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In this paper, we reported on the magnetic properties and magneto-caloric effect (MCE) of the aluminium compounds Dy 2 CuAl 3 and Tm 2 CuAl 3 based on the magnetization and isothermal magnetization of various temperature measurements. Both compounds obey magnetic phase transition from a paramagnetic (PM) to ferromagnetic (FM) state (second order) around the Curie temperatures of T C  ∼ 24.5 and 4.7 K together with a considerable reversible MCE for Dy 2 CuAl 3 and Tm 2 CuAl 3 , respectively. The magnetic entropy change (-Δ S M ) and the relative cooling power ( RCP ) were estimated and discussed in terms of MCE. Maximum values of -Δ S M are 6.68 and 11.33 J/kg K for Dy 2 CuAl 3 and Tm 2 CuAl 3 , respectively, for a change in field of 0–5 T. Correspondingly, the values of RCP are 364 J/kg and 216 J/kg. [ABSTRACT FROM AUTHOR]

Y 2 O 3 transparent ceramics were fabricated from precipitated powders prepared at different stirring speeds during the precipitation process. The influence of the stirring speed on the phase component of precursors, morphology of Y 2 O 3 powders and properties of fabricated ceramics were systematically investigated. Crystalline phase precursors of (NH 4 ) a Y(OH) b (CO 3 ) c ·H 2 O were prepared from 110 rpm, 220 rpm and 550 rpm respectively. But amorphous precursors of Y(CO 3 )(OH)·nH 2 O (n = 1–1.5) were observed when stirring speeds were 330 rpm and 440 rpm. Y 2 O 3 powders prepared from 440 rpm exhibited the lowest agglomeration and the smallest grain size, and the ceramics with the optimal transmittance was accordingly obtained. The results of computational fluid dynamics software CFX showed that a more homogeneous flow field distribution without local circulations could be produced at 440 rpm, which would be benefit for the optical quality of transparent ceramics. The study would provide a considerable reference for the controllable fabrication of well-dispersibility Y 2 O 3 powders and Y 2 O 3 transparent ceramics. [ABSTRACT FROM AUTHOR]

The glass forming ability, magnetism and magneto-caloric effect have been investigated in Er 60 Ni 30 Co 10 melt-spun alloy by using X-ray diffraction, differential scanning calorimetry and magnetization measurements. The amorphousized Er 60 Ni 30 Co 10 exhibits a relatively wide supercooled liquid region of 40 K and a second-order ferromagnetic transition around Curie temperature of 11.5 K. Under Δ Η (magnetic field change) of 0–5 T, the values of −Δ S M max (maximum magnetic entropy change) and RCP (relative cooling power) are 12.1 J/kg K and 342 J/kg, respectively. Furthermore, the field dependence of the magnetic entropy change for Er 60 Ni 30 Co 10 obeys the phenomenological universal curve and corresponds to a field independent exponent of n  = 0.58 ± 0.03. [ABSTRACT FROM AUTHOR]

In this paper, Cu-based and Ni-based filler metals were used to obtain laser-CMT hybrid welded copper/stainless steel (Cu/SS) joints. The effect of wire compositions on the microstructure and mechanical properties of T2 Cu/304 SS dissimilar metal joint was studied. The results showed that Fe–Cu liquid phase separation occurred in the fusion zone of the Cu-based weld, and Cu penetration cracks appeared in the heat-affected zone (HAZ) on the steel side. The Cu penetration cracks formation is derived from supersaturated Cu atoms penetrating, gathering and merging at the steel side fusion line along the austenite grain boundaries. The penetration cracks can be eliminated effectively by the Ni-based filler metal, because the diffusion of Cu into the fusion zone and the HAZ on the steel side is limited significantly by the increase of Ni content. The Ni-based weld consisted of dendrite grains in the fusion zone, and Fe-rich blocks and Ni-rich islands nearby the HAZ of Cu-side. • Defect-free weld was obtained by laser-CMT hybrid welding with Ni-based wire. • Cu-based weld penetration cracks mechanism was illustrated. • The microstructures of Cu-based and Ni-based welds were compared. • The mechanism of inhibition of penetration cracks in Ni-based weld was discussed. [ABSTRACT FROM AUTHOR]

