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Objective: There is concern that the coronavirus disease (COVID-19) vaccine may trigger or worsen autoimmune diseases. The objective of this study was to determine the impacts of COVID-19 vaccination on symptom severity in patients with myasthenia gravis (MG). Methods: A total of 106 enrolled patients with MG who were vaccinated against COVID-19 were followed up, and a questionnaire was used to document in detail the exacerbation of muscle weakness after vaccination and all other uncomfortable reactions after vaccination. Demographic, clinical characteristics, medication, and vaccination data were collected by follow-up interview. The main observation outcome was whether the MG symptoms of patients were exacerbated. The definition of exacerbation is according to the subjective feeling of the patient or a 2-point increase in daily life myasthenia gravis activity score relative to before vaccination, within 30 days after vaccination. Results: Of 106 enrolled patients [median age (SD) 41.0 years, 38 (35.8%) men, 53 (50.0%) with generalized MG, 74 (69.8%) positive for acetylcholine receptor antibody, and 21 (19.8%) with accompanying thymoma], muscle weakness symptoms were stable in 102 (96.2%) patients before vaccine inoculation. Muscle weakness worsened in 10 (9.4%) people after vaccination, of which 8 patients reported slight symptom worsening that resolved quickly (within a few days). Two (1.9%) of patients showed serious symptom aggravation that required hospitalization. Conclusion: Our results suggest that inactivated virus vaccines against COVID-19 may be safe for patients with MG whose condition is stable. Patients with generalized MG may be more likely to develop increased muscle weakness after vaccination. [ABSTRACT FROM AUTHOR]

Ni 25 Ti 25 Hf 25 Cu 25 medium entropy shape memory alloy (MESMA) exhibit reversible B2↔B19′ martensitic transformation. Martensitic morphology is represented by (011) type I twins with low density of inner (001) compound twins. In a bending test, Ni 25 Ti 25 Hf 25 Cu 25 exhibits reversible strain of 2.4% under stress of 300 MPa. [Display omitted] • Ni 25 Ti 25 Hf 25 Cu 25 exhibits B2↔B19′ MT. • Low density of (001) compound twins into martensitic variants. • Recoverable strain of 2.4% under stress of 300 MPa. [ABSTRACT FROM AUTHOR]

Fuzzy C-means (FCM) clustering algorithm is a widely used method in data mining. However, there is a big limitation that the predefined number of clustering must be given. So it is very important to find an optimal number of clusters. Therefore, a new validity function of FCM clustering algorithm is proposed to verify the validity of the clustering results. This function is defined based on the intra-class compactness and inter-class separation from the fuzzy membership matrix, the data similarity between classes and the geometric structure of the data set, whose minimum value represents the optimal clustering partition result. The proposed clustering validity function and seven traditional clustering validity functions are experimentally verified on four artificial data sets and six UCI data sets. The simulation results show that the proposed validity function can obtain the optimal clustering number of the data set more accurately, and can still find the more accurate clustering number under the condition of changing the fuzzy weighted index, which has strong adaptability and robustness. [ABSTRACT FROM AUTHOR]

Detrital peat (organic carbon-enriched deposit) with high arsenic (As) content is widely distributed in sediments where groundwater As contamination exists. Iron sulfides often persist in these sediments under anoxic conditions. However, the mechanisms and pathways of formation of iron sulfides and its potential contribution in controlling As mobility are still poorly understood. In this study, we examined three As-contaminated peat sediments from the Hetao Basin in China to gain better understanding of the complex interplay between iron sulfides formation and As mobility. We employed high-resolution spectroscopic techniques, including X-ray absorption spectroscopy and 57Fe Mössbauer spectroscopy, coupled with electron microscopy to determine the speciation of iron sulfides and the associated As in the peat sediments. Pyrite (FeS 2) and metastable greigite (Fe 3 S 4) persisted in peat as end-members of S and Fe diagenetic pathways. The Fe-rich phyllosilicates and decaying plant tissues provided the ideal micro-environments for pyrite and greigite nucleation. Pyrite formation most likely occurred via the polysulfides pathway in the surface water-sediments interface during early diagenetic process, while the relative enrichment of reactive Fe compared to sulfide possibly inhibited the transformation of greigite to pyrite in such Fe-rich sediments. Our results revealed that the peat sediments could act as a stable sink for As immobilization under steady groundwater anoxic conditions, with As content up to 250 mg/kg and large proportions (40 to 60 wt.% As) sequestered in pyrite and greigite. Pyrite crystallites had up to 1 wt.% As content through the replacement of the S-I sites. Greigite crystallites had a relatively constant As content ranging from ∼500 to ∼1400 mg/kg. Instead of being adsorbed or structurally incorporated, arsenic formed distinct arsenic sulfide phase in the greigite-enriched sediments, which was analogous to realgar. The transfer of As from iron sulfides to ferrihydrite temporarily retarded As release into groundwater under slightly oxic groundwater conditions. However, the reductive dissolution of ferrihydrite and potential subsequent As re-release could be a source of As in groundwater under disturbed redox conditions. [ABSTRACT FROM AUTHOR]

The structure and magnetic properties of (Fe[sub 56]Pt[sub 44])[sub 100-x]N[sub x] alloy films with x=0–15 at. % prepared by rf magnetron sputtering were investigated. Compared to an Fe[sub 56]Pt[sub 44] binary film, (Fe[sub 56]Pt[sub 44])[sub 100-x]N[sub x] alloy films showed great enhancement in hard magnetic properties. A coercivity H[sub c] of 1027 kA/m, a remanence M[sub r] of 1.24 T, and a maximum energy product (BH)[sub max] of 260 kJ/m3 were obtained for an (Fe[sub 56]Pt[sub 44])[sub 93]N[sub 7] film annealed at 600 °C for 10 min, whereas the Fe[sub 56]Pt[sub 44] film annealed at the same conditions gave H[sub c]=682 kA/m, M[sub r]=0.87 T, and (BH)[sub max]=132 kJ/m[sup 3]. Structural analysis revealed that N addition influenced the phase structure and microstructure of FePt films. N atoms incorporated in the disordered FePt phase in as-deposited films, they released rapidly out of the FePt phase by vacuum annealing. It is suggested that the rapid release of N atoms from the FePt phase promotes the transformation to the ordered phase, results in a higher coercivity of the film. The high remanence of the (Fe[sub 56]Pt[sub 44])[sub 93]N[sub 7] film is attributed to enhanced exchange coupling of the soft iron nitride phase and the hard FePt phase. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Presents information on a study which investigated soft magnetic properties and thermal stability of iron-titanium-nitrogen alloy films. Composition of the thin film; Application of the reactive sputtering method; Experimental results.

