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Increasing zinc (Zn) concentration in wheat grain is important to minimize human dietary Zn deficiency. This study aimed to investigate the effect of foliar Zn and soil nitrogen (N) applications on the accumulation and distribution of N and Zn in grain pearling fractions, N remobilization, and the relationships between nutrient concentration in the vegetative tissues and grain or its fractions in two cropping years in the North China Plain. The results showed a progressive decrease in N and Zn concentrations from the outer to the inner parts of grain, with most of the accumulation in the core endosperm. Foliar Zn application significantly increased N concentration in the pericarp, and soil N application increased N concentration in each grain fraction. Both treatments significantly increased core endosperm Zn concentration. Foliar Zn had no effect on grain N and Zn distribution. Soil N application made N concentrated in the aleurone, promoted Zn translocation to the core endosperm and also increased N remobilization and its efficiency from the shoot to the grain, but no improved contribution to grain was found. N concentration in grain and its fractions were positively correlated with N in vegetative organs at anthesis and maturity, while positive correlations were obtained between N concentration in the pericarp and progressive central area of the endosperm and Zn concentration in the core endosperm. Thus, foliar Zn and soil N applications effectively increased yield and N and Zn concentrations in the wheat grain, particularly in the endosperm, and could be promising strategies to address Zn deficiency.

In this paper, the hydrogen diffusion behavior and hydrogen induced delayed fracture (HIDF) of Q-P980 (Q-P: Quenching and Partitioning) and MS980 (MS: Martensitic steel) steels were investigated using hydrogen penetration, slow strain rate tensile (SSRT) tests, thermal desorption spectroscopy (TDS) tests, fracture analysis, and microstructural examination in this paper. The austenite in Q-P980 is massive retained-austenite (RA) with low stability. The TRIP (Transformation Induced Plasticity) effect will occur in the process of strain and change into high carbon martensite. HIDF is caused by a substantial amount of surplus hydrogen being enriched at the border and flaws. The fracture has a broad cleavage surface and is a typical quasi-cleavage fracture. MS980 has been sufficiently tempered, resulting in a substantial quantity of distributed spherical cementite (150nm) precipitating around the lath martensite. This size and form of cementite may successfully trap hydrogen while maintaining the material’s mechanical characteristics. And tempering can effectively reduce the local stress level of steel, so MS980 has a very low HE susceptibility. HIDF is related to local stress and hydrogen accumulation. We suppose that Z is a constant and Z C is a critical value which associated to σ and C H (the local stress and local hydrogen concentration), rising as σ and C H rises. The atomic bonds at the crack tip, lattice position and the phase interface will fracture when Z C reaches a particular value Z. Tempering to minimize local stress and carbide precipitation to capture hydrogen are two strategies for reducing hydrogen embrittlement (HE) susceptibility, particularly for dislocation strengthened steel. Microalloying elements can generate precipitates that function as hydrogen traps and obstruct the HELP (Hydrogen Enhanced Localized Plasticity) process, lowering local stress and hydrogen accumulation.

The extruded Mg–7Y–1Nd–0.5Zr (wt%) alloy were performed to the same strain hot rolling with different temperatures. The microstructure and texture evolution of the sheets were investigated by optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and electron back-scattered diffraction (EBSD). The results indicate that the microstructure becomes homogeneous after hot rolling process and precipitated phase distributes at grain boundaries along rolling direction. With the increase in rolling temperature, the grains of sheet grow up. The sheet rolling at 400 °C is composed of recrystallization grains, the necklace of the precipitated phase in the grain boundaries and excessive dislocations. The structure of necklace of the precipitated phase is fcc structure with lattice constant of a = 0.75 nm. With rolling temperatures increasing from 400 to 450 °C, the content of recrystallized grains in volume fraction with relatively random orientations increases significantly. Compared with the rolling process at 400 °C, the amount of precipitated phases is reduced at the grain boundary, and the precipitated phase begins to appear in the grain interior when rolling at 450 °C. The structure of the precipitated phase is fcc with lattice constant of a = 2.22 nm. The recrystallization grains begin to grow in the rolling process at 500 °C. The basal texture is obviously produced during the rolling process at 400 and 450 °C; however, the basal texture is weak in the rolling process at 500 °C. The pole point of the (0002) pole figure is concentrated in the center. It can be seen that the basal surface is parallel to RD–TD surface of the rolling sheets. Compared with as-extruded alloy, the basal texture is significantly enhanced with a small increase in basal texture intensity from 6.127 to 7.175, and $$(10\bar{1}0)$$ and $$(11\bar{2}0)$$ textures change to random textures.