Rare earth (RE) based RE - TM - X (TM = transition metal elements; X = P - block elements) materials have received continuous attention due to the exhibition of various intriguing magnetic functional characteristics. In this work, a combined experimental and theoretical investigation has been conducted in detail for RE Co 12 B 6 (RE = Ce, Pr, Nd) compounds with regard to their structural and magnetic properties, particularly the magnetocaloric effect and magnetic phase transition (MPT). All of the present RE Co 12 B 6 compounds are found to crystalize in the SrNi 12 B 6 -type structure and with a ferrimagnetic ground state, which is confirmed by density functional theory calculations and magnetization measurements. The magnetic moments of RE atoms and Co atoms tend to be in antiparallel alignment, and the MPT of these materials originates primarily from the spin-polarized 3 d electrons of the Co atoms, which can be greatly affected by the 4 f electrons of RE atoms. Considerable magnetocaloric effects have been observed around its own T C of 130, 157, and 160 K, for CeCo 12 B 6 , PrCo 12 B 6 , and NdCo 12 B 6 , respectively, which is related to a typical second-order MPT. The corresponding maximum magnetic entropy change and relative cooling power values,with field changes of 0–70 kOe, are determined to be 2.54, 2.84, and 2.77 J/kg K and 116.8, 156.2, and 155.1 J/kg, respectively. The MPT properties of present RE Co 12 B 6 compounds were studied in further detail by critical analysis using the modified Arrott Plot and Kouvel-Fisher methods, which can be explained within the frame of the 3D Heisenberg model with short-range magnetic interaction. [Display omitted] [ABSTRACT FROM AUTHOR]

The magnetic properties and magnetocaloric effect (MCE) in dysprosium zinc binary DyZn compound were studied. The compound reveals a paramagnetic-to-ferromagnetic transition together with a spin reorientation phenomenon at Curie temperatures of T C ∼135 and T SR ∼50 K, respectively. A large reversible MCE was observed in DyZn around T C . For the magnetic field change of 0–7 T, the values of maximum magnetic entropy change (–Δ S M max ), relative cooling power ( RCP ), and refrigerant capacity ( RC ) were 12.2 J/kg K, 895 J/kg, and 672 J/kg, respectively. [ABSTRACT FROM AUTHOR]

Tungsten disulfide (WS 2 ) has recently emerged as a narrow-band visible-light-driven photocatalyst; however, high recombination of photo-induced electrons and holes becomes a major concern to advance its photocatalytic performance. Here we for the first time adopt manganese oxide (MnO x ) as a hole-trapping material to decorate WS 2 nanosheets by photo-deposition in MnSO 4 solution. The MnO x decorated WS 2 (MnO x /WS 2 ) is found to exhibit more negative flat band potential, lower impedance and higher photocurrent response compared with pure WS 2 . These features beneficial to charge transfer and separation render the MnO x /WS 2 nanosheets highly active and visible-light-driven photocatalyst in RhB degradation. Further, the hole-trapping function of MnO x in promoting efficient charge separation of MnO x /WS 2 is experimentally demonstrated. [ABSTRACT FROM AUTHOR]

The synergism of CeO 2 on the flame retardancy and char-forming mechanism of efficient intumescent flame retardant polypropylene composites (PP/IFR) are investigated. It is found that CeO 2 enhances the limited oxygen index (LOI) value of the PP/IFR composites dramatically and the materials pass the vertical burning test (UL-94) V-0 rating test. The catalytic effectivity (CAT-EFF) results show that when 1 wt% CeO 2 is introduced into PP/IFR composite, it has the highest CAT-EFF, and the LOI value of the composites increases from 27.1 to 32.6%. The presence of CeO 2 enhances the fire retardant performance, resulting consequently in a great reduction in peak heat release rate (p-HRR), total heat release (THR), heat release capacity (HRC) of the PP/IFR composite obtained from microscale cone calorimeter (MCC) tests. CeO 2 reduces the initial decomposition temperature of the IFR and PP/IFR, and it improves the thermal stability and char formation ability. When CeO 2 is incorporated into IFR, it forms numerous closed foams without holes, and the char contains more P. The morphological structures observed by digital photos and scanning electron microscopy (SEM) demonstrated that CeO 2 promotes to form the more continuous and more compact intumescent char layer. The Energy dispersive X-ray spectrometry (EDX) results indicate that it remains more P and O elements for PP/IFR/1%CeO 2 composite. The Laser Raman spectroscopy (LRS) measurements reveal that the strength of the char residue with CeO 2 is enhanced with lower R value. The X-ray photoelectron spectroscopy (XPS) analysis demonstrates that CeO 2 helps to form crosslinking network containing more O and P in the char layer. Thus, a suitable amount of CeO 2 plays a critical role in the flame retardancy and char-forming behavior of PP/IFR, and promotes the formation of more compact char structures in the PP/IFR composites. [ABSTRACT FROM AUTHOR]

