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In view of the problems of low added value of products, lack of innovation ability and weak brand influence, the advantages and challenges of Gaoyang county textile industry cluster were discussed by combining qualitative and quantitative analysis methods, and corresponding suggestions were put forward. The research reveals that despite Gaoyang county's outstanding performance in industrial heritage, scale a advantages, and product diversification, its development is constrained by insufficient technological innovation, weak brand building, and low level of digitization. Therefore, strategies are proposed including shifting development modes, strengthening brand cultivation, enhancing digitization levels, and promoting green production. These strategic recommendations provide valuable insights for enhancing the competitiveness of Gaoyang county and similar textile industry clusters, holding significant implications for promoting local economic development. [ABSTRACT FROM AUTHOR]

As the closest transiting hot Jupiter to Earth, HD 189733b has been the benchmark planet for atmospheric characterization1–3. It has also been the anchor point for much of our theoretical understanding of exoplanet atmospheres from composition4, chemistry5,6, aerosols7 to atmospheric dynamics8, escape9 and modelling techniques10,11. Previous studies of HD 189733b have detected carbon and oxygen-bearing molecules H2O and CO (refs. 12,13) in the atmosphere. The presence of CO2 and CH4 has been claimed14,15 but later disputed12,16,17. The inferred metallicity based on these measurements, a key parameter in tracing planet formation locations18, varies from depletion19,20 to enhancement21,22, hindered by limited wavelength coverage and precision of the observations. Here we report detections of H2O (13.4σ), CO2 (11.2σ), CO (5σ) and H2S (4.5σ) in the transmission spectrum (2.4–5.0 μm) of HD 189733b. With an equilibrium temperature of about 1,200 K, H2O, CO and H2S are the main reservoirs for oxygen, carbon and sulfur. Based on the measured abundances of these three main volatile elements, we infer an atmospheric metallicity of three to five times stellar. The upper limit on the methane abundance at 5σ is 0.1 ppm, which indicates a low carbon-to-oxygen ratio (<0.2), suggesting formation through the accretion of water-rich icy planetesimals. The low oxygen-to-sulfur and carbon-to-sulfur ratios also support the planetesimal accretion formation pathway23.The exoplanet HD 189733b has a metal-enriched atmosphere with the possible presence of H2O (13.4σ), CO2 (11.2σ), CO (5σ) and H2S (4.5σ). [ABSTRACT FROM AUTHOR]

Ramie composites have been widely used in automobiles, daily necessities, aerospace, ships, cruise lines, etc., but their flame retardant properties are relatively poor, which is difficult to meet the flame retardant performance requirements of composites for rail transit. In order to improve the properties of ramie reinforced composites, flame retardant treatment is necessary. In this paper, phosphorus flame retardant phytic acid (PA) was used to modify ramie fabric, and then the composites were prepared. The flame retardancy and mechanical properties of ramie reinforced composites were investigated. It was found that the flame retardancy of ramie composites was improved after flame retardant modification with phytic acid, but the mechanical properties were decreased. In order to improve the mechanical properties of PA ramie composites, two kinds of layered PA ramie/glass fiber hybrid composites were prepared by replacing part of ramie with glass fiber. The results show that the addition of glass fiber can improve the mechanical properties and flame retardancy of composites. [ABSTRACT FROM AUTHOR]

Enhancing the thermal-wet comfort of garments is a key factor in sportswear research. In this study, we designed a new three-dimensional moisture conduction structure model, developed double-sided fabrics of a changed spacer weft-knitted structure, and compared them with single-sided plain stitch and cellular structure fabrics, focusing on the morphology, basic structural parameters and absorption, and quick-drying performance. The findings indicated that the changed spacer weft-knitted fabric consisting of 18 tex Tencel and 33.3 tex (96 f) recycled polyester filament has a smaller surface density and thickness, the water absorption of 436%, the water evaporation rate of 0.354 g/h, and the water vapor transmission of 7476.75 g/(m2 · d). Compared with other fabrics, it has excellent absorption and quick-drying performance. Partitioned T-shirts were designed by using the human body sweating law, and four fabrics were applied to one to four areas according to the sweating degree. Through infrared image monitoring and subjective evaluation, we concluded that the partitioned T-shirt has efficient absorption and quick-drying ability, and has potential to be applied to the development of thermal-wet comfort sportswear. [ABSTRACT FROM AUTHOR]

