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Phase structure and microstructure of (Nd1-xCex)13.4Fe79.9B6.7 (x = 0.0–1.0) alloys that were prepared via the arc-melting method were studied experimentally in this work. The results reveal that (Nd1-xCex)13.4Fe79.9B6.7 alloys annealed at 1173 K for 360 h are a single (NdCe)2Fe14B phase with the tetragonal Nd2Fe14B-typed structure (space group P42/mnm). The formation of continuous (NdCe)2Fe14B solid solution phase in annealed (Nd1-xCex)13.4Fe79.9B6.7 alloys was confirmed. On the other hand, magnetic measurements exhibit that the coercivity, remanence, maximum magnetic energy product, and Curie temperature of (Nd1-xCex)13.4Fe79.9B6.7 ribbons that were fabricated by melt spinning technology decrease gradually with increasing Ce content, which results from the substitution of Nd by Ce in Nd2Fe14B phase due to inferior intrinsic magnetic properties of Ce2Fe14B phase.

Gd1−xNdxMn2Ge2 compounds with x = 0.3 and 0.4 were prepared by arc melting and crystallized in the ThCr2Si2-type structure with the space group I4/mmm based on X-ray powder diffraction (XRD) results. Magnetic transition and magnetocaloric effect (MCE) of the Gd1−xNdxMn2Ge2 compounds were investigated by magnetic measurements on a physical property measurement system (PPMS). Gd0.7Nd0.3Mn2Ge2 compound exhibits complicated magnetic transitions at around 63 K (Tcomp), 86 K (T1), 136 K (TC), 260 K ( $T_{\mathrm {N}}^{\text {inter}}$ ), and 347 K ( $T_{\mathrm {C}}^{\text {inter}}$ ), respectively, while Gd0.6Nd0.4Mn2Ge2 compound shows a spin re-orientation transition at about 52 K. Combined with isothermal magnetization curves and the Maxwell relation, the maximum magnetic entropy changes of Gd0.7Nd0.3Mn2Ge2 and Gd0.6Nd0.4Mn2Ge2 were calculated to be 4.31 and 5.15 J kg− 1 K− 1 under the applied magnetic field changing from 0 to 5 T, respectively.

Two fluorinated photoinitiators, named as 2959-IPDI-F and 2959-IPDI-F-HDDA, were successfully synthesized and characterized. The photochemical behaviors of 2959-IPDI-F and 2959-IPDI-F-HDDA were investigated through the photolysis and polymerization of 1, 6- hexanediol diacrylate. The oxygen inhibition was obviously decreased due to the migration of fluorinated photoinitiator to the surface, which was proved through XPS, SEM-EDS. The higher concentration of photoinitiator at top layer accelerated the polymerization rate and reduced the oxygen sensitivity. A fluorine element enriched and folded surface could be developed only through simple photopolymerization initiated by fluorinated photoinitiators.

Drilling and blasting is one of the most widely-used methods for large-scale excavation in rocks and soils. However, rock blasting can induce many adverse effects, and the typical influence of rock blasting on the surrounding environment is illustrated in Fig. 1. Explosion induces ground and structures vibration1., 2. and annoying noise. When the explosive is detonated, an extremely high-pressure pulse is generated, which is transmitted into rock mass adjacent to the blast hole, producing a dilatational wave that propagates away from the charge. Stress waves due to blasts may cause damage to the surrounding rock and, furthermore, when the wave reaches a free face or open fissure (non-transmission), it will be reflected and converted into a tensile wave, which may produce tensile cracking and spalling if the tensile strength of the rock is exceeded by the tensile wave.3., 4. Also, due to the fact that some rock blasting projects are close to the inhabitant area, the surrounding buildings may be damaged due to blasting-induced ground vibration if large stress wave propagates in the soil foundation and shock wave propagating through the air.5 Disruption of some business activities, possible structural damage and emotional-traumatized residents are the problems that need to be addressed.2., 6. Therefore, the influence of ground vibrations on surrounding buildings, sensitive devices and people in urban environments is a significant consideration in obtaining project approvals.