The influence of a weak transverse magnetic field on the morphology and orientation of Al 3 Ni dendrites in directionally solidified Al-12 wt% Ni alloys was investigated. The experimental results indicated that the magnetic field caused segregation. It was also found that the application of a magnetic field decreased the primary dendrite spacing. By means of electronic backscatter diffraction (EBSD) analysis, the orientation of the Al 3 Ni dendrite was studied. In the case of no magnetic field, the 〈010〉 crystal direction of the Al 3 Ni crystal was oriented along the solidification direction. When a transverse magnetic field was applied, the 〈001〉 crystal direction rotated to the magnetic field direction, whereas the 〈010〉 crystal direction remained oriented along the solidification direction. The above experimental results are discussed in the context of thermoelectric magnetic convection (TEMC) and crystal anisotropy. [ABSTRACT FROM AUTHOR]

The effect of a transverse magnetic field on the growth of equiaxed grains during directional solidification of Al-10wt% Cu alloys was investigated experimentally and numerically. The experimental results show that the magnetic field has a great influence on the size and distribution of equiaxed grains. Indeed, the magnetic field causes refined and coarsen equiaxed grains to distribute on the both sides of the sample, respectively. In-situ synchrotron X-ray imaging shows that a transverse magnetic field induced some force which can act on equiaxed grains and cause the movement of equiaxed grains during directional solidification. Numerical results reveal that the modification of the structure may be attributed to the thermoelectric (TE) magnetic effects produced by the magnetic field. Furthermore, a new method of removing inclusions in molten metal is developed by means of the TE magnetic force. [ABSTRACT FROM AUTHOR]

Background: Studies on the relationship between thyroid function and non-alcoholic fatty liver disease (NAFLD) among euthyroid subjects have produced conflicting results.Objectives: The aim of this study was to investigate the association between thyroid function and the presence of NAFLD in a large-sample middle-aged euthyroid subjects.Methods: A total of 2576 euthyroid subjects who underwent health check-up were included. NAFLD was diagnosed by hepatic ultrasonography. Conventional risk factors for NAFLD were assessed as well as serum levels of TSH, FT3 and FT4.Results: Levels of FT3 were significantly higher in NAFLD group (5.12 ± 0.58 versus 4.84 ± 0.58 pmol/L, adjustedp = 0.000) than non-NAFLD group, while levels of TSH and FT4 were comparable between NAFLD and non-NAFLD groups (TSH: 2.13 ± 0.90 versus 2.20 ± 0.93 mIU/L, adjustedp = 0.190; FT4: 16.41 ± 2.04 versus 16.18 ± 2.06 pmol/L, adjustedp = 0.146, respectively). Levels of FT3 were positively correlated with components of metabolic syndrome. Multivariate logistic regression analysis revealed that high level of FT3 was an independent predictor for NAFLD (odds ratio: 1.253,p = 0.040). The relationship between FT4 and NAFLD in women was different according to menopausal status, with negative association in pre-menopausal women (OR: 0.777, 95% CI: 0.617–0.979,p = 0.032) and null association in post-menopausal women (OR: 1.037, 95% CI: 0.841–1.277,p = 0.736).Conclusions: Our findings suggested that high levels of FT3 were significantly associated with NAFLD among middle-aged euthyroid subjects independently of known metabolic risk factors. A negative correlation of serum FT4 level with NAFLD was only observed in pre-menopausal women. [ABSTRACT FROM AUTHOR]

