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This laboratory analysis was done to scrutinize the compressive strength of nominal mix concrete (NMC) and fiber reinforced concrete (FRC) for M30 grade of concrete. In this study, cubes of NMC prepared by adding fly ash 20% and 30% of the weight of cement. Apart from this, the FRC mix prepared by adding steel and glass fiber in the NMC mixture. The experimental study consists of the construction of 84 cubes, out of which 36 cubes of SFRC and 36 cubes of GFRC cast for different percentages of fiber. Out of 36 cubes of SFRC, 18 cubes cast with 20% fly ash and 18 cubes cast with 30% fly ash and the same as for GFRC and 12 cubes of NMC, 6 cubes cast with 20% fly ash and 6 cubes cast with 30% fly ash. The compressive strength calculated by averaging the strength of three cubes cast for each fiber ratio. These mixes tested for its hardened property like compressive strength in this comparative study. The compressive strength tested on UTM after 7 and 28 days curing, where results show improvement in individual fibers.

The fast and high response detection of neurotoxic H2S is of great importance for the environment. In this paper, directly electrospinning technology on the ceramic tube is developed to improve the response of H2S detector based on superlong SnO2 fibers. The submillimeter continuous fibers are deposited directly on ceramic tubes by in-situ electrospinning method and can keep morphology of fibers during calcination. By employing this technology, CuO-doped SnO2 fiber H2S detectors are fabricated, and 10% atom CuO-doped SnO2 H2S detector shows the highest response of 40 toward 1 ​ppm ​H2S at 150 ​°C while the response is only 3.6 for the H2S detector prepared in traditional route. In addition, the in-situ electrospinning H2S detectors show faster response and recovery compared to the H2S detectors fabricated by the conventional way. The high and fast response of H2S detectors based on in-situ electrospinning can be ascribed to the continuous fiber structure and CuO modification. The present in-situ electrospinning technology may provide a new strategy for the development of other gas-detectors and bio-detectors with fast and high response.

Drilling muds play an important role in drilling and production operations so that the degree of success in such operations is determined by the proper design of these fluids. To optimize drilling operations and avoid excessive expenditure, it is essential to prepare a drilling mud that is both cheap and efficient. Fluid additives are typically used in drilling systems to improve these fluids' capabilities in terms of hole cleaning capacity, filtration control, viscosity, yield point, heat transfer, etc. However, environmental concerns, cost of production, and availability are always considered challenging factors. This study introduces an eco-friendly herbal fiber in powder and regular forms as a potential alternative to other chemical additives. To do so, Alyssum homolocarpum seed mucilage was added with different concentrations to the water-based drilling muds, and its rheological behavior, filtration control, and the induced formation damage were examined and the optimum concentration was introduced. The results of this study revealed the advantages of the drilling muds formulated with Alyssum in terms of filtration control, rheology, formation damage, and greenness.

Replacing micro-reinforcing fibers with carbon nanotubes (CNTs) is beneficial for improving the impact properties of ultra-high performance concrete (UHPC); however, the weak wettability and dispersibility of CNTs and the weakly bonded interface between CNTs and UHPC limit their effectiveness as composites. Therefore, this study aims to enhance the reinforcement effect of CNTs on the impact properties of UHPC via functionalization. Unlike ordinary CNTs, functionalized CNTs with carboxyl or hydroxyl groups can break the Si–O–Ca–O–Si coordination bond in the C–S–H gel and form a new network in the UHPC matrix, effectively inhibiting the dislocation slip inside UHPC matrix. Furthermore, functionalized CNTs, particularly carboxyl-functionalized CNTs, control the crystallization process and microscopic morphology of the hydration products, significantly decreasing and even eliminating the width of the aggregate–matrix interface transition zone of the UHPC. Moreover, the functionalized CNTs further decrease the attraction of the negatively charged silicate tetrahedron to Ca2+ in the C–S–H gel, while modifying the pore structure (particularly the nanoscale pore structure) of UHPC, leading to the expansion of the intermediate C–S–H layer. The changes in the microstructures of UHPC brought about by the functionalized CNTs significantly enhance its dynamic compressive strength, peak strain, impact toughness, and impact dissipation energy at strain rates of 200–800 s−1. Impact performance of UHPC containing a small amount of carboxyl-functionalized CNTs (especially the short ones) is generally better than that of UHPC containing hydroxyl-functionalized and ordinary CNTs; it is even superior to that of UHPC with a high steel fiber content.

Poly(arylene sulfide sulfone)/graphene nanoplate (PASS/GNP) composites with segregated structure based on continuous polymer fiber skeletons were fabricated by coating a thin conductive layer on the PASS fibers and then performing compression molding. The formation of a unique segregated conductive network endowed the PASS/GNP composites with high electrical conductivity and excellent electromagnetic interference (EMI) shielding effectiveness (SE), reaching 17.8 ​S/m and 30.1 ​dB, respectively, when the content of the GNPs in the conductive layer was 20 ​wt%. The PASS/GNP composites also exhibited outstanding mechanical properties, which was attributed to the continuous PASS fiber skeletons that could withstand large loads and the strong interfacial interaction between the conductive layers and the PASS fibers that could provide good stress transfer. This approach is suitable for most soluble polymers.

The analysis of microplastics (MP) becomes more difficult for smaller sizes, especially in complex matrices such as sediment of natural waters. In this work, we analyzed MPs in sediment using laser direct infrared (LDIR) imaging, a relatively new technique in environmental MP studies. Sediment samples were spiked with analytical surrogates (polyethylene spheres), and subjected to density separation, wet peroxide oxidation, calcite removal, and filtration. The extracted particles were coated on to a low-emissivity glass slide which was first examined on a stereomicroscope. Six slides (two sediment samples and four different blanks) were further analyzed using an Agilent LDIR system. Approximately 520 and 430 MP/g were found in the two samples, with diameter ranging 20–3384 μm and 84% being smaller than 100 μm. The increase in particle count with decreasing particle sizes followed a power law curve, suggesting that a large portion of the smaller MPs was generated by the breakdown of larger plastic pieces. Major polymers found in this work included polyamide, polyester, polytetrafluoroethylene, and polyacetal. Most MPs were fragments, while beads and fiber were also found. In the two sediment samples, 14% and 46% of the total particles, respectively, were composed of non-plastic micro-sized particles, including natural polyamide, cellulose, chitin, rubber, and “unknown”. Challenges, potential biases, and uncertainties are discussed. This work is the first application of LDIR imaging on MPs in natural sediment.