Phase equilibria and solidification behavior of the La-Pr-Fe and Ce-Pr-Fe ternary systems were carried out through experimental investigation and thermodynamic calculation. Phase transition temperatures and solidification microstructure of La-Pr-Fe and Ce-Pr-Fe ternary alloys were studied by means of differential thermal analysis (DTA) and scanning electron microscopy with energy dispersive spectra (SEM-EDS). Based on the experimental results determined in this work and reported in the literature, the La-Pr-Fe and Ce-Pr-Fe ternary systems were calculated by the CALPHAD method, and reasonable thermodynamic parameters of these two ternary systems were obtained in this work. The calculated isothermal section and vertical section of the La-Pr-Fe and Ce-Pr-Fe ternary systems are in good agreement with the experimental results. The solidification processes of as-cast La-Pr-Fe and Ce-Pr-Fe ternary alloys were analyzed through thermodynamic calculation with Scheil model, which is satisfactorily consistent with the experimental solidification microstructure.

A novel emulsified photoinitiator (named as OP10-IPDI-2959) was prepared by the reaction of isophorone diisocyanate (IPDI) with 2-hydroxy-4′-(2-hydroxyethoxy)-2-methylpropiophenone (Ir-2959) and nonylphenol polyoxyethylene ether (OP-10). The structure of OP10-IPDI-2959 was characterized by FT-IR, 1H NMR, UV–vis and high-resolution mass spectrometry. The photochemical behavior of OP10-IPDI-2959 was investigated through the photolysis and polymerization of neopentyl glycol diacrylate (NPGDA), mixture of epoxy acrylate resin and 1,6-hexanediol diacrylate (HDDA). Under irradiation of UV light, the OP10-IPDI-2959 has similar photochemical properties with the Ir-2959. Combined with benzophenone, the photoinitiated rate of OP10-IPDI-2959 is higher than that of Ir-2959. The polyoxyethylene fragment of OP10-IPDI-2959 is not only an alternative to toxic amine as hydrogen donor, but also a hydrophilic unit for interface between oil and water. The OP10-IPDI-2959 can effectively emulsify the epoxy acrylate resin and 1,6-hexanediol diacrylate mixture to form low viscosity emulsion. Compared with Ir-2959, OP10-IPDI-2959 has good photoinitiation activity, lower migration and good water emulsification performance.

Thermodynamic re-assessment of the Fe-Tm and Fe-Ho binary systems were carried out with the help of the CALPHAD method based on the previous optimizations and the critical review of the available experimental information in the published literature. The substitutional solution model was used to describe liquid phase and fcc-Fe, bcc-Fe, hcp-Tm, bcc-Ho and hcp-Ho solid solution phases and their excess terms of Gibbs energies were expressed with the Redlich-Kister polynomial. The intermetallic compounds, Fe17Tm2, Fe23Tm6, Fe3Tm, Fe2Tm, Fe17Ho2, Fe23Ho6, Fe3Ho and Fe2Ho, were treated as stoichiometric compounds considering the experimental heat capacity of two intermetallic compounds (Fe2Tm and Fe2Ho) in the low temperature range. Self-consistent thermodynamic parameters to describe the Gibbs energies of various phases in the Fe-Tm and Fe-Ho binary systems were obtained finally. The calculated results in this work are in good agreement with available phase equilibira data and thermodynamic data.

A novel polymerizable photoinitiator (HEMA-IPDI-2959) was synthesized through the reaction of Isophorone diisocyanate with 2-hydroxyethyl methacrylate and Irgacure 2959. The molecular structure of HEMA-IPDI-2959 was characterized through 1 H NMR, FT-IR, UV–vis and a high-resolution mass spectrum. The UV–vis spectrum and 1 H NMR of the photolysis product of HEMA-IPDI-2959 suggest HEMA-IPDI-2959 to be a type I photoinitiator. Furthermore, HEMA-IPDI-2959 and Irgacure 2959 were also used to initiate the polymerization of 1,6-hexanediol diacrylate and Trimethylolpropane triacrylate. Results suggest that HEMA-IPDI-2959 has a higher reactivity with a lower migration rate relative to Irgacure 2959.