Quality characteristics of blended yarns, which play an important role in textile quality, are continually assessed by softness, breaking strength, breaking elongation, hairiness, irregularity, etc. In this study, hemp was softened and blended with other cellulose fibers with better softness to produce yarns. The softness of hemp is obviously lower than that of the other two fibers. With the increase of hemp fiber percentage content, the yarn properties deteriorated. Therefore, the softening treatment of hemp fiber is very necessary. Moreover, the blending hemp, cotton, and viscose in the yarn structure provided synergies, improving the weak properties of ternary fibers. Results show that softening treatment and lower percentage content of the hemp fiber will result in better yarn quality, which is consistent with the derivation result of the bending theoretical model. When the percentage content of treated hemp is 40 wt%, the overall performance of blended yarn is the best. Compared with the untreated hemp-based ternary blended yarns, the hairiness of blended yarn is significantly less (3.65 ends/m, compared to 12.23 ends/m), and the irregularity of yarn is lower (27.33% and 27.70%, respectively), yarn quality improved considerably. In addition, the resulting hemp yarn showed antibacterial activity against Escherichia coli and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

In recent years, the rapid monitoring of total organic carbon (TOC) in natural waters has attracted increasing attention. Optical methods are a valid tool for measurement. Nevertheless, how to more accurately establish the mapping relationship between spectroscopy and TOC concentrations is currently a challenge. A new method based on UV-VIS spectroscopy with a deep convolutional network is proposed for the quantification of TOC in water in this paper. The Inception network, originally used to process two-dimensional image data, was redesigned as a model capable of processing one-dimensional spectral data, while the convolution and pooling scale were modified to adapt to one-dimensional data. Simultaneously, squeeze and extraction (SE) blocks were applied to the designed network to enhance feature information and to suppress interference from useless information in the regression process. The method was tested on samples collected from the sea and river estuaries in several provinces in China. When compared to the classical least squares support vector machine (LSSVM), the experimental results showed that the proposed 1D-Inception network structure can provide more accurate regression results. The SE block can significantly improve the feature extraction and expression capabilities of the 1D-Inception network structure and suppress redundant information, thereby achieving better model performance. [ABSTRACT FROM AUTHOR]

A temperature and strain dual-parameter sensor based on conical four-core fiber (FCF) combined with multimode fiber (MMF) is presented. A sensor based on Mach–Zehnder interferometry is prepared by using single-mode fiber (SMF)–MMF–FCF–SMF and tapering at the fusion point between FCF and SMF. When the temperature and strain change, the length and refractive index of the fiber change due to thermal and elastic effects. Based on the corresponding function relationship and coefficient matrix method, the temperature and strain dual-parameter matrix equation of the sensor can be obtained. The results show that the red shift of the transmission spectrum occurs with the increase of temperature in the range of 40 °C–90 °C, and the maximum temperature sensitivity is 85.45 pm/°C. At the strain range of 0– $800~\mu \varepsilon $ , the blue shift occurs in the transmission spectrum with the increase of the strain, and the maximum strain sensitivity is −6.76 pm/ $\mu \varepsilon $. Finally, the matrix equation of the dual-parameter sensor is obtained based on the experimental results. The sensor is simple to make and has high sensitivity. It can measure the temperature and strain parameters in the environment of the micro-magnetic field and micro-electric field. [ABSTRACT FROM AUTHOR]