The emerging one-dimensional wire-shaped supercapacitors (SCs) with structural advantages of low mass/volume structural advantages hold great interests in wearable electronic engineering. Although graphene fiber (GF) has full of vigor and tremendous potentiality as promising linear electrode for wire-shaped SCs, simultaneously achieving its facile fabrication process and satisfactory electrochemical performance still remains challenging to date. Herein, two novel types of graphene hybrid fibers, namely ferroferric oxide dots (FODs)@GF and N-doped carbon polyhedrons (NCPs)@GF, have been proposed via a simple and efficient chemical reduction-induced fabrication. Synergistically coupling the electroactive units (FODs and NCPs) with conductive graphene nanosheets endows the fiber-shaped architecture with boosted electrochemical activity, high flexibility and structural integrity. The resultant FODs@GF and NCPs@GF hybrid fibers as linear electrodes both exhibit excellent electrochemical behaviors, including large volumetric specific capacitance, good rate capability, as well as favorable electrochemical kinetics in ionic liquid electrolyte. Based on such two linear electrodes and ionogel electrolyte, a high-performance wire-shaped SC is effectively assembled with ultrahigh volumetric energy density (26.9 mW·h·cm−3), volumetric power density (4900 mW·cm−3) and strong durability over 10000 cycles under straight/bending states. Furthermore, the assembled wire-shaped SC with excellent flexibility and weavability acts as efficient energy storage device for the application in wearable electronics.

The results of experiments on ablation of targets made of stainless steel and aluminum by a scanning beam of nanosecond pulses at intensity up to 109 W/cm2 are presented. It was found that the overlap of the impact zones during irradiating leads to an increase in the ablation depth in proportion to the area of overlap of the irradiation spots. This is due to increase in overlap irradiation spots degree, zones with a large number of pulse effects are formed on surface, which increases the depth of the melt bath and leads to the ejection of larger particles. An increase in ablation depth of aluminum increase with increase of the interval between pulses up to 10 ms and overlapping of the irradiation spots. The shape of the ejected particles changes from spherical, when formed from a melt, to an irregular shape, when the target is mechanically destroyed by an internal shock wave. The size and velocity distribution of the ejected particles was determined, and on the basis of these data, the laser radiation shielding coefficients were calculated depending on the degree of overlapping of the irradiation spots. It was found that the main mechanism for the decrease in the efficiency of ablation by a scanning beam of radiation is the backflow of microparticles deposited on the target surface. The analysis of the energy balance of the aluminum ablation process is carried out.

OBJETIVES: To assess the effect of various factors on laser fiber tip degradation with the Thulium Fiber Laser (Tm-fiber): fiber stripping, adjustable laser settings (energy, frequency, peak power)...

Solid-state fiber dye-sensitized solar cells (SS-FDSSCs) have been the subject of intensive attention and development in recent years. Although this field is only in its infancy, metal-organic frameworks (MOFs) are one such material that has been utilized to further improve the power conversion efficiency of solar cells. In this study, MOF-integrated DSSCs were shown to have potential in the development of solar cell devices with efficiency comparable to or better than that of conventional solar cells. The power conversion efficiency (PCE) of SS-FDSSCs was improved by embedding MOF-801 into a mesoporous-TiO2 (mp-TiO2) layer, which was used as a photoanode in SS-FDSSCs, which are inherently flexible. The PCE of the MOF-integrated SS-FDSSCs was 6.50%, which is comparable to that of the reference devices (4.19%). The MOF-801 enhanced SS-FDSSCs decreased the series resistance (Rs) value, resulting in effective electron extraction with improved short-circuit current density (JSC), while also increasing the shunt resistance (Rsh) value to prevent the recombination of photo-induced electrons. The result is an improved fill factor and, consequently, a higher value for the PCE.

We analyze the potential suitability or strength of arguments for the application of multicore optical fibers in high capacity submarine cable systems via transmission and techno-economic modeling. We consider hypothetical multicore fibers (MCFs) with 2-4 weakly coupled cores and compare capacity and cost/bit against conventional single-core fibers (SCFs). The analysis is performed in the context of a trans-Atlantic link length system and we evaluate the relative fiber performance with three different, but related, system design approaches. Two SCF coating diameters are assessed in terms of how this parameter affects the cost/bit through fiber density in submarine cables and resulting cable cost. We find that MCFs may enable higher cable capacity when fiber pair limits are imposed, but likely not at lower cost/bit unless optimistic and best case assumptions are made with respect to MCF relative fiber cost. We also find that reduced diameter SCFs can deliver much of the density and cable cost savings that motivates interest in MCF without the challenges of a new eco-system as required by MCF. However, MCF may enable the design of the largest cable capacities such as 1 Pb/s or more that might not be attainable with SCFs without significant cable changes.

This paper proposes a highly sensitive, compact, and low-cost optical fiber salinity sensor based on the Mach-Zehnder interferometer. The sensor is constructed using a single mode fiber (SMF) - no-core fiber - double-C fiber (DCF) - NCF-SMF structure, with the DCF prepared by etching the dual side-hole fiber with HF acid. The DCF's large-size exposed microfluidic channels solve the previous microstructured optical fiber's challenging liquid filling and replacement problems. Theoretical simulations and experiments demonstrate that the sensor is suitable for high-sensitivity salinity measurement. The sensor exhibits a high salinity sensitivity of -2.26 nm/‰ in the salinity range of 10‰-50‰, as demonstrated by the experimental results. Additionally, the sensor exhibits some fascinating characteristics, including high repeatability, hysteresis, reversibility, and stability.

