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• Operando observation system is developed to make in-situ test on lab-on-a-chip. • Actual evolution process of charged submicron particles is recorded intuitively. • This work demonstrates direct influence of drag force on particle chain fracture. • It is first-time visualization of mechanism elucidation of particle re-entrainment. Inhalable particle is a harmful air pollutant that causes a significant threat to people's health and ecological environments, which should be removed to purify air, but there exists limited removal efficiency due to particle re-entrainment. Here, Operando observation system based on microscopic visualization method is developed to make in situ test of particle migration, deposition and re-entrainment characteristics on a lab-on-a-chip to achieve the investigation in micro-level scale. The deposition evolution of charged particles is recorded in electric field region intuitively, which confirms the fracture of particle chain occurs during the growth process of deposited particles. It captures the instantaneous process that a larger particle with micron size due to the coagulation of submicron particles fractures from main body of the particle chain for the first time. The analysis of migration behavior of a single submicron particle near electrode surface demonstrates the direct influence of drag force on the fracture of particle chain. This work is the first-time visualization of dynamic process and mechanism elucidation of particle re-entrainment at the micron level, and the findings will provide the theory support for the particle re-entrainment mechanism and bring inspires of enhancing capture efficiency of inhalable particle. [Display omitted] [ABSTRACT FROM AUTHOR]

The high integration density of microelectronic devices leads to local heat accumulation, and effective heat dissipation and signal transmission of packaging materials have become the primary issues to be solved. However, existing polymer materials have difficulty meeting the requirements due to their unsatisfactory thermal conductivity and thermal expansion properties. In this work, we proposed the use of digital light processing (DLP) printing technology to construct a triply periodic minimum surface (TPMS) skeleton, and a continuous and efficient heat conduction path was successfully constructed in epoxy resin by impregnating h-BN on the skeleton surface. When the loading of h-BN was 20 vol%, the thermal conductivity of the TPMS(SiO 2)@BN/EP(BN) composites was 1.86 W/(m·K), which was 786 % higher than that of pure epoxy resin. In addition, the thermal expansion coefficient of the composites decreased by more than 70 %. At the test frequencies of 3∼10 MHz, the composites showed stable dielectric properties, and the dielectric constant was always maintained in a low range, between 3.85 and 4.15. This work has realized the transformation of the method for constructing a heat conduction path from disordered to ordered and from random to repeatable. This provides a new strategy for the selection of microelectronic packaging materials. [ABSTRACT FROM AUTHOR]

Reported here is a systematical investigation on the crystal structure, magnetic properties and magnetocaloric (MC) effect of three rare earth (RE) molybdate RE 2 MoO 6 (RE = Dy, Tb and Gd) oxides. The X-ray powder diffraction and the morphology as examined using the scanning electron microscope indicate phase-pure and polycrystalline nature of these oxides. The temperature (2–100 K) and magnetic field (up to 5 T) dependence of the magnetic measurements determine the magnetic phase transition (MPT) and MC properties. All the present RE 2 MoO 6 oxides crystallize in a monoclinic structure belonging to C 2/ c space group with the antiferromagnetic ordering at low temperature. Moreover, the RE 2 MoO 6 oxides hold reasonable values of MC parameters including the maximum isothermal magnetic entropy change/temperature-averaged entropy change (2 K lift) and relative cooling power values have been evaluated with the magnetic change of 0–5 T, yielding 17.22 (17.08) J/kgK and 277.67 J/kg for Dy 2 MoO 6 , 17.03 (16.83) J/kgK and 261.12 J/kg for Tb 2 MoO 6 , as well as 27.68 (26.69) J/kgK and 228.14 J/kg for Gd 2 MoO 6 , respectively. These acceptable MC parameters make the present RE 2 MoO 6 oxides potential candidates for cryogenic magnetic refrigeration (MR). [ABSTRACT FROM AUTHOR]

The magnetocaloric effect (MCE) has been extensively studied in various magnetic solids, aiming to both facilitate practical applications in magnetic cooling and deepen our understanding these materials' intrinsic properties. This study presents a systematic investigation of Gd 2 Ti 2 O 7 oxide, characterized by a geometrically frustrated magnetic structure, focusing on its structural and magnetic characteristics through experimental analysis and theoretical calculations. Emphasis is placed on its magnetic phase transition (MPT) and magnetocaloric properties, scrutinizing temperatures as low as 0.4 K and magnetic fields up to 16 T. The results reveal that Gd 2 Ti 2 O 7 oxide possesses a crystalline cubic pyrochlore-type structure with an antiferromagnetic (AFM) semiconductor ground state. The material undergoes a first-order MPT in low field and low-temperature regimes, transitioning to a second-order MPT above 2 K up to 16 T. Evaluation of magnetocaloric parameters, including maximum magnetic entropy change, temperature-averaged entropy change, relative cooling power, and refrigerant capacity, indicates moderate values under low magnetic field changes, while significantly large values are achievable under high magnetic field changes. This finding suggests that potential cryogenic magnetocaloric materials (MCMs) with optimal performance should exhibit low MPT temperatures induced by magnetic frustration and possess a ground state with a sufficiently large magnetic moment induced by low magnetic fields, thus avoiding excessively strong AFM coupling. This study lays the groundwork for future cryogenic MCM design and provides valuable insights into the intrinsic properties of geometrically frustrated magnetic materials. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, a detailed investigation with respect to the structural, cryogenic magnetic properties and magnetocaloric performances of RE 2 CuMnO 6 (RE = Gd, Dy, Ho and Er) double perovskite (DP) compounds has been performed. All the RE 2 CuMnO 6 compounds are confirmed to B -site disordered and crystallized in the GdFeO 3 -type structure (Pnma space group, N 62, oP20). The magnetic transition temperatures (T M) are found to be ~7.5 K for Gd 2 CuMnO 6 , ~12.1 K for Dy 2 CuMnO 6 , ~12.2 K for Ho 2 CuMnO 6 , and ~3.6 K for Er 2 CuMnO 6 , respectively. Moreover, for checking the magnetocaloric performances several vital parameters including -Δ S M max (peak value of magnetic entropy change, -Δ S M), TEC (3) (temperature averaged -Δ S M) and RCP (relative cooling powers) are evaluated to be 7.84, 7.73 J/kgK and 151.1 J/kg for Gd 2 CuMnO 6 , 5.69, 5.59 J/kgK and 180.9 J/kg for Dy 2 CuMnO 6 , 7.12, 7.05 J/kgK and 192.4 J/kg for Ho 2 CuMnO 6 , as well as 9.92, 9.60 J/kgK and 195.9 J/kg for Er 2 CuMnO 6 under the magnetic field change Δ H = 5 T, respectively. [ABSTRACT FROM AUTHOR]

In this study, we present the crystal structure, magnetic properties, and cryogenic magneto-caloric effect (MCE) of RE 2 FeAlO 6 (RE = Gd, Dy, Ho) oxides. The XRD refinement analysis suggests that all the RE 2 FeAlO 6 oxides are crystallized in B-site disordered orthorhombic structure. The RE 2 FeAlO 6 oxides exhibit large MCEs around T C. The peak magnetic entropy change (-Δ S M) and refrigeration capacity (RC) are 25.9 J/(kgK) and 240.1 J/kg for Gd 2 FeAlO 6 , 10.7 J/(kgK) and 274.9 J/kg for Dy 2 FeAlO 6 , 9.6 J/(kgK) and 249.6 J/kg for Ho 2 FeAlO 6 under Δ H of 0–70 kOe, respectively. Notably, Gd 2 FeAlO 6 exhibits promising magneto-caloric performance and therefore is a favorable candidate for cryogenic magnetic refrigeration. [ABSTRACT FROM AUTHOR]

