Search

A broadband core shift photonic crystal fiber (PCF) polarization filter based on surface plasmon resonance is proposed in this paper. The fiber is consisted of an asymmetric hexagonal lattice of holes in which a small air hole is coated with gold film and another one large air hole destroyed the structure around the core. The loss of y-polarized core mode is 2232.61 dB/cm at the communication wavelength of 1.55 μm, however, the loss of x-polarized core mode is very weak. When the PCF length is 300 μm, the bandwidth of exceeding 420 nm with extinction ratio better than −20 dB is achieved. To our best knowledge, the bandwidth is the widest. As a consequence, this special fiber filter has a wider range of applications. [ABSTRACT FROM AUTHOR]

A square structure of dual communication band single polarizing plasma photonic crystal fiber filter is presented in this paper. The resonance point can be adjusted to the communication band by optimizing the parameters of fiber structure. High birefringence can be produced by changing the refractive index of the filled liquid, the thickness of the metal film, and the diameter of the air holes near the core. Numerical simulation results demonstrate that the resonance strength of x - and y -polarized direction can simultaneously reach 781.87 and 463.04 dB cm −1 at the communication wavelength of 1.31 and 1.55 μm. By filling liquid analyte the confinement loss of x - and y -polarized direction can simultaneously reach 804.71 and 451.69 dB cm −1 at the wavelength of 1.31 and 1.55 μm. Furthermore, when the fiber length of L is equal to 700 μm, the peak value of the crosstalk can reach 474.63 and −243.61 dB at the same time at the wavelength of 1.31 and 1.55 μm, and when the length of the fiber L is 400 μm, the bandwidths of the crosstalk better than 20 dB and less than −20 dB are about 160 and 220 nm, respectively. These features make it an ideal candidate for the design of a dual band polarization filter device. [ABSTRACT FROM AUTHOR]

In this paper, a photonic crystal fiber with the gold layer is simulated by finite element method. Due to birefringence, surface plasmon resonance only occurs in the y-polarization direction. The loss of y-polarization mode is much larger than that of x-polarization mode. The photonic crystal fiber is suitable for the polarization filter. The polarization filter has the short length and high extinction ratio. Furthermore, the insertion loss of the x-polarization mode is only 0.07 dB, which is the smallest as far as we know. [ABSTRACT FROM AUTHOR]

An FEM (Finite Element Method) numerical approach of predicting the effective thermal conductivities of plain woven composites is presented in this paper. Three reducing-size unit cells are formulated by using different symmetries exhibited in the composite, including translational, reflectional and rotational symmetries. Corresponding thermal boundary conditions are derived and validated by the numerical results of the same problem of different unit cells. Thermal conductivities of the matrix with porosity and the woven yarns are calculated first, and then used as input data to numerically predict the effective thermal conductivities of plain woven composite. The influences of porosity and fiber volume fraction on effective thermal conductivities of studied composites are clarified. [ABSTRACT FROM AUTHOR]

A new chitosanase gene of glycoside hydrolase (GH) family 75, csnw2 , was cloned from an isolated strain Aspergillus sp. W-2 (CGMCC7018). The mature CsnW2 protein, fused to His-tag at C-terminus, was expressed in Pichia pastoris X-33 and purified with the affinity chromatography of Ni 2+ -NTA. The novel recombinant CsnW2 showed maximal activity with chitosan at pH 6.0 and 55 °C. Moreover, it had good pH stability and thermostability at a broad pH range of 3.0–10.0 and a temperature range of 30–70 °C, respectively. The enzymatic activity of the CsnW2 could be significantly enhanced by Ca 2+ , Mn 2+ and Mg 2+ at a concentration of 1 mM, but strongly inhibited by Fe 2+ , Zn 2+ , Ge 2+ , Ni 2+ and Cu 2+ above 1 mM. The CsnW2 showed specific hydrolytic activity against chitosan and preferred to hydrolyze chitosan with high degree of deacetylation. The main products of chtiosan (92% deacetylation) were chitosan oligosaccharides (COS) with degree of polymerization (DP) arranging from 2 to 6. Combined with the hydrolysis of COS from DP2 to DP6, CsnW2 was considered to be an endo-acting chitosanase. [ABSTRACT FROM AUTHOR]

This paper presents a method of fabricating photonic crystal fiber by secondary drawing technology combined with air pressure regulation. The internal structure of optical fiber is solidified and shaped by primary drawing. The core diameter of PCF is reduced to less than 4 μ m by adding glass sleeve in secondary drawing. Multi-core PCF is prepared, and the curvature and temperature of two-core PCF are measured. Fan-shaped PCF, band gap PCF, silver-filled PCF and V-shaped PCF are prepared, and the dispersion and loss of V-shaped PCF are simulated. The drawing parameters are fitted and compared. The parameter curve of furnace temperature presents an upward concave shape, and the parameter curve of air pressure threshold presents an upward convex shape. These fitting curves have reference value for the preparation of PCF in the future. • A method of preparing various PCFs by secondary drawing technology is proposed. • Various solid PCFs are prepared, and the core diameter is reduced to 4 um. • Two kinds of hollow-core PCFs are prepared. • Silver-filled and butterfly-shaped PCFs are prepared. [ABSTRACT FROM AUTHOR]

Two- and three-core photonic crystal fibers are prepared by using the same photonic crystal fiber preform structure. Not only the fiber diameter is reduced to standard size of 125 μ m , but also the core diameter is reduced to below 4 μ m. A curvature and temperature sensing system is built, and the curvature and temperature sensing performance of the three-core optical fiber is tested. When the length of three-core optical fiber is 150 mm, the measured curvature sensitivity is −7.27069 nm/m−1 in the range of 0 to 0.990 m−1, and the temperature sensitivity is −34 pm/°C during the temperature reduction from 75 to 45 °C. When the length of three-core photonic crystal fiber is 68 mm, the curvature sensitivity and temperature sensitivity are 2.42419 nm/m−1 and −7 pm/°C, respectively. In a small range of temperature, the sensor is insensitive to temperature, and the cross interference of temperature to curvature is very small. • Two- and three-core PCFs are prepared by using the same PCF preform structure. • The core diameter of three-core PCF is reduced to 3 μ m. • The measured curvature sensitivity is −7.27069 nm/m−1. • The cross-interference of temperature on curvature is very small. [ABSTRACT FROM AUTHOR]