A graphene/epoxy composite based broadband all-optical tunable fiber microcavity filter is presented. The graphene/epoxy composite based microcavity shows the excellent all-optical controlability. Since the light acts on the graphene/epoxy composite directly, the microcavity has stronger optical Kerr effect and photothermal effect induced by the optical pump. Experimental results show that its wavelength tuning range and tuning step reach 25.54 nm and 832 pm/mW, respectively. It is expected to be applied in the fields of tunable optical filters, optical communication, optical sensors, fiber lasers, and spectrum scanning.

We present the structural design and polarization-maintaining performance of solid-core anti-resonant fiber with two nested circular tubes in 3 m wavelength for the first time, to the best of our knowledge. Numerical simulation results indicated that laser fundamental mode could be obtained by filling the specially designed fiber model with materials of different refractive indices to form the completely solid configuration. We calculated the bend loss of fiber to demonstrate the preferable birefringence performance and outstanding light-confining ability. With the structural deformations from resonant tubes, the birefringence coefficient was enhanced significantly from 210-5 to 6.9310-5, which was of great importance in the polarization sensitive systems. In particular, when nested circular tubes were moved to introduce deformations, the confined loss difference in two orthogonal polarizations was calculated more than two orders of magnitude, which was the desirable result to promote the fabrication of the linear polarizer in 3 m wavelength.

Optical frequency domain reflectometry measurements in internally clad single crystal sapphire fiber have received attention in recent years due to their high temperature distributed sensing potential. As work with these fibers has proceeded, there have been some inconsistencies in the results. Deeper investigation and testing has identified two critical considerations for the proper functioning of these fibers. First, users must address the propagation of multimode light along the outer surface of the fiber. By observing the far-field image of an internally clad sapphire fiber when adding index matching fluid to the outer fiber surface, we demonstrate the effects of removing the higher order modes from these fibers. The addition of index matching fluid resulted in nearly single mode performance where multimode performance was previously observed. Second, users must address the effect that coupling the fiber to the interrogator via silica based fiber has on the internally clad sapphire fibers performance. Direct fusion splicing of silica to sapphire, as has been used in the recent work with these fibers, has a mode filtering effect which can be beneficial towards the modal behavior of the fibers. However, in this paper we demonstrate that the splicing can cause a sensing failure due to little or no low order mode light, that is useful for sensing, returning to the detector. The positive results from recent years have demonstrated that optical frequency domain reflectometry sensing performance will be successful in clad sapphire fiber; but only when the considerations described herein are addressed properly.

The traditional OFDR system requires a separate auxiliary interferometer to compensate for laser nonlinear tuning effect. In order to break through this limitation, this paper proposes a simplified OFDR system by integrating an in-fiber auxiliary interferometer before the sensing fiber. We experimentally measured the laser nonlinear tuning effect, and then verified the feasibility of the system in compensating the laser nonlinear tuning effect by both simulation and experiment. Finally, The capabilities of the distributed sensing of our proposed system was confirmed by the temperature and strain sensing experiments.

In this study, ceramic fibers are used as a filler material for glass ceramic sealant in solid oxide fuel cells to improve the thermal cycle behavior. Beside the bare glass ceramic sealant for comparison, multilayered sealants with different ceramic fiber contents are fabricated to investigate the effect of ceramic fiber quantity also. The mechanical performances of the samples are measured via tensile tests by placing them between two metallic interconnector plates after the glass formation process as well as after 1, 5 and 10 thermal cycles. The results show that the mechanical strength in general tends to decrease with increasing the ceramic filler content, which can be attributed to poor adhesion due to reduced glass ceramic composition. On the other hand, thermal cycle behavior of the samples with ceramic fibers is found to be improved at some extend. This may be due to the behavior of ceramic filler network and relatively slow crystallization with increasing the amount of the filler as proven by microstructural observations. Especially for the sample including 4 ceramic fiber interlayers each having 0.030 g ceramic fibers, the mechanical strength shows an increasing trend with the number of thermal cycles.

Nowadays, alkali titanate (ATO) fibers are attracting attention because they can provide a reinforcing as well as a functional effect. In this study, ATO fibers were synthesized by a one-step calcination route without specialized equipment and flux using a resorcinol–formaldehyde (RF) resin. Homogeneous mixing of the RF resin dissolved in water, TiO2, and an alkali source led to a uniform dispersion, and the three-dimensional polymerized RF resin formed a closely structured matrix with TiO2 and the alkali source. By carbonizing the RF resins prepared using K or Na as the alkali source, titanate fibers with lengths greater than 1 mm were formed. Growth mechanisms and crystal structures of the titanate fibers synthesized with and without the RF resin were completely different. Effects of the RF resin on the crystal structure and morphology of the titanate fibers were systematically studied by changing the calcination temperature and molar ratio of TiO2 and alkali source (Li, Na, or K). We found that the RF resin played an essential role in producing a suitable reaction field for fiber growth and controlling the morphology of titanate fibers.

The use of in-fiber core-to-cladding coupling components for thermal heating purposes has been well assessed in the last decades within the development of fiber optic devices for flow measurements and water thermal conductivity calculation. In these devices, light travelling in the fiber core is transferred into the cladding and absorbed by a metallic layer surrounding the fiber, with the consequent resistive heating generation. Here we demonstrate for the first time the use of a Turn-Around-Point (TAP) Long Period Grating (LPG) as resonant core-to-cladding light coupling mechanism for the fabrication of a highly efficient heating device based on metallic coated Fiber Bragg Grating (FBG). A properly designed TAP LPG was fabricated by means of point-to-point UV laser and spliced to a 150 nm thick Au-coated FBG. The heating efficiency characterizations of the final device were analyzed, in both air and water, by evaluating the temperature increase in the gold layer surrounding the FBG at incremental values of the injected power. Collected results confirm that the use of LPGs involving the excitation of higher order cladding modes provides an excellent transferring mechanism of the fiber core light into the cladding, which in turn guarantees very high thermal heating efficiency to the final device. Moreover, by comparing such results with the performance of other in-fiber core-to-cladding coupling components already presented in literature, it was found that the TAP LPG-based device exhibits an actuation efficiency 2.5 times greater, thus resulting the most effective and highly performing solution for energy transfer to the metallic overcoat.