The microstructure, cryogenic magnetic properties, magneto-caloric effect (MCE) and refrigeration performance of equi-atomic HoErGdCuNi ribbons have been investigated. Fully amorphousized structure with uniform distribution for all constituent elements is obtained. A table-like MCE that covers the temperature region from liquid nitrogen to liquid hydrogen is observed, which leads to a giant refrigerant capacity. Accordingly, the maximum magnetic entropy change (- Δ S M max) , temperature-averaged entropy change [ TEC (10)] and refrigerant capacity (RC) are 15.8 J/kgK, 15.7 J/kgK and 903 J/kg, respectively, at the magnetic field change (Δ H) of 0–7 T. The equi-atomic HoErGdCuNi amorphous ribbons with good MCE parameters especially those with large RC values, are an attractive candidate for cryogenic magnetic refrigeration materials. • Magnetism and magnetocaloric effect (MCE) of HoErGdCuNi ribbons were investigated. • A giant refrigerant capacity (RC) in HoErGdCuNi ribbons was obtained. • The origin of MCE and its potential application in HoErGdCuNi were discussed. [ABSTRACT FROM AUTHOR]

Abstract It is well known that rare earth (RE) based intermetallic compounds reveal various interesting magnetic properties depending on the crystallized structures and the constituent elements, paving the way for potential applications in different fields. Recent progresses regarding magnetic properties and magnetocaloric effect (MCE) in ternary rare earth RE 2 T 2 X (RE = Gd-Tm; T = Cu, Ni, Co; and X = Cd, In, Ga, Sn, Al) intermetallic compounds are reviewed in this paper. Some of them exhibit excellent MCE performances which make them attractive in the field of magnetic refrigeration at low temperature. With the aim of understanding the magnetocaloric characteristics of RE 2 T 2 X compounds, the crystal structure, magnetism and magnetic phase transition are also focused. The origin of the MCE together with the physics behind and the potential application of RE 2 T 2 X compounds are thoroughly considered. Highlights • Magnetic and magnetocaloric properties in RE 2 T2X compounds are reviewed. • The RE 2 T2X compounds show four types of crystallize structures. • Some of them exhibit excellent cryogenic magnetocaloric performances. • The origin of magnetocaloric effect in RE 2 T2X compounds is discussed. [ABSTRACT FROM AUTHOR]

Abstract Magnetic cooling technology based on the magneto-caloric effect (MCE) has emerged as a viable alternative to conventional vapor compression refrigeration technology. Exploring suitable magnetic solids with promising magneto-caloric performances is a key issue in this field. Here, we report a systematic characterization of the glass forming ability, microstructure, magnetism and MCE of Ho 57 Cu 25 Al 18 and Tm 57 Cu 25 Al 18 amorphous ribbons. Promising MCE performances were observed for both ribbons at low temperature. Compared with most of the rare earth-based amorphous alloys, both ribbons were found to have comparable or even larger values of -Δ S M max (maximum magnetic entropy change), RC (refrigeration capacity) and RCP (relative cooling power). These promising magneto-caloric performances make amorphousized RE 57 Cu 25 Al 18 ribbons attractive for active cryogenic magnetic refrigeration. Highlights • Magnetism and magnetocaloric effect (MCE) in RE 57 Cu 25 Al 18 ribbons were studied. • Promising MCE performance was observed in amorphous RE 57 Cu 25 Al 18 ribbons. • The origin of MCE in amorphous RE 57 Cu 25 Al 18 ribbons was discussed. [ABSTRACT FROM AUTHOR]

Abstract Double perovskite Pr 2 NiMnO 6 (PNMO) and Pr 2 CoMnO 6 (PCMO) ceramics have been synthesized and their crystal structure, microstructure, as well as cryogenic magnetic properties and magnetocaloric performance have been investigated. The crystal structure of PNMO and PCMO ceramics was determined to be monoclinic with space group of P21/n at room temperature. A ferromagnetic to paramagnetic (FM-PM) phase transition (second-order) occurred in PNMO and PCMO around 208 and 170 K, respectively. Significant reversible magnetocaloric effect (MCE) was found and the values of the maximum magnetic entropy change (-Δ S M max) were 3.15 and 3.91 J/kg-K under the magnetic field change (Δ H) of 0–7 T in PNMO and PCMO, respectively. The corresponding relative cooling power (RCP) values were 241.9 and 229.9 J/kg. [ABSTRACT FROM AUTHOR]

Pyrochlore RE 2 TiMnO 7 ( RE = Dy and Ho) compounds were synthesized using a ceramic method, and their crystal structures, microstructures, and cryogenic magnetic properties were determined. Dy 2 TiMnO 7 and Ho 2 TiMnO 7 compounds belong to the Fd-3m space group with a cubic pyrochlore structure and show a considerable reversible magnetocaloric effect (MCE) in the vicinity of the second-order ferromagnetic-paramagnetic (FM-PM) phase transition at the Curie temperature ( T C ) of 7.6 and 7.5 K, respectively. The obtained maximal values of magnetic entropy change (-Δ S M max ) for Dy 2 TiMnO 7 and Ho 2 TiMnO 7 are 12.50 and 13.95 J/kg K under a magnetic field change (Δ H ) of 0–7 T, respectively. Correspondingly, the relative cooling power ( RCP ) values reach 530.3 and 573.2 J/kg, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ferromagnetic Al-Mn-Fe-Co-Cr high-entropy (HE) alloys were fabricated. • Structural, magnetic and magnetocaloric (MC) properties were reported. • Combined experimentally determined and theoretically analyzed was performed. • Excellent MC properties were achieved at room temperature. • These HE alloys have potential for room temperature magnetic refrigeration. In the present study, the structure, magnetic phase transition, and magnetocaloric performance of Al 20 Mn 20 Fe 20 Co 14.5+ x Cr 25.5- x (x = 0, 1, and 2), a series of typical rare-earth-free high-entropy (HE) alloys, were experimentally determined and theoretically analyzed based on first-principle calculation. Ferromagnetic behavior was established and their Curie temperature could be tuned in a wide temperature range, which correlated with Co content; specifically, it increased from 282.8 K for Co 14.5 Cr 25.5 to 345.8 K for Co 16.5 Cr 23.5. In addition, the electronic density of states and magnetic moments associated with each consistent element were analyzed in the HE alloys. Maximum magnetic entropy changes of 1.135, 1.150, and 1.096 J/kgK were obtained for an x of 0, 1, and 2 under a magnetic field change of 5 T. These values are comparable or superior to those of reported 3 d metal-based HE alloys. Furthermore, the experimental characterizations and theoretical predications agreed well, which provided an in-depth understanding of the rare-earth-free HE Al-Mn-Co-Fe-Cr alloy system, which is expected to be expanded to other systems in the future. [ABSTRACT FROM AUTHOR]

