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Laser-induced breakdown spectroscopy (LIBS) has been proven to be an effective way for online analysis of coal properties (such as ash content, volatile content, and calorific value), but the quantitative analysis accuracy still needs to be improved. Herein, a polarization spectral data fusion scheme was proposed to obtain more abundant spectral information and improve the performance of quantitative analysis models. First, the polarization effect of laser-induced coal plasma emission was analyzed using the Stokes parameters of the average spectra. Due to the partially polarized phenomenon of emission, fused data of PRLIBS (0°, 0) (horizontal plasma polarization spectra) and PRLIBS (90°, 0) (vertical plasma polarization spectra) was utilized to establish an efficient prediction model to obtain high prediction accuracy. For fusion models, the root mean square error prediction (RMSEP) of ash content, volatile content and calorific values were 1.497%, 0.595%, and 0.597%, respectively, and the coefficients of determination (R2) were 0.980, 0.968, and 0.978, respectively. Comparison with regression models for individual PRLIBS (0°, 0), PRLIBS (90°, 0), and LIBS data, the data fusion scheme significantly improved the performance of the prediction model. The improvement in model performance is due to the fact that there is no perfect correlation between PRLIBS (0°, 0) and PRLIBS (90°, 0), whilst polarization spectral fusion makes it possible to acquire more number of characteristic spectral lines with high importance score. The results demonstrated the feasibility of PRLIBS spectral fusion to provide better analytical results for ash content, volatile content, and calorific values of coal. [Display omitted] • The application of plasma polarization spectra in the quantitative analysis of coal properties is introduced. • The polarization effect of laser-induced coal plasma emission is analyzed using the Stokes parameters of the average spectra. • A polarization spectrum data fusion scheme is proposed to improve the performance of the quantitative analysis model. [ABSTRACT FROM AUTHOR]

The isothermal sections of the phase diagram and the liquid projection of the Ti-Al-Nb ternary system as well as the phase transformations of a Ti-46.5Al-16.5Nb alloy were calculated using Pandat software. The solidification sequence and subsequent phase transformations of the alloy were verified by microstructural observations and thermo-analysis (TA). The tie-triangle of the three-phase region of α + β + γ at 1300 °C and the tie line of the α and β phases at 1400 °C were identified using electron probe microanalysis (EPMA). Neither the phase equilibria of the α, β and γ phases at 1300 °C nor the tie line of the α and β phases at 1400 °C are in agreement with the calculated phase diagrams reported in the literature. The solidification sequence and subsequent solid-state phase transformations of this alloy were determined as follows: liquid → liquid + β → β → α + β → α + β + γ → β + γ (The β phase and the B2 phase were not differentiated in the present paper.) The phase transformation temperatures were also measured by differential scanning calorimetry (DSC). [ABSTRACT FROM AUTHOR]

The ordered ω phase in as-cast Ti-45Al-8.5Nb-0.2B alloy and its phase transformation during heat treatment are investigated. Ordered ω variants are observed to uniformly precipitate within the β o area in as-cast Ti-45Al-8.5Nb-0.2B alloy. After annealing at 850 °C for 500 h, the β o areas are replaced by large B8 2 -ω o grains. Small γ precipitates are observed at the grain boundaries of the ω o phase and are thought to be transformed from the β o phase. Moreover, the ω o precipitates directly transformed from the parent α 2 laths are found within the lamellar colonies. The orientation relationship between the ω o phase and the lamellar structure is < 110] γ //[0001] ωo //[11 2 ¯ 0] α2 ; (111) γ //(11 2 ¯ 0) ωo //(0001) α2 . The interfaces between the ω o and γ are semi-coherent. The ω o phase is an equilibrium phase at 850 °C in high Nb-containing TiAl alloys. When annealed at 1250 °C, the ordered ω is eliminated in a short time, and the β o phase is substituted by the coarsened α 2 laths in the lamellar colonies after 12 h annealing. [ABSTRACT FROM AUTHOR]