Decarburization means carbon in rail material lost in the hot rolled process. It changes the microstructure of rail materials and will influence their rolling contact fatigue (RCF) characteristic. The objective of this study is to explore the effect of decarburized layer on rolling contact fatigue and propagation mechanism of crack under the wet condition using a rolling-sliding wear testing machine. The results show that the crack growth rate on the decarburized rail roller is over 4 times than that on the non-decarburized rail. Small pitting presents on the non-decarburized rail roller, which is dominated by transgranular crack. While, long mouth surface crack dominates on the decarburized rail roller and the cracks mainly grow along the ferrite line or the grain boundary. With the cycles increasing, the surface cracks of decarburized rail roller gradually break and forms spalling damage, eventually expands to bulk spalling. Meanwhile, the crack growth mechanism changes back to the transgranular propagation and propagates in depth with a large angle when the decarburization is worn off. [ABSTRACT FROM AUTHOR]

• Mg doping enlarges temperature span and reduces hysteresis. • Impurity phase and the order of magnetic phase transition control hysteresis. • Covalent bond length adjust the Curie temperature. Magnetocaloric materials with wide working temperature span and reversible magnetic transition are beneficial for the magnetic refrigerator. Besides of giant magnetocaloric effect, (Mn,Fe) 2 (P,Si) alloys exhibit significant thermal/magnetic hysteresis and a narrow working temperature span. In this work, the impact of Mg doping on the phase structure and magnetocaloric effect of Mn 1.05 Fe 0.9 P 0.5 Si 0.5- x Mg x alloys has been studied. The results show that all samples crystallize into Fe 2 P-type main phase with little impurity phase. After Mg doping, the lattice parameter a of the main phase increases from 6.027(0) Å to 6.049(0) Å and c decreases from 3.488(6) Å to 3.480(6) Å, which leads to the increase of Curie temperature. Density functional theory calculation results confirm that the Mg atom located on the 2c site can increase the covalent bond length, and then enhance the ferromagnetic coupling between atoms leading to the increase of Curie temperature. Moreover, the first-order magnetic phase transition of Mn 1.05 Fe 0.9 P 0.5 Si 0.5- x Mg x alloys is inhibited with the increase of Mg content, which results in the decrease of thermal/magnetic hysteresis and the increase of the effective working temperature span. For Mn 1.05 Fe 0.9 P 0.5 Si 0.48 Mg 0.02 alloy, it has a Curie temperature of about room temperature, effective refrigeration capacity of 291.7 J·kg−1, working temperature window of 46 K and magnetic entropy change of 9.4 J·kg−1·K−1. The alloy can be an excellent candidate in room temperature magnetic refrigeration devices with a wide temperature span. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the nutrient composition and AME n content of corn distillers dried grains with solubles (DDGS) to develop prediction equations for AME n in laying hens. Ten samples of DDGS ranging in ether extract (EE) from 21.8 to 177.8 g/kg (DM basis) were selected and were subsequently fed to laying hens to determine AME n content. A total of 176 62-week-old laying hens (Lohmann-Pink) were placed in metabolic cages (2 hens/cage) and were allotted into 11 dietary treatments (8 cages per treatment) according to hen-day egg production. Dietary treatments included a corn-soybean meal reference diet and 10 test diets. Each test diet was created by mixing the reference diet with 200 g/kg one of 10 DDGS samples at the expense of the energy-yielding ingredients (139.6 g/kg corn, 59.0 g/kg soybean meal, and 1.4 g/kg rapeseed oil). Experimental diets were fed in the 7-day adaptation period, followed by the 4-day total excreta collection period. Gross energy (GE) and crude protein (CP) of the experimental diets and excreta were determined to calculate AME n for each DDGS sample. On the DM basis, AME n of the 10 corn DDGS samples ranged from 729 to 2535 kcal/kg. Analyses were conducted to determine the GE, CP, EE, DM, crude fiber, neutral detergent fiber (NDF), acid detergent fiber (ADF), and ash content of the DDGS samples. Stepwise regression resulted in the following best-fit equation for AME n (DM basis) based on the coefficient of determination, SE, and the Mallows’ statistic (Cp): AME n , kcal/kg = 0.777 × GE (kcal/kg) − 5.39 × NDF (g/kg) (R 2  = 0.99; SE = 172; C p  = −3.37). These results suggested that the composition of corn DDGS may be used to predict AME n in laying hens. [ABSTRACT FROM AUTHOR]

Elastic-plastic response is greatly involved in the failure of wire ropes. Based on the derivation of the local deformation parameters of individual wire, an analytical model characterizing the elastic-plastic behavior for both wire strands and multi-strand ropes is developed in this paper. Also, the contact status within a multilayered strand is carefully studied to achieve a full understanding of wire stresses. Details of the surface strain fields of ropes are captured by 3D digital image correlation (3D-DIC) technique and the results agree well with the prediction of the present model. Varying loading conditions are considered to analyze the yielding and failure behavior of wire strands. It is found that the rotation of ropes (no matter its positive or negative) will increase the overall stress level over the wire cross section, however, restraining the rope ends leads to higher contact stress. Increasing the helix angle moderately may be an effective method to reduce the contact pressure of strand wires. Our model provides straightforward prediction of the elastic-plastic response of wire ropes and proves an effective tool for rope design due to a great reduction of time consuming in numerical simulations. [ABSTRACT FROM AUTHOR]

Uniaxial stress-controlled ratcheting behaviors of expanded PTFE (ePTFE) under cyclic compressive loads were tested. The effects of temperature, stress rate and mean stress on the ratcheting behaviors of ePTFE considering multiple load paths were discussed in detail. Results present that the steady ratcheting strain is rate-independent when the stress rate is less than about 0.1 MPa/s, while it approximately linearly decreases with increasing the stress rate for greater stress rate. Additionally, the steady ratcheting is temperature-independent when the temperature is greater than about 150 °C, but it nearly linearly increases with enhancing the temperature for lower temperature. Especially, the stress rate almost has little effect on the ratcheting strain of ePTFE at 200 °C. Moreover, the accumulated ratcheting strain enhances rapidly in about the first 80 cycles, and subsequently tends to shakedown in the subsequent cycles for each load path. Furthermore, if a higher stress is used in the prior cycling, the greater ratcheting strain may be produced, and a negative ratcheting strain rate can be obtained in the subsequent cycling with lower mean stress due to the greater strain hardening and deformation resistance produced by the previous higher stress. [ABSTRACT FROM AUTHOR]