The structure, magnetic transition and magnetocaloric properties in the ternary gallium intermetallic compounds of Ho 2 Ni 2 Ga and Tm 2 Ni 2 Ga have been systematically investigated by using X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and magnetization measurements. As found from powder XRD and Rietveld refinement, Ho 2 Ni 2 Ga and Tm 2 Ni 2 Ga crystallized in an orthorhombic structure of the W 2 B 2 Co type belonging to the Immm space group. Both compounds are ordering antiferromagnetically at low temperatures and under low magnetic fields together with a field-induced metamagnetic transition from antiferromagnetic (AFM) to ferromagnetic (FM). Peculiar and similar magnetocaloric properties are observed for both compounds, i. e., an inverse magnetocaloric effect (positive magnetic entropy change, Δ S M ) under low magnetic field changes (Δ H ) and at low temperatures together with a large normal reversible magnetocaloric effect under high Δ H . The positive Δ S M below/at the Néel temperatures ( T N ) is ascribed to first order transition from antiferromagnetic (AFM) to ferromagnetic (FM) states, whereas the negative Δ S M above T N is due to the fact of the magnetic transition from paramagnetic (PM) to ferromagnetic (FM) states. Based on the field-dependent magnetization data, the maximum magnetic entropy change (−Δ S M max ), relative cooling power ( RCP ) and refrigerant capacity ( RC ) are established, and the corresponding values are 9.6 J/kg K, 276 J/kg and 206 J/kg for Ho 2 Ni 2 Ga, and are 4.3 J/kg K, 60 J/kg and 46 J/kg for Tm 2 Ni 2 Ga, respectively, for a magnetic field change of 0–70 kOe. [ABSTRACT FROM AUTHOR]

The magnetic properties and magnetic entropy change of amorphousized Tm 60 Co 20 Ni 20 ribbon were systematically studied. The results indicate that the Tm 60 Co 20 Ni 20 amorphous ribbon reveals a second order magnetic transition (paramagnetic to ferromagnetic state) based on the Arrott plots and rescaled magnetic entropy change curves. A large magnetic entropy change is achieved around its Curie temperature of T C ∼6.7 K. Under the magnetic field change (Δ Η ) of 0–5 T, the maximum values of magnetic entropy change (−Δ S M max ) and relative cooling power ( RCP ) are 17.1 J/kg K and 273 J/kg, respectively. In particular, under a relative low Δ Η of 0–2 T, a large magnetic entropy change of 11.8 J/kg K reaches, making it attractive in the field of low-temperature magnetic refrigeration. [ABSTRACT FROM AUTHOR]

Here we report on a detailed investigation of the crystal structure, cryogenic magnetic and magneto-caloric properties in Ho 2 BaCuO 5 cuprate. The Ho 2 BaCuO 5 crystallized in the orthorhombic crystal structure with Pbnm space group and undergoes a paramagnetic (PM) to antiferromagnetic (AFM) transition at the Néel temperature ( T N ) of 12.5 K. An obvious signal change in the magneto-caloric effect (MCE) was observed, which is correlated with the fact of the AFM ground state inducing a small negative magnetic entropy change (-Δ S M ) at/below T N and a field-induced metamagnetic transition (first ordered) from AFM to ferromagnetic (FM) producing a large positive -Δ S M above T N . For a magnetic field change of 0–7 T, the -Δ S M max ≈ 10.4 J/kg K, RCP ≈ 263 J/kg and RC ≈ 199 J/kg for the maximum magnetic entropy change, relative cooling power and refrigerant capacity are evaluated, respectively. [ABSTRACT FROM AUTHOR]

Two single-phased aluminide RE NiAl 2 ( RE = Ho and Er) compounds have been synthesized by an arc-melting method. The magnetic properties and magnetocaloric effect (MCE) of HoNiAl 2 and ErNiAl 2 have been studied by magnetization measurements. A second-order paramagnetic (PM) to ferromagnetic (FM) phase transition together with a considerable reversible MCE were observed around the Curie temperature T C ∼7.5 K and 5.0 K for HoNiAl 2 and ErNiAl 2 , respectively. Under the magnetic field change (Δ H ) of 0–5 T, the maximal values of magnetic entropy change, refrigerant capacity and relative cooling power are 14.0 J/kg K, 171 J/kg, 213 J/kg for HoNiAl 2 and 21.2 J/kg K, 267 J/kg, 357 J/kg for ErNiAl 2 , respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hollow spherical-shell NiO was prepared by a ligand modulation MOFs-derived method. • Hollow NiO improved benzene conversion and CO 2 selectivity, reducing energy consumption significantly. • Abundant surface O species of NiO are activated by plasma and thus induce superior catalytic ability. • Synergistic effect was clarified as NiO enhancing plasma field while plasma inspiring NiO oxidation ability. While catalyst morphology plays an essential role in traditional thermal catalysis, the specific effects in plasma catalysis deserve further in-depth study. In the present study, hollow NiO nanospheres with a rambutan-like structure were successfully prepared by MOFs-derived method involving morphology modulation, and employed for the in-plasma catalytic oxidation of benzene. The results show an enhancement of 60 % for benzene removal, while CO 2 selectivity was increased by 20 %. The energy consumption for 95 % benzene removal efficiency (RE 95%) was also reduced from 3600 J/L to 1100 J/L. Specifically, the hollow spherical shell structure is more abundant in surface oxygen species, including chemisorbed oxygen and surface lattice oxygen, which can be activated by plasma; the hollow structure also modulates the plasma discharge by shielding effect. The plasma field in turn also excites the oxidation activity of NiO, thus achieving the synergistic effect. In addition, a more comprehensive benzene decomposition pathway is proposed by analysis of the gaseous and non-gaseous intermediates (tar), where the plasma non-selectively breaks the chemical bonds of reactants and the catalyst selectively oxidizes the organic intermediates to CO 2 , and they promote each other to achieve synergistic effects. [ABSTRACT FROM AUTHOR]

We reported the magnetism, magnetic phase transition behavior and magnetocaloric effect of the ternary Dy 2 CuSi 3 and Ho 2 CuSi 3 compounds. A second order magnetic phase transition from a paramagnetic (PM) to ferromagnetic (FM) state around their respective Curie temperatures were confirmed by using the magnetic measurements and rescaled magnetic entropy change curves in both compounds. A large magnetic entropy change was obtained with the absence of thermal and magnetic hysteresis loss in both compounds. The maximal magnetic entropy change (-Δ S M max ) reach 18.3 and 28.3 J/kg K for a magnetic field change of 0–70 kOe in Dy 2 CuSi 3 and Ho 2 CuSi 3 , respectively. The corresponding values of relative cooling power ( RCP ) are evaluated to be 460 J/kg and 627 J/kg, respectively. [ABSTRACT FROM AUTHOR]

The magnetic properties, magnetocaloric effect (MCE) and universal behaviour of ternary Cadmium compounds Gd 2 Cu 2 Cd and Er 2 Cu 2 Cd have been investigated systematically. A second order magnetic phase transition from a paramagnetic to ferromagnetic state is observed for Gd 2 Cu 2 Cd and Er 2 Cu 2 Cd at their own Curie temperatures of T C ∼120 and 36 K, respectively. A large reversible MCE occurs near its own T C for both compounds. The maximum values of magnetic entropy change (−Δ S M max ) are 10.1 and 19.1 J/kg K under a magnetic field change of 0–7 T with no obviously hysteresis loss for Gd 2 Cu 2 Cd and Er 2 Cu 2 Cd, respectively. The corresponding values of refrigerant capacity ( RC ) and relative cooling power ( RCP ) are evaluated to be 386 and 373 J/kg, and to be 525 and 489 J/kg, respectively. The rescaled magnetic entropy change curves collapse onto a single curve for various magnetic fields, further confirming the Gd 2 Cu 2 Cd and Er 2 Cu 2 Cd compounds with the second order phase transition. [ABSTRACT FROM AUTHOR]