The transformation of the D0 19 - α 2 phase to the B8 2 - ω o phase is a new type of phase transformation in high Nb-containing TiAl alloys; experimental results concerning this phase transformation are still lacking. Moreover, studies on the orientation relationships (ORs) between these two phases are scarce compared with those reported between the disordered ω and α phases, which can be more complicated due to their ordered structures. In this study, the direct α 2 to ω o phase transformation is observed by transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). The ω o phase is transformed from the α 2 laths in the lamellar structure after annealing over long periods at 850 °C. The various ORs observed between these two phases can be merged into two typical ORs: [ 1 1 2 ¯ 0 ] α 2 / / [ 0 0 0 1 ] ω o , ( 0 0 0 2 ) α 2 / / ( 1 1 2 ¯ 0 ) ω o and [ 1 1 ¯ 0 0 ] α 2 / / [ 2 2 4 ¯ 3 ¯ ] ω o , ( 0 0 0 2 ) α 2 / / ( 0 1 1 ¯ 2 ) ω o . The other ORs observed are subsets of these two ORs. The edge-to-edge matching model is applied to predict the possible ORs between the ordered α 2 and ω o phases based on the calculated close-packed planes of the two phases. The simulation results agree well with the experimental results. [ABSTRACT FROM AUTHOR]

Bamboo processing is faced with increasing requirements of resource reusability in China. A large amount of waste bamboo green produced in bamboo processing needs to be recycled. Waste bamboo green contains a large number of environmentally friendly wax components. In this study, supercritical CO 2 extraction was used to extract bamboo green waste to obtain natural wax. Response surface methodology (RSM) was used to optimize the extraction process and the yield of bamboo green wax under pressure of 20–30 MPa, temperature of 318–328 K, and time of 30–90 min. The extracted bamboo green wax was characterized by gas chromatography and mass spectrometry (GC-MS). RSM optimization shows that under the conditions of 26 MPa, 328 K, and 56 min, the yield of bamboo green wax was the highest at 2.327%. The compositions of esters, fatty acids, sterols and so on in bamboo green wax were characterized by GC-MS. Differential scanning calorimetry (DSC) shows that the melting point of bamboo green wax is 334 K. At last, the economic evaluation of bamboo green wax was made to analyze its potential application prospect. It is supposed that bamboo green waste is a resource for natural wax with potential application value. [ABSTRACT FROM AUTHOR]

High Nb containing TiAl alloys have prospect to be used for turbo wheel and exhaust valve for vehicle engine. Friction welding is a suitable process for fabricating these components. For investigating the weldability of these alloys, cylindrical samples of Ti–45Al-8.5Nb-0.2W-0.2B-0.02Y (in at%) alloy with a diameter of 10 mm were welded by continuous drive friction welding process, and the microstructures and the mechanical properties of the joints were analyzed in this paper. The results showed that the weldability of the present alloy was very good. At parameters of rotational speed of 2400 r/min, friction pressure of 320 MPa, burn-off distance of 3 mm and upset pressure of 360 MPa, completely metallurgical bonding interfaces were obtained. The joint had a severely plastic deformation zone (SPDZ) with a biconcave lens geometry. The thicknesses of the center and periphery of SPDZ were about 40 μm and 800 μm, respectively. There existed a transition zone (TZ) between parent metal (PM) and SPDZ. SPDZ exhibited the deformation flow lines and had a randomly-oriented recrystallized duplex (DP) microstructure with the average grain size of 2.5 μm, in contrast, PM presented a nearly lamellar (NL) microstructure with a colony size of 150 μm. TZ showed a mixture microstructure combining deformed lamellar colonies and partially recrystallized grains. At room temperature, 750 °C and 800 °C, welding joints had better tensile properties than PM. • As-cast Ti–45Al-8.5Nb-0. 2W-0. 2B-0. 02Y alloy has good friction weldability. • The joint had a severely plastic deformation zone with a biconcave lens geometry. • Fine-grained DP microstructure of welding joint showed random orientation. • Welding joint had better tensile properties than parent metal. [ABSTRACT FROM AUTHOR]

The cyclic stress-strain (CSS) behavior of high Nb containing TiAl alloy with a duplex microstructure was investigated at 850 °C. Transmission electron microscope (TEM) observations and electron backscattered diffraction (EBSD) techniques were carried out to obtain insight into the microstructure evolution governing this behavior. At low strain amplitude, the material exhibits a rapid saturation of stress amplitude. At intermediate and high strain amplitude, the CSS behavior is characterized by generally cyclic softening. The changes of microstructure are strain-induced phase transformations and dynamic recrystallization, which lead to a degradation of lamellar microstructure. Twin boundaries can promote discontinuous dynamic recrystallization of γ phase, for processing relatively high energy. α 2 + γ → B2, α 2 → B2, and α 2lamellae → γ phase transformations are detrimental to fatigue life of the material, because fracture propagation are usually along B2 phase boundaries and γ grain boundaries, thus, the fracture mode is a combination of ductile fracture and intergranular cleavage fracture. [ABSTRACT FROM AUTHOR]