Chromium (Cr) isotopes represent a powerful tool for tracing the redox conditions during planetary magmatic evolution. However, so far, the systematic investigation of Cr isotope variation has been only performed on ocean island basalts (OIBs) in terrestrial magmatic rocks. Therefore, the Cr stable isotope compositions (expressed as δ53Cr relative to NIST SRM 979) of other magmatic rocks, formed under different oxygen fugacity, have remained unconstrained. In this paper, we present the first Cr stable isotopic data of mid-ocean ridge basalts (MORBs) from the Eastern Pacific Ocean ridge, the Indian ridge, and the Atlantic Ocean ridge. The oxygen fugacity of such basalts is different from that of the above-mentioned OIBs. The Rhyolite-MELTS model shows that the chemical composition variations in the studied basalts are induced by varying extents of fractional crystallization of olivine, clinopyroxene, plagioclase, and spinel. The δ53Cr values of the MORBs range from −0.27 ± 0.03‰ to −0.07 ± 0.02‰ (n = 28), and two distinct groups of basalts are identified based on the correlation between δ53Cr and MgO. On the one hand, the δ53Cr of group I basalts (−0.27 ± 0.03‰ to −0.14 ± 0.03‰; n = 24) are systematically lower than the established average value of the Bulk Silicate Earth (BSE) (δ53Cr = −0.12 ± 0.04‰; 2SD), which are positively correlated with their MgO and Cr concentrations, indicating that Cr isotopes are fractionated during magmatic differentiation. Moreover, Rayleigh fractionation modelling suggests that the crystallization of olivine, clinopyroxene, and spinel gives rise to the Cr depletion and thereby decreases δ53Cr values. On the other hand, group II basalts (−0.10 ± 0.03‰ to −0.07 ± 0.02‰; n = 4) exhibit higher δ53Cr values than group I with identical MgO and Cr concentrations. This is possibly associated with the crystallization of clinopyroxene under low pressure. The average Cr isotope composition (δ53Cr = −0.16 ± 0.02‰, n = 3) of the primitive basalts (MgO > 9%) represents that of the primary MORB melt, which is lighter than the average value of BSE. Using the non-modal melting equations, the δ53Cr of the MORB mantle source is estimated to be −0.12 ± 0.02‰ (2σ), which is consistent with that of BSE. Compared with the Cr isotopic data of OIBs from Fangataufa island, we find that the equilibrium fractionation factors (Δ53Cr crystal-melt = +0.04‰ to +0.13‰) of MORBs during fractional crystallization are larger than that of Fangataufa island lavas (Δ53Cr crystal-melt = 0.010 ± 0.005‰ for low-K suite, and 0.020 ± 0.010‰ for high-K suite; Bonnand et al., 2020a), indicating that the basalts from Fangataufa island have higher oxygen fugacity than those of MORBs analyzed in this study, which is strongly supported by their higher V/Sc ratios. [ABSTRACT FROM AUTHOR]

In this paper, a high effective up-conversion luminescence agent (Er 3+ :Y 3 Al 5 O 12 ) is synthesized by sol–gel method, and then its corresponding visible-light photocatalysts (Er 3+ :Y 3 Al 5 O 12 /Pt-KNbO 3 ) are successfully prepared by hydrothermal and direct mixing methods. For comparison, Er 3+ :Y 3 Al 5 O 12 , Pt-KNbO 3 and Er 3+ :Y 3 Al 5 O 12 /Pt-KNbO 3 are all characterized by XRD (X-ray diffractometer), SEM(scanning electron microscopy) and EDX(energy dispersive X-ray spectroscopy ). At first, the visible-light photocatalytic activity of Er 3+ :Y 3 Al 5 O 12 /Pt-KNbO 3 is examined through photocatalytic hydrogen evolution from aqueous methanol solution under visible-light irradiation. Lastly, the influence factors such as Er 3+ :Y 3 Al 5 O 12 and Pt-KNbO 3 mass ratio, heat-treated temperature and initial pH value on the visible-light photocatalytic hydrogen evolution activity of Er 3+ :Y 3 Al 5 O 12 /Pt-KNbO 3 are studied. Particularly, Er 3+ :Y 3 Al 5 O 12 /Pt-KNbO 3 catalysts with 0.5:1.0 mass ratio heat-treated at 500 °C in aqueous methanol solution with initial pH = 6.0 show the highest photocatalytic activity in hydrogen evolution from aqueous methanol solution. [ABSTRACT FROM AUTHOR]

The adsorption of copper and other heavy metals onto clay minerals is an important process that controls the distribution of trace metals in natural environments. Copper isotopes are a potentially useful tool to track the source of contaminated metals in soils formed in natural systems, but Cu isotope fractionation during adsorption onto clay minerals, the major component in soils, has not been thoroughly studied. In this study, we carried out for the first time a series of experiments to investigate the isotope fractionation of Cu during adsorption onto kaolinite for a wide range of conditions, including the contact time (t = 10–360 min), temperature (T = 1–50 °C), initial Cu concentration of the starting solution (C 0 = 2–100 μg/g), pH value (4.0–6.0) and ionic strength (NaNO 3 ; I = 0–0.1 mol/L). Our results indicate that Cu isotopes are significantly fractionated with preferential adsorption of the light isotope ( 63 Cu) onto the mineral surface. The fractionation factors (Δ 65 Cu adsorbed-solution = δ 65 Cu adsorbed − δ 65 Cu solution ) weakly depend on the pH and temperature with a constant value of approximately − 0.27‰ at C 0 = 20 μg/g and in the absence of NaNO 3 . Addition of NaNO 3 into the starting solution has a dramatic negative influence on the Δ 65 Cu adsorbed-solution values that range from − 1.46‰ to − 0.29‰. Such results are useful for interpreting Cu isotopic variations observed in sediments, soils and water from estuarine settings or industrial sewage pollution areas. The Δ 65 Cu adsorbed-solution values significantly increase with increasing initial Cu concentration of the starting solutions at C 0 < 30 μg/g, but approach a stable value of − 0.17 ± 0.10‰ (2SD) when the kaolinite has reached its maximum adsorption capacity at C 0 > 30 μg/g. The results imply that the isotopic compositions of the Cu adsorbed onto natural soils may vary greatly at relatively low Cu concentrations of the soil solutions. Furthermore, the pore waters after draining kaolinite-bearing rocks would become isotopically heavier due to the preferential adsorption of 63 Cu onto kaolinite. Given that no redox change occurred in all experiments, we propose that the most likely mechanism responsible for such Cu isotope fractionation is the different adsorption capacities of isotopically different species in aqueous solutions and the formation of outer-sphere surface Cu(II) complexes. Our study represents one important step for future studies to use Cu isotopes to trace the source of metal contaminants in natural soils. [ABSTRACT FROM AUTHOR]

In this work, a novel up-conversion luminescence agent (Er 3+ :Y 3 Al 5 O 12 ) was synthesized by sol-gel method and then for visible-light photocatalytic hydrogen evolution a corresponding visible-light photocatalyst, platinum supported titanium dioxide nanocomposites coating up-conversion luminescence agent (Er 3+ :Y 3 Al 5 O 12 /Pt–TiO 2 nanocomposite particles), was successfully prepared by sol-gel and calcination methods. Er 3+ :Y 3 Al 5 O 12 , Pt–TiO 2 and Er 3+ :Y 3 Al 5 O 12 /Pt–TiO 2 were all characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM) and energy dispersive X-ray spectroscopy (EDX). The visible-light photocatalytic activity of Er 3+ :Y 3 Al 5 O 12 /Pt–TiO 2 nanocomposites was examined through photocatalytic hydrogen evolution from methanol splitting under visible-light irradiation. The influence factors such as Er 3+ :Y 3 Al 5 O 12 and Pt–TiO 2 mole ratio, heat-treated temperature and heat-treated time on the visible-light photocatalytic hydrogen evolution activity of Er 3+ :Y 3 Al 5 O 12 /Pt–TiO 2 nanocomposites were also studied. Particularly, Er 3+ :Y 3 Al 5 O 12 /Pt–TiO 2 nanocomposites with 1.5:1.0 M ratio heat-treated at 500 °C for 60 min showed the highest visible-light photocatalytic activity in hydrogen evolution from methanol splitting. [ABSTRACT FROM AUTHOR]