We propose a scheme of all-optical clock recovery (AOCR) based on ultrahigh-order mode locking by a semiconductor optical amplifier (SOA), which can directly extract the optical clock from non-return-to-zero (NRZ) pseudo-random-binary-sequence (PRBS) data. Firstly we demonstrate that the active mode locking system can generate stable high repetition frequency ultrashort pulse train, and adjusting the modulator's bias voltage and polarization states one can realize doubling the repetition frequency. Due to robust mode locking configuration, we successfully realize the AOCR up to 40 Gbits/s from the PRBS (231-1) NRZ optical signals without NRZ to RZ conversion, while the signal to noise ratio of the recovered optical clock is more than 20 dB with high stability, and the pulse width is short as 1.85 ps. Owing to the ultrafast nonlinear polarization rotation in the SOA, our scheme can execute AOCR for data rate of 100 Gbits/s and more. • Propose and demonstrate a novel scheme of all-optical clock recovery (AOCR) based on ultrahigh-order (>2000th) mode-locked laser. • Using actively mode-locking technology we generate high-stable high-frequency (11 GHz) optical pulse train. • Successfully carry out the all-optical clock recovery from 40 Gbits/s PRBS NRZ optical signals. • The scheme has the ability to recover optical clock signals from 100 Gbits/s data. [ABSTRACT FROM AUTHOR]

A contact trajectory model of ball bearings under the dynamic condition was developed by the means of the development of the integrated multi-body dynamics and multi-freedom kinematics with the multi-interfacial contact mechanics. Subsequently, the general methodology was employed to investigate the dynamic contact performance of ball bearings, particularly for the contact trajectory along the raceways due to each ball against the inner and outer raceways. It was found that the radial loading and inner ring misalignment could lead to the deviation of the contact trajectory on the raceways. The variation of contact angle could bring into the correspondence with the deviation of the contact trajectory on the raceways. The oscillation frequency of the contact trajectory on the outer raceway was higher than one on the inner raceway either under the axial and radial loading or misalignment condition. [ABSTRACT FROM AUTHOR]

Studies phase formation in annealed sputtered (Fe,Ti)-N thin films. Use of X-ray diffraction and transmission electron microscopy; Variations in annealing temperatures.

By using the high-pressure melt infiltration technique, a syntactic foam is fabricated with bulk metallic glass and alumina cenospheres. Compared to pure metallic glass foams, the new foam possesses a greatly enhanced energy absorbing capacity of 113.6 MJ m − 3 due to the combination of high strength, stability and ductility. It is shown that the high strength of the foam primarily results from alumina cenospheres, which enhance its stability and induce a stable stress platform. Both the collapse of struts and multiple shear bands in metallic glass matrix accommodate large deformation. [ABSTRACT FROM AUTHOR]

When the thicknesses of the outer layers are different in sandwich rolling, based on the different kinds of arrangements with the hard and soft materials the thickness ratio of two outer layers is changed differently during the rolling process. After the first analysis of the different outer thicknesses sandwich rolling, the rules for final thickness ratio of the two outer layers are proposed. In soft–hard–soft sheets (s–h–s) the thickness ratio of outer layers is remained in the final bonded sandwich sheet however in hard–soft–hard sheets (h–s–h) the thickness ratio is alleviated by sandwich rolling itself. A model based on slab method is proposed to analyze this phenomenon and 4 groups of experiments with Al and Cu as well as steel are conducted. The results calculated by the model well agree with those measured in the experiments. Then the accuracy and worthy of the model are verified. [ABSTRACT FROM AUTHOR]

The study aimed to determine the ileal phosphorus (P) digestibility (iPD) and the excreta P retention (ePR) of 5 monodicalcium phosphate (MCP) samples and 3 dicalcium phosphate (DCP) samples in broiler chickens and in Pekin ducks using the substitution method. A total of 720, 21-d-old Arbor Acres broiler chickens in experiment 1 and 720, 15-d-old Pekin ducks in experiment 2 were randomly allocated to 9 dietary treatments with 8 replicate cages (10 birds/cage) based on the similar mean body weight, respectively. The collection of excreta (for 72 h after a 3-d acclimation) and ileal digesta (after 6 d of feeding experimental diets) was done. The results showed the average iPD/ePR of MCP and DCP for broilers were 83.11%/74.52% and 75.34%/69.46% and for ducks were 79.37%/80.02% and 75.74%/76.44%, respectively. The iPD/ePR of MCP in broilers and the ePR of MCP in ducks were markedly higher (P < 0.05) than those of DCP. Our data suggest that using the substitution method to evaluate the bioavailability of feed phosphates has its own advantages; MCP has higher biological availability than DCP for broilers and ducks. [ABSTRACT FROM AUTHOR]

A new model characterizing the response of a multi-strand wire rope subjected to axial tension and axial torque is presented in this paper. Apart from most of previous approaches which deal with a straight wire strand, the present model fully considers the double-helix structure in multi-strand configuration. To be further, a new method to compute local deformation parameters (two curvatures and a twist defined by Love, 1944) of each wire is introduced. The proposed model well predicts the global stiffness of the rope. It is found that different friction states between adjacent wires can lead to quite a different distribution of local bending and torsion deformation of double-helix wire. The variations of stresses in double-helix wires along the rope axis are analyzed and the results show that torsion stress of a double-helix wire can be neglected when the rope is subjected to axial tension (axial torsion is restrained). The present model provides a new way to estimate the local deformation and stresses at the wire level, which sheds new insight into the understanding of the fatigue and failure behavior of the wire rope. [ABSTRACT FROM AUTHOR]