The Sm-Ni-Fe ternary system has been investigated at 773 K by means of powder x-ray diffraction, metallography and scanning electron microscopy equipped with energy dispersive x-ray spectroscopy. The isothermal section consists of 16 single-phase regions, 29 two-phase regions and 14 three-phase regions. The influence of Fe-doping on the structure and the microwave absorption properties of the SmNi5 compound has been systematically studied. The homogeneity range in Sm16.67Ni83.33−xFex was determined as x = 16.67. The lattice parameters were found to gradually increase and the particle size become much finer with the increase of Fe concentration. All the samples exhibited good microwave absorption properties in the X-band (8–12 GHz). The highest reflection loss of the Sm16.67Ni83.33−xFex (x = 0.0, 5.0, 10.0,15.0, 16.67) alloys are −10.12 dB, −10.39 dB, −16.44 dB, −20.69 dB, and −43.05 dB at 6.96 GHz, 7.92 GHz, 8.56 GHz, 10.04 GHz, and 11.08 GHz, respectively. The absorption peak shifted towards the higher frequency region with the increasing amount of Fe substitution.

In this work, Fe-Pr alloys and Fe-Nd alloys were investigated experimentally by means of thermal analysis. The temperatures of the invariant reactions and liquidus in the Fe-Pr and Fe-Nd binary systems were measured. Based on the experimental results determined in this work and the critical review of the available experimental data in published literature, the Fe-Pr and Fe-Nd binary systems were re-assessed thermodynamically using the CALPHAD method. The solution phases including liquid, bcc, fcc and dhcp are modeled by the substitutional solution model and their excess Gibbs energies are expressed with the Redlich-Kister polynomial. The intermetallic compounds, Fe17Pr2, Fe17Nd2 and Fe17Nd5 are treated as intermetallic compounds. The self-consistent thermodynamic parameters obtained finally to describe the Gibbs energies of various phases in the Fe-Pr and Fe-Nd binary systems can be used to reproduce well the phase equilibria and thermodynamic data.

A novel bifunctional photoinitiator (named as TX-EG-IPDI-2959) with thioxanthone and hydroxyalkylphenone moieties was synthesized by the reaction of isophorone diisocyanate with Irgacure 2959 and 2-(2-hydroxyethoxy) thioxanthone. The molecular structure of TX-EG-IPDI-2959 was characterized by 1H NMR, high-resolution mass spectroscopy, UV–vis and FT-IR. The photochemical behavior of TX-EG-IPDI-2959 was investigated through the photolysis and polymerization of butyl acrylate by UV–vis and HRMS. Compared with the combination of Irgacure 2959 and 2-(2-hydroxyethoxy) thioxanthone, the C C bond cleavage of hydroxyalkylphenone to produce free radical fragments was effectively done under the irradiation of visible LED light. The obvious intramolecular synergistic effect between the hydroxyalkylphenone and thioxanthone moieties has been confirmed based on HRMS analysis of photobleach and photopolymerization. In addition, the photopolymerization kinetic of an UV gel and trimethylolpropane triacrylate initiated by TX-EG-IPDI-2959 were also investigated. The plausible photochemical reaction mechanism of TX-EG-IPDI-2959 was proposed.

A series of polycrystalline Bi1−xLaxFeO3 (0≤x≤1.00) solid solution were synthesized by sol–gel method. The effects of lanthanum concentration on the phase formation, phase transition and magnetic properties were studied. The XRD results displayed that there is a clear indication of structural modification and symmetry change brought about by La doping. At room temperature the crystal structure of the solid solution transforms from rhombohedral R3c (x≤0.15) to tetragonal P4mm (0.15

Nd-Fe-B-based alloys as sintered Nd2Fe14B-typed permanent magnets have been studied extensively due to their excellent magnetic properties. In this work, the experimental information on the corresponding phase equilibria of the Nd-Fe-B ternary system in the published literature is reviewed first. The key Nd-Fe-B alloys annealed at 873 and 1073 K were then investigated experimentally to determine the phase equilibria of the system using x-ray diffraction technique and scanning electron microscope (SEM) with energy dispersive spectrometry (EDS). The ternary intermetallic compound, Nd2Fe14B with space group P42/mnm as Nd2Fe14B structure type, NdFe4B4 with space group Pccn as REl.11Fe4B4 structure type and Nd5Fe2B6 with space group R $$ \overline{3} $$ m as Pr5Co2B6 structure type were confirmed at 873 and 1073 K. The binary intermetallic compound Nd5Fe17 is stable at 873 K, while it was not found at 1073 K. The phase equilibria of the Nd-Fe-B ternary system consists of 14 single-phase regions, 28 two-phase regions and 16 three-phase regions at 873 K, while there are 8 single-phase regions, 14 two-phase regions and 7 three-phase regions at 1073 K except for the B-rich part.