Iron and copper isotopes are useful tools to track redox transformation and biogeochemical cycling in natural environment. To study the relationships of stable Fe and Cu isotopic variations with redox regime and biological processes during weathering and pedogenesis, we carried out Fe and Cu isotope analyses for two sets of basalt weathering profiles (South Carolina, USA and Hainan Island, China), which formed under different climatic conditions (subtropical vs. tropical). Unaltered parent rocks from both profiles have uniform δ 56 Fe and δ 65 Cu values close to the average of global basalts. In the South Carolina profile, δ 56 Fe values of saprolites vary from −0.01‰ to 0.92‰ in the lower (reduced) part and positively correlate with Fe 3+ /ΣFe ( R 2 = 0.90), whereas δ 65 Cu values are almost constant. By contrast, δ 56 Fe values are less variable and negatively correlate with Fe 3+ /ΣFe ( R 2 = 0.88) in the upper (oxidized) part, where large (4.85‰) δ 65 Cu variation is observed with most samples enriched in heavy isotopes. In the Hainan profile formed by extreme weathering under oxidized condition, δ 56 Fe values vary little (0.05–0.14‰), whereas δ 65 Cu values successively decrease from 0.32‰ to −0.12‰ with depth below 3 m and increase from −0.17‰ to 0.02‰ with depth above 3 m. Throughout the whole profile, δ 65 Cu positively correlate with Cu concentration and negatively correlate with the content of total organic carbon (TOC). Overall, the contrasting Fe isotopic patterns under different redox conditions suggest redox states play the key controls on Fe mobility and isotope fractionation. The negative correlation between δ 56 Fe and Fe 3+ /ΣFe in the oxidized part of the South Carolina profile may reflect addition of isotopically light Fe. This is demonstrated by leaching experiments, which show that Fe mineral pools extracted by 0.5 N HCl, representing poorly-crystalline Fe (hydr)-oxides, are enriched in light Fe isotopes. The systematic Cu isotopic variation in the Hainan profile reflects desorption and downward transport of isotopically heavy Cu, leaving the organically-bound Cu enriched in light isotope as supported by the negative correlation of δ 65 Cu with TOC ( R 2 = 0.88). The contrasting (mostly positive vs. negative) Cu isotopic signatures in the upper parts of these two profiles can be attributed to the different climatic conditions, e.g., high rainfall at a tropical climate in Hainan favors desorption and the development of organism, whereas relatively dry climate in South Carolina favors Cu re-precipitation from soil solutions and adsorption onto Fe (hydr)-oxides. Our results highlight the potential applications of Fe and Cu isotopes as great tracers of redox condition, ancient climate and biological cycling during chemical weathering and pedogenic translocation. [ABSTRACT FROM AUTHOR]

In this work, we propose an octagonal photonic crystal fiber (PCF) filter based on tellurite. Selective gold coating in air holes couples the core mode to a surface plasmon mode. The finite element method is used to analyze the structure in the mid-infrared band. The simulated results and analysis show that the losses in the y and x polarization modes at 2.55 µm are 2063.2 and 21 dB/cm, respectively. Therefore, the unwanted y-polarization mode is filtered out. The higher loss ratio optimizes the formant position and intensity of surface plasmon mode and core mode. When the fiber length of the filter is optimized to 500 µm, the extinction ratio of − 102 dB is achieved at 2.55 µm. Consequently, the single polarization transmission with a 500 nm width is realized. When the length of the fiber is greater than 500 µm, it realizes the 1500 nm (2.2–3.7 µm) ultra-wideband filtering. We also analyze the manufacturing feasibility of the proposed PCF and the influence of structural parameters on the limiting loss characteristics. • Introduce a new type of substrate material: TZLB, which breaks the limitation of conventional quartz glass. • The loss of the y-polarization state is much higher than the x-direction. • When the fiber length is 500 µm, the ER reaches −102 dB and the effective filtering range is 2.4‐2.9 μm. • When the fiber length is greater than 500 µm, it achieves the 1500 nm ultra-wideband filtering. [ABSTRACT FROM AUTHOR]

Serpentinite is one of the most important sources of volatiles and fluid-mobile elements in subduction zones. Attempts have been made to discriminate serpentinite-derived fluid from other sources (e.g., sediments, altered oceanic crusts) using a variety of geochemical tools, but such differentiation has proven to be changeling because fluids from different lithologies are dynamically mixed in the subduction channel. Serpentinites are essentially distinguished by high Cr contents and variable degrees of 53Cr excess. Given high Cr mobility in Cl-rich metamorphic fluids based on experimental determination, Cr elemental and isotope compositions could be potential markers for fluid-mediated mass transfer from serpentinites. Here, we test this hypothesis by analyzing Cr concentrations and isotope compositions of meta-basalts, as well as country mica schists, marbles and serpentinites from the southwestern Tianshan Orogen. The meta-basalts have highly variable Cr concentrations (30.0–625 ppm) and resolvable δ53Cr variations (−0.25‰ to −0.05‰), while mica schists and marbles have similar isotope compositions and low Cr contents (δ53Cr of −0.15‰ to −0.14‰ with Cr contents of 89.5–110 ppm for mica schists, δ53Cr of −0.21‰ to −0.17‰ with Cr contents of 4.1–8.73 ppm for marbles, respectively). Most of the investigated meta-basalts were carbonated. The positive correlations of loss on ignition (LOI), CO 2 , Sb and Sb/Ce with Cr contents, as well as with δ53Cr for these carbonated meta-basalts indicate that the metamorphic fluids are at least partially sourced from serpentinites and sedimentary carbonates. High pressure serpentinites display similar δ53Cr variations from −0.19‰ to −0.02‰, but high Cr contents ranging from 934 to 4920 ppm. Chromium isotope variations of these serpentinites could not be generated by serpentinization, due to opposite trends of Cr isotopes and serpentinization indexes compared with previous observations. Instead, dehydration of serpentinites during subduction/exhumation accounts for Cr isotope variations, generating fluids with high Cr concentrations and relatively lighter isotope compositions. According to a Rayleigh dehydration model, the estimated Cr isotope fractionation factor (α fluid-residue) between fluids and residual serpentinites is approximately 0.99995 –0.99975, implying that Cr species in the subducted serpentine derived fluid is probably as complexes of Cr3+-Cl− H 2 O(OH–). The mixing model reveals that investigated carbonated meta-basalts were sourced from initial evolved oceanic basalts metamorphosed by fluids from serpentinite dehydrations, with contributions from sedimentary carbonates. This work emphasizes that coupled Cr element and isotope systems present the potential ability to discriminate the complex fluid sources in subduction zones, particularly serpentinites. [ABSTRACT FROM AUTHOR]

The four wave mixing (FWM) characteristics of highly nonlinear tellurite photonic crystal fiber are simulated. The material of tellurite fiber is TeO 2 -Li 2 O-ZnO-P 2 O 5 (TLZP). It is calculated that there are two zero dispersion points at 1590 nm and 3880 nm in tellurite photonic crystal fiber. The linear phase mismatch, the variation of optical signal gain with fiber length and the pump power are calculated at 1538 nm and 3865 nm respectively. The results show that the fiber has good four wave mixing performance near 1550 nm communication window and mid infrared region. [ABSTRACT FROM AUTHOR]