Light aroma style liquor is one of the basic types of Chinese liquor and is produced with a special technique of using a combination of three types of Daqu as starter culture. The succession of incubation temperature, a main operating parameter, and microbial composition in Daqu were investigated during the manufacturing process. The most significant difference in temperature occurred during the middle stage at which the highest and the lowest temperatures were detected in Houhuo (HH) and Qingcha ( QC), respectively. It was shown that for the counting data, the population of fungi was identical and that of bacteria was different between three types of Daqu. According to analysis results of microbial community structure using PCR-denaturing gradient gel electrophoresis ( PCR- DGGE), lactic acid bacteria were one of the dominant bacterial groups in all of Daqu and fungal diversity in QC was higher than that in HH and Hongxin (HX). The difference in incubation temperature led to the accumulation of different heat-tolerant and heat-sensitive fungi in the completed Daqu. PCA of DGGE profiles revealed that microbial community structure was distinct between three types of Daqu. It was presumed that temperature might play a decisive role in the formation of micro-organism composition in starter cultures. Significance and Impact of the Study The usage of a combination of three types of Daqu including Qingcha, Hongxin and Houhuo as starter culture is an important characteristic of production technology of Chinese light aroma style liquor. Micro-organisms from the environment naturally inoculated in Daqu are propagated to form the special microbial community under the control of several operating parameters, especially temperature, and finally play various roles in the fermentation process of liquor. An in-depth study of the relationship between incubation temperature and microbiota in Daqu during the manufacturing is fundamental to understand this complicated process and to prepare high-quality starter culture for fermentation. [ABSTRACT FROM AUTHOR]

Highlights: [•] A micro-sensor is developed to measure the internal temperature of a fuel cell. [•] A 3D CFD analysis is performed to analyze the fuel cell temperature. [•] In-plane temperature distribution is compared with experimental and numerical results. [Copyright &y& Elsevier]

Abstract: Laser weld bonding (LWB) is a hybrid welding technology that combines laser welding and adhesive bonding. In the hybrid welding process, the adhesive significantly affects the welding process and the property of the LWB joint. Results show that the adhesive partially decomposes in the heat-affected zone, the impaired size of which is mainly attributed to laser beam power. The property of the LWB joint is influenced by the thermal impaired area and adhesive thickness. To control the adhesive thickness and reduce the weld porosities in the fusion zone, a metallic interlayer is added in the welding process of LWB. [Copyright &y& Elsevier]

Abstract: This paper studies the optimization method of channel geometries for a proton exchange membrane fuel cell (PEMFC) using a genetic algorithm (GA). The channel and rib widths and channel height are selected as geometry variables. The fuel cell output power is chosen as the cost function for the optimization. In this paper, an in-house genetic algorithm is constructed, and the fuel cell output power is obtained using an interfacing program connected to a commercial computational fluid dynamics (CFD) tool, COMSOL, in a Matlab environment. The 2D PEMFC is used to calculate the performance cost function for computational time and cost. The calculated output power of the PEMFC is delivered to the in-house GA program to check for optimality. After the optimality is checked, the new geometry data is fed back to the COMSOL to calculate the PEMFC output power until the optimization process is finished. Experiments are conducted to support the optimized results using three different channel geometries: channel-to-rib width ratios of 0.5:1, 1:1, and 2:1. A full 3D PEMFC CFD model is constructed using COMSOL to support the 2D CFD optimization results. This paper shows the possibility of applying the geometry optimization process to sophisticated electrochemical reaction systems, such as a PEMFC, using a GA and a commercial CFD tool on the Matlab platform. The geometries and materials can be optimized using this approach to obtain the most efficient performance of an electrochemical system. [Copyright &y& Elsevier]

Abstract: Oxygen plasma ion implantation on the common elastomer polydimethylsiloxane (PDMS) can induce wrinkled and disordered surface morphologies. Here we present a convenient approach of generating (sub)micron-sized features, in order to control the development of such ripple-like features during plasma treatment process. The correlations between the spontaneous patterns with different surface treatment conditions, such as plasma bias voltage and processing time, as well as the effect of surface prepatterns, were studied. The presence of prepatterns suppressed the formation of ripples on the implanted PDMS surfaces, which is advantageous for eliminating the rough surface topologies induced in plasma-treated samples. [Copyright &y& Elsevier]

Abstract: Based on Density Functional Theory (DFT), using first-principles pseudopotential plane wave method, surface relaxation, surface energy and Density of states (DOS) of metal W on low index surfaces (001), (110) and (111) were calculated. The results showed that: the relaxation and surface energy were |Δ14(110)|<|Δ14(111)|<|Δ14(001)| and Esurf(110)

Abstract: Core-shelled structures such as zinc oxide (ZnO) on carbon nanotubes (CNTs) give rise to interesting material properties. In this work, a triple-layered core–shell–shell structure is presented where the effects of fluorine (F) incorporation on the outmost shell of the ZnO-CNT structure are studied. The samples prepared ranged from a short 2min to a 30min immersion in carbon tetraflouride (CF4) plasma. In addition, its effects on the electron emission properties also studied and it is shown that the plasma immersions create thinner field emitters with sharp tiny wrinkles giving rise to more electron emission sites and higher enhancement factor. In addition, X-ray photoelectron spectroscopy measurements showed that F ions replace O in ZnO coatings during immersion process, thus increasing the electrical conductivity and shifts the Fermi level of ZnO upwards. Both physical and electronic effects further contribute to a lower threshold field. [Copyright &y& Elsevier]

The influence of regression (partial dissolution) effects on the temperature dependence of nucleation rate in a binary solid solution has been studied theoretically. The results of the analysis are compared with the predictions of the simplest Volmer–Weber theory. Regression effects are shown to have a strong influence on the shape of the curve of nucleation rate versus temperature. The temperature TM at which the maximum rate of nucleation occurs is found to be lowered, particularly for low interfacial energy (coherent precipitation) and high-mobility species (e.g. interstitial atoms). [ABSTRACT FROM AUTHOR]

Abstract: Most CFD tunnel fire simulations have so far focused on the thermal field and the critical velocity for suppression of the hot backlayering flow. However, there is a great need in understanding the characteristics of a real-scale tunnel fire in terms of the flame propagation and the toxic gas generation. In this study, an extension of the eddy dissipation concept incorporating two chemical reaction steps is integrated into an internationally recognised CFD fire simulation code. A full-scale over-ventilated tunnel fire is simulated with the model and the measured temperature profiles are correctly reproduced. The model is then used to investigate the characteristics of a tunnel fire in three aspects: the length of backlayering, the flame length and the effects of an object within the tunnel. An inverse dependence of the backlayering length with the wind velocity, and the levelling-off of a maximum of the backlayering length for a ventilation velocity of 2m/s are predicted. Both the CFD prediction and an analytical correlation indicate that an increase of the heat generation rate enhances the flame length, and while, a growth of the ventilation velocity shortens the flame length. The effects of blockage in a tunnel on the propagation of smoke and fire are numerically investigated with the model. The results of this study have shown that the model is promising in qualitatively examining the correlation of the propagation of smoke, the production and the transport of carbon monoxide and soot with the ventilation rate and the fire heat release rate. [Copyright &y& Elsevier]