Soft actuators controlled by untethered methods have aroused growing attention on account of their flexibility and controllability. Soft actuators shaped in a one-dimensional structure are highly desired in diverse practical applications. In this paper, we fabricate a new core-shell CNTs@LCE fiber soft actuator made of a liquid crystal elastomer (LCE) fiber coating with carbon nanotubes (CNTs) shell. Thanks to the outstanding photothermal conversion capacity of CNTs and remarkable thermal-contraction characteristic of LCE, the obtained core-shell CNTs@LCE fiber actuator can be controlled by near-infrared light with excellent phototropic bending to arbitrary directions, lifting loads more than 4600 times of its own weight and acting as artificial muscle to control the feature of biomimetic elbow and gripper with loads. More intriguingly, the core-shell CNTs@LCE fiber can fulfill unprecedented photo-driven phototropic locomotion including tracking the moving light source, climbing a slanted surface, and optically steering as well. The involved unique photo-driven phototropic movement mechanism has been revealed experimentally and theoretically, which is highly expected to guide the fabrication of other soft smart fiber actuators for advanced applications.

In this study, nitrogen-doped graphene quantum dots (N-GQDs) exhibiting high water solubility were produced based on the hydrothermal approach. Ethylenediamine (EDA) was used as the nitrogen dopant and microcrystalline cellulose (MCC), extracted from pineapple leaf fiber (PALF) biomass, used as the carbon source. The as-prepared N-GQDs exhibited an average size of 3.7 nm, 8-10 layers and the excitation wavelength-dependent fluorescence. It was noteworthy that controlling the pH value of the EDA solution in the hydrothermal process could change the fluorescence color of the N-GQDs, exhibiting unique green, cyan and blue light. Besides, because of the effective fluorescence quenching effect of N-GQDs by mercury (II) ions (Hg2+), the as-prepared N-GQDs were successfully employed as the efficient nanosized fluorescence sensors to selectively detect Hg2+ in aqueous solutions with the detection limit of 0.25 nM and a linear range of 0∼30 μM. The selectivity experiments indicated that as-prepared N-GQDs were specific for Hg2+ even with interference by high concentrations of other metal ions. Notably, the N-GQDs could be well adopted to determine Hg2+ in river water samples.

Fiber supercapacitors (FSCs) that fulfill the necessities of high power/energy density, flexibility, robustness, and wearing comfort are prospective power sources for portable/wearable electronics. The efforts in this field remain to exploit high performance fibrous materials with combined advantages of suitable mechanical properties, high electrical conductivity, and enhanced specific capacitance. Herein, for the first time, we incorporate expanded molybdenum diselenides (MoSe2) into graphene fibers via the assistance of ethylenediamine. The presence of MoSe2 enables the as-fabricated hybrid fiber a 2.2-fold enhancement in volumetric capacitance (148.6 F cm−3) as well as good rate performance. The assembled FSC provides a capacitance of 22.8 F cm−3, an energy density of 1.2 mWh cm−3, and a maximum power density of 314.0 mW cm−3 in addition to excellent cycle stability. Notably, the flexible and mechanically steady FSCs display excellent processability under well-controlled conditions, including weaving into the fabric, and their electrochemical properties maintain unchanged under various bending angles. Furthermore, the FSCs are connected to steadily power LED lamp, illustrating the promising possibility as future wearable energy storage devices.

The primary objective of the current investigation is to evaluate the low-velocity impact behaviour and mechanical properties of low volume fibres reinforced self-compacting concrete made with 30% GGBS as a replacement of cement with a water powder ratio of 0.3. The steel, basalt and glass fibres of length 22 and 30 mm with low volume fractions of 0.25, 0.5 and 0.75% are used for this investigation. The self-compatibility of concrete is confirmed by testing the slump flow test. The addition of fibers reinforced in the concrete decreases flow as compared without fibers reinforced conrete, flow value decreased in basalt and glass as compare to steel fiber reinforced concrete. The compressive, flexural, split tensile strength and low-velocity impact resistance, shear strength were conducted after 28 days of water curing. The experimental results show that the compressive strength is only a marginal strength improvement was observed in the steel fibre reinforce self-compacting concrete mixes. The high tensile, flexural, shear strength were observed in 30% replacement of GGBS with 0.75% of steel fibres of 30 mm length. The results of the experiments express that incorporation ratio of steel fibre reinforced concrete improves the strength, remarkably tensile, flexural and shear strength as compared with the control and other fibers reinforced concrete. A significant improvement was observed in impact energy of steel fibrous reinforced concretes as compared with the control mix of self compacting concrete. The results demonstrate that use of steel fiber is reinforced in the self compacting conrete including ground granulated blast furnance slag, the impact energy and the ductility characterstics of the self compacting fiber reinforced concrete are noticeably increased.

This study provides a review of the research on the interfacial shear strength (IFSS) of the carbon nanotube (CNT) reinforced polymer composites. The IFSS reflects the efficiency of transferring load between the reinforced fiber and its surrounding matrix, which plays a critical part in determining the characteristics of the composite. The review focuses on the experimental as well as theoretical/modeling studies of the CNT and the polymer matrix interface. The major techniques required for the measurement of the IFSS of the composites have been discussed. The methods to enhance the shear strength at the interface along with the functionalization of CNT and the advantages and disadvantages have been explained in detail. Moreover, the review presents some of the research opportunities associated with IFSS for the growth and enhancement of the mechanical properties of the CNT-reinforced polymer nanocomposites.