• A ultiscale reweighted convolutional coding neural network (MRCON-Net) for reducing artifact noise in low-dose CT imaging is proposed. • In this work, w extend traditional CSC to its reweighted convolutional learning form. Furthermore, we use dilated convolution to extract multiscale image features, which allows our single model to capture the correlations between features of different scales. • To automatically adjust the elements in the feature code to correct the obtained solution, channel attention is utilized to learn appropriate weights. Low-dose computed tomography (LDCT) has become increasingly important for alleviating X-ray radiation damage. However, reducing the administered radiation dose may lead to degraded CT images with amplified mottle noise and nonstationary streak artifacts. Previous studies have confirmed that deep learning (DL) is promising for improving LDCT imaging. However, most DL-based frameworks are built intuitively, lack interpretability, and suffer from image detail information loss, which has become a general challenging issue. A multiscale reweighted convolutional coding neural network (MRCON-Net) is developed to address the above problems. MRCON-Net is compact and more explainable than other networks. First, inspired by the learning-based reweighted iterative soft thresholding algorithm (ISTA), we extend traditional convolutional sparse coding (CSC) to its reweighted convolutional learning form. Second, we use dilated convolution to extract multiscale image features, allowing our single model to capture the correlations between features of different scales. Finally, to automatically adjust the elements in the feature code to correct the obtained solution, a channel attention (CA) mechanism is utilized to learn appropriate weights. The visual results obtained based on the American Association of Physicians in Medicine (AAPM) Challenge and United Image Healthcare (UIH) clinical datasets confirm that the proposed model significantly reduces serious artifact noise while retaining the desired structures. Quantitative results show that the average structural similarity index measurement (SSIM) and peak signal-to-noise ratio (PSNR) achieved on the AAPM Challenge dataset are 0.9491 and 40.66, respectively, and the SSIM and PSNR achieved on the UIH clinical dataset are 0.915 and 42.44, respectively; these are promising quantitative results. Compared with recent state-of-the-art methods, the proposed model achieves subtle structure-enhanced LDCT imaging. In addition, through ablation studies, the components of the proposed model are validated to achieve performance improvements. [ABSTRACT FROM AUTHOR]

Highlights: [•] We revealed the TLDZ in the LHWD retained active during ca. 43–23Ma. [•] We discussed the Cenozoic evolution of the TLFZ in the LHWD. [•] We discussed the driving mechanism of the TLFZ in early Cenozoic. [Copyright &y& Elsevier]

• R. pseudoacacia increased the fine particles and reduced coarse particles content. • R. pseudoacacia significantly reduced D 0 , D 1 , D 2 but increased Δα and Δf. • R. pseudoacacia suppress the coarsening and deterioration of the surface. The soil particle size distribution (PSD) is a fundamental physical property that can affect soil nutrients, soil structure characterization and soil hydraulic properties. However, the effect of plant expansion on soil PSD is not clear. Therefore, in this study, fractal theory was applied to quantitatively describe the PSD. On Mount Tai, artificial afforestation with Robinia pseudoacacia is helpful in restoring ecosystems and improving soil quality. However, clonal spread allows R. pseudoacacia to easily escape cultivation, leading to the formation of mixed forests. Therefore, exploring the effect of R. pseudoacacia expansion on soil PSD is important. The results show that 1) R. pseudoacacia expansion increased the clay and silt contents and reduced the sand content; 2) R. pseudoacacia expansion significantly reduced the capacity dimension, entropy dimension, and correlation dimension and increased the width and asymmetry of the singularity spectra but was unrelated to the entropy dimension/capacity dimension; and 3) the capacity dimension was significantly positively correlated with the sand content and significantly negatively correlated with the silt and clay contents, but the asymmetry of the soil PSD was inconsistent with the capacity dimension. In summary, R. pseudoacacia can reduce the heterogeneity of the PSD by increasing the distribution range and density of the PSD. Our results provide important insight into the effect of plant expansion on soil PSD. [ABSTRACT FROM AUTHOR]