The resistance of nanoporous dentin biomaterial to CO2 laser irradiation was investigated by experiment and simulation for potential tooth hypersensitivity treatment. The controlled parameters including laser power of 0.03-0.150 W, scanning speeds of 11.4-34.2 mm/s and focus/defocus modes were used for studying interaction between laser energy and dentin of human tooth. Most of the dentin specimens were etched after CO2 laser irradiation with the power larger than 0.12 W at a scanning speed of 11.4 mm/s. Compared with the simulation results of temperature distribution, the maximum temperature at laser powers from 0.12 to 0.15 W is increased from 1961 to 2245°C, which exceeded the melting point (1570°C) of dentin's main content hydroxyapatite (HA). Increasing scanning speed can reduce the linear density of laser output energy for just locally melting porous microstructure of dentin surface without etching. Varying focus mode can also improve the damage of nanoporous dentin microstructure. At parameters of 0.150 W power and 34.2 mm/s scanning speed under defocus operation, laser treatment was successfully performed on the nano-HA coated dentin with well-molten sealing on tubules of porous microstructure at a simulate surface temperature of about 574°C, which was the potential for dentin hypersensitivity cure application. [ABSTRACT FROM AUTHOR]

Abstract: Effect of C particle size on the mechanism of self-propagation high-temperature synthesis (SHS) in the Ni–Ti–C system was investigated. Fine C particle resulted in a traditional mechanism of dissolution-precipitation while coarse C particle made the reaction be controlled by a mechanism of the diffusion of C through the TiC x layer. The whole process can be described: C atoms diffusing through the TiC x layer dissolved into the Ni–Ti liquid and TiC were formed once the liquid became supersaturated. Simultaneously, the heat generated from the TiC formation made the unstable TiC x layer break up. However, with the spread of Ti–Ni liquid, a new TiC x layer was formed again at the interface between spreading liquid and C particle. This process cannot stop until all the C particles are consumed completely. [Copyright &y& Elsevier]

Abstract: The nature convection of the liquid LiPb, due to thermal diffusion, in the poloidal channel perpendicular to the strong magnetic field in the blanket has been considered and studied. The cubic enclosure filled by the liquid metal LiPb flow is assumed as the analyzed model. It was numerical simulated by three-dimensional CFD with special MHD code. The Hartmann number is from 20 to 200. The wall of the enclosure was heated by a uniform temperature and the other wall was cooled along two opposite vertical walls, all other walls being adiabatic. The momentum equation and electrical-magnetic equations for the liquid LiPb flow in the enclosure have given. It is assumed the nature convection be steady-state conditions. The velocity and temperature of the LiPb flow with differential Hartmann number is discussed. The temperature distribution is changed due to magnetic field. The heat convection is enhanced by the high Hartmann number which the magnetic field intensified the motion of the LiPb fluid in the side layer. There is a strong thermal coupling, modifying importantly the magnitude of the flow. [ABSTRACT FROM AUTHOR]

Abstract: Moisture effect on the dielectric behavior and structure of BaTiO3-based devices were studied systematically. The dielectric measurement mainly concerned the capacitance and loss of specimen as a function of frequency and temperature between −10 and 50°C in different measuring environments (vacuum, ambient air with and without dryer). A broad peak of capacitance and loss due to the moisture absorption, depending on frequency and temperature rate and corresponding to a dynamic process involving water absorption and de-absorption, was observed in the heating run when the measurement was carried out in ambient air without dryer. It showed that water absorption would change the apparent dielectric properties of devices and a heat treatment at 50°C for the BaTiO3-based devices was suggested to reduce the moisture absorption effect. [Copyright &y& Elsevier]

Abstract: The paper presents a novel configuration of floating breakwater and its performance in waves. The structure is fabricated with large numbers of diamond-shaped blocks so arranged to reduce transmitted wave height and the mooring force. Two mooring modes, directional mooring and bidirectional mooring are considered in the tests. The influence of an impermeable vertical sidewall on transmission coefficient is estimated. The results examined under the present investigations are: K t, wave transmission coefficient (K t=H t/H i, H t—transmitted wave height, H i—incident wave height); K r, reflection coefficient (K r=H r/H i, H r—reflected wave height); E loss , the value of the dissipation of incident wave energy; and mooring force per unit length of the breakwater (F w denotes windward mooring force and F l denotes leeward mooring force for directional mooring, and F 1, F 2, F 3 and F 4 are four mooring forces for bidirectional mooring) of two mooring modes without sidewall. For the case of floating breakwater with impermeable sidewall, measured transmission coefficient K T (K T=H T/H, H T—the measured wave height in front of the sidewall, H—the wave height without structure and sidewall) is offered. The experimental results show that the proposed floating breakwater can reduce incident wave height by dissipating wave energy more than reflecting it. [Copyright &y& Elsevier]

Abstract: Reaction behaviors and products of thermal explosion reaction from Ni–Ti–C system under air and Ar atmosphere were investigated, respectively. The ignition temperature for the thermal explosion reaction under air is much lower than that under Ar atmosphere. Under two atmospheres, increasing the Ni content and Ti particle size can increase the ignition temperature, respectively. Under air, increasing Ni and C particle sizes can decrease the ignition temperature, but the opposite results are achieved under Ar atmosphere. The reaction products are mainly dependent on the C particle size under two atmospheres. [Copyright &y& Elsevier]

Abstract: We carried out a systematic investigation of microstructures in a particular zone of Si multicrystals which shows a strong local variation in minority carrier diffusion length (MCDL). It was found that three typical regions with distinct microstructures correspond to the microscopic origins of the local MCDL difference. The region with perfect twin structure (Σ3 boundaries) has a high MCDL, while the regions with either high-angle grain boundaries (Σ9 and Σ27 boundaries) or sub-grain boundaries (high density dislocation) exhibit lower minority carrier diffusion. The relationships between the microstructures and the corresponding MCDLs are briefly discussed. This study has implications for developing improved Si multicrystals with appropriate microstructure for application in solar cells. [Copyright &y& Elsevier]