Clozapine is an atypical antipsychotic drug used in the treatment of schizophrenia, which has been shown to reverse behavioural and dendritic spine deficits in mice. It has recently been shown that deficiency of 14-3-3ζ has an association with schizophrenia, and that a mouse model lacking this protein displays several schizophrenia-like behavioural deficits. To test the effect of clozapine in this mouse model, 14-3-3ζ KO mice were administered clozapine (5 mg/kg) for two weeks prior to being analysed in a test battery of cognition, anxiety, and despair (depression-like) behaviours. Following behavioural testing brain samples were collected for analysis of specific anatomical defects and dendritic spine formation. We found that clozapine reduced despair behaviour of 14-3-3ζ KO mice in the forced swim test (FST) and altered the behaviour of wild types and 14-3-3ζ KO mice in the Y-maze task. In contrast, clozapine had no effects on hippocampal laminar defects or decreased dendritic spine density observed in 14-3-3ζ KO mice. Our results suggest that clozapine may have beneficial effects on clinical behaviours associated with deficiencies in the 14-3-3ζ molecular pathway, despite having no effects on morphological defects. These findings may provide mechanistic insight to the action of this drug. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bamboo green residues were fermented by lactic acid bacteria under different days. • Fermented residues can produce self-adhesive substances to making particleboard. • Particle shape and fermentation time affect binderless particleboard properties. • Binderless particleboard is a kind of green way to recycle bamboo green waste. In this study, a new type of binderless particleboard was prepared from bamboo green residues processed by biological fermentation. Bamboo green residues were fermented using lactic acid bacteria microorganisms, and binderless bamboo particleboards were prepared by hot pressing. The effects of the fermentation time on the morphological characteristics and chemical components of the residues were investigated. Further, the vertical density profile, internal bonding, and other physical and mechanical properties of the binderless bamboo particleboard were examined. The results revealed that the slenderness ratio of flakes decreased at first and then increased with an increase in the fermentation time (in days), and the chemical components of the bamboo green residues degraded with time. The features of the fermented flakes affect the performance of the prepared particleboard. The physical and mechanical properties of the binderless bamboo particleboards prepared from fine residues obtained after 7 days of fermentation were better than those prepared using the coarse and mixed groups, and met the requirements of the chinese standard GB/T4897-2015. This novel preparation method of binderless bamboo particleboard is helpful to develop a new eco-friendly building material. [ABSTRACT FROM AUTHOR]

Abstract: CALPUFF is an atmospheric source-receptor model recommended by the US Environmental Protection Agency (EPA) for use on a case-by-case basis in complex terrain and wind condition. As the bulk of validation of CALPUFF has focused on long-range or short-range but long-term dispersion, we can not gauge the reliability of the model for predicting the short-term emission in near-field especially complex terrain, and sometimes this situation is important for emergency emission. To validate the CALPUFF’s application in such condition, we carried out a tracer experiment in a near-field complex terrain setting and used CALPUFF atmospheric dispersion model to simulate the tracer experiment in real condition. From the centroid trajectory comparison of predictions and measures, we can see that the model can correctly predict the centroid trajectory and shape of tracer cloud, and the results also indicate that sufficient observed weather data only can develop a good wind field for near-field. From the concentration comparison in each arc, we can see the model underestimate horizontal extent of tracer puff and can not reflect the irregular characters showed in measurements. The result of global analysis is FOEX of −25.91%, FA2 of 27.06%, FA5 of 61.41%. The simulations shows that the CALPUFF can simulate the position and direction of tracer cloud in near-field complex terrain but underestimate over measurements especially in peak concentrations. [Copyright &y& Elsevier]