The structure and electrochemical properties of La0.8–xCexPr0.1Nd0.1B5 (B5 ≡ Ni3.8Co1.1Mn0.1; x = 0, 0.1, 0.2, 0.3) hydrogen storage alloys have been investigated. The results show that all alloys consist of CaCu5-type single phase. The maximum discharge capacity of the alloy electrodes decreases from 368.7 mA h g–1 (x = 0) to 294.9 mA h g–1 (x = 0.30), the cyclic stability (S100) increases from 37.6% (x = 0) to 69.8% (x = 0.20) after 100 charge/discharge cycles, and the HRD1200 first increases from 69.5% (x = 0) to 85.2% (x = 0.20), then decreases to 80.8% (x = 0.30). Meanwhile, the electrochemical kinetic characteristics of the La0.8‒xCexPr0.1Nd0.1B5 alloy electrodes are also improved by increasing Ce content.

The solidification microstructure and phase transition of ten La-Nd-Fe alloys were studied experimentally by scanning electron microscopy (SEM) with energy dispersive x-ray spectroscopy (EDS) and differential thermal analysis (DTA). Phase compositions and phase transition temperatures of La-Nd-Fe alloys were measured and the formed phases were identified. The solidification behavior of La-Nd-Fe alloys was analyzed based on the experimental results of both solidification microstructure and phase transitions with the reported Nd-Fe, La-Fe and La-Nd sub-binary phase diagrams. The results indicated that the solidification processes of all La-Nd-Fe alloys begin with the precipitation of primary phase fcc(γ-Fe) and then follow by the formation of bcc(α-Fe) and/or Fe17Nd2 phases through different peritectic reactions. The solidification microstructure of three Fe65La29Nd6, Fe65La25Nd10 and Fe65La22Nd13 alloys presents three-phase microstructure with bcc(α-Fe), Fe17Nd2 and fcc(La,Nd) phases, while that of three Fe65La19Nd16, Fe65La9Nd26 and Fe65La15.5Nd19.5 alloys shows three-phase microstructure with bcc(α-Fe), Fe17Nd2 and dhcp(La,Nd) phases. The two-phase micorstructure with Fe17Nd2 and dhcp(La,Nd) ohases was formed in the solidification microstructure of four Fe65La12Nd23, Fe65La6.5Nd28.5, Fe65La4Nd31 and Fe65La1.5Nd33.5 alloys. Moreover, no stable ternary intermetallic compound was found in the present experiments. The solidification microstructure and phase transition of La-Nd-Fe alloys would provide a basis for the design of La-Nd-Fe-B magnetic alloys.

The phase formation of the (Nd0.70Pr0.30−xCex)2.28Fe13.58B1.14 (x = 0.10, 0.15, and 0.20; hereafter defined as Pr20Ce10, Pr15Ce15 and Pr10Ce20, respectively) and (Nd0.60Pr0.40−yCey)2.28Fe13.58B1.14 (y = 0.10, 0.20, and 0.30; hereafter defined as Pr30Ce10, Pr20Ce20 and Pr10Ce30, respectively) alloys that were prepared via the arc-melting method was investigated experimentally. The x-ray diffraction results revealed that all alloys annealed at 1173 K for 360 h consisted of a (NdPrCe)2Fe14B main phase with a tetragonal Nd2Fe14B-typed structure (space group P42/mnm) and an α-Fe minor phase, except for the Pr10Ce30 alloy, which contained an additional CeFe2 phase. The magnetic properties of the (Nd0.70Pr0.30−xCex)2.28Fe13.58B1.14 and (Nd0.60Pr0.40−yCey)2.28Fe13.58B1.14 ribbons that were prepared by melt spinning were examined. The remanence (Br) and maximum magnetic energy product ((BH)max) of the (Nd0.70Pr0.30−xCex)2.28Fe13.58B1.14 ribbons increased first and then decreased, whereas the coercivity (Hcj) of the ribbons increased with an increase in Ce content. The Br and (BH)max of the (Nd0.60Pr0.60−yCey)2.28Fe13.58B1.14 ribbons increased, whereas the Hcj of the ribbons decreased gradually with an increase in Ce content. This changed behavior of magnetic properties is attributed to the variation of volume fraction of the α-Fe phase and different phase formations in the melt-spun ribbons. The Curie temperatures (Tc) of all ribbons decreased slightly with Ce substitution, which results from the lower Curie temperatures of Pr2Fe14B and Ce2Fe14B. The Pr10Ce30 ribbon with a higher Ce content exhibited optimal magnetic properties (Br = 9.71 kGs, Hcj = 13.09 kOe, (BH)max = 18.78 MGOe), which indicates that suitable magnetic properties of the Nd–Pr–Ce–Fe–B melt-spun ribbons can be achieved by alloy-composition and phase-formation design.