In this article, a fiber optic sensor based on double-cladding fiber (DCF) composite tapered structure cascaded long-period fiber gratings (LPFGs) for measuring refractive index (RI), temperature, and axial strain is designed. The two ends of a Section of DCF are, respectively, fused with single-mode fiber (SMF) and LPFG1 to form two up-tapers, and then the DCF is formed into a down-taper. Another end of LPFG1 is cascaded with LPFG2, and the center wavelengths of the two LPFGs are different. LPFG1, LPFG2, and tapered DCF generate three resonance peaks, namely, dip1, dip2, and dip3, respectively, whose sensitivity in response to different parameters is different. When external parameters change, the dips will have spectral shifts. The experimental results indicate that, when the RI is changed within 1.3355–1.3715, the sensitivity of dip1, dip2, and dip3 is –52.12, – 132.58, and 37.61 nm/RIU, respectively. When the temperature varies from 30 °C to 80 °C, the sensitivity of dip1, dip2, and dip3 is 74.05, 98.02, and 26.33 pm/°C in turn, respectively. When the axial sensitivity of dip1, dip2, and dip3 is – 1.95, – 2.58, and –3.24 pm/ $\mu \varepsilon $ , respectively. The resolutions for RI, temperature, and axial strain are 0.0005 RIU, 1.3375 °C, and $14.0886 \mu \varepsilon $ , respectively. The three parameters can be monitored simultaneously using the coefficient sensitivity matrix. The designed sensor has high repeatability and good linearity, and it is practical in the field of multiparameter detection. [ABSTRACT FROM AUTHOR]

A multi-parameter sensor based on dumbbell-shaped double-cladding fiber (DCF) structure cascaded long period fiber grating (LPFG) is proposed and fabricated. It is formed by discharging between single mode fiber (SMF) and DCF to form a waist-enlarged taper and then cascading two LPFGs. When the fiber is affected by the thermal expansion effect, thermo-optic effect and elasto-optic effect, the resonant peaks formed by inter-mode interference will shift, and the shifts generated by different resonant peaks are also different. By demodulating the wavelength shift of the three resonant peaks, the temperature, refractive index and axial strain can be measured by using the coefficient sensitivity matrix. The experimental results show that the temperature sensitivity of the three resonance peaks is 14.79 pm/°C, 69.07 pm/°C and 89.83 pm/°C in the range of 25 °C~80 °C. The refractive index sensitivities of three resonance peaks are 14.27 nm/RIU, −71.39 nm/RIU and −141.07nm/RIU in the range of 1.3355 ~ 1.3715. The axial strain sensitivities of three resonance peaks are −2.26 pm/ $\mu \varepsilon $ , −2.5pm/ $\mu \varepsilon $ and −3.14 pm/ $\mu \varepsilon $ in the range of $75 \mu \varepsilon $ ~ $525 \mu \varepsilon $. The corresponding resolutions are 0.6905 °C, 0.00054RIU and $36.323 \mu \varepsilon $ , respectively. The sensor is simple and has good linearity. It can be widely used in environmental monitoring for different parameter. [ABSTRACT FROM AUTHOR]

An omni-azimuth angle sensor for tilt measuring based on fiber Bragg grating (FBG) array is proposed. It is designed based on the sensitivity of FBG to axial traction. The sensor consists of a mass block and a cube frame connected by an FBG array. The FBG array consists of four FBGs. When the sensor is tilted at different angles, the axial traction of each FBG will change due to the pull of the mass block. The tilt angle of the sensing unit can be obtained by calculating the magnitude and direction of the resultant traction of the four FBGs. The array design and measurement theory of the sensor are introduced, and the sensitivity of the sensor is discussed. Experimental results show that the FBG array can be used to measure the omni-azimuth angle. The angle sensitivity varies unevenly with the tilt angle and the range of variation is 0.08 nm/° to 0.4593 nm/°. Using the spectrometer with an accuracy of 0.01 nm, the angle resolution ranges from 0.125° to 0.0218°. The array effectively extends the measurement range of the tilt sensor, and reduces the number of FBGs as much as possible on the basis of achieving omni-azimuth angle measurement. [ABSTRACT FROM AUTHOR]