Dual-energy cone-beam computed tomography (DE-CBCT) is a promising imaging technique with foreseeable clinical applications. DE-CBCT images acquired with two different spectra can provide material-specific information. Meanwhile, the anatomical consistency and energy-domain correlation result in significant information redundancy, which could be exploited to improve image quality. In this context, this paper develops the Transformer-Integrated Multi-Encoder Network (TIME-Net) for DE-CBCT to remove the limited-angle artifacts. TIME-Net comprises three encoders (image encoder, prior encoder, and transformer encoder), two decoders (low- and high-energy decoders), and one feature fusion module. Three encoders extract various features for image restoration. The feature fusion module compresses these features into more compact shared features and feeds them to the decoders. Two decoders perform differential learning for DE-CBCT images. By design, TIME-Net could obtain high-quality DE-CBCT images using two complementary quarter-scans, holding great potential to reduce radiation dose and shorten the acquisition time. Qualitative and quantitative analyses based on simulated data and real rat data have demonstrated the promising performance of TIME-Net in artifact removal, subtle structure restoration, and reconstruction accuracy preservation. Two clinical applications, virtual non-contrast (VNC) imaging and iodine quantification, have proved the potential utility of the DE-CBCT images provided by TIME-Net. • First attempt to apply transformer to DE-CBCT. • Exploiting various information via multiple encoders to improve performance. • Obtaining high-quality DE-CBCT images from two complementary quarter-scans is feasible. • Reducing radiation dose and shortening acquisition time for DE-CBCT. [ABSTRACT FROM AUTHOR]

For the low concentration and intractable VOCs and CO 2 , plasma-coupled catalysis has superior advantages and development potential to deal with them. However, there are critical issues such as efficiency to be further improved and unclear coupling mechanism to reveal. In this review, various types of catalysts are categorized and evaluated by exploring their enhancement effect in plasma-catalytic system to indicate their synergistic excellence and application limitation. Besides, the detailed research of synergistic mechanism between plasma and catalysis is given more attention, which is rapidly progressing due to the development of in-situ experimental techniques and kinetic analysis approach. In our view, the future direction of plasma catalysis is to reveal the synergistic mechanism more deeply for efficiency improvement with efficient catalysts, and pave the way for practical application. [Display omitted] • The theoretical basis of plasma-coupled catalytic conversion of VOCs and CO 2 was introduced. • Enhancement of conversion efficiency by classified catalysts was discussed and evaluated. • Recent advances in in-situ experiments to investigate the synergistic mechanism were reviewed. • Prospects and challenges of plasma-coupled catalysis in VOCs removal and CO 2 conversion were pointed out. [ABSTRACT FROM AUTHOR]

The Heusler type Ni–Mn- Z (Z = Ga, ln, Sn, or Sb) alloys with magneto-structural transformations (MSTs) have received widespread research interests due to the exhibition of multifunctional characters. To further understand MSTs and improve the magnetocaloric performance of these alloys, in this work, the Ti doped Ni 48 Cu 2 Mn 36 Sn 14-x Ti x (x = 0, 1, 2, 3) ribbons have been fabricated and systematically determined with regard to the structural, magnetic, and magnetocaloric properties by means of X-ray diffraction (XRD), scanning electron microscope (SEM), differential scanning calorimetry (DSC), and magnetization measurements. All the ribbons are found to crystallize in the ordered cubic L2 1 austenite phases at room temperature and with the equiaxed austenite morphology. With the increasing Ti content, the average grain size and the MST temperature increase but the austenite Curie temperature (T A C) decrease gradually. Moreover, the thermal hysteresis and magnetic hysteresis loss are greatly reduced with the Ti doping. The value of average hysteresis loss (AHL) is reduced from 86 Jkg−1 for Ti0 to 25.5 Jkg−1 for Ti3 ribbon under 7 T. Additionally, enhanced magnetocaloric effect has been observed by Ti-doping. With the magnetic field change (ΔH) of 0–7 T, the largest value of magnetic entropy change reaches 15.4 Jkg−1K−1 (Ti2) among the Ni 48 Cu 2 Mn 36 Sn 14-x Ti x ribbons. The present work indicates that reasonable Ti doping could be a useful way to regulation the MSTs and improve the magnetocaloric performance of the Heusler type Ni–Mn–Sn-based alloys. • The Hesuler type Ni 48 Cu 2 Mn 36 Sn 14-x Ti x (x = 0, 1, 2, 3) ribbons are fabricated. • The structural, magnetic and magnetocaloric properties were investigated. • Ti doping could be a useful way to regulation the MSTs. • Enhanced magnetocaloric performances has been observed by Ti-doping. [ABSTRACT FROM AUTHOR]

The magnetic properties and magnetocaloric effect (MCE) in Dy 2 Cu 2 In compound have been investigated. Dy 2 Cu 2 In undergoes two magnetic phase transitions, a paramagnetic to ferromagnetic (FM) at T C ∼ 49.5 K followed by a spin reorientation (SR) at T SR ∼ 19.5 K. For a magnetic field change of 0–7 T, the maximum values of the magnetic entropy change (−Δ S M max ) are estimated to be 16.5 around T C and 6.7 J/kg K around T SR with a large relative cooling power ( RCP ) value of 617 J/kg. The modified Arrott plots and universal curves of the rescaled Δ S M confirmed that the magnetic phase transitions in Dy 2 Cu 2 In compound belongs the second order phase transitions. The present results may provide some clues to search for new magnetocaloric materials belonging to RE 2 T 2 X system. [ABSTRACT FROM AUTHOR]

The magnetic and magnetocaloric properties in the equiatomic intermetallic compounds of TmZnAl and TmAgAl have been investigated. The compounds undergo a second order magnetic transition from paramagnetic to ferromagnetic state around its own Curie temperatures T C ∼2.8 K and 3.3 K for TmZnAl and TmAgAl, respectively. A considerable reversible magnetocaloric effect (MCE) was observed at low temperature. For a magnetic field change of 7 T, the maximum values of magnetic entropy change (−Δ S M max ) and relative cooling power ( RCP ) are 11.8 J/kg K and 289 J/kg for TmZnAl, respectively, and the corresponding values for TmAgAl are 14.1 J/kg K and 315 J/kg. [ABSTRACT FROM AUTHOR]

Magnetic properties and magnetocaloric effect (MCE) in ErFeAl and HoFeAl intermetallic compounds have been studied systematically. Both compounds undergo a second order magnetic phase transition from paramagnetic to ferromagnetic state together with a probable spin reorientation transition at low temperature. A considerable reversible magnetocaloric effect was observed around its own Curie temperatures T C ∼55 K and 80 K for ErFeAl and HoFeAl, respectively. For a magnetic field change of 0–7 T, the maximum values of magnetic entropy change (−Δ S M max ) are found to be 8.3 and 9.9 J/kg K for RE = Er and Ho, respectively. The corresponding values of refrigerant capacity ( RC ) are evaluated to be 384 and 647 J/kg. [ABSTRACT FROM AUTHOR]

The magnetocaloric effect (MCE) of quaternary intermetallic compound ErNiBC has been investigated by magnetization and heat capacity measurements. The compound undergoes a paramagnetic (PM) to ferromagnetic (FM) transition at T C ~5 K and the ground state of Er ion forms a Kramer's doublet state. The magnetic transition is found to be second order in nature. The maximum magnetic entropy change (−Δ S M max ) and adiabatic temperature change (Δ T ad max ) of ErNiBC are 24.8 J/kg K and 8.6 K, respectively, for a magnetic field change of 0–50 kOe, and the corresponding refrigerant capacity ( RC ) is 312 J/kg. [ABSTRACT FROM AUTHOR]

Magnetism and magnetocaloric effect in RE AgAl ( RE = Er and Ho) intermetallic compounds have been studied. Both compounds undergo a second order magnetic phase transition from paramagnetic to ferromagnetic state. A large reversible magnetocaloric effect was observed around its own Curie temperatures T C ∼ 14 and 18 K for ErAgAl and HoAgAl, respectively. For a field change of 0–7 T, the maximum magnetic entropy change reaches 13.7 and 13.8 J/kg K for RE = Er and Ho, respectively. The corresponding relative cooling powers are evaluated to be 398 and 525 J/kg. [ABSTRACT FROM AUTHOR]