Phase equilibria and thermodynamic properties of Nd-Fe-B-based alloys are fundamental to design novel Nd-Fe-B-based permanent magnets with outstanding magnetic properties and lower costs. In order to develop thermodynamic database of multi-component Nd-Fe-B-based alloys with the rare earth (RE) metals, in this work, the RE-B (RE = Ce, Dy, Lu) binary systems were assessed thermodynamically using the CALPHAD method based on the available phase diagram and thermodynamic data reported in the literature. In the thermodynamic modeling, the solution phases including liquid, bcc, fcc, hcp and rhombohedral, are described as the substitutional solution model and their excess Gibbs energies are described by Redlich-Kister polynomial. The binary intermetallic compounds, CeB4, CeB6, DyB2, DyB4, DyB6, DyB12, DyB66, LuB2, LuB4, LuB12 and LuB66, are treated as the stoichiometric compounds considering the experimental heat capacities and enthalpy increments of some intermetallic compounds. The calculated results are in good agreement with the reported experimental data.

The phase relations in the pseudo-binary Nd2Fe14B–Pr2Fe14B system were investigated and constructed by means of X-ray powder diffraction (XRD), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS). The results revealed that similar to the end-members of the Nd2Fe14B–Pr2Fe14B system form a continuous solid solutions, all intermediate (Nd1−xPrx)2Fe14B samples belong to tetragonal Nd2Fe14B-type structure (space group P42/mnm). The lattice parameter a almost remains the same, and the lattice parameter c and unit-cell volume V increase linearly with an increase of Pr concentration. Based on the results of DTA measurements and X-ray powder diffraction examinations, the tentative phase diagram of the Nd2Fe14B–Pr2Fe14B isopleth has been constructed.

The series of polycrystalline Bi 1− x La x FeO 3 (0 ⩽ x ⩽ 0.50) ceramic powders was successfully synthesized by sol–gel method in this paper. X-ray diffraction and Rietveld crystal structure refinement software (FULLPROF) were used as complementary method to study structure and hyperfine interactions of the samples. It was a clear indication of structural modification and symmetry changes brought about by La doping. The BFO is crystallized in rhombohedrally distorted perovskite structure with space group R3c for x ⩽ 0.10. With an increase of La content, within the range x = 0.10–0.20 a structural phase evolutes from rhombohedral to cubic Pm 3 ¯ m structure, and then transits to orthorhombic Pbnm structure on further increasing the La-doping to x = 0.50. The magnetization of La-doped samples is improved with the increase of La content. The coercive field (Hc) increases remarkably with an increase in La doping and x = 0.50 exhibits the highest Hc (20.2 kOe at room temperature) reported so far in any rare earth doped BFO, which will have a great potential for practical application in non-volatile memory devices. Moreover, high-field magnetization and remanence (Mr) increase with La doping content due to the gradual change in spin cycloid structure.