The structural, magnetic, and magnetocaloric properties of Ni 44 Mn 45-x Sn 11 Fe x (x = 0, 1, 2 and 3) Heusler alloys have been studied detailly by means of X-ray diffraction, differential scanning calorimetry, and magnetization measurements. The martensitic transition temperature (T M) and austenite Curie temperature (T A C) increase gradually with increasing Fe content. Large differences in magnetization between the ferromagnetic austenite and weakly magnetic martensite phases and obvious thermal hysteresis have also been observed during the martensite transformation. With the magnetic field change up to 0–7 T, the maximum value of magnetic entropy changes reaches 26.7 and 23 J kg−1K−1 for x = 1 and 2, respectively, which are much larger than the undoped sample (9.8 J kg−1K−1). Whereas, the effective refrigerant capacity RC eff reduced due to Fe doping increased the hysteresis loss. The alloy for x = 1 has highest RC value of 172 (255) J kg−1 for a magnetic field change of 0–5 T (0–7 T), furthermore, a large magnetic entropy change and moderate RC eff has been obtained around room temperature. • Fe-doped Ni44Mn45-xSn11Fex (x = 0, 1, 2 and 3) Heusler alloys were fabricated. • Structural and magnetic properties of Ni44Mn45-xSn11Fex were investigated. • Considerable magnetocaloric performances in Ni44Mn44Sn11Fe were realized. [ABSTRACT FROM AUTHOR]

Abstract: The greatest source of rock dust on rock roadway heading face is the roadheader. Overexposure to respirable rock dust can be a serious health hazard to roadheader operators and other workers. One of the rock roadways, named North Belt Main Entry (NBME), belonging to the underground coal mine Zhuxianzhuang, located in east China, is being driven by the EBZ318H roadheader. The cross-section of the roadway is 15.84m2, and the heading face has a high concentration of respirable rock dust. This paper presents a study of rock roadheader dust control by foam, taking into account the dust generation characteristics. A new foam preparation system and application method has been proposed and the dust suppression effect of foam has been assessed by dust concentration measurements taken at two points next to the roadheader operator in the previously mentioned underground coal mine. The results have shown that the foam dramatically reduced the rock dust concentrations. The roadheader operator’s respirable dust exposures were lowed from 540.2mg/m3 to 84.3mg/m3, and the dust suppression efficiency reached 84.4% on the NBME heading face. In addition, the visibility and environment of the heading face was significantly improved. It is concluded that the foam showed a significant improvement on the rock dust capture efficiency, and avoided the main deficiencies of conventional water sprays. [Copyright &y& Elsevier]

• Proposed a method to estimate dual-energy CT images from traditional single energy CT image together with a single view projection at a different energy level. • Deep-learning algorithm is used to perform material-decomposition-like operations. • The approach can provide superior material-specific images with significantly reduced noise compared with standard DECT imaging. [Display omitted] Dual-energy computed tomography (DECT) is of great significance for clinical practice due to its huge potential to provide material-specific information. However, DECT scanners are usually more expensive than standard single-energy CT (SECT) scanners and thus are less accessible to undeveloped regions. In this paper, we show that the energy-domain correlation and anatomical consistency between standard DECT images can be harnessed by a deep learning model to provide high-performance DECT imaging from fully-sampled low-energy data together with single-view high-energy data. We demonstrate the feasibility of the approach with two independent cohorts (the first cohort including contrast-enhanced DECT scans of 5753 image slices from 22 patients and the second cohort including spectral CT scans without contrast injection of 2463 image slices from other 22 patients) and show its superior performance on DECT applications. The deep-learning-based approach could be useful to further significantly reduce the radiation dose of current premium DECT scanners and has the potential to simplify the hardware of DECT imaging systems and to enable DECT imaging using standard SECT scanners. [ABSTRACT FROM AUTHOR]

• The optimum ball-milling time is 3–5 h to obtain amorphous alloy. • The theory of the energy barrier and schematic diagram of atomic arrangement were adopted to interpret the amorphization and crystallization mechanisms. • The uniform microstructure was obtained by annealed at 700 ℃ for 20 min. • The coercivity (H cj) and the remanence (B r) are increased by 1.28 kOe and 23.6 emu/g, respectively. The phase transformation mechanism and magnetic properties of the Sm-Fe alloy powders produced by melt-spinning and high-energy ball milling are investigated. The amorphous phase is stable between 2 and 5 h, and the SmFe 9 phase is precipitated from the amorphous matrix after milled for 5 h. The time of 3–5 h is optimal to obtain the largest number of short-range/medium-range order in the amorphous alloy, which can contribute to the formation of uniform microstructure in the subsequent crystallization annealing process. The magnetic properties of the nitrided powders produced by crystallizing the amorphous precursors are improved compared to the properties of those produced by direct melt-spinning. The coercivity (H cj) and the remanence (B r) are increased by 1.28 kOe and 23.6 emu/g, respectively. This kind of micro-regulation plays a key role in improving the magnetic properties after nitrogenating and lays the foundation for the production of bulk materials in the future. [ABSTRACT FROM AUTHOR]