Highlights: [•] Magnetism and magnetocaloric effect in ErNi2−x Fe x B2C were studied. [•] Ni site Fe substitution can reduce the magnetic hysteresis of ErNi2B2C. [•] The origin of MCE and its potential application in ErNi2−x Fe x B2C were discussed. [ABSTRACT FROM AUTHOR]

The magnetic refrigeration (MR) technology by utilizing the magnetocaloric (MC) effects of magnetic solids have been realized to be a promising energy efficiency and environmentally friendly technology. Developing or discovering proper magnetic solids with promising MC performances is one of the most important tasks at present stage since a huge gap still exists between the requirement of practical MR application and the MC performances of the magnetic solids. Herein, we reported a combined theoretical and experimental investigation of the crystal structure together with the magnetic properties, magnetic phase transition (MPT) and MC performances in Gd 2 MgTiO 6 oxide. The Gd 2 MgTiO 6 is confirmed to crystalize in a B -site ordered monoclinic double perovskite (DP) crystal structure. A rather unstable antiferromagnetic (AFM) interaction with large magnetic moment and semi-conductor characteristic with the band gap of 2.977 eV have been confirmed in Gd 2 TiMgO 6 DP oxide at ground state. Giant reversible cryogenic MC effect together with excellent MC performances have been confirmed by a series of the figure of merits including the values of maximum magnetic entropy change (-Δ S M) and refrigerant capacity (RC), which are evaluated to be 46.21 J/kgK and 300.27 J/kg around 3.3 K with the magnetic change of 0–7 T, these values are much better than most of the recently reported famous cryogenic MC materials and the commercialized magnetic refrigerants gadolinium gallium garnet (GGG) as well. The observed excellent MC performances suggest that Gd 2 TiMgO 6 DP oxide is a promising candidate material for cryogenic MR applications. Graphical abstract [Display omitted]. [ABSTRACT FROM AUTHOR]

The rare-earths (RE) based amorphous materials with large magnetocaloric (MC) effects and excellent glass forming ability (GFA) have been recognized as promising candidates for magnetic refrigeration (MR). In this work, the RE 60 Co 20 Al 20 (RE = Ho, Er, Tm) amorphous ribbons were successfully fabricated and systematically determined with respect to the GFA, magnetic properties and MC effects. A second order magnetic phase transition (MPT) from ferromagnetic to paramagnetic (FM to PM) without noticeable field or thermal hysteresis has been observed around the Curie temperatures, T C ~ 22.3 K for Ho 60 Co 20 Al 20 , ~ 10.3 K for Er 60 Co 20 Al 20 , and ~ 5.0 K for Tm 60 Co 20 Al 20 , respectively. The MC parameters including the maximum magnetic entropy change (| Δ S M max |), temperature-averaged entropy change with 3 K lift [ TEC (3 K)], and relative cooling powder/refrigerant capacity (RCP/RC) have been determined to check the MC performances, and the corresponding values are determined to be 14.16, 15.57 and 15.06 J/kgK, to be14.04, 15.38 and 14.78 J/kgK, and to be 625.0/478.7, 505.7/391.8 and 334.0/243.4 J/kg for Ho 60 Co 20 Al 20 , Er 60 Co 20 Al 20 and Tm 60 Co 20 Al 20 under the field change Δμ 0 H = 5 T, respectively. The present results indicate that RE 60 Co 20 Al 20 (RE = Ho, Er, Tm) amorphous ribbons are considerable for cryogenic MR application. • The RE 60 Co 20 Al 20 (RE = Ho, Er, Tm) amorphous ribbons are fabricated. • The glass forming ability in RE 60 Co 20 Al 20 amorphous ribbons was investigated. • Large magnetocaloric effect in RE 60 Co 20 Al 20 has been observed. • RE 60 Co 20 Al 20 ribbons are considerable for cryogenic magnetic refrigeration. [ABSTRACT FROM AUTHOR]

The size distribution and composition of Co-rich particles in phase-separated Cu75Co25 alloys under magnetic fields of up to 4T were investigated. The results indicate that forced convective flow is suppressed effectively under a suitable magnetic field, whereas the thermoelectric magnetic convection under a high magnetic field cannot be neglected. The diffusive growth of Co-rich particle has a strong relation with the undercooling and a weak dependence on the magnetic field. The magnetic field does not alter the asynchronous crystallization behavior of Co-rich particles. [ABSTRACT FROM AUTHOR]

Highlights: [•] We developed a new method of pulsed laser gas phase evaporation–liquid phase collection nano-particles. [•] Fe2O3–TiO2 nano-composite particles were synthesized by this new laser method. [•] The prepared nano-composite particles are 20–50nm in diameter with high dispersion. [•] The magnetic properties of the nano-composite particles are dramatically improved. [Copyright &y& Elsevier]

[Display omitted] • Completely cross-linked film is obtained on the basis of photoinitiator markedly lowering the cross-linking temperature. • Hole mobility is enhanced by adding photoinitiator. • Energy levels become more suitable through doping photoinitiator. • Cross-linked hole transport layer improves power conversion efficiency of perovskite solar cells. To the best of our knowledge, poor environment stability is the main challenge for perovskite solar cells (PSCs). In this study, cross-linked hole transport layer (HTL) is built on perovskite crystal to guarantee the operation stability of mesoporous PSCs for the first time. Here, N,N' -di-p-tolyl- N,-N' -bis(4-vinylphenyl)-[1,1′-biphenyl]-4,4′-diamine (V-p-TPD) was applied as a hole-transportable polymerizable monomer with the assistance of ultraviolet photoinitiator 4-octyloxydiphenyliodonium hexafluoroantimonate (OPPI). Cross-linking process is conducted at a distinctly low temperature of only 100 °C by adjusting the V-p-TPD: OPPI ratio to 10:1, which is tolerable for the active black phase of perovskite. The resultant cross-linked V-p-TPD film is qualified with a high cross-linking degree of 99%, a high hole mobility of 3.84 × 10−4 cm2V−1s−1 and a hydrophobic surface with wetting angle of 94.6°. Mesoporous PSCs based on the obtained cross-linked HTL achieved a tremendous Power conversion efficiency (PCE) of 18.49%, which represents the state-of-the-art records of mesoporous PSCs with cross-linkable HTL. PCE of the unpackaged device can remain 88% of the initial value after 30 d in an atmospheric environment with a relative humidity of 60 ± 5%, and maintain 86% of the initial PCE after 200 h in 65 ± 2 °C argon atmosphere. This work presents a low-temperature processing strategy for the preparation of cross-linked HTL layer, which does favor to the stable and efficient energy harvesting application. [ABSTRACT FROM AUTHOR]

Abstract: Six segments of quadratic Bézier curve are joined together according to some geometrical rules to approximate fold shape. In a classification of folds based on this method, an ideal fold shape is determined by two parameters. The first one, uc , termed the axial lift-up ratio of the central part, generates the folds within a broad spectrum of forms ranging from box folds to chevron folds. The other one, γ, is the interlimb angle. In the quantitative description of complete folds with multiple layers, three new parameters, θ, T and E are used to describe the deflection angle of the axial plane, the thickness increment of hinge zone and the limb elongation, respectively. Based on the modeling method, the program “Bézier Fold Profiler” has been developed, with which most types of folds can be simulated by varying thirteen parameters. Two description methods, complete fold description and individual layer description, can be used for the quantitative analysis of folds. The description methods are carried out by the visual matching of the fold profile displayed on-screen from an imported digital image. The layer curves of the model are displayed on the fold image. This method has the advantage of speed and simplicity. [Copyright &y& Elsevier]