In the present work, sixteen Mn–In alloys were investigated experimentally by means of thermal analysis and X-ray diffraction techniques. The temperatures of the invariant reactions and liquidus in the Mn–In binary system were determined. Based on the experimental results obtained in the present work and the critical review of the available experimental data from the published literature, the Mn–In binary system was assessed thermodynamically using the CALPHAD method. The solution phases including liquid, α-Mn, β-Mn, γ-Mn, δ-Mn and tetragonal_A6(In), are modeled by the substitutional solution model and their excess Gibbs energies are expressed with the Redlich–Kister polynomial. The intermetallic compound, InMn 3 , is treated as a stoichiometric compound. A set of self-consistent thermodynamic parameters obtained finally to describe the Gibbs energies of various phases in the Mn–In binary system can be used to reproduce well the phase equilibria and thermodynamic data.

The Nd-B binary system was re-assessed thermodynamically based on the available experimental information from literatures using the CALPHAD method. The solution phases including liquid, fcc, bcc and dhcp, were modeled as substitutional solutions and their excess Gibbs energies were expressed by the Redlich-Kister polynomial. Combined with the previous assessments of the Fe-Nd and the Fe-B binary systems, the thermodynamic description of the Nd-Fe-B ternary system was performed on the basis of the reported experimental information. The solubility of third element in the binary intermetallic compounds was not taken into account due to the lack of experimental data. A set of self-consistent thermodynamic parameters formulating the Gibbs energies of various phases in the Nd-Fe-B ternary system was obtained in the present work. The liquidus projection, several isothermal sections and vertical sections of this ternary system were calculated, which are in reasonable agreement with the reported experimental data.

In this work, twenty-four Mn-Dy and Mn-Ho alloys were investigated experimentally using the differential thermal analysis (DTA), scanning electron microscopy (SEM) and electronic probe microanalysis (EPMA) to study phase equilibria of the Mn-Dy and Mn-Ho binary systems. The temperatures of some invariant reactions and liquidus in the Mn-Dy and Mn-Ho binary systems were determined. Based on the experimental results obtained in the present work and the critical evaluation of the experimental data reported in the literature, the Mn-Dy and Mn-Ho binary systems were calculated using the CALPHAD method. In the thermodynamic calculation, the solution phases including liquid, α(Mn), β(Mn), γ(Mn), δ(Mn), α(Dy), β(Dy), α(Ho) and β(Ho), are treated as the substitutional solution model with the Redlich-Kister formula. The intermetallic compounds, Mn2Dy, Mn12Dy, Mn23Dy6, Mn2Ho, Mn12Ho and Mn23Ho6, are modeled as the stoichiometric compounds. Self-consistent thermodynamic parameters were obtained finally to describe the Gibbs energies of various stable phases in the Mn-Dy and Mn-Ho binary systems. The calculated results reproduce well the phase equilibria and thermodynamic properties.

Impurity transport in the scrape-off layer (SOL) has been studied in ohmically heated discharges of the HL-2A tokamak based on space-resolved vacuum ultraviolet spectroscopy. The vertical profile (from the plasma center to the lower X-point) of carbon emissions of CIII (977 A: 2s2 1S0-2s2p ) and CIV (1548 A: 2s 2S-2p 2P) as well as the ratio of CIV to CIII were measured to investigate the edge impurity transport with relation to impurity source locations and sputtering characteristics. The experimental result shows that the impurity profile in the SOL has been clearly changed against different source locations. The emission of CIII and CIV from the mid-plane is stronger than that from the X-point when the impurity source is located at the divertor plate. The profile becomes flat as a result. When the impurity source changes to the dome source, the profile clearly changes to a slightly peaked one, indicating the edge carbon emission at the X-point is stronger than the mid-plane. The change to the limiter source makes the profile further peaked by increasing the carbon emission at the X-point. In the case of the dome impurity source, the intensity of CIII/ne and CIV/ne, normalized to line-averaged electron density, ne, decreases with ne at low ne (ne ⩽ 2.6 × 1019 m−3) and becomes saturated at high ne (ne > 2.6 × 1019 m−3). In contrast, the ratio of CIV to CIII increases with ne at low ne and starts to decrease at high ne. A numerical simulation with 3D edge plasma transport code, EMC3-EIRENE, suggests that a poloidal asymmetry in the impurity flow profile and an enhanced physical sputtering play an important role in the edge impurity distribution, particularly in the screening efficiency of C2+ and C3+ ions in the SOL region of the HL-2A tokamak.