The effects of systematic variation of Mg and Cu contents (Mg: ~1.5, 2.0, and 2.5, Cu: ~1.5, 2.0, 2.5, and 2.9 wt%) on the microstructures and mechanical properties of high-Zn (8.5 wt%) Al–Zn–Mg–Cu alloys are investigated. Fracture toughness is experimentally approached by the Kahn tear test. Results showed that, under same ageing condition, the conductivity, hardness, strength and toughness of the designed alloys are primarily determined by Mg content: the higher the Mg content, the higher the hardness and strength, but the lower the conductivity and toughness. Increasing Cu content can produce a similar phenomenon, but with weak effects compared with Mg. The experiments and thermodynamic/kinetic simulation indicate that, increasing Mg/Cu content can improve the volume fraction of matrix precipitates, so as to improve the strength and hardness, and the effects of Mg are stronger than Cu. Additionally, increasing Mg content can somewhat reduce the sizes of the matrix precipitates especially in overaged condition, which is also good for the strength and hardness. However, with increasing Mg content the area fraction of the grain boundary precipitates (GBPs) and the yield stress contrast between grain interiors and precipitate free zones (PFZs) at grain boundary can be increased greatly, consequently promoting intergranular fracture and decreasing toughness. For the alloys with low/middle Mg content (e.g., 1.5/2.0 wt%), increasing Cu content will improve the yield stress contrast between grain interiors and PFZs as well as the recrystallization degree, so that intergranular fracture will be promoted for toughness reduction. For the alloys with high Mg content (e.g., 2.5 wt%), the increased undissolved phases induced by high Cu content will promote fracture at/near coarse constituent particles, favoring further toughness reduction.

The microstructures and mechanical properties of Mg–7.0 wt%Y–1.0 wt%Nd–0.5 wt%Zr magnesium alloy were investigated both in as-cast condition and after homogenization heat treatment by differential scanning calorimetry (DSC), optical microscopy (OM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and hardness measurement. The results indicate that the as-cast alloy consists of α-Mg matrix, Mg24Y5 and Mg41Nd5 phases, which are eutectic phases (cubic Y-rich phase). With the increase in homogenization temperature and time, the Mg24Y5 and Mg41Nd5 phases are completely dissolved into matrix, and only yttrium of intermetallic compounds leaves around boundary. After homogenization heat treatment, the elements distributed uniformly and the grains grow up not obviously, only yttrium element of intermetallic compounds left around boundary. The optimum homogenization condition is at 537 °C for 16 h. The mechanical properties are improved after homogenization, with tensile strength of σb = 181 MPa, yielding strength of σ0.2 = 144 MPa and elongation of δ = 5.5 %, which are better than those of as-cast alloy.

Optical microscopy (OM), scanning electronic microscopy (SEM) and X-ray diffraction (XRD) were performed to investigate the influence of homogenization on the microstructures of the Mg-7Gd-5Y-1MM (Ce-rich RE)-0.5Zr magnesium alloy. The results indicated that α-Mg, Mg 24 (GdY) 5 phase, Mg 5 (GdY) phase and Mg 12 MM phase coexisted together in as-cast alloy; the microstructures were largely characterized by α-Mg matrix and gray globular or elliptic ball Mg 12 MM phase, in addition to those with cubic block Mg 24 (GdY) 5 phase after homogenization; the reasonable homogenization regime was maintained at 530 °C for 32 h.

Microstructures and mechanical properties of Mg–7Gd–3Y–1Nd–0.5Zn–0.5Zr (wt%) alloy before and after homogenization at 520 °C were systematically studied. The results indicated that the microstructure of as-cast alloy mainly consisted of α-Mg, (Mg,Zn) 3 RE phase, Mg 5 (RE, Zn) phase and some fine needle structures near the grain boundary; the (Mg, Zn) 3 RE and Mg 5 (RE, Zn) phases had a face centered cubic (fcc) structure and were isomorphous with β 1 and β phases; the fine needle structures were an stacking fault. Heat treatment at 520 °C caused the dissolution of not only the (Mg, Zn) 3 RE phase and Mg 5 (RE, Zn) eutectic phases, but also the stacking fault into the α-Mg matrix; no long period stacking ordered (LPSO) phases were observed. The tensile test at room temperature suggested that the ultimate tensile strength (UTS), yield strength (YS) and elongation of the as-cast and as-homogenized were 170 MPa, 129 MPa and 238 MPa, 125 MPa, and the elongations were 3% and 12%, respectively. Fracture analysis of the as-cast alloys revealed that micro-cracks initiated in the grain boundary, which belonged to intergranular fracture, while the micro-cracks mainly appeared in the grain interior; the fracture mode was transgranular fracture after homogenization.

As an intermedia between cold and thermal plasmas, warm plasma generated by gliding arc (GA) discharge possesses high conversions and high energy efficiencies for CO2 conversion. However, there is little understanding for the arc characteristics in CO2-based atmosphere and reaction mechanism of CO2 in GA plasma from experimental approach. For this purpose, a magnetically driven GA plasma with a constant length of arc is designed to study GA characteristics and reaction mechanism by changing H2/CO2 molar ratio (from pure CO2 to pure H2). In the entire range of H2/CO2 ratio, the arc channel shows a glow-like feature. The plasma parameters are arc temperature of 2200–3600 K, electron density of ~1.6 × 1014 cm−3 and electron temperature of ~3 eV. From pure CO2 to pure H2, arc diameter decreases from 1.3 to 0.6 mm, whereas rotational frequency increases from 20 to 64 Hz. Based upon the optical emission spectra of CO, OH, H and O species, chemluminescence spectra of CO and O recombination and CO production rate detected online by gas chromatographs, the reaction mechanism at low and high H2/CO2 molar ratios is disclosed.

Tumor hypoxia is the necessary process in the development of solid tumors, which is the key factor for drug resistance, recurrence, attack and shift of tumor. Hypoxic tumor cells have a certain extent of tolerance to radiation and chemotherapy. Tumor hypoxia is an important target for medication therapy. In the recent years, the bioreductive drugs targeted tumor hypoxia has made great process in the treatment of tumors. The latest advances of bioreductive drugs targeted hypoxia were reviewed in this paper.