Abstract: In our geometric modeling, the inner layer of competent rock units in a detachment fold is approximated by several quadratic Bézier curves, which are joined together according to some geometrical rules, whereas the outer layers are calculated from the inner layer by parallel folding mechanism. In this model, an ideal fold is determined by three parameters: w, half of the distance between the locations of the fold''s two limbs where their dips are measured, θ 1 and θ 2, the dip angles of its two limbs. Two more parameters, respectively the axial lift-up ratio (u) and the limb elongation (E) may be used to change the ideal fold shape, if necessary. In kinematic modeling, downward deflection in the two synclines flanking an anticline is assumed to maintain constant area during folding. Both mathematical derivation and numerical simulation show that the reduction of the balanced area (A r) is directly proportional to the downward deflection angle (φ), and there is an approximate linear relationship between the detachment depth and the downward deflection angle. Based on this relationship, an iterative method is used to find the approximate value of φ. Furthermore, syn-folding growth strata can be modeled through calculating the velocity field above a detachment fold during folding. The method is applied to three seismic interpretation cross-sections of detachment folds respectively in Tarim Basin (western China), Zagros fold-belt (Iran) and Niger delta (western Africa). Variations of φ with the development of the detachment folds indicate the transfer of rock materials between the synclinal and anticlinal areas of the folds. [Copyright &y& Elsevier]

We herein provided a systematical determination of the structural and magnetic properties, especially of the magnetocaloric effect (MCE) and magnetocaloric performances of four rare-earth oxychlorides, i. e., the RE OCl (RE = Ho, Dy, Tb and Gd) compounds. The studied RE OCl compounds are all crystallized in the tetragonal matlockite structure (P 4/ nmm space group) and the RE , O, and Cl elements are with the RE 3+, O2−, and Cl− valence states, respectively. The DyOCl, TbOCl and GdOCl compounds reveal an antiferromagnetic transition at around approximate 9.5, 3.7 and 4.8 K, respectively. The magnetocaloric performances are checked by the maximum magnetic entropy change, relative cooling power, and temperature-averaged entropy change with 5 K lift, which are found to be 14.16 J/kgK, 375.55 J/kg and 13.89 J/kgK for HoOCl, to be 14.88 J/kgK, 488.14 J/kg, and 14.60 J/kgK for DyOCl, to be 14.59 J/kgK, 419.67 J/kg, and 14.42 J/kgK for TbOCl, and to be 16.16 J/kgK, 213.68 J/kg, and 14.39 J/kgK for GdOCl, with the magnetic field change of 0–7 T, respectively. [ABSTRACT FROM AUTHOR]

Highlights: [•] Effect of Fe/Ni addition on phase separated behavior in Cu75Co25 was investigated. [•] Particle size distribution in Cu75Co25 − x M x (M=Fe, Ni and x =1, 5) alloys was reported. [•] Small amounts Fe/Ni addition has similar effect to that of alter undercooling in Cu–Co alloy. [ABSTRACT FROM AUTHOR]

Hydrogels that possess adequate toughness in bulk and at soft interface are highly desirable. We report a fully physically crosslinked dual Amylopectin (Amy, the first network)/poly(N-hydroxyethyl acrylamide) (PHEAA, the second network) hydrogel, where both networks were hydrogen bonding (H-bonding) crosslinked, with super toughness in bulk and tunable adhesion at hydrogel-soft tissue interface. Through adjustment of hydrogen bond density, strong and tough hydrogels were prepared that exhibited different levels of adhesion strength and three adhesive failure mechanisms. We replaced Amy with oxidized starch (OSA) to synthesize dual and hybrid chemically/physically crosslinked OSA/PHEAA double network (DN) hydrogels that were capable of forming Schiff's bases at hydrogel-hydrogel or hydrogel-tissue interfaces, aside from interfacial H-bonding, incurring sustained, high interfacial toughness (1850 J m−2 hydrogel-hydrogel and 610 J m−2 hydrogel-tissue) in wet environments. Such tough and adhesive DN hydrogels have great potential in various applications such as engineering of artificial soft tissues or implantable devices that are intended to adhere to internal organs or tissues. • Fully physically crosslinked hydrogels via H-bonding. • Tunable adhesion and three adhesive failure mechanisms of hydrogels. • The sacrificial bonds including H-bonds and reversible Schiff's bases at the interface. • High interfacial toughness at hydrogel-hydrogel or hydrogel-tissue interfaces in wet environments. [ABSTRACT FROM AUTHOR]

The ternary rare earth RE CoSi 2 (RE = Er and Tm) intermetallic compounds were synthesized by means of arc-melting technique and their crystal structure, magnetism and magneto-caloric effect (MCE) were studied systematically. Both ErCoSi 2 and TmCoSi 2 crystallize in a CeNiSi 2 -type structure (Cmcm space group) confirmed by FULLPROF Rietveld refinement. Magnetization data indicates the antiferromagnetic (AFM) ground state for both RE CoSi 2 compounds, and a magnetic field-induced ferromagnetic (FM) transition occurs below the Neel temperature T N ∼6.9 K for ErCoSi 2 and ∼5.4 K for TmCoSi 2. Considerable reversible MCE in ErCoSi 2 and TmCoSi 2 was observed. The MCE performances of RE CoSi 2 are evaluated by -Δ S M max (maximal magnetic entropy change), TEC (3) (temperature averaged entropy change), and RCP (relative cooling power) with the values of 7.1 J/kg K, 6.8 J/kg K and 165.9 J/kg for ErCoSi 2 , as well as 8.7 J/kg K, 8.5 J/kg K and 152.9 J/kg for TmCoSi 2 , respectively, under Δ H (field change) of 0–50 kOe. Image 1 • CeNiSi 2 -type RE CoSi 2 (RE = Er and Tm) compounds were fabricated. • AFM ordering at T N ∼6.9 K for ErCoSi 2 and ∼5.4 K for TmCoSi 2. • A field-induced AFM to FM transition for both compounds occur below T N. • Considerable values of -Δ S M max, TEC , RC and RCP were found. • RE CoSi 2 compounds are also considerable for cryogenic magnetic cooling. [ABSTRACT FROM AUTHOR]

We herein fabricated two gadolinium-transition metal-based high entropy (HE) oxides of Gd(Mn 0.25 Fe 0.25 Al 0.25 Cr 0.25)O 3 [denoted as Gd(4 TM 0.25)O 3 ] and Gd(Mn 0.2 Fe 0.2 Al 0.2 Co 0.2 Ni 0.2)O 3 [denoted as Gd(5 TM 0.2)O 3 ] and determined their structural, magnetic, and magnetocaloric properties. Both of present HE oxides are found to crystallize in the single-phase perovskite-type orthorhombic structure with a homogeneous microstructure and exhibit prominent cryogenic magnetocaloric performances. The values of magnetic entropy change, refrigerant capacity, and temperature-averaged entropy change (6K-lift) under the magnetic field change of 0–7 T are estimated to be 20.34 J/kgK, 295.4 J/kg, and 19.56 J/kgK for Gd(4 TM 0.25)O 3 , and to be 22.45 J/kgK, 258.2 J/kg, and 20.79 J/kgK for Gd(5 TM 0.2)O 3 , respectively, which are comparable with recently reported candidate materials for practical magnetic cooling. These findings not only indicate potential applications of present perovskite-type Gd(4 TM 0.25)O 3 and Gd(5 TM 0.2)O 3 HE oxides, but also provide meaningful clues for exploring HE oxides with prominent cryogenic magnetocaloric performances. [ABSTRACT FROM AUTHOR]