Through analyzing the transient components and transient characteristics in transient zero-sequence current (TZSC), a novel fault feeder detection method based on the transient correlation of non-power frequency components (NPFCs) for the resonant grounded system is proposed. Firstly, using variational mode decomposition combined with fast Fourier transformation (VMD–FFT) to decompose the TZSC, by removing the power frequency components and noise signals, the transient NPFCs can be obtained. Secondly, to reflect the overall changing trend between faulty and healthy currents, the moving average filter is introduced to smooth the NPFCs; in this way, the fault transient features can be accurately revealed. Finally, the faulty feeder can be detected by comparing the threshold with the maximum difference value of comprehensive correlation coefficient of NPFCs. The detection results show that the proposed fault detection method can accurately select the faulty feeder; it is unaffected by fault resistances, fault phase angles, etc. Moreover, the detection method can resist noise interference. [ABSTRACT FROM AUTHOR]

• Weak shallow detachment in the Longmen Shan belt can lead the deformation into the foreland. • Duplex detachment has controls on the out-of-sequence style of the Longmen Shan belt. • The current structural pattern of the Longmen Shan belt is produced by upper crustal thrusting. The topic of the Longmen Shan fold-and-thrust belt has been vigorously debated due to the steep topography in contrast with the low convergence rate and earthquake hazards. The Longmen Shan fold-and-thrust belt is characterized by two main detachments: a strong lower detachment at 15–17 km depth in the hinterland and a weak upper detachment at ~7 km depth in the Sichuan Basin. Nevertheless, how the two detachments control deformation in the Longmen Shan remains unclear. In this study, we focus on the mechanical strengths of the two detachments in the study area and design three analog models to investigate the kinematics and mechanisms of the Longmen Shan fold-and-thrust belt. All three model experiments have the same strong lower detachments at the basement, but different upper detachments. The results indicate that for Model 1 with no upper detachment and Model 2 with a strong frictional upper detachment, the strain and deformation only concentrate near the mobile backwall, and particle image velocimetry analysis reveals that both models deform in the forward in-sequence style. However, for Model 3 with a weak ductile upper detachment, the strain and deformation propagate into the foreland, and the model deforms in the out-of-sequence style consistent with the Longmen Shan fold-and-thrust belt. The model results indicate that the spatial relation of strong lower detachment and weak upper detachment may be one of the important factors producing the current structural pattern and the out-of-sequence style of the Longmen Shan fold-and-thrust belt. [ABSTRACT FROM AUTHOR]

• The magnetism and magnetocaloric effect (MCE) were investigated in Er 4 CoCd compound. • A large magnetocaloric effect in Er 4 CoCd compound was observed. • The origin of MCE and its potential application in Er 4 CoCd were discussed. The Er-based compound Er 4 CoCd was synthesized successfully and its structural, magnetic together with magnetocaloric properties were investigated in detail. The Er 4 CoCd crystallized in a Gd 4 RhIn-type structure with the space group of F 4 ¯ 3 m , which was confirmed by Rietveld refinement. A ferromagnetic transition was observed around its Curie temperature (T C) of 12.5 K accompanied by a large magnetocaloric effect (MCE). The performance of MCE for Er 4 CoCd was evaluated by the isothermal maximal magnetic entropy (- Δ S M max) , the temperature averaged entropy change (TEC) at 10 K temperature lift [ TEC (10 K)], and the relative cooling power (RCP). The values of - Δ S M max , TEC (10 K), and RCP of Er 4 CoCd are 20.4 J/kg K, 19.2 J/kg K, and 503 J/kg under the magnetic field change (Δ H) of 0–5 T, respectively. [ABSTRACT FROM AUTHOR]