• The lightweighting of railway axles was investigated to reduce the unsprung mass. • A mid-fidelity design concept railway axle is presented. • A railway axle is dominated by combined bending moments rather than torsion. • Parametric sizing study for the composite axle is benchmarked against current steel axle. • Estimated mass reduction of 75% compared to the existing hollow steel axle. The potential for lightweighting of railway axles was investigated to primarily reduce the unsprung mass of a rail vehicle. The reduction of unsprung mass equates to an overall lighter train which will help to reduce track damage, energy consumption and total operating costs. This work was performed within the NEXTGEAR project which is ascribed under the Shift2Rail program. This paper focusses on the design of a composite railway axle as part of the "Wheelset of the future" Work Package 3. A parametric study is presented for the sizing of one of the design concepts (the full-length pre-manufactured tube axle) that shows the greatest potential for mass reduction. This study uses the existing hollow steel axle as a benchmark for mass, strength and stiffness. The estimated mass of this composite axle is 50 kg. This represents an estimated mass reduction of 75% compared to the existing hollow steel axle. [ABSTRACT FROM AUTHOR]

Widespread Cenozoic intraplate basalts from eastern China offer the opportunity to investigate the consequences of interaction between the stagnant Pacific slab and overlying asthenosphere and chemical heterogeneity within this "big mantle wedge". We present and compile a comprehensive study of highly siderophile elements and Mg-Zn isotopes of this magmatic suite (60 samples including nephelinites, basanites, alkali basalts and tholeiites). The large-scale Mg-Zn isotopic anomalies documented in these basalts have been ascribed to mantle hybridization by recycled Mg-carbonates from the stagnant western Pacific plate. Our results reveal that the nephelinites and basanites are characterized by unfractionated platinum-group element (PGE) patterns normalized to primitive upper mantle (PUM) (e.g., Pd N /Ir N normalized to PUM = 1.1 ± 0.8, 1σ), relatively high total PGE contents (e.g., Ir = 0.25 ± 0.14 ppb) and modern mantle-like 187Os/188Os (0.142 ± 0.020). These characteristics are coupled with lighter Mg isotope (δ26Mg = −0.48 ± 0.07‰) and heavier Zn isotope (δ66Zn = +0.46 ± 0.06‰) compositions compared to the mantle values (δ26Mg: −0.25 ± 0.07‰; δ66Zn: +0.18 ± 0.05‰). Together, these data are interpreted to reflect the oxidative breakdown of low proportions of mantle sulfides in the sources of these small-degree melts, likely caused by recycled carbonates, which then release chalcophile-siderophile elements into carbonatitic melts. By contrast, the contemporaneous alkali basalts and tholeiites are characterized by highly fractionated PGE patterns (e.g., Pd N /Ir N = 4.4 ± 3.3; Ir = 0.037 ± 0.027 ppb) and radiogenic 187Os/188Os (0.279 ± 0.115) coupled with less fractionated Mg-Zn isotope compositions (δ26Mg: −0.39 ± 0.05‰; δ66Zn: +0.35 ± 0.03‰). In combination with other isotopic (e.g., Sr-Nd) and chemical (SiO 2 , Ce/Pb, Ba/Th, Fe/Mn) constraints, the alkali basalts and tholeiites were derived from higher degree melting of ancient pyroxenite-bearing mantle in addition to mixing with the aforementioned nephelinitic and basanitic melts. Collectively, we suggest that deep recycled carbonates promoted melting within the "big mantle wedge" leading to the generation of Cenozoic intraplate basalts across eastern China and the "redox freezing of carbonates" may cause the oxidation of Fe0 and S2-. This process may provide an important mechanism to oxidize mantle sulfides and transfer precious metals from deep mantle to crust. [ABSTRACT FROM AUTHOR]

Photonic crystal fiber-based polarization filter has important application prospects in optical fiber communications, nonlinear optics, and sensors. In order to achieve polarization filters with optimal performance, some numerical methods have been used to search for optimal results under different geometric structure parameters of fibers. However, it is unrealistic to calculate solutions under every parameter. In addition, the search direction and scope of adjusting fiber geometric structure parameters still depend on the designer's intuition and experience. Therefore, we propose a novel design method for photonic crystal fiber polarization filters to overcome these questions. The optimization design problem of polarization filters is transformed into the single objective function optimization problem. The combination of artificial neural networks and intelligent optimization algorithms realizes the optimal value-solving problem in two-dimensional parameter space. The method efficiently and automatically searches for optimal structures in the parameter space by fine-tuning both variables simultaneously, improving the bandwidth of the polarization filter and achieving higher crosstalk at 1550 nm. The method eliminates computationally expensive wavelength parameters and greatly reduces computation time. This novel design method realizes the reverse design of photonic crystal fiber-based polarization filters. In addition, the new method can also be used to design polarization filters at other objective wavelengths, and it is potentially applicable to the design of other photonic crystal fiber devices. • Wavelength parameters are removed, drastically cutting down on computation time. • The polarization filters optimization design is transformed into function optimization. • Machine learning techniques provided optimal design parameters of polarization filters. [ABSTRACT FROM AUTHOR]

The multi-core few-mode fiber based on space division multiplexing technology is one of the critical ways to address the issue that the current single-mode fiber communication capacity has reached its maximum. However, the energy crosstalk between the cores is an important reason for the deterioration of signal quality. Consequently, this paper designs a nineteen-core seven-mode fiber with more transmission channels, and the auxiliary structures such as trench, high and low refractive index double rings, and air holes can effectively reduce intra-core crosstalk and inter-core crosstalk. After optimization, each core of the nineteen-core fiber can transmit seven LP modes, and the effective refractive index difference between adjacent modes is greater than or equal to 10−3. The optical fiber provides 228 transmission channels for the entire transmission system, the inter-core crosstalk of the highest order LP 41 mode is lower than −30 dB/100 km at 1550 nm. Based on the above, the proposed optical fiber has excellent optical properties and can be applied to data centers, optical sensors, high-speed computer communication networks, and other applications. [ABSTRACT FROM AUTHOR]

• First production of oligogalacturonides (OGs) directly from citrus peel wastes. • An innovative green and novel fermentation strategy has been developed. • After fermentation for 72 h, the DP of OGs was ranging from 2 to 7. Citrus wastes disposal is a problem faced by many juice plants due to high disposal costs. However, the citrus peel wastes (CPW) biomass, as bulk bioresources from the agro-industrial waste, is a good source of pectin. Present study aimed to utilize these CPW biomass by engineered yeast strain fermentation with an inexpensive method to produce oligogalacturonides (OGs). The results showed that the engineered yeast strain fermentation can produce significant amounts of OGs with the degree of polymerization ranged from 2 to 7 from the CPW bioresources. Under the optimized conditions using the response surface methodology, the best OGs yield were 26.1%. The present work is the first to use the engineered yeast strain for direct CPW biomass fermentation produced the OGs. We thereby paved a new way to utilize the pectin-rich bioresources. [ABSTRACT FROM AUTHOR]

A dual-polarized microstructure fiber sensor is based on surface plasmon resonance, which is arranged of pentagonal lattice to achieve refractive index sensing in the near-infrared spectrum. The gold nanowire-filled fiber sensor exhibits excellent sensing characteristics and improved transmission properties. Finite element method is used for computational analysis and structural optimization for the fiber sensor. When the refractive index of the analyte range from 1.32 to 1.38, dual-polarizd sensing can be implemented as a self-calibration with wavelengths increasing from 700 to 1200 nm. For the proposed sensor, the highest wavelength sensitivity of 10,286 nm/RIU is exhibited with a sensor resolution of 9.72×10−6 RIU, and the corresponding amplitude sensitivity and figure of merit are as high as 544.0 RIU−1 and 146.9. Moreover, the sensing length of at least 1.14 mm ensures accurate detection of optical signals for proposed sensor. Owing to the above advantages, the proposed sensor is suitable for high integration and high precision sensitivity detection. [ABSTRACT FROM AUTHOR]