Abstract: The fracture of the laser welded bonding (LWB) Mg to Al alloy joint was analyzed. In order to find the cracks source, the microcracks in LWB fusion zone were observed by scanning electron microscopy (SEM), comparing with that in the laser welding joint. The formation of the microcracks in LWB Mg to Al joint was discussed simply. The addition of the adhesive reduced the temperature contrast between the Mg–Al eutectic phase and the intermetallics. Thus, the stress concentration at the interface between the Mg–Al eutectic phase and the intermetallics was released. With the effect of the adhesion, the tensile shear test specimen of LWB joint was failed at the edge of the joint, the property of which was better than that of laser welding and adhesive bonding. [Copyright &y& Elsevier]

Abstract: Influence of Al addition on the products of self-propagating high-temperature synthesis (SHS) reaction in Al–Ti–Si system is investigated. When Al content is 0wt.%, the product only consists of Ti5Si3. When the Al addition is varied over the range of 5–15wt.%, the TiAl3 phase appears along with the Ti5Si3 phase. Besides Ti5Si3 and TiAl3, the transient phase Ti5Si4 is also detected in the final products when Al content increases over the range of 20–40wt.%. However, both the Ti5Si3 and Ti5Si4 phases disappear completely when Al content further increases to 50wt.%; only TiAl3 phase and trace of Al exist in the final products. Moreover, increase in Al content causes a decrease in Ti5Si3 and an increase in TiAl3 amount, which indicates that Al not only serves as a diluent but also participates in the SHS reaction process. Furthermore, the solubility of Si in TiAl3 increases significantly with Al addition increasing, while that of Al in Ti5Si3 mainly depends on the Al content in the Al–Ti–Si system. In addition, the Al incorporation has a great effect on the microstructure formation and evolution of the SHS reaction products. When Al content is less than 15wt.%, the final product mainly consists of Ti5Si3; however, which changes into Ti5(Si,Al)3 as Al content increases to 20–25wt.%, and then turns into another solid solution Ti(Al,Si)3 when Al content further increases to 30–50wt.%. Consequently, the microstructure evolution may be summarized as follows: Ti5Si3 →Ti5(Si,Al)3 →Ti(Al,Si)3. [Copyright &y& Elsevier]

Abstract: The linear response of 2D wedge-shaped premixed flames to harmonic velocity disturbances was studied, allowing for the influence of flame stretch manifested as variations in the local flame speed along the wrinkled flame front. Results obtained from analyzing the G-equation show that the flame response is mainly characterized by a Markstein number , which measures the curvature effect of the wrinkles, and a Strouhal number, , defined as the angular frequency of the disturbance normalized by the time taken for the disturbance to propagate the flame length. Flame stretch is found to become important when the disturbance frequency satisfies , i.e. . Specifically, for disturbance frequencies below this order, stretch effects are small and the flame responds as an unstretched one. When the disturbance frequencies are of this order, the transfer function, defined as the ratio of the normalized fluctuation of the heat release rate to that of the velocity, is contributed mostly from fluctuations of the flame surface area, which is now affected by stretch. Finally, as the disturbance frequency increases to , i.e. , the direct contribution from the stretch-affected flame speed fluctuation to the transfer function becomes comparable to that of the flame surface area. The present study phenomenologically explains the experimentally observed filtering effect in which the flame wrinkles developed at the flame base decay along the flame surface for large frequency disturbances as well as for thermal-diffusively stable and weakly unstable mixtures. [Copyright &y& Elsevier]

Abstract: Numerical study is performed by using a large eddy simulation to give a quantitative description of the toxic products (CO, soot), temperature stratification and heat fluxes from a circular pool fire in a longitudinally ventilated tunnel. The turbulent combustion process is modelled by an eddy break-up concept by using two sequential, semi-global steps to CO prediction. The numerical model solves three-dimensional, time-dependent Navier–Stokes equations, coupled with submodels for soot formation and thermal radiation transfer. The smoke movement is modelled as an unsteady process, from the time of ignition until convergence to a quasi-steady state. The computed, time-averaged temperatures are compared with experimental data from a full-scale ventilated tunnel, and a relatively good agreement is attained. Below a critical ventilation velocity, the back layer flow carries the CO and soot production towards the entry, and an inverse dependence of the backflow length to ventilation velocity is predicted. For the tunnel hydraulic height of 3.3m considered here, the heat-release rate (HRR) approaches a maximum of approximately 35MW, beyond which the critical ventilation velocity is unchanged even though the theoretical HRR continues to increase. In the case where HRR reaches to a maximum, the high-temperature level (T>500°C) in the smoke layer and the strong heat flux (>20kW/m2) pose significant threat to people or combustible objects exposed downstream the fire source, potentially inducing flashover within tunnel. This study highlights the utility of field modelling for the analysis of fires and smoke (CO and soot) movement in tunnels. [Copyright &y& Elsevier]

Abstract: Influence of reactant (Cr, Ti and B4C) particle size on the SHS reaction products in 30wt.% Cr–Ti–B4C system has been investigated. Particle size of Cr powder has a significant effect on the phase compositions and microstructures of SHS reaction products. The SHS reaction in Cr–Ti–B4C system with nano-size Cr goes more complete and occurs more easily than that in the system with micron-size Cr. Increase in particle size of B4C powder has a little effect on the phase compositions of SHS reaction products, which consist of TiB2, TiC and Cr phases as well as transient phase Cr5B3 and a trace of C, but results in the increase of the amount of Cr5B3. Furthermore, the average sizes of TiB2 and TiC increase from ∼0.5 and ∼1μm to ∼2 and ∼3μm, respectively, as the B4C particle size increases from ∼3.5 to 40μm. Increase in particle size of Ti powder (∼38, ∼48 and ∼74μm) has little influence on the phase compositions of the products, as well as average sizes and morphologies of TiB2 and TiC. [Copyright &y& Elsevier]