A refractive index insensitive triple cladding quartz specialty fiber temperature sensor with D-type microcavity structure is proposed. It consists of a triple cladding quartz specialty fiber(TCQSF) with a D-type microcavity structure fused between two sections of single-mode fiber(SMF). Because the SMF and TCQSF mode fields do not match, the excited modes form a Mach-Zehnder(M-Z) interferometer, resulting in a mode interference phenomenon. Experimental results show that in the range of 30-90°C, the transmission spectrum has a red shift phenomenon, the temperature sensitivity is 138.03 pm/°C, and the wavelength shift has a good linear relationship with temperature change. When the external refractive index changes in the range of 1.3350-1.3466, the sensor has a low sensitivity to the refractive index, which can avoid the cross-sensitivity of simultaneous measurement of temperature and refractive index. The sensor is not only simple to fabricate and high in sensitivity, but also has good repeatability and stable response, and has wide application prospects in the field of sensing. [ABSTRACT FROM AUTHOR]

A multi-azimuth angle sensor for tilt measuring based on long period fiber grating (LPFG) array is proposed. It is designed based on the sensitivity of LPFG to refractive index. The sensor consists of a sealed cylindrical device containing a half volume NaCl solution. The LPFG array which consists of four mutually perpendicular LPFGs is fixed in the container. When the sensor is tilted at different angles, the liquid level intersects with the LPFGs at different positions. By calculating the intersection point of liquid level and LPFGs, the liquid level equation after tilt can be obtained, and the tilt angle can be obtained. The array design and measurement theory of the sensor is presented, and the sensitivity of the sensor is discussed. The experimental result shows that the LPFG array can be used to measure multi-azimuth angle in tilt. The angle sensitivity varies unevenly with the tilt angle, and the range of variation is 0.0006nm/° ~ 0.0434 nm/°. The array expands the measurement range of the tilt angle sensor effectively. [ABSTRACT FROM AUTHOR]

A few mode fiber temperature sensor filled with PDMS based on vernier effect is proposed. It uses single mode fiber (SMF), few mode fiber (FMF), and polydimethylsiloxane (PDMS) to form the SMF-air microcavity-FMF-PDMS-FMF structure. It is to slot the glass capillary tube, place the two FMFs in the slot at a suitable distance, and fill the slot with PDMS multiple times and seal it. The PDMS is used as a sensing microcavity. We insert the SMF from the other end of the glass capillary tube, adjust the distance, fix the SMF and seal the connection. Two end faces of the SMF and the first FMF form an air reference microcavity. Since the refractive index of each medium is different, multiple reflective surfaces are formed to reflect. Because the second FMF is infinitely long, whose right end is beveled, it is considered that the sensor has four reflected beams. When the temperature changes, the length and refractive index of the PDMS microcavity will change, which will cause a change in the interference spectrum of the sensor. And because the vernier effect is formed by the superposition of the two microcavities, the temperature sensitivity can be amplified and the temperature can be measured with high sensitivity. The experimental results show that in the range of 40–56°C, the transmission spectrum of the sensor appears red shift with the increase of temperature, and the temperature sensitivity can reach 3.89nm/°C. The sensor is simple to manufacture, has high sensitivity, and has good application prospects. [ABSTRACT FROM AUTHOR]