Recent developments in the infrastructure urged the requirement of developing concrete with high performance. This research work presents the development of sustainable High Strength Fiber Reinforced Concrete (HSFRC), and its mechanical properties such as compressive strength, tensile strength and flexural strength compared to conventional High Strength Concrete (HSC). Ordinary Portland Cement (OPC) was replaced with optimum amount of Micro-Silica (MS) and Pumice Powder (PP) by 15% and 10%. Hybrid Fibers (HF) are added in the mix of 1.5% by volume of concrete. The fibers used are Steel Fiber (SF), Poly-Propylene Fiber (PPF), Basalt Fiber (BF) and Carbon Fiber (CF). Effect of fiber and its performance are compared with conventional HSC. A concrete mix with optimum content of ingredients is desired to satisfy the strength and workability. Compressive strength of mix with HF combination of SF and PPF is found to be higher than other mixes. Mix with SF and BF exhibited higher tensile strength. Contribution of fibers was confirmed by SEM analysis.

For polymer matrix microwave composites, the agglomeration of ceramic particles at a high filling ratio will cause the microwave dielectric properties, mechanical properties and thermal conductivity of the materials to deteriorate sharply. This paper examines the reinforcement effect of LCP A950 fibers on PTFE and ZnNb2O6/PTFE composites to prevent this phenomenon. SEM, DMA, and other analysis methods showed that the incorporation of a small amount of LCP can promote the crystallization of PTFE and the mechanical strength of composites. When the volume fraction of the ZnNb2O6/PTFE/LCP three-phase is 50/45/5, the composites have a medium dielectric constant ( e r = 6.46), extremely low loss ( t a n δ = 7.54 × 10−4) and a near-zero temperature coefficient of the dielectric constant ( τ e = +2.25 ppm/°C). Under the same conditions, the linear expansion coefficient of the material is 45.4 ppm/°C, which is 30.5% lower than that before doping with LCP, and the flexural strength is 37.8 MPa, which is an increase of 17% com、pared to the previous value. The LCP-reinforced composites have excellent overall properties, but when the LCP content is too high, its reinforcement effect on the composites is gradually weakened.

Superconducting nanowire fiber mats of Bi2Sr2CaCu2O8, YBa2Cu3O7 and GdBa2Cu3O7 were fabricated using electrospinning and solution blow-spinning. Fiber mats consisting of individual nanowires with long lengths (∼100 µm) and diameters between 150 and 500 nm were obtained. Magnetic properties of the samples were measured by SQUID magnetometry. Having studied a large number of such samples, we find that only the YBCO fiber mats exhibit the paramagnetic Meissner effect (PME), whereas the other materials do not. To explain these observations, we regard the current flow through the nanowires, the distinctly different current densities and the vortex dimensionality at temperatures close to Tc.

The performance of composites reinforced with natural fibers increases depending on the nature of the fibers and the type of surface treatment applied to the fibers. To improve the interfacial properties of the naturel fibers, one of natural fibers was selected (Wood Flour (WF)) and we introduced Graphene oxide (GO). The hydrogen bonding interactions between the Wood Flour and the GO facilitate the dispersion of the latter on the surface of the fibers to gives composite fibers (WF/GO). Several characterization techniques including Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Thermogravimetric analysis (TGA) and Scanning electron microscopy (SEM) have been used to study the structural, thermal stability and morphological properties of the prepared hybrid composite. Morphological analysis revealed that the applied surface treatment of the Wood Flour (WF) was efficient where a good distribution of the GO sheets on the fiber interface is detected.

In this work, a high-resolution, self-heterodyne,RF measurement of a broad-area laser is spatially resolved using an optical fiber at a range of power levels. Three separate spatial regimes of operation are revealed as power is increased: conventional modes, spatial coherence collapse, and cavity-assisted filamentation.

Graphene fiber-based supercapacitor has aroused great interest as a flexible power source in future wearable electronics. However, the low electrochemical performance of graphene fibers (GFs) usually causes the serious limitation of use in practical applications due to the material stacking, hydrophobicity and fabrication process complexity. In this work, a facile and effective plasma-assisted strategy is put forward to increase specific surface area, tune hierarchically porous structure and promote wettability of nitrogen-doped graphene fibers (NGFs), resulting in the improvement of electrochemical performance. The supercapacitor assembled from plasma-treated NGFs shows superior capacitance (878 mF/cm2 at 0.1 mA/cm2 current density) and high energy density (19.5 μW h/cm2 at 40 mW/cm2 power density), which is 23.7% and 131.4% higher than that of NGFs and GFs, respectively. Additionally, the fiber-based supercapacitor based on plasma-treated NGFs exhibits high rate capability of 59.8% and excellent cyclic performance (95.8% retention over 10,000 cycles). These plasma-treated NGFs can be promising candidates for high-performance and flexible power sources in future wearable electronics.

Concrete is the ones with compression strongness and weakness in tension. In such a case, reinforcement to the concrete is needed. Primarily steel is utilized as reinforced material. In recent times many industrials and researchers are in the process of finding an alternative material for steel. So studies and research are conducted in the field of artificial fiber. But in this research, more focus is given on natural fiber because these fibers are naturally available. The used fiber for reinforcement is known as the SISAL Fiber [SF], considered the alternative material in mount. The chemical, physical, and structural properties of the fibers are studied in detail. Analyzing the SF showed that the reinforced composite of the sisal fiber is well-grounded in civil and rural construction structural elements. This can be utilized as an alternative to steel since steel materials are hazardous to humans as well as animals. The SF production is compared with synthetic fibers and with mineral asbestos. This sisal fiber is considered the one which is economical in production with social and economic benefit.

As a result of the rapid development of electronic devices, this study aims to manufacture concrete and cement materials to protect against electromagnetic interference. Building materials can be developed for use in advanced applications such as electromagnetic shielding and conductive concrete. In this paper, one of the industrial wastes, slag, was studied, and the effect of electric induction furnace slag on reinforced concrete mixtures with steel fibers and carbon fiber reinforced concrete was discussed. The experimental results showed the improvement of concrete mixtures with the increase of slag content. Besides, the results of slag using carbon fiber were better than those of steel fiber. The reflectivity of the m4 mixture was 47 dB, and the protection effectiveness was 7 dB.