The crystal structure together with the magnetic and magnetocaloric properties in RE 2 Ni 1.5 Ga 2.5 (RE = Dy, Ho, Er and Tm) have been investigated systematically. All the RE 2 Ni 1.5 Ga 2.5 compounds crystallize in a CaIn 2 -type structure of (P63/mmc space group). A second-ordered magnetic phase transition (SOPT) from ferromagnetic to paramagnetic (FM to PM) is occurred in RE 2 Ni 1.5 Ga 2.5 compounds with the Curie temperatures (T C) of approximately 16.1, 10.6, 4.1 and below 2 K for RE of Dy, Ho, Er and Tm, respectively. The magnetocaloric parameters including magnetic isothermal entropy change/temperature-averaged magnetic entropy change -Δ S M max/ TEC (5) and relative cooling power RCP are calculated with the values of 10.01/9.92 J/kg K and 418.6 J/kg for Dy 2 Ni 1.5 Ga 2.5 , 20.12/19.65 J/kg K and 644.1 J/kg for Ho 2 Ni 1.5 Ga 2.5 , 18.07/17.69 J/kg K and 447.1 J/kg for Er 2 Ni 1.5 Ga 2.5 , as well as 18.22/16.75 J/kg K and 330.7 J/kg for Tm 2 Ni 1.5 Ga 2.5 with magnetic field change (Δ H) of 0–7 T, respectively. Notably, Ho 2 Ni 1.5 Ga 2.5 exhibits ralatively high magnetocaloric parameters, which suggests that Ho 2 Ni 1.5 Ga 2.5 is a competitive candidate among the MCE materials in the field of cryogenic magnetic refrigeration (MR). • Magnetic properties and MCE in RE 2 Ni 1.5 Ga 2.5 compounds were studied. • Large values of -ΔS M max, TEC and RCP were observed at low temperature. • Ho 2 Ni 1.5 Ga 2.5 compound is competitive for cryogenic magnetic cooling. [ABSTRACT FROM AUTHOR]

• CO 3 2− enhanced catalytic activity and stability of Co 3 O 4 for PMS activation. • Faster catalysis occurred when solution pH exceeded but approached pH PZC of Co 3 O 4. • The dominated reactive species switched from •OH/SO 4 •− to 1O 2 after adding CO 3 2-. • CO 3 2− drove the catalytically active center migrating from Co(II) to Co(III). • Co(III) and CO 3 2−/OH- were electron and proton acceptors to promote 1O 2 evolution. Transition-metal catalysts (TMCs) for peroxymonosulfate (PMS) activation suffer from low stability (i.e. severe metal leakage and poor reusability) when maintaining high activity in water decontamination. An innovative carbonate (CO 3 2−)-mediated method to synchronously enhance the catalytic activity and stability of TMCs was developed herein. In a model PMS/Co 3 O 4 nanowire system for bisphenol A (BPA) degradation, the first-order kinetic constant and total organic carbon removal ratio were increased by 202.27% and 71.32% upon adding CO 3 2−, respectively. Meanwhile, the cobalt release amount was significantly reduced from 4.90 to 0.03 mg/L, and the number of reuse with high efficiency (>90% of BPA removal within 10 min) was augmented from 1 to 3 times. The CO 3 2− buffered pH decline to repress metal leakage, and promoted Co(III) reduction into Co(II) to avoid the over-oxidation of catalyst. Under the driving of CO 3 2−, the dominated reactive species were switched from •OH/SO 4 •- to 1O 2 accompanying the migration of catalytic center from Co(II) to Co(III). The Co(III) and CO 3 2−/OH- acted as electron and proton acceptors, respectively, to accelerate PMS decomposition into SO 5 •- and subsequent generation of vast 1O 2. This work proposes a green way to construct novel 1O 2 -based catalytic systems with excellent activity and stability for pollution remediation. [ABSTRACT FROM AUTHOR]

We present a detailed investigation of the crystal structure, magnetism and magneto-caloric performances of RE Co 2 B 2 C (RE = Gd, Tb and Dy) compounds. All compounds are described with a LuNi 2 B 2 C-type crystallographic structure (I 4/ mmm space group). A second-ordered paramagnetic to ferromagnetic (PM-FM) transition is observed in RE Co 2 B 2 C compounds around their Curie temperatures (T C) of 17.2, 5.3 and 7.7 K, and induced a considerable magneto-caloric effect (MCE) for GdCo 2 B 2 C, TbCo 2 B 2 C and DyCo 2 B 2 C, respectively. The magneto-caloric performances for RE Co 2 B 2 C were characterized by the isothermal magnetic entropy (- Δ S M max) , temperature averaged entropy change (TEC) with three different temperature lifts (3, 5 and 10 K), and relative cooling power (RCP). The corresponding values of - Δ S M max , TEC (3 K) and RCP under the magnetic field change (Δ H) of 0–5 T, are 10.34 J/kg-K, 10.23 J/kg-K, and 238.1 J/kg for GdCo 2 B 2 C, 18.09 J/kg-K, 17.83 J/kg-K, and 438.2 J/kg for TbCo 2 B 2 C, as well as 17.79 J/kg-K, 17.72 J/kg-K, and 480.1 J/kg for DyCo 2 B 2 C, respectively. • Magnetic properties and MCE in RE Co 2 B 2 C compounds were studied. • Large values of -ΔS M max, TEC, RC and RCP were observed at low temperature. • RE Co 2 B 2 C compounds are competitive for cryogenic magnetic cooling. [ABSTRACT FROM AUTHOR]

We herein investigated four rare earth (RE)-based oxides, the RE 2 SiO 5 (RE = Gd, Dy, Ho, and Er) silicates, regarding their structural and cryogenic magnetic properties. All the RE 2 SiO 5 silicates are found to crystallized in a monoclinic structure. X-ray photoemission spectroscopy spectra illustrate that RE , Si and O elements in RE 2 SiO 5 silicates are present as RE 3+, Si4+, and O2−, respectively. The Dy 2 SiO 5 reveals a first-order magnetic transition around 4.5 K. The magnetic phase transition temperatures are probably below 2 K for the RE 2 SiO 5 (RE = Gd, Ho, and Er) silicates. Large cryogenic magnetocaloric effects (MCE) and good magnetocaloric performances were observed in the RE 2 SiO 5 silicates. The MCE parameters in terms of the maximum magnetic entropy changes, the temperature-averaged entropy change (5 K-lift) and refrigerant capacity under a magnetic field change of 0–5 T are determined to be 35.5, 30.4 J/kgK, and 215.7 J/kg for Gd 2 SiO 5 , to be 13.3, 12.9 J/kgK, and 190.5 J/kg for Dy 2 SiO 5 , to be 15.3, 15.1 J/kgK, and 274.1 J/kg for Ho 2 SiO 5 and to be 17.9, 16.5 J/kgK, and 181.14 J/kg for Er 2 SiO 5 , respectively. These derived values of MCE parameters of the RE 2 SiO 5 silicates, especially for Gd 2 SiO 5 , are at similarly high level with or better than those of the updated candidate materials, making them also of potential for practical magnetic refrigeration applications. [ABSTRACT FROM AUTHOR]