A damage model for linear viscoelastic unidirectional (UD) composites undergoing transverse matrix cracking is proposed. The damage representation for the corresponding elastic UD composite with an array of dispersed matrix cracks was derived from Li's work based on continuum damage mechanics (CDM). The elastic-viscoelastic correspondence principle (CP) was used to obtain the damage representation for corresponding linear viscoelastic UD composites in the Laplace domain, and re-expressed in the time domain by taking the inverse Laplace transformation. A damage evolution law was constructed using the Weibull distribution of defects which will develop into cracks as a result of deformation. The time-temperature superposition principle (TTSP) approach has been incorporated into this model. Applications of this damage model are described in detail, and the predictions are compared with experimental data. [ABSTRACT FROM AUTHOR]

Phthalates are widespread endocrine-disrupting chemicals (EDCs) that have been suggested to affect neurodevelopment. However, association between lactational exposure to phthalates and neurodevelopmental effects has rarely been reported in epidemiological studies. We conducted a pilot prospective study of 138 mother-infant pairs to evaluate whether lactational exposure to phthalates was associated with neurodevelopmental effects in infants. At baseline survey, the spot urine samples from both mothers and infants were collected for measuring ten metabolites of phthalates, and the food intake information of infants was assessed by the food-frequency questionnaire (FFQ). At the follow-up survey in 9 months of age, the neurodevelopmental Function of infants was assessed using the Ages and Stages Questionnaire Edition 3 (ASQ-3). Multivariate logistic regression models were used to calculate the odds ratio (OR) for delayed development according to the level of exposure to phthalates. Our results indicated that MnBP and MiBP were high in lactating infants and mothers. In the overall study population, most metabolites showed positive associations with delayed development of most ASQ-3 domains. In male, MMP, MEP, MiBP and MnBP but not DEHP metabolites were significantly associated with increased odds of delayed development of all domains. In female, most LMWP metabolites and the four oxidative metabolites of DEHP were significantly associated with increased odds of delayed development of most domains. In conclusion, we found a significant negative association between lactational exposure to phthalates and ASQ-3 domains. Some of the sex-specific observations warrant further investigation. The dietary source of lactational phthalates exposure may not the breast milk or infant formula but the complementary food. Image 1 • MnBP and MiBP seem to be high in both lactating infants and mothers. • Urinary metabolites of mothers and infants were highly correlated. • Lactational exposure to multiple phthalates may influence neurodevelopment in infants. • Breast milk and infant formula may not the major source of lactational phthalates exposure. • Complementary food may the source of lactational phthalates exposure. [ABSTRACT FROM AUTHOR]

Abstract Cycling of elements with multiple valences (e.g., Fe, C, and S) through subduction and magmatism may dictate the redox evolution of the deep mantle and atmosphere. To investigate the potential of Fe isotopes as a tracer of such cycles, here we report Fe isotopic compositions of thirty-seven Cenozoic basalts from eastern China. A nephelinitic melt component with δ 56 Fe up to 0.29 has been identified, which cannot be explained by weathering, alteration, magma differentiation, or chemical diffusion. Its low Fe/Mn ∼58, relatively low TiO 2 and high Na 2 O + K 2 O argue against a significant contribution of pyroxenite melting. Instead, the heavy Fe component requires enhanced isotope fractionation during partial melting of a peridotitic source with Fe3+/ΣFe ≥ 0.15. Low Ba/Th ∼ 50 and depleted 87Sr/86Sr(i) and ε Nd (t) suggest that the source was insignificantly affected by hydrous fluids and recycled terrigenous sediments. The heavy Fe component is known to be unique in its low δ 26 Mg and high δ 66 Zn and indicates hybridization by recycled carbonates. The source Fe3+/ΣFe was most likely enhanced at cost of reduction of recycled carbonates to diamonds in a mantle depth ≥300 km. The origin of the heavy Fe component illustrates a pathway with net transportation of oxidizer back to Earth's surface: CO 2 (in carbonates) → C (as diamond frozen in the deep mantle) + O 2 (ferric Fe being scavenged by melt extraction). Secular cooling of global subduction zones may have stepwisely increased the efficiency of this carbon driven deep oxygen cycle in the past, providing an alternative explanation for the rise of atmospheric O 2. Highlights • Three magma components are identified in Cenozoic basalts from eastern China. • A nephelinitic and heavy Fe component has δ 56 Fe up to 0.29. • Two tholeiitic components have δ 56 Fe typical of MORB and most OIB. • The heavy Fe component from a peridotitic source oxidized by recycled carbonates. • Illustration of a deep oxygen cycle induced by subducted carbonates. [ABSTRACT FROM AUTHOR]

Abstract A series of CdSe QDs are synthesized using four kinds of ligands including dodecylamine, tetradecylamine, 1-hexadecanamine and octadecylamine by organic metal preparation method. The XRD patterns revealed that all the CdSe QDs with different amine ligands belong to cubic phase. The monodisperse CdSe QDs are obtained and their average size increases with the Carbon chain length of amine ligands. The absorption peaks of CdSe QDs capping with different amines shift from 526 to 557 nm. The results indicated that the luminescent properties and size of CdSe QDs can be modulated by amine ligand in the process of synthesis. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A novel glucanase with high activity to hydrolyse curdlan powder was identified. • A novel curdlan pre-treatment method increase glucanase degradation rate. • The degradation mode of glucanase was analyzed. Abstract Curdlan is a water-insoluble microbial exo-polysaccharide that is hardly degraded. The gene CcGluE encoding an endo-β-1→3-glucanase consisting of 412 amino acids (44 kDa) from Cellulosimicrobium cellulans E4-5 was cloned and expressed in Escherichia coli. The recombinant CcGluE hydrolysed curdlan powder effectively. CcGluE shows high endo-β-1→3 glucanase activity and low β-1,4 and β-1,6 glucanase activities with broad substrate specificity for glucan, including curdlan, laminarin and β-1→3/1→6-glucan, and the highest catalytic activity for curdlan. Moreover, the hydrolytic products of curdlan were glucan oligosaccharides with degrees of polymerisation of 2–13, and the main products were glucobiose and glucotriose. Degradation mode analysis indicated that CcGluE is more likely to hydrolyse glucopentaose and revealed that CcGluE was an endo-glucanase. Furthermore, upon combination with a homogenising pre-treatment method with curdlan, the degradation efficiency of CcGluE for curdlan powder was greatly improved 7.1-fold, which laid a good foundation for the utilisation of curdlan. [ABSTRACT FROM AUTHOR]