The enhanced laser induced breakdown spectroscopy is highly desirable for the quantitatively detection with low limit of detection (LOD) and high accuracy. Higher enhancement factor is always obtained from discharge assisted laser-induced breakdown spectroscopy with enough higher energy injection in comparison to the normally standard laser induced breakdown spectroscopy (LIBS), which means dangerous with high voltage and elevated power. Here, a low power (10 W) injected unipolar discharge arc is proven to greatly enhance the LIBS with a large enhancement factor up to 13.8 when the discharged electric arc followed by a laser induced plasma are simultaneously applied on a silicon wafer, which is comparative or larger than those results with high-power (kW) and high voltage (kV) being applied. Furthermore, the enhanced technique is applied on an actual qualitative detection of cadmium in soil. The lines of Cd II (214.44 nm) from soil is enhanced as compared to a LIBS measurement. Accordingly, the LOD of the typical emission line is reduced to 23.5 ppm by the unipolar discharge arc assisted laser induced breakdown spectroscopy (UD-LIBS), which is 2.45-fold lower than that from the normal LIBS. The pre-ionization of the environment and the surface by the modulated discharge arc to directly make the Inverse Bremsstrahlung (IB) absorption with higher absorption coefficient dominate the initial stage of plasma formation rather than the multi-photon absorption process, thus make both electron density and the temperature of plasma raising are the main mechanism of spectral enhancement, which is further proved by the evolution dynamics images of two plasma overlapping processes under an in-situ intensified charge-coupled device (ICCD) based photographic system. The simple, portable, commercial highly enhancement way is greatly benefit to the actual applications. Unlabelled Image • A low-power unipolar discharge arc is utilized to enhance the LIBS signal. • UD-LIBS technique is used for qualitative detection of cadmium in soil. • The enhancement mechanism is the absorptivity of reverse bremsstrahlung rising due to the assisted discharge arc. [ABSTRACT FROM AUTHOR]

It is shown that a uniform and refined fully lamellar microstructure can be generated by tempering the quenched samples in the single α region of as-forged Ti–43Al–9V–Y alloy. The refining effect was mainly connected with the quenched microstructures especially for their substructure, grain size and the residual β particles after the quenching. A series of β-decomposed products: martensite plate, massive α and coarsened α lath with increasing grain size were produced due to the decreasing cooling rate during the wedge-shaped sample quenched into iced brine. In addition, the decomposition of β directly to γ has also been observed during the quenching with different cooling rate. The lamellar colony size can be controlled in the range of 25–50 μm after tempering. • Uniform and refined fully lamellar structure can be obtained by quenching and tempering. • The β-decomposed product varies from martensitic α plate, massive α to coarsened α lath with decreasing quenching rate. • The lamellar colony size after tempering is mainly connected with the quenched microstructures. [ABSTRACT FROM AUTHOR]

Brain-derived neurotrophic factor (BDNF) and the Val66Met polymorphism may play a role in the development of psychosis and schizophrenia. The aim of this study was to investigate long-term effects of methamphetamine (Meth) on psychosis-like behaviour and dopamine receptor and dopamine transporter gene expression in a novel rat model of the BDNF Val66Met polymorphism. At the end of a 7-day subchronic Meth treatment, female rats with the Met/Met genotype selectively showed locomotor hyperactivity sensitisation to the acute effect of Meth. Male rats showed tolerance to Meth irrespective of Val66Met genotype. Two weeks later, female Met/Met rats showed increased locomotor activity following both saline treatment or a low dose of Meth, a hyperactivity which was not observed in other genotypes or in males. Baseline PPI did not differ between the groups but the disruption of PPI by acute treatment with apomorphine was absent in Meth-pretreated Met/Met rats. Female Met/Met rats selectively showed down-regulation of dopamine D2 receptor gene expression in striatum. Behavioural effects of MK-801 or its locomotor sensitisation by prior Meth pretreatment were not influenced by genotype. These data suggest a selective vulnerability of female Met/Met rats to short-term and long-term effects of Meth, which could model increased vulnerability to psychosis development associated with the BDNF Val66Met polymorphism. • Methamphetamine (Meth) was administered for 7 days in BDNF Val66Met rats. • Locomotor hyperactivity sensitisation on Day 7 only in female Met/Met rats. • Apomorphine disruption of PPI absent in Meth-pretreated Met/Met rats. • Dopamine D2 receptor downregulation in striatum of female Met/Met rats. • BDNF Val66Met may increase vulnerability to psychosis development in females. [ABSTRACT FROM AUTHOR]