Digital light processing 3D printing can be applied to fabricate complex silicon nitride (Si 3 N 4) components. However, because of the surface hydroxyl groups and large refractive index, it is still a foremost challenge to realize a stable photosensitive Si 3 N 4 slurry with combined benefits of low viscosity and large curing depth. In this study, we propose a new formulation strategy to prepare Si 3 N 4 slurry. Starting from the optimization of monomer ratio, we have systematically optimized powder particle size, dispersant and photoinitiator on the rheological properties and curing properties of Si 3 N 4 slurry. Specifically, we have fabricated a stable photosensitive Si 3 N 4 slurry (48 vol%) with a viscosity of 2.09 Pa s (30 s−1), a critical curing energy of 126.09 mJ/cm2 and a maximum curing depth of 80 µm. Finally, based on this optimized slurry, we have successfully obtained complex Si 3 N 4 green body with no defect, which demonstrates great potential to fabricate arbitrary complex ceramic components for various applications. [ABSTRACT FROM AUTHOR]

The synergistic effect of lanthanum oxide (La 2 O 3 ) on the flame retardant properties and mechanism of a novel intumescent flame retardant polylactide composites (PLA/IFR) was investigated by the means of limited oxygen index (LOI), catalytic effectivity analysis (CAT-EFF), vertical burning test (UL-94), microscale combustion calorimetry (MCC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), Laser Raman spectroscopy (LRS) and X-ray photoelectron spectroscopy (XPS). La 2 O 3 enhanced the LOI value of the PLA/IFR composite dramatically and all the composites passed the UL-94 V-0 rating test. PLA/IFR/1% La 2 O 3 had the highest CAT-EFF, and the LOI value of the composite increased from 32.8 to 42.2% according to catalytic affectivity (CAT-EFF) analysis. 1%La 2 O 3 enhanced the fire retardant performance of PLA/IFR, resulting consequently in reduction of heat release rate (HRR), total heat release (THR), heat release capacity (HRC) and degree of flammability ( F index ) of the PLA/IFR. The TGA test revealed that La 2 O 3 changed the degradation behavior of the PLA/IFR, enhanced the thermal stability of the PLA/IFR at high temperature and increased the char residue. The morphological structures observed by SEM demonstrated that La 2 O 3 effectively help to form more continuous and compact intumescent char layer on the surface. The LRS results indicated that higher graphitization degree of the residue char was formed. The EDS and XPS results illustrated that the existence of La 2 O 3 promoted to remain more P and O in the char layer to form more crosslinking structure to improve barrier properties of the char layer. [ABSTRACT FROM AUTHOR]

The magnetic refrigeration (MR) based on magnetocaloric effect (MCE) is a key technique, since it possesses ideally higher performance than the traditional gas compression technology. However, the lack of MR materials with excellent MCE performance is a bottle-neck for practical MR applications. Herein, we systematically report the structural properties using powder X-ray diffraction and scanning electron microscope as well as the magnetic and magnetocaloric properties through the magnetization measurements of four rare-earth (RE) ruthenate RE 3 RuO 7 (RE = Pr, Nd, Gd and Tb) compounds. Light RE -based Pr 3 RuO 7 and Nd 3 RuO 7 compounds form an orthorhombic Cmcm structure, while heavy RE based Gd 3 RuO 7 and Tb 3 RuO 7 compounds crystallize in an orthorhombic P 2 1 nb structure. The magnetic phase transition of all the present compounds are confirmed to be of the first-order type with T N of 52, 15, 11 and 12 K for Pr 3 RuO 7 , Nd 3 RuO 7 , Gd 3 RuO 7 and Tb 3 RuO 7 compounds, respectively. The related MCE parameters including the maximum isothermal magnetic entropy change, temperature-averaged entropy change (5 K lift), and refrigerant capacity with the magnetic field change of 0–5 T were computed to be 1.35 J/kgK, 1.31 J/kgK, and 27.4 J/kg for Pr 3 RuO 7 , to be 2.18 J/kgK, 2.04 J/kgK, and 25.6 J/kg for Nd 3 RuO 7 , to be 8.12 J/kgK, 7.90 J/kgK, and 124.6 J/kg for Gd 3 RuO 7 , and to be 7.78 J/kgK, 7.49 J/kgK, and 128.8 J/kg for Tb 3 RuO 7 , respectively. [ABSTRACT FROM AUTHOR]

CsCl-type HoZn undergoes two successive magnetic phase transitions: (i) paramagnetic to ferromagnetic (FM) at T C ∼ 72 K and (ii) a spin reorientation (SR) at T SR ∼ 26 K. Magnetization and modified Arrott plots indicate that HoZn undergoes a second-order magnetic phase transition around T C . The obtained critical exponents have some small deviations from the mean-field theory, indicating a short range or a local magnetic interaction which is properly related to the coexistence of FM and SR transitions at low temperature. Two successive magnetic transitions in HoZn induce one broad pronounced peak together with a shoulder in the temperature dependence of the magnetic entropy change −Δ S M ( T ) curves, resulting in a wide temperature range with a large relative cooling power ( RCP ). For a field change of 0–7 T, the maximum value of −Δ S M is 15.2 J/kg K around T C with a large RCP value of 1124 J/kg. The large reversible magnetocaloric effect (MCE) and RC indicate that HoZn is a good candidate for active magnetic refrigeration. [ABSTRACT FROM AUTHOR]

We herein fabricated the (Dy 0.25 Ho 0.25 Er 0.25 Tm 0.25) 2 Cu 2 In high-entropy (HE) compounds and systematically determined its structural, magnetic, and magnetocaloric properties. The (Dy 0.25 Ho 0.25 Er 0.25 Tm 0.25) 2 Cu 2 In HE compound was found to crystalize in a tetragonal Mo 2 B 2 Fe type structure (P4/ mbm space group) and undergoes typical second order type magnetic transition. Large MCE and prominent cryogenic magnetocaloric performances were observed in (Dy 0.25 Ho 0.25 Er 0.25 Tm 0.25) 2 Cu 2 In HE compound. The evaluated values of magnetic entropy change and refrigerant capacity of (Dy 0.25 Ho 0.25 Er 0.25 Tm 0.25) 2 Cu 2 In HE compound under magnetic field change of 0–7 T are 17.1 J/kgK and 398.0 J/kg which are comparable with the reported candidate materials for cryogenic magnetic cooling, making the present (Dy 0.25 Ho 0.25 Er 0.25 Tm 0.25) 2 Cu 2 In HE compound also considerable for practical applications. • The (Dy 0.25 Ho 0.25 Er 0.25 Tm 0.25) 2 Cu 2 In HE compound was fabricated. • The structural, magnetic, MPT and MC properties were investigated. • The present HE compound is considerable for cryogenic magnetic cooling. [ABSTRACT FROM AUTHOR]

• The gallides RE 2 Rh 3 Ga (RE = Gd, Dy, Ho, Er) compounds are fabricated. • The structural, MPT and magnetocaloric properties in RE 2 Rh 3 Ga were studied. • The present RE 2 Rh 3 Ga compound are considerable for cryogenic MR. We herein provide an experimental investigation of the gallides RE 2 Rh 3 Ga (RE = Gd, Dy, Ho, Er) regarding their magnetic properties and magnetocaloric effect (MCE). All of these RE 2 Rh 3 Ga intermetallic compounds crystallized with the Mg 2 Ni 3 Si type structure, space group R– 3 m and are ordered magnetically at low temperatures. Large reversible MCEs around their own ordering temperature were observed in all RE 2 Rh 3 Ga compounds and their magnetocaloric parameters including the maximum magnetic entropy change, refrigerant capacity, and temperature-averaged entropy change are comparable to those of some recently reported candidate materials with prominent performances, making them considerable for cryogenic MR applications. [ABSTRACT FROM AUTHOR]