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The spatial distribution of eddy diffusivity, basic characteristics of coherent mesoscale eddies and their relationship are analyzed from numerical model outputs in the Southern Ocean. Mesoscale fluctuation information is obtained by a temporal-spatial filtering method, and the eddy diffusivity is calculated using a linear regression analysis between isoneutral thickness flux and large-scale isoneutral thickness gradient. The eddy diffusivity is on the order of O (103 m2/s) with a significant spatial variation, and it is larger in the area with strong coherent mesoscale eddy activity. The mesoscale eddies are mainly located in the upper ocean layer, with the average intensity no larger than 0.2. The mean radius of the coherent mesoscale cyclonic (anticyclonic) eddy gradually decays from (121.2±10.4) km ((117.8±9.6) km) at 30°S to (43.9±5.3) km ((44.7±4.9) km) at 65°S. Their vertical penetration depths (lifespans) are deeper (longer) between the northern side of the Subpolar Antarctic Front and 48°S. The normalized eddy diffusivity and coherent mesoscale eddy activity show a significant positive correlation, indicating that coherent mesoscale eddy plays an important role in eddy diffusivity. [ABSTRACT FROM AUTHOR]

Walnut blight (WB), caused by the bacterium Xanthomonas arboricola pv. juglandis,continues to be a serious disease of walnut in northern China, where weather conditions favor disease development. From 2013 to 2017, WB incidences in walnut cv. 'Liaoning 1' were investigated in three areas (Dalian,Suizhong and Jianchang areas) in the Liaoning province, northeastern China. WB incidence was high in Dalian (23.72%) and Suizhong (24.31%) but was low in Jianchang (12.98%). Relative humidity is a key meteorological factor that affected the differences between areas. Ten walnut cultivars were surveyed in 2013, 2015, and 2017 for their susceptibility to blight. Lateral-bearing walnut cultivars showed a higher incidence and were found more susceptible to WB compared with terminal-bearing cultivars. In order to test the most effective chemical spray methods, bactericide screening trials were conducted comprising 12 different types of bactericides and mixtures in 2015. The combination of kasugamycin+mancozeb was most effective in controlling WB incidence resulting in lowest fruit disease incidence (2.63%). Subsequently, minimal spray trials were studied to determine the most effective chemical control as well as timing and frequency of application in 2017. The study confirmed these results of studies done in California: the best timing for the first spray application was at 30%–40% pistillate flower emergence and subsequently spray times were at 6 days and 16 days interval. Results of this study provide essential information to better understand the complexity of this walnut disease toward developing effective control management strategies globally. [ABSTRACT FROM AUTHOR]

"FeO"-SiO2-MgO-Al2O3-"Cr2O3" system has wide applications in characterization of the reactions between copper smelting slag and magnesia-chrome refractory and nickel laterite smelting slags. High-temperature experiments have been carried out on this system under metallic iron saturation. Liquidus temperatures and complex solid solutions have been determined by quenching and electron probe X-ray microanalysis technique. A pseudo-ternary section "FeO"-SiO2-MgO at fixed Al2O3 and "Cr2O3" has been constructed from the experimental data. Olivine 2(Mg,Fe)O·SiO2 and pyroxene (Mg,Fe)O·SiO2 are the major primary phases in the composition range investigated. The solid solutions of the olivine and pyroxene phases have been discussed. The FactSage predictions are compared with the experimental results. The present study provides accurate data for direct applications of high-temperature processing of materials and optimization of the thermodynamic modeling. [ABSTRACT FROM AUTHOR]

Tungsten leaching residues are industrial wastes that are largely generated during commercial tungsten production. The residues have