Abstract The effect of human exposure to phthalates and consequent contribution to the development of cardiometabolic health problems is unknown. However, oxidative stress has been established as playing an important role in the pathogenesis of cardiometabolic outcomes. In this study, we aimed to explore whether exposure to phthalate metabolites could induce cardiometabolic risk by increasing oxidative stress in a diabetic population from Shanghai. We collected paired blood and urine samples from a total of 300 volunteers, and measured 10 phthalate metabolites in urine and biomarkers of oxidative stress from serum including glucose and lipid levels, and liver and kidney damage. The insulin resistance (IR) risk was assessed by the surrogate indices including homeostasis model assessment-insulin resistance (HOMA-IR) and triglyceride glucose (TyG). We used multivariable linear regression to assess the association between phthalates and these physiological parameters. Mediation and modification analyses were performed to identify the role that oxidative stress played in the underlying mechanisms. The results showed that most of the determined phthalate metabolites were positively associated with HOMA-IR, 8‑hydroxy‑2′‑deoxyguanosine (8-OHDG), and malondialdehyde (MDA). In the mediation analysis, only γ‑glutamiltransferase (GGT) was found to be a significant mediator of the association between phthalates and TyG. In the modification analysis, exposure to phthalates strengthened the association between oxidative stress (MDA and 8-OHDG) and HOMA-IR. Our findings demonstrate that exposure to phthalates might be positively associated with elevated IR and oxidative stress. The direct participation (mediation effect) of GGT might play an important mechanism in promoting IR. Highlights • The exposure to phthalates was associated with elevated IR and oxidative stress. • The association between phthalates and IR was fully mediated by GGT. • The association between IR and MDA (or 8-OHdG) was moderated by phthalates. [ABSTRACT FROM AUTHOR]

Abstract Recent studies show that zinc isotopes could provide valuable clues to environmental change and biogeochemical cycle of the past oceans. This study reports a modified procedure for leaching the carbonate fractions in sedimentary rocks, a thorough evaluation of diagenetic effects, and systematic variations of Zn and Sr isotope ratios in lower part of the Ediacaran stratigraphic unit deposited in the aftermath of the Marinoan glaciation in South China. The influence of post-depositional diagenesis on Zn isotope compositions of the studied samples is assessed by comparing δ66Zn to other geochemical indexes (87Sr/86Sr, δ13C, δ18O and Mn/Sr ratios). In the five studied cap carbonate sections (Member I of the Doushantuo Formation), dolostones from four sections have δ66Zn values positively correlated with δ18O values and negatively correlated with 87Sr/86Sr ratios (0.7081–0.7204). These correlations suggest that these cap dolostone samples have been modified by post-depositional diagenesis. The light δ66Zn value (−0.02‰) suggests that initial Zn isotope ratios of cap dolostones could have been reset by hydrothermal fluids with relatively high Zn concentration and low δ66Zn values. By contrast, carbonates from Member II of the Doushantuo Formation above cap dolostones are relatively pristine based on their low 87Sr/86Sr ratios (0.7079–0.7086) being indistinct from the proposed early Ediacaran seawater 87Sr/86Sr values. Chemical and isotopic variations in these samples are interpreted to reflect primary signals that record paleo-environmental changes of the early Ediacaran ocean. A rapid increase of δ66Zn from ∼0.3‰ to 1.1‰ occurs in the middle part of Member II, accompanying by relatively invariant 87Sr/86Sr ratios that imply insignificant changes in input from continental weathering. Considering the limited change in atmospheric oxygen during this period, the rapid δ66Zn raise indicates an increase in buried organic matters, which is consistent with the coupled positive shift of δ13C carb , as well as the fossil records found in the same strata. These results provide insights into Zn cycling in the post-Marinoan oceans and facilitate the application of Zn isotopes in carbonates as a proxy for the fate of marine organic matter. [ABSTRACT FROM AUTHOR]

Phthalates are predominantly used as plasticizers in daily consumer products. People are regularly exposed to phthalates through contact with these products. Phthalates are suspected to cause adverse effects in general population. We detected 10 metabolites of 6 phthalates in 3348 urine samples of general population (infants (0–1 yr), children and adolescents (2–19 yr), adults (≥20 yr), and pregnant women) from Shanghai. The Daily intake for phthalates was estimated based on the levels of urinary metabolites. Hazard quotient (HQ) was used to evaluate the risk from the exposure to a single chemical. For the cumulative risk calculation, HQs of different phthalates were added to produce the Hazard index (HI). Overall, exposure was low in adults but presented at a relatively high level throughout childhood. The exposure to some specific phthalates was high in infants and pregnant women. The cumulative risk assessment showed cause for concern mainly for infants and children subgroups. The results indicated that general population from Shanghai was widely exposed to phthalates and the infants were possibly at a high risk of cumulative exposure to phthalates. [ABSTRACT FROM AUTHOR]

• A low-cost and easy-to-manufacture surface plasmon resonance temperature sensor was implemented. • The sensor has an ultra-wide temperature detection range. • Ethanol is used as a temperature-sensitive material for high-sensitivity temperature sensing. • The sensor has high reliability and repeatability. In this work, a temperature sensor is proposed and experimentally demonstrated using a low cost surface plasmon resonance (SPR) system based on optical fiber. The sensor is formed by splicing a short length of no-core fiber (NCF) with two multimode fibers (MMFs). A silver film is deposited on the NCF to excite SPR effect. Overcome the defect of the complex fabrication process of the existing optical fiber sensor. The sensing characteristics at different deposition times have been studied. Experimental results show that for low and medium–high temperature, the sensitivity of the sensor is −3.01 and −1.425 nm/°C, respectively. It has a wide detection range from −40 to + 70 °C. The sensor also showed good reliability after repeated experiments. The temperature sensor covering low and medium–high temperature has important application value in agricultural production and soil temperature monitoring. [ABSTRACT FROM AUTHOR]

Thermal expansion properties of textile reinforced composites with certain structure symmetries can be efficiently calculated by a size-limited unit cell. In this paper, a general approach is developed for the establishment of such a unit cell model. For the derivation of unit cell boundary conditions, three rules are summarized according to the displacement fields in translational, reflectional and 180° rotational symmetric structures under a uniform temperature change loading. The application scope of present unit cell method is clarified from the thermal and mechanical point of views. Three typical composites, i.e., unidirectional fiber reinforced composite, plain woven composite and multi-harness (4HS, 5HS, 6HS, 7HS and 8HS) satin woven composites are then studied, and four, three and two size-reducing unit cells are formulated, respectively. The thermal expansion behaviors of each composite are analyzed, and the effective thermal expansion coefficients are predicted. The influence of structure symmetries on the deformation pattern of unit cell models is clarified. The numerical models are validated by the identical results obtained from unit cells of different sizes and also by the results available in literatures. The approach developed in this paper can be applied to thermal expansion studies of any other composites with relevant structure symmetries. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus small colony variants (SCVs) can cause persistent infections. However, the genomes and transcriptomes of S. aureus SCVs remain poorly understood. A pair of isogenic wild-type and SCV methicillin-resistant S. aureus (MRSA) strains (IE1 and IE2, respectively) were isolated from a patient with prosthetic valve infectious endocarditis. The SCV strain IE2 grew more slowly than the wild-type strain, and serum killing and mouse lethality assays revealed that the virulence of SCV strain IE2 was decreased. Whole-genome sequencing of the SCV and wild-type strains revealed 15 mutations in nine genes associated with metabolism, virulence and DNA repair, including serine/threonine-protein kinase PrkC ( prkC ), glycerol-3-phosphate acyltransferase ( plsY ), 2-deoxyribose-5-phosphate aldolase ( deoC ), extracellular adherence protein ( eap ), iron compound ABC uptake transporter substrate-binding protein ( sstD ), RecU Holliday junction resolvase ( recU ), excinuclease ABC subunit B ( uvrB ), type I restriction–modification system, M subunit ( hsdM ) and smooth muscle caldesmon. Sequencing of RNA transcripts revealed that expression levels of 321 genes were upregulated and 582 genes were downregulated in SCV strain IE2 compared with IE1. Most of the differentially expressed genes were involved in metabolism. Expression levels of several genes involved in the pathways to which plsY , deoC , eap and sstD belonged were changed, associated with the metabolism and virulence of S. aureus . In conclusion, the reduced growth rate and decreased virulence of MRSA SCV strains may be related to mutations in and downregulation of genes associated with metabolism and virulence, especially plsY , deoC , eap and sstD . [ABSTRACT FROM AUTHOR]