Optical fibre tapers have recently been intensively studied for a variety of applications, including telecommunications, medical, and biochemical sensing. In this research, we fabricate photonic crystal fiber taper without collapsing air holes and describe how steering air-cladding increases the evanescent-field sensitivity of microstructure fibres. The enhancement of the microstructure fibre's performance is based on the decrease of the diameter of the fiber core to a minimal width by tapering, where a specified part power of light is directed by an evanescent field passing through the air holes in the axial cladding. The initial structure of the fiber with outer diameter of 5 μm was reduced (100, 80,60) um for improving the very limited. The guided core mode and axial air holes have a high intensity overlap at 1.55 m wavelength. Some simulation results have been achieved by using the COMSOL multiphysics program. It used to design the photonic crystal fiber large-mode area and with different taper waist diameter and find mode intensity distributions guiding of 1550 nm inside the optical crystal fiber.

Carbon nanotubes (CNTs) have exhibited immense potential for applications in biology and medicine, and once their intended purpose is fulfilled, the elimination of residual CNTs is essential to avoid negative effects. In this study, we demonstrated the effective collection and simple removal of CNTs dispersed in a suspension via thermal convection. First, a tapered fiber tip with a cone angle and end diameter of 10° and 3 μm, respectively, was fabricated via a heating and pulling method. Further, a laser beam with a power and wavelength of 100 mW and 1.55 μm, respectively, was launched into the tapered fiber tip, which was placed in a CNT suspension, resulting in the formation of a microbubble on the fiber tip. The temperature gradient on the microbubble and suspension surface induced thermal convection in the suspension, which resulted in the accumulation of CNTs on the fiber tip. The experimentally formed CNT cluster possessed a circular top surface with a diameter of 87 μm and an arched cross-section with a height of 19 μm. Furthermore, this CNT cluster was firmly attached to the fiber tip. Therefore, the removal of CNT clusters can be realized by simply removing the fiber tip from the suspension. Moreover, we simulated the thermal convection that caused CNT aggregation. The obtained results indicate that convection near the fiber tip flows toward it, which pushes the CNTs toward the fiber tip and enables their attachment to it. Further, the flow velocity is symmetrically distributed as a Gaussian function, which results in the formation of a circular top surface and arched cross-sectional profile for the CNT cluster. Our method may be applied in biomedicine for the collection and removal of nano-drug residues.

Efforts are being made by several researchers and concrete technologists towards sustainability of concrete. Researchers are working on the replacement of ordinary Portland cement either partly or fully by using mineral admixtures. Geopolymer concrete has been a relatively new development which is becoming popular over the last decade. It is prepared with mineral admixtures, coarse and fine aggregates and certain chemicals so as to undergo polymerization. In the present experimental investigation, the main aim is to develop a more efficient and stronger fiber reinforced geopolymer concrete using several mineral admixtures and fibers so as to recommend it for structural applications. Fiber reinforced geopolymer concrete mixes were produced by employing metallic fibres like steel and non-metallic fibers like glass. Four types of mineral admixtures like fly ash, ground granulated blast furnace slag, condensed silica fume, and metakaolin were mixed in several percentages to serve as the binder. Solidum hydroxide with the required molarity and sodium silicate were used as alkaline liquids for polymerization. Various combinations of fibrous geopolymer concrete mixes by incorporating steel and glass fibers were prepared separately. Specimens were prepared for all the mixes and tested after 28 days of ambient curing for mechanical properties like compression, split tension & flexure. Tests for mechanical properties were conducted on hardened specimens and conclusions are drawn on optimum combinations. From the test results it can be concluded that by reinforcing GPC with fibers strength properties and other benefits can be achieved. The results indicate that fiber reinforced geopolymer concrete may be used for structural applications.

Reduced graphene oxide (rGO)-based fibers with high electrochemical performance have recently showed great potential in the field of flexible energy storage devices. However, they still suffer from low capacitance due to the severe stacking of graphene sheets. Hybrids with nanofillers are an efficient way to improve the electrochemical performance of rGO fibers. Nevertheless, controlling the distribution of nanoparticles in the matrix is still an enormous challenge due to the strong attraction among these nanoparticles which results into agglomeration. Here, we continually prepared rGO hybrid fibers via non-liquid-crystal spinning, accompanied by chemical reduction. Manganic oxide (MnOX) nanoparticles remained well-dispersed in GO dispersion during the continuous spinning of rGO/MnOX hybrid fibers. Results showed that rGO/MnOX-20 hybrid fibers possessed the best capacitance of 123.3 F g−1 (87.6 F cm−3) and 97.1 F g−1 (68.9 F cm−3) at the current density of 0.2 A g−1, and 0.5 A g−1 respectively. Furthermore, a fiber-shaped all-solid-state supercapacitor assembly from the optimized hybrid fibers demonstrated an energy density of 2.67 mWh cm−3 (3.76 mWh g−1) at the power density of 24.76 mWh cm−3 (34.89 mWh g−1). These fiber-based devices show great potential for application in the fields of wearable electronics and energy storage devices.

The fiber acquired from the dry external covering of the coconut fiber named as “coir” has the best sturdiness among all naturally available fibers. These coir strands tend to be utilized as a support in minimal expense substantial designs especially in seismic tremor districts due to their property of durability and toughness. The present study is a laboratory investigation on determining the robustness of Coconut Fiber Reinforced Concrete (CFRC) and its behavior under high temperatures. Adopting the mix design of M20, various specimens were prepared by inclusion of coconut fibers and cured. Set of cube and cylindrical specimens were subjected to temperature 200⁰C separately and compared with control specimens to determine variation in strength. A study comparing the strength aspects of CFRC, and conventional concrete subjected to normal room and high temperatures at various ages of concrete is made.