Diagnosis of inflammation in the blood requires multiple medical examinations that rely heavily on doctors' experiences, which offer a large room for error. Thus, diagnosis becomes complex and time consuming. Herein, we proposed the use of laser-induced breakdown spectroscopy (LIBS) and chemometric methods to rapidly and accurately diagnose inflammation in blood. Serum samples were collected from 10 healthy people and 10 patients suffering from inflammation in blood. The training and test sets were divided according to each individual in a ratio of 7:3. After excluding considerably different divisions of training and test sets (DTTs) using the Wilcoxon test, 10 DTTs were randomly selected. With these 10 DTTs, backpropagation neural network (BPNN) models were built for substrate optimization, and glass slides exhibited the best performance with an average accuracy of 80.87%. Using glass slides and a multiplicative scatter correction–mean impact value–backpropagation neural network (MSC–MIV–BPNN) model, the accuracy of the best DTT was improved to 93.00%. For the identification effect validation of the improved model, the same features were selected from other DTTs to build new MSC–MIV–BPNN models. The accuracies of all the DTTs were increased by 4.67%–16.33% compared to the original BPNN models. Furthermore, the validation time of a single DTT was ∼0.7 s. These results demonstrated that LIBS combined with the MSC–MIV–BPNN model could accurately and rapidly identify samples with inflammation in blood from healthy blood samples for emergency applications. [Display omitted] • The training and test sets were divided according to each individual. • Significant differences between training and test sets were tested by Wilcoxon test. • The average accuracy was improved from 59.13% to 80.87% by substrate optimization. • With multiple scattering correction and mean impact value methods, the accuracies were improved by 4.67% to 16.33%. [ABSTRACT FROM AUTHOR]

Abstract: The hot deformation behavior of Ti–45Al–8.0Nb–0.2B–0.2W–0.02Y(at.%) alloy was studied by simulating isothermal forging tests using 6mm diameter and 10mm height compressive specimens in order to find the appropriate deformation processing parameters. The seven deformation temperatures of 900, 1000, 1050, 1100, 1150, 1200 and 1250°C and three deformation strain rates of 5×10−4, 1×10−3 and 5×10−2 s−1 were used in the present investigation. The experimental results showed that the deformation resistance decreased and the true stress vs. true strain curves became flatter with the decrement of strain rate at the same deformation temperatures. However, the deformation resistance decreased with increasing temperature, and the sensitivity of true stress to strain rate became smaller as temperature increased at the same deformation strain rates of 5×10−2, 1×10−3 or 5×10−4 s−1. This indicates that the higher the deformation temperature and the lower the strain rate, the smaller the deformation resistance, which means that the high deformation temperature and low strain rate are beneficial to the hot deformation of high Nb containing TiAl alloys. Using the kinetic rate equation the stress exponent n and the apparent activation energy Q were determined as 4.7 and 366.5kJmol−1, respectively. Considering the durability limit of the forging machine and mold materials for deformation temperature and the deformation microstructure control depending on the deformation degree and ending deformation temperature, an appropriate set of deformation processing parameters of 1250°C and 1×10−3 s−1 are recommended for the present TiAl alloy. These recommended hot deformation processing parameters have been successfully used for the quasi-isothermal canned forging of high Nb containing TiAl alloy billets with the initial dimension of 120mm in diameter and 180–350mm in height. [Copyright &y& Elsevier]

• The cyclic behavior and microstructure evolution of TC4F alloy were investigated. • Phase transformations and α dynamic recrystallization contributed to great changes in the microstructure of TC4F alloy. • The evolution of substructure played an important role in the dwell-fatigue of TC4F alloy. The cyclic behavior and microstructure evolution of Ti-6Al-4V-0.55Fe alloy were investigated with three different total strain amplitudes. A slight softening was occurred with Δ ε t /2 = 1.20%, and the alloy mainly suffered α recrystallization. Besides, a gentle softening can be observed with Δ ε t /2 = 1.60%, which led to more substructure deformation. Furthermore, a sudden drop of the stress amplitude was occurred with Δ ε t /2 = 4.00% which resulted in more plastic deformation. The phase transformation and α recrystallization were observed. Cracks were propagated along the α grain boundaries and the α/β lamellar interfaces due to the concentrated dislocations at the α/β lamellar interfaces. [ABSTRACT FROM AUTHOR]

The high dynamic range imaging (HDRI) technology can realistically reproduce the scene and acquire more image information for analysis and processing. In this paper, a defect detection method based on HDRI is proposed to solve the visual inspection problem of industrial parts with high-reflective surface. Firstly, a fast calibration method is put forward to increase the calibration speed of the camera response function (CRF). Then, a novel algorithm named adaptive tone mapping based on color correction model in gradient domain is designed to adaptively adjust image chromaticity information. Finally, adaptive threshold segmentation and Haar-like feature extraction algorithm are used to detect surface defects in synthesized high dynamic range (HDR) images. The experimental results show that the HDR images processed by our algorithm can meet the detection requirements for high-reflective-metal surface. The number of sampling points required by our fast calibration algorithm of CRF is 1/10 times than that of the traditional algorithm, and the running time in the program is about 1/4 times than that of the traditional algorithm. What's more, our improved local tone mapping algorithm is obviously improved in information entropy, contrast and average gradient. [ABSTRACT FROM AUTHOR]