Abstract: Fires can expose concrete to extreme temperatures. Thus, it is important to know the effect of elevated temperature on the concrete property. High performance concrete (HPC) often contains other supplemental cementitious materials besides cement, such as ground granulated blast furnace slag (GGBFS) and chemical admixtures such as superplasticizer (SP). GGBFS has been used successfully to improve concrete properties. This paper investigates the effects of GGBFS on concrete properties at elevated temperature. A total of 588 test specimens were prepared with three water-to-binder (W/B) ratios and six different GGBFS contents. The test specimens were cured for 28 days and then subjected to seven different elevated temperatures of up to 1050°C for 4h. It was found that at a temperature of 1050°C, cracks appeared for all three W/B ratios when the GGBFS content was 10% or less. Cracking was significantly reduced as the GGBFS content was increased to 20% or above. It was also found that at elevated temperature (1050°C), compressive strength greatly increased with increasing GGBFS content, especially for the W/B ratio of 0.23. Thus, the fire resistant properties of HPC are greatly improved by the addition of GGBFS. In contrast, GGBFS with a W/B ratio of 0.71 showed no significant increase in compressive strength. At a W/B ratio of 0.23, the clear trend was observed that the optimum GGBFS content for fire resistance is between 50% and 80%. The compressive strength of concrete is more susceptible than the elastic modulus to the effects of elevated temperature. [Copyright &y& Elsevier]

Abstract: The self-propagating high-temperature synthesis (SHS) reactions can take place in Cu–Ti–Si systems with Cu additions of 10–50wt.%, and the products only consist of Ti5Si3 and Cu phases, without any transient phase. In Ti–Si system, most of the Ti5Si3 grains synthesized exhibit the polygon-shaped coarse appearance with an obviously sintered morphology. When Cu content increases from 10 to 50wt.%, however, the Ti5Si3 exhibits cobblestone-like shape with a relatively smooth surface, and its average size decreases significantly from ∼15 to ∼2μm or less. The formation mechanism of Ti5Si3 in Cu–Ti–Si system is characterized by the solution, reaction and precipitation processes. Furthermore, the addition of Cu has a great influence on the volume change between green and reacted preforms. The volume change increases with Cu content increasing from 0 to 20wt.%, and then decreases with the content further increasing from 20 to 50wt.%. The addition of Cu to Ti–Si system significantly decreases the onset temperature of the reaction during differential scanning calorimetry process, which is even much lower than the α→β transition temperature of Ti (882°C), suggesting that the reaction could be greatly facilitated by Cu addition. As a result, the role of Cu serves not only as a diluent but also as a reactant and participates in the self-propagating high-temperature synthesis reaction process. [Copyright &y& Elsevier]

Abstract: The effect of Cr content on the self-propagating high temperature synthesis (SHS) reaction of Cr–Ti–C system has been investigated in this research. The thermodynamics calculation indicates that the TiC possesses higher thermodynamic stability than the Cr23C6, Cr7C3 and Cr3C2 phases, and the formation of TiC is the most exothermic. Additionally, the adiabatic combustion temperature (T ad) decreases with the increase of Cr content except for the phase transition regions. The XRD result shows that the type of products synthesized by SHS changes that a higher Cr content corresponds to higher chromium carbide. When Cr content is 10wt.%, only solid solution (Ti,Cr)Css is formed in the products. When Cr content increases to 20wt.%, besides (Ti,Cr)Css, the Cr7C3 phase is also detected. With the Cr content further increasing to 30 and 40wt.%, the products consist of (Ti,Cr)Css, Cr23C6, Cr7C3 and Cr, and therefore, much higher chromium carbide is synthesized. When Cr content reaches 50wt.%, however, the Cr7C3 disappears and the final products become (Ti,Cr)Css, Cr23C6 and Cr. Moreover, when Cr content increases from 10 to 20wt.%, the lattice parameter of (Ti,Cr)Css decreases, while it increases when the Cr content ranges from 20 to 50wt.%. Furthermore, the microstructure shows that the TiC particulate size decreases from ∼8 to ∼2μm with the increase of Cr content from 10 to 50wt.%, and the morphology shape of TiC particulate becomes more and more spherical. [Copyright &y& Elsevier]

We put forward a novel scheme based on open-loop polarization control (OLPC) to retrieve and preserve arbitrary polarization states endlessly at uniform high speed, with average error of ~ 0.035 rad and time cost less than 300 μ s, which breaks through the limitation of those depend on close-loop polarization control (CLPC). Utilizing perfect modules we build an experimental OLPC system and establish its matrix model with control programme. Results show that the two-unit PC always has blind zone which can not be suppressed to zero, and the blind area centres exactly on the principal state of polarization (PSP) of the second unit. Then we start the third unit to retrieve the SOP from the blind area thus we achieve arbitrary SOPs on the Poincaré sphere endlessly. Subsequently, we demonstrate the great capacity of the OLPC scheme by successfully carrying on retrieving and preserving arbitrary SOPs disturbed by a polarization scrambler, while for sudden and huge disturbance it still shows quite robust and extremely strong. As a result, we fulfill the scheme in practical case of polarization encoded communication system with various environmental disturbance, and further reveal its prominent performance on improvement of signal quality and preservation of reliable communications, which manifests that it is suitable for field applications where exists much disturbance. [ABSTRACT FROM AUTHOR]

Abstract: Renal transplantation is an established treatment for end-stage renal disease. Most renal transplant patients take multiple medications for a long period of time to maintain immunosuppression as well as to treat concomitant chronic diseases. Since some medications prescribed for these patients have narrow therapeutic ranges, optimal pharmacotherapy is vital. However, pharmacists can qualify the role in assisting patients and physicians to solve and reduce drug-related problems. The purpose of this trial was to investigate the effects on treatment outcomes by clinical pharmacists joining renal transplant clinics to provide pharmaceutical care. We enrolled 37 renal transplant patients who visited the renal transplant clinic in our medical center from May 2005 through August 2006. The responsibility of the clinical pharmacist was to interview patients, review medication regimens, and make therapeutic recommendations for 3 hours every Tuesday morning. According to potential clinical impacts, pharmacist recommendations were divided into 6 scales, evaluating physician acceptance of pharmacist recommendations and impact on treatment outcomes. Fifty-five pharmacotherapy recommendations were made for the 37 renal transplant patients during the trial period, of which 81.8% were classified as clinically significant. The drug classes most commonly involved were cardiovascular medications, immunosuppressants, and antimetabolites (32.6%, 23.9%, and 26.1%, respectively). Physician acceptance rates of recommendation types and drug classes were 96.0% and 97.1%, respectively. Among the cases in which the recommendations were accepted, 94.2% of patients showed improved conditions. We concluded that clinical pharmacists joined to renal transplant clinics provide pharmaceutical care with a positive potential impact on physician prescriptions and patient outcomes. [Copyright &y& Elsevier]