Optimization design of thermal protection system of aerospace vehicles with progressively increasing flying speeds needs a deepened study on the thermal conduction characteristics of corresponding materials. As a potential thermal protection material, C/C-SiC 8-harness (8HS) satin woven composites with piercing fiber bundles are numerically studied in this work. The numerical model is established based on the investigation of 8HS satin weave textile. A full and a half unit cell models are formulated according to three non-orthogonal translational and one further 180° rotational symmetries, respectively. The two unit cells have much smaller sizes and also less computational costs than the rectangle unit cell available in previous literatures. The thermal boundary conditions are derived rigorously and are verified by the identical numerical results obtained by the two unit cells. The developed unit cell method and the related boundary conditions derivation process can be references for other multi-harness satin woven composites. The numerical model is validated by the experimental result obtained in this work and that available in the literature. The influences of constituents (carbon fiber, matrix C, matrix SiC and porosities) volume fractions, piercing fiber bundles and thermal contact resistance between matrix and fiber bundles on the effective thermal conductivities are studied. [ABSTRACT FROM AUTHOR]

Significant magnesium and iron isotope fractionations were observed in an adjacent gabbro and granite profile from the Dabie Orogen, China. Chilled margin and granitic veins at the gabbro side and gabbro xenoliths in the granite indicate the two intrusions were emplaced simultaneously. The δ 26 Mg decreases from −0.28 ± 0.04‰ to −0.63 ± 0.08‰ and δ 56 Fe increases from −0.07 ± 0.03‰ to +0.25 ± 0.03‰ along a ∼16 cm traverse from the contact to the granite. Concentrations of major elements such as Al, Na, Ti and most trace elements also systematically change with distance to the contact. All the observations suggest that weathering, magma mixing, fluid exsolution, fractional crystallization and thermal diffusion are not the major processes responsible for the observed elemental and isotopic variations. Rather, the negatively correlated Mg and Fe isotopic compositions as well as co-variations of Mg and Fe isotopes with Mg# reflect Mg-Fe inter-diffusion driven isotope fractionation, with Mg diffusing from the chilled gabbro into the granitic melt and Fe oppositely. The diffusion modeling yields a characteristic diffusive transport distance of ∼6 cm. Consequently, the diffusion duration, during which the granite may have maintained a molten state, can be constrained to ∼2 My. The cooling rate of the granite is calculated to be 52–107 °C/My. Our study suggests diffusion profiles can be a powerful geospeedometry. The observed isotope fractionations also indicate that Mg-Fe inter-diffusion can produce large stable isotope fractionations at least on a decimeter scale, with implications for Mg and Fe isotope study of mantle xenoliths, mafic dikes, and inter-bedded lavas. [ABSTRACT FROM AUTHOR]

Compared with traditional optical fiber, photonic crystal fiber (PCF) has many novel optical properties owing to its diversity in cladding distribution. But, it is a problem to measure the optical properties of PCF under variable structural parameters. Artificial neural networks (ANNs) have been used to predict the optical properties of PCF, but ANNs have the multiple local minima problems, whereas support vector machines' solutions are globally unique and will not fall into local minimum values. In this paper, support vector machines (SVMs) based on radial basis functions were used to predict the effective refractive index (n e f f), chromatic dispersion (D), and confinement loss (α c) of PCF. Well-trained SVMs can accurately and quickly predict the optical properties of any geometric parameters in the studied parameter space. A data set similar to Gaussian distribution was formed by two logarithmic transformation methods to avoid the problem that machine learning models cannot be well trained on extremely skewed distribution. Compared to ANNs, SVMs are more accurate and show stable prediction results. [ABSTRACT FROM AUTHOR]

Background Diet is considered to be a significant exposure pathway for phthalates. In this study, we assessed the associations between food consumption and urinary concentrations of phthalate metabolites among Shanghai adults. Methods A cross-sectional study involving 2418 participants was conducted in the fall of 2012. Recent food consumption was assessed by a 24-h dietary recall survey, and a Food Frequency Questionnaire (FFQ) characterized long-term dietary patterns. Urinary metabolites of six phthalates were measured. Results Both the 24-h recall survey and FFQ identified wheat, dairy, and fruits as being positively associated with the excretion of phthalate metabolites. The 24-h recall data also showed positive associations with processed meats and alcohol. We evaluated the impact of reported consumption of multiple food categories simultaneously (wheat, fruits, meats, etc.) on metabolite excretion and found that, as more food types were consumed, the number of metabolites excreted, as well as their concentrations, increased with high significance (p values < 0.0001). We also evaluated the two survey instruments together. When both surveys reported consumption of fruits and dairy, the numbers of metabolites and their concentrations were significantly higher compared to when both surveys reported non-consumption, (p values < 0.000001). Rice consumption was found to be negatively associated with phthalate excretion; frequent and high levels of rice consumption were found to be associated with lower excretion of metabolites. Conclusion Food consumption was associated with phthalate exposure in Shanghai adults. Both 24-h recall and FFQ identified significant associations between consumption of food types and phthalate exposure. [ABSTRACT FROM AUTHOR]

Based on the structure of the full unit cell which is formulated by three translational symmetries, three further 180° rotational symmetries of three-dimensional (3D) four-directional braided composites are clarified in this paper. It is for the first time that each rotational symmetry is used to reduce the full unit cell to a half, quarter, and eighth size. The corresponding boundary conditions for thermal analysis are derived precisely according to each rotational transformation. The effective thermal conductivities of composites with different fiber volume fractions and interior braiding angles are calculated by the full, quarter and eighth unit cells. In order to confirm the significance of accurate boundary conditions, additional comparison calculations with adiabatic boundary conditions are conducted and the result reveals that inappropriate boundary conditions may lead to an un-neglectable error in the prediction of thermal conduction behaviours. The numerical model is validated by good agreement between the numerical results and the available experimental ones. [ABSTRACT FROM AUTHOR]

This study reports elemental and iron isotopic compositions of feldspar and its coexisting minerals from four Dabie I-type granitoids to evaluate the factors that control inter-mineral Fe isotopic fractionation in granitoids. The order of heavy iron isotope enrichment is feldspar > pyrite > magnetite > biotite ≈ hornblende. Feldspar has heavier iron isotopic compositions than its co-existing magnetite (Δ 56 Fe plagioclase–magnetite = +0.376‰ to +1.084‰, Δ 56 Fe alkali-feldspar–magnetite = +0.516‰ to +0.846‰), which can be attributed to its high Fe 3+ /Fe tot ratio and low coordination number (tetrahedrally-coordinated) of Fe 3+ . Δ 56 Fe magnetite–biotite of coexisting magnetite and biotite ranges from 0.090‰ to 0.246‰. Based on homogeneous major and iron isotopic compositions of mineral replicates, the inter-mineral fractionation in this study should reflect equilibrium fractionation. The large variations of inter-mineral fractionation among feldspar, magnetite and biotite cannot be simply explained by temperature variation, but strongly depend on mineral compositions. The Δ 56 Fe plagioclase–magnetite and Δ 56 Fe alkali-feldspar–magnetite are positively correlated with albite mode in plagioclase and orthoclase mode in alkali-feldspar, respectively. This could be explained by different Fe–O bond strength in feldspar due to different Fe 3+ /∑Fe or different crystal parameters. The Δ 56 Fe magnetite–biotite increases with decreasing Fe 3+ /∑Fe biotite and increasing mole (Na + K)/Mg biotite , indicating a decrease of β factor in low Fe 3+ /∑Fe and high (Na + K)/Mg biotite. High-silica leucosomes from Dabie migmatites with a feldspar accumulation petrogenesis have higher δ 56 Fe values (δ 56 Fe = 0.42–0.567‰) than leucosome that represents pristine partial melt (δ 56 Fe = 0.117 ± 0.016‰), indicating that accumulation of feldspar could account for high δ 56 Fe values of these rocks. High δ 56 Fe values are also predicted for other igneous rocks that are mainly composed of cumulate feldspar crystals, e.g., anorthosites. Feldspar accumulation, however, cannot explain high δ 56 Fe values of most high-silica granitoids reported in the literature, based on their low Sr, Ba contents and negative Eu anomalies. [ABSTRACT FROM AUTHOR]