In this paper, an Ag nanoparticles (AgNPs) modified multimode fiber (MMF) SERS probe prepared based on sol self-assembly method is proposed and fabricated. Different fiber SERS probes (AgNPs-MMF-x, x is the self-assembly time) are obtained by adjusting the self-assembly time. Using rhodamine 6G (R6G) solution as the probe molecule, the far-end performances of the prepared fiber SERS probe are studied, and the AgNPs-MMF-30 probe with obvious advantages in SERS performance is obtained. The limit of detection (LOD) for R6G is as low as 10−9 M, demonstrating the high sensitivity of AgNPs-MMF-30 probe. The enhancement factor (EF) of AgNPs-MMF-30 probe to 10−7 M R6G is about 1.36 × 108. In addition, the AgNPs-MMF-30 probe has an outstanding reproducibility across the entire area with the maximum value of relative standard deviation (RSD) of less than 10.94%. The AgNPs-MMF-30 probe exhibit a long-term stability regarding Raman enhancement of up to 35 days. Importantly, the high-performance AgNPs-MMF-30 probe is further applied as a highly sensitive SERS platform for the trace detection of antibiotic in milk. The fiber SERS probe has the characteristics of fast, effective, remote real-time detection and so on, so it has great potential application in biochemical sensing and food security. [ABSTRACT FROM AUTHOR]

An all-optical modulator based on graphene-photonic crystal fiber (G-PCF) is demonstrated, where the G-PCF is fabricated by directly growing graphene onto inner hole walls of the PCF with atmospheric pressure chemical vapor deposition. A 1550 nm pump laser is used to induce all-optical intensity modulation of probe light. A G-PCF with a length of 2 cm achieves a significant modulation depth of 2.58 dB under a low pump power of 60 mW at wavelength of 895 nm. The flexible structure and all-optical control enable the G-PCF to have great potential in all-optical devices and photonics. [ABSTRACT FROM AUTHOR]

In this paper, a corroded photonic crystal fiber (PCF) sensor is presented on the basis of core-offset splicing and waist-enlarged fiber taper corroded by hydrofluoric acid (HF). The Mach-Zehnder interference theory is used to analyze the relationship between transmission spectrum and strain. The final results obtained from experiments show that the strain sensor’s sensitivity is about −6.57 pm/με and the linearity is 0.99962 within the range of 0~1000 με, while the sensor is corroded by HF for 35 minutes at room temperature. In the temperature range of 20°C~80°C, the sensor’s sensitivity to temperature is only 1.63 pm/°C, which is insensitive to temperature. Because of its advantage compared to traditional optical fiber sensors, this sensor can avert the cross-sensitive problem when temperature and strain are measured together and has some other advantages including easily fabricated, simple structure and accurate sensitivity. It can be used in many fields, such as industrial production, monitoring, and aerospace. [ABSTRACT FROM AUTHOR]

A temperature insensitive vector curvature sensor of photonic crystal fiber (PCF) is presented based on core-offset splicing and waist-enlarged fiber taper. Obvious red and blue shifts in transmission spectrum appear at two symmetrical bending directions with sensor length of 10, 13, 16, and 19 mm and vector curvature of 0.12–1.06 m–1. The longer the sensor length is, the larger the curvature sensitivity is. The corresponding sensitivity with concave bending and convex bending are increased on average by 0.44 and 0.43 nm/m–1, respectively, while the sensor length increases per 1 mm. Moreover, when sensor length is 16 mm, the temperature sensitivity is only 1.73 pm/°C in 20–90 °C; therefore, it has the temperature insensitive property. Obviously, the reported sensor could avert cross-sensitivity of temperature and curvature when measured together. It is prospective being used in industrial production, building monitoring, aerospace, and other fields in view of its easy fabrication, simple structure, and high sensitivity. [ABSTRACT FROM PUBLISHER]

Based on the intermittent cooling method, a fused tapered Photonic Crystal Fiber (PCF) interferometer is proposed. In the process of tapering, stop heating and wait for cooling at different taper length. Repeat heating and cooling, until taper goes to the expected length. Compared with the ordinary fused tapered method, the fringe contrast of the transmission spectra of this sensor is 15.06 dB. The transmission spectra in different concentrations of glycerol solution are obtained, and the temperature cross-sensitivity of the sensor is studied. The experimental results show that as the external refractive index increases, the transmission spectra of the sensor shift to longer wavelength. In the measuring glycerol solution, the refractive index sensitivity of the sensor can achieve 797.674 nm/RIU, and the temperature sensitivity is only 0.00125 nm/°C. [ABSTRACT FROM AUTHOR]