Abstract: The SHS reaction behaviors of the Cu–Ti–B4C system with various Cu content were investigated. Theoretical calculation of the adiabatic temperatures reveals that the reaction in the Cu–Ti–B4C system is self-sustainable for the presence of 0–72.22wt.% Cu in the reactants without any preheat. With the increase of Cu content, the adiabatic temperatures, combustion temperatures and wave velocity decrease greatly, while the ignition time shows first a remarkable decrease and then an increase with the minimum value at 20wt.% Cu. Moreover, with the increase of Cu content, the sizes of the TiC and TiB2 grains decrease considerably. [Copyright &y& Elsevier]

Abstract: C particle size plays an important role in the ignition and combustion characteristics of the SHS reaction in the 20wt.% Ni–Ti–C system. When coarse C particles (∼38 and ∼75μm) are used, the SHS reactions consist of two different combustion stages with different brightness intensity of the combustion wave; XRD results indicate that the first and second combustion stages mainly correspond to the formation of Ni–Ti compounds and TiC ceramics, respectively. However, the final reaction is incomplete with a few Ni–Ti compounds and unreacted C. In contrast, when the fine C particle (∼1μm) is used, the SHS reaction consists of only one combustion stage with high brightness intensity of the combustion wave; XRD result indicates that final products consist of TiC and Ni, without any intermediate phase. With the decrease of C particle size, the wave velocities increase, and the ignition time becomes shorter. In addition, the morphology of TiC particulate changes to near-spherical, as C particle size decreases. [Copyright &y& Elsevier]

Abstract: The reaction path of TiC–TiB2 formation in 20 wt.% Cu–Ti–B4C powder mixtures was studied by using differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The Cu–Ti intermetallics (mainly Ti2Cu and TiCu) were formed initially via solid-state diffusion reactions between Cu and Ti particles; and then the Cu–Ti liquids were formed from the eutectic reaction between Ti2Cu and TiCu at about 965°C and the melting of the Ti2Cu. Cu–Ti liquid spread over the B4C and Ti particles, subsequently carbon and boron atoms from the bulk B4C continuously diffuse into the liquid phase to form liquid Cu–Ti–B–C. Finally, TiC and TiB2 particulates precipitate out of the saturated liquid. The exthermic reaction was complete after the addition of Cu. The results showed that Cu not only participated in the reaction, but changed the reaction path between Ti and B4C. [Copyright &y& Elsevier]

Abstract: The effect of Ni content on the products of Ni–Ti–B system via self-propagating high-temperature synthesis (SHS) reaction has been investigated in this research. The results show that the products of SHS reactions consist mainly of TiB2 and Ni. Besides, the transient phases of Ni4B3, Ni3B, NiB and Ni3Ti also exist in the final products, which means the SHS reactions of Ni–Ti–B system are incomplete. The change in the content of Ni within the chosen range from 30 to 70wt.% has little effect on the phase compositions of the final products. However, the sizes of TiB2 particulates have been greatly influenced by the Ni content. The average sizes of normal TiB2 particulates are nearly the same and about 4–6μm when Ni contents are 30, 40 and 50wt.%. Furthermore, TiB2 particulates in the products of these three systems present exaggerated growth and their sizes can even reach 10–15μm. The size of TiB2 particulates decreases dramatically to 1–2μm when Ni content increases to 60wt.% while to 0.6μm or less at 70wt.% Ni. The addition of Ni facilitates to form more liquid phases that are beneficial to TiB2 formation during SHS reaction process. The formation mechanism of TiB2 in Ni–Ti–B system can be characterized by the solution, reaction and precipitation processes. This can be further substantiated by the presence of remaining liquids, the typical hexagonal-prism morphology and the growth striation on (0001) crystal face of TiB2 particulates. [Copyright &y& Elsevier]

Abstract: The effect of Fe addition on the SHS reaction products of Fe–Ti–Si system was investigated. When Fe content is 0wt.%, the product only consists of Ti5Si3. As the Fe content ranges from 10 to 30wt.%, besides Ti5Si3 and Fe phases, the transient Fe2Ti is also found in the final products. With a further increasing Fe content of 40 or 50wt.%, however, in addition to Ti5Si3, Fe and Fe2Ti phases, the FeSi phase is also detected. Furthermore, the contents of Fe2Ti and FeSi phases as well as the solubility of Fe in Ti5Si3 also increase with the increasing of Fe content. This indicates that Fe not only serves as a diluent, but also participates in the SHS reaction process. Moreover, addition of Fe has a great effect on the microstructures of SHS reaction products. When Fe content is 10 or 20wt.%, the Ti5Si3 exhibits cobblestone-like shape. When Fe content is increased to 30wt.%, the Ti5Si3 particulates are finer and most of them are surrounded by the bonding agents. As the Fe content is further increased to 50wt.%, it is difficult to distinguish Ti5Si3 particulates from Fe and its compounds. The Ti5Si3 particulate sizes decrease from more than 6 to about 0.6μm or less when Fe content in the preforms ranges from 10 to 50wt.%. This is mainly due to the fact that the combustion temperature decreases with the increasing of Fe content. The addition of Fe provides more liquid phase for the Ti5Si3 formation during SHS reaction process. The formation mechanism of Ti5Si3 in Fe–Ti–Si system can be characterized by the solution, reaction and precipitation processes. This can be confirmed by the presence of bonding agents (remaining liquids), nearly spherical (cobblestone-like) morphology and relatively smooth surface of Ti5Si3 particulates, as well as the presence of growth striation on the surface of Ti5Si3 particulates. [Copyright &y& Elsevier]

Abstract: The solidification behavior of the cast TiB2 particulate reinforced AZ91 composite, including the cooling curve, microstructure and grain refinement effect, was investigated in the present study. Compared with the AZ91 alloy, the composite possessed lower nucleation temperature of primary α-Mg, almost the same eutectic reaction temperature and faster cooling rate during the total solidification time. The TiB2 particulates were pushed into the last solidified region and were surrounded by the eutectic Mg17Al12. The grain refinement effect in the TiB2/AZ91 composite can be attributed to the growth restriction effect exerted by TiB2 particulates and the faster cooling rate of the composite. [Copyright &y& Elsevier]