• A liquid level (Li-Le) sensor with refractive index (RI) compensationwas experimentally investigated. • A maximum Li-Le and RI sensitivities of 875 pm/mm and 250.11 nm/RIU respectively were achieved. • The measured Li-Le could be obtained from a contour map of wavelengths and liquid RIs. A liquid level (Li-Le) optical fiber sensor with refractive index (RI) compensation through cascading double multi-mode interferences (MMIs) sensors was experimentally investigated. Previous researches showed that the sensitivities of Li-Le sensor were interfered by the variation in liquid RIs significantly, which illustrated the necessity of RI compensation in Li-Le sensors. In this work, we designed a Li-Le sensor by cascading a Li-Le sensor and a RI sensor, where the RI sensor was used for the RI compensation in Li-Le detection. The sensitivity of Li-Le sensor varied with the increase of liquid RI. The RI sensor could achieve the RI compensation in the RI range of 1.333–1.370. A contour map was plotted to effectively determine the Li-Le from the disturbing of liquid RI. The maximum sensitivity of Li-Le was 875 pm/mm when the liquid RI was 1.4164, which was higher than most of the previous works. This designed RI compensation Li-Le sensor could become a competitive candidate in the field of accurate detection of Li-Le for the advantages of high sensitivity, simple structure, and RI compensation. [ABSTRACT FROM AUTHOR]

The comprehensive design feasibility for woven composites has been established by identifying the missing component in the design tool for these materials, the so-called controllable parameters. These are the parameters that are involved, directly or indirectly, in manufacturing of woven preforms, and they include the tow densities, the number and the size of filaments in a tow and intra-tow fibre volume fractions. Controllable parameters have been related through a simple procedure to the conventional geometric parameters of woven composites, which eliminates the need for their costly, inefficient, and often unreliable measurements. The controllable parameters provide sufficient representation of woven geometry in terms of both modelling and manufacture, thus offering common terminology to the woven composite designers and manufacturers. This also allows to naturally involve the practical considerations and manufacturing restrictions in material design exercises. With controllable parameters being incorporated in woven composite design framework, a direct analogy can be drawn to classical lamination theory-based design for conventional laminates. The wide applicability of the design tool has been demonstrated via a series of systematic material characterisation exercises carried out with woven composites of sufficiently different internal architectures and constituents, which also showed good predictive capability of the models involved. [Display omitted] [ABSTRACT FROM AUTHOR]

• An ultrahigh-sensitive fiber-optic temperature sensor based on cascaded Sagnac interferometers with a nematic liquid crystal film was proposed and experimentally demonstrated. • The molecules of NLC film changed from isotropic to isotropic just by rotating the two single-mode patch cables without any orientation agent, electric, or magnetic devices. • Experimental results revealed that the temperature sensor based on the cascaded configuration showed an ultrahigh sensitivity of 43.13 nm/°C, which was amplified about 5 times contrast to a single Sagnac interferometer. We demonstrated an ultrasensitive fiber-optic temperature sensor based on cascaded Sagnac interferometers (CSIs). One of the Sagnac interferometers (SIs) consisted of a panda polarization-maintaining fiber (PMF) as the reference arm, while the other one contained two single-mode patch cables in a ferrule matching sleeve as the sensing arm, where a nematic liquid crystal (NLC) film was infiltrated into the micron-scale gap of the sleeve. In the sensing SI, the orientation of NLC film was induced by just rotating the two single-mode patch cables without any orientation agent, electric, or magnetic devices. Vernier effect was acquired by adjusting the thickness of NLC film. Experimental results revealed that the temperature sensitivity of the CSIs was up to 43.13 nm/°C, which was enhanced about 5 times compared to the single NLC SI. The designed optical fiber temperature sensor possessed the merits of compact structure, high stability, ultrahigh sensitivity, low hysteresis effect and high resolution, showing a promising application prospect in some scientific filed requiring accurate temperature measurement, such as biomolecules, medicine and other filed. [ABSTRACT FROM AUTHOR]

In order to find an efficient enzymatic tool for curdlan degradation to produce (1 → 3)-linked β- d -glucan oligosaccharides, strain E4-5 (registration number JN089883, Genbank) was isolated from seaside soil. The 16S rRNA gene sequencing classified it as Cellulosimicrobium cellulans . It was the first reported microorganism that succeeded in degrading high-set heated curdlan blocks. The ferments of strain E4-5 also showed good degradation effects on laminaran and alkali-neutralized curdlan. Due to the products with less amount of glucose, it was assumed that endo-1,3-β-glucanases of strain E4-5 had a greater hydrolyzing effect than exo-1,3-β-glucanases. This indicated that strain E4-5 was a promising microorganism to hydrolyze (1 → 3)-linked β- d -glucan. Moreover, alkali-neutralization pretreatment was effective for promoting a more diversified degree of polymerization (DP) of (1 → 3)-linked β- d -glucan oligosaccharides under enzymatic hydrolysis and will pave the way for making full use of curdlan for production of glucan oligosaccharides. [ABSTRACT FROM AUTHOR]

• This work presents a refractive index and temperature plasmonic sensor based on photonic crystal fiber. • In order to achieve the best performance, a serial of study on the theory and experimental steps is carried out, including simulation calculation, detection system, coating method and post-processing technology. • Experimental results demonstrate that an average sensitivity of 3381 nm/RIU within a linear refractive index ranging from 1.3333 to 1.3860 can be achieved, which is greater than the traditional fiber structure. • In addition, this sensor is helpful to measure temperature change and the sensitivity could be 2 nm/°C. • This study presents a lot of effective methods for preparing PCF sensor, which has enlightening significance to design optical device. In this paper, a refractive index and temperature plasmonic sensor based on photonic crystal fiber is proposed. In order to achieve the best performance, a serial of study on the theory and experimental steps is carried out, including simulation calculation, detection system, coating method and chemical etch technology. Experimental results demonstrate that a high average sensitivity of 3381 nm/RIU within a linear refractive index ranging from 1.3333 to 1.3860 can be achieved, which is greater than the traditional fiber structure. In addition, this sensor is helpful to measure temperature change and the sensitivity could be 2 nm/°C. Due to its easy and controllable fabrication, the proposed sensor has great application prospects in the field of optical device. [ABSTRACT FROM AUTHOR]