In recent years, plastic wastes represents one of the main threats to the environment. However, the use plastic fibers in concrete could be a sustainable solution to the problem of plastic waste accumulation. Moreover, the use of fibers in the production of concrete is one attempt to remedy this brittleness and to enhance other properties such as toughness and ductility. In this study, polyethylene terephthalate (PET) fibers produced from waste plastic bottles was used in reinforced concrete RC beams. PET fibers were included in concrete at two percentages (0.5% and 1% by volume). The influence of layered distributions of PET fibers in concrete on the flexural behavior of beams was also evaluated. For each mix, three layered PET fibers RC beams were prepared. Comparison with beam containing the same PET fiber percentage (full section) was presented as well. The flexural test parameters included the determination of first cracking, the yield, and the ultimate load, in addition to the deflections related to these loads. Furthermore, failure modes, toughness, and ductility were also evaluated. The use of PET fiber concrete with a layered distribution enhanced the ultimate load considerably. Moreover, the load–deflection relationships illustrated a tendency of layered PET fibers concrete beams to exhibit further deflections before failure. The toughness capacity approximately doubled for beams reinforced with 1% PET fibers concrete in the bottom quarter, bottom half, and top half sections of layered RC beams. This impressive enhancement of the flexural toughness and ductility using the layered distribution is a promising finding that could promote this type of sustainable concrete in various structural applications.

Under high sulfur loading, high sulfur content and low electrolyte/sulfur ratio (E/S), the practical application of lithium sulfur (Li–S) batteries is seriously limited by the negative and slow kinetics of polysulfide. Here, a freestanding sulfur cathode based on nitrogen doped porous carbon fiber/vertical graphene (NF@VG) composites is proposed. Porous structure and nitrogen doping effectively enhance absorption of polysulfides through physical confinement and chemical action, while vertical graphene network greatly promotes electron transfer and boosts the catalytic conversion kinetics of polysulfides. Therefore, the as-prepared sulfur cathode exhibits an initial capacity of 738 mAh g−1, and a maintained capacity of 609 mAh g−1 after 600 cycles with only 0.029% capacity fading per cycle at 1 C rate at a sulfur loading of 7 mg cm−2. In addition, the battery displays an areal capacity of 12.8 mAh cm−2 under high sulfur loading (13 mg cm−2), high sulfur content (81.6 wt%), and low E/S (4.8 μL mg−1), indicating that the NF@VG composite fibers are highly competitive as sulfur host for Li–S batteries.

Since there is no comprehensive research of the impact resistance of fiber reinforced concrete structure, the main goal of the study was to investigate the most influential parameters for impact resistance of fiber reinforced concrete structure. For such an investigation different parameter were taken into account. For example, the parameters are fly ash, cement ratio, aggregate to binder ratio etc. In order to investigate the impact resistance, beams are created by fiber reinforced concrete and afterwards they are dropped for free fall test. During the test displacement and impact were evaluated based on different impact parameters. In order to investigate the parameters, influence on the impact resistance of the fiber reinforced concrete, neuro fuzzy logic approach was implemented since the approach is suitable for highly nonlinear systems. The neuro fuzzy models are established as predictive approach in order to solve complicated mathematical relations of the impact resistance. Finite element method procedure was performed for dataset extraction for training of neuro-fuzzy networks. Results shown that the combination of fly ash and water is the most influential combination for impact resistance (RMSE = 0.0023) and residual displacement (RMSE = 0.0073) on the fiber reinforced structure. The results could be used in practical applications for resistance loading prediction before experimental procedure.

A compact and simple double F-P interference optical fiber optic gas pressure sensor based on suspended core structure is proposed and demonstrated. The sensor is formed by splicing a section of thin-walled grapefruit photonic crystal fiber (G-PCF) with single-mode fiber (SMF). By adjusting the special fusion parameters, a short air-cavity region is formed in the G-PCF next to the splicing point with the SMF segment, and the other end of the G-PCF segment is open to the atmosphere. The output interference spectrum of the sensor comprises of two spectral parameters that have different sensitivities to temperature and gas pressure. One of them is the wideband envelope that is associated with the air-cavity and it is only sensitive to the gas pressure but insensitive to the change of ambient temperature. This property is particularly useful for addressing the complex temperature-pressure cross sensitivity of both spectral parameters. The research findings indicate that the sensor can perform an accurate measurement for gas pressure in dynamic range of 0-1.0 MPa under the high temperature condition up to 500 °C.

The central pull-out tests were performed on C60 steel-fiber high-strength recycled concrete (SFHSRC) under the monotonic load. The failure mode characteristic of the specimens and the direction of the cracks were observed and described. The bond strength and slip displacement were measured. The effects of two parameters, replacement ratio of recycled coarse aggregate (RCA) and addition ratio of steel fiber, on failure mode and bond-slip mechanicals behaviors of SFHSRC were also analyzed. The experimental results showed that when the replacement ratio of RCA was kept unchanged, the slip displacement of rebar increased with the increase of addition ratio of steel fiber, but the bond strength increased first and then decreased; with the addition ratio of steel fiber was remained unchanged, the bond strength and slip displacement of rebar decreased with the increased of the replacement ratio of RCA. The bond strength and slip displacement mentioned above reached the maximum when the steel fiber addition ratio was 0.8%; that is, when the replacement ratio of RCA was 0 and the addition ratio of steel fiber was 0.8%, the bond strength reached the maximum. Based on the theoretical analysis of experimental data, a reasonable bond-slip constitutive model was established in this paper, which can help promote more extensive application of RAC and realize persistent development strategy of building, resources and environment to a certain extent.

The normal grouting material which has been widely used in traditional grouted sleeve connections has high brittleness and it often burst when broken. Moreover, these grouted sleeve connections required larger anchorage length and exhibited a worse cyclic load capacity than the steel bar. In this research, three kinds of fibers, including polypropylene fiber, polyvinyl alcohol fiber and basalt fiber, were selected as mixing materials in the grouting material. Their performance was tested in three areas: basic mechanical properties, toughness, and the optimal content and length of each fiber. Then, a total of 120 grouted sleeve connections with three selected optimal fiber grouting materials and five different anchorage lengths were manufactured. The mechanical performance of the grouted sleeves connections was tested under two loading schemes: cyclic loading at high stress (CH) and cyclic loading at large strain (CL). The compression test results of grouting materials demonstrated that fiber was an ideal material for improving the toughness of the grouting material. The optimal content of each fiber in grouting material was 0.5% (PP), 0.3% (BF) and 0.1% (PVA) and the optimal length was 9 mm (PP), 3 mm (BF) and 3 mm (PVA), respectively. Meanwhile, the minimum anchorage length of rebar in the grouted sleeves could be reduced by at least 1 d (d: diameter of rebar) when the fiber reinforced grouting material was adopted. According to the load–deflection curves under cyclic loading, the fiber reinforced grouted sleeve connections exhibited better residual deformation and stiffness degradation. Test results demonstrated that the fiber could clearly enhance the residual bond strength and ductility of the reinforced section, and the residual bond strength of the connections with the fiber grouting material could be increased by 3.8% ~ 22.8% when the steel bar was pulled out.

