common foodborne bacterium. The WaveFlex biosensor (plasmon Wave based Flexible optical fiber Biosensor) is based on a novel flexible tapered single-mode fiber structure, utilizing gold nanoparticles (AuNPs) to trigger the phenomenon of localized surface plasmon resonance (LSPR). Additionally, the sensitivity is further enhanced using chitosan-coated iron(III) oxide nanoparticles (Fe3O4–CS NPs) and tungsten disulfide quantum dots (WS2-QDs). The optical fiber surface is functionalized with antibodies to achieve specific detection of S. aureus. For S. aureus concentrations at 1 × 108 CFU/mL (colony-forming units per milliliter), the sensor's maximum sensitivity of 2.74 nm/lg (CFU/mL), and a detection limit (LOD) of 6.67 CFU/mL. This ultra-sensitive biosensor holds great potential for widespread applications in various fields, including disease detection, medical diagnostics, and food safety inspection.