This study aimed to investigate the effects of reinforcement ratio on flexural behavior of I-shaped Ultra High Performance Fiber Reinforced Concrete (UHPFRC) beams. In this framework, the total of four full-scale test beams with different reinforcement ratios were cast using a UHPFRC mixture consisting of high strength steel fibers and were tested under four-point flexural loading. The flexural behavior was evaluated in terms of load-midspan deflection relationship, deflection ductility, load carrying capacity, failure mode and cracking pattern. Additionally, the experimental results of this study were compared with another research on UHPFRC beams to examine the effects of different fiber type on flexural behavior. In the beams with short steel fiber, while the amount of reinforcement slightly increased the initial stiffness, the load carrying capacity was significantly improved with the increase in reinforcement ratio. In addition, an increase in the reinforcement ratio led to an apparent increasing trend in the deflection ductility. The fiber type comparisons showed that short straight fibers are more efficient than hooked fibers in preventing inclined cracks as well as the improving load capacity.

We examine moderate CO2 laser heating as a method of forming negative effective radius variations in conventional optical fiber. Fiber samples were subjected to focused CO2 laser radiation in the form of 100 ms pulses with power 0.36 to 1.3 W and thermalization time up to 2.2 s. Fiber temperatures reached 200 to 300 degrees Celsius in each pulse. The temper atures are significantly smaller than the glass transformation temperature, which is nearly 1500 °C. We show that short CO2 laser pulses may introduce negative variations up to 5 nm. The magnitude of the introduced variation increases roughly linearly for up to 6 pulses, and then fiber saturation is achieved. We reveal that it is possible to produce optical whispering gallery modes resonators in low-temperature heating mode and create a triangular-shape microresonator solely with the negative variations. The negative variations may also occur in peripheral areas of high-temperature heated fiber while introducing positive effective radius variations. To eliminate it, we propose low-temperature fiber annealing before high-temperature variations introducing. The negative variations may also be implemented to develop a new independent approach of shaping optical whispering gallery modes microresonators.

Carbon fibers going through stabilization, carbonization, and graphitization heat-treatment stages will form continuous graphitic layers that are closely packed and preferentially aligned along the fiber axis, forming high mechanical stiffness or strength and electrical or thermal conductivity. The alignment of noncontinuous, powder-like graphene layers in polymers has been challenging due to the low bending modulus of a few- or even single-layered graphene, which causes aggregations or folding behaviors. This research demonstrates the leveraging of polymer-nanoparticle interactions to align graphene nanoplatelets (GNPs) in the polyacrylonitrile (PAN) matrix. An in-house designed spinning method produces a three-layered fiber that utilizes the interfacial interactions between each layer for graphene alignment between graphitic layers. This composite containing oriented GNPs significantly improves modulus (i.e., 42.3 to 74.6 GPa) and increases electrical conductivity for enhancing volatile organic compounds (VOCs) sensing behaviors. This research opens up a new scalable fabrication method for multilayered composites.

This paper presents the results of a research program conducted on the structural behavior of fiber-reinforced concrete columns subjected to elevated temperatures (27 °C, 200 °C, 400 °C, and 800 °C). For this purpose, three groups of reinforced concrete columns were fabricated, and a comparative study has been done on the strength properties under axial load without and with (mono and hybrid) fibers of various types (microsteel, Polypropylene, and Sisal fibers) with a constant volume fraction of 1%. The properties evaluated were the load carrying capacity, load–deflection characteristics, and failure pattern of columns, and the results were compared with the control column without fiber. The experimental study reveals that the columns reinforced with mono microsteel fiber performed well in comparison with the columns with fibers in terms of superior load carrying capacity, ultimate deflection, energy absorption capacity, ductility characteristics, and thermal resistance. Whereas the columns with hybrid fibers did not show any signs of spalling and performed functionally better than the columns without fibers. The addition of sisal, microsteel, and polypropylene fibers in hybrid form provides better fire resistance, strength, and spalling resistance compared to cement concrete columns without fiber.

We here propose and demonstrate a novel “2-in-1” fiber consisting of two freely separated fiber ends and one fiber tip mounted with nanodiamonds (NDs) containing nitrogen vacancy (NV) centers. The fiber tip with ball lens is fabricated by fusing two parallel multimode fiber with arcing discharge. The excitation and collection of the integrated NV centers through the two fiber ends, can be optimized by manipulating the fabricated lens. We also demonstrate the feasibility of all-optical thermometry using this device. This endoscopy-like probe paves the way for developing fiber-based quantum device for flexible thermometry and magnetometry.

Vulcanized fibers are all-cellulose materials made from cotton and/or wood cellulose after aqueous zinc chloride treatment. These materials were invented in the UK in the mid-nineteenth century and is widely used because of their excellent characteristics, such as impact resistance and electrical insulation. Recently the matured vulcanized fibers have been recognized as renewable and biodegradable materials and reevaluated with advanced cellulose technologies derived from cellulose nanofibers (CNFs) and all-cellulose composites. The microscopic analysis based on the improved freeze-drying method revealed that the strength of vulcanized fiber sheets can be attributed to the chemically defibrillated CNFs. The architecture is similar to all-cellulose composites made from the same raw materials in which the residual cellulose fibers serve as reinforcement, and the CNFs serve as adhesives or matrix components. In this report, we describe the history and structural characteristics of vulcanized fibers and introduce a new aspect in aqueous zinc chloride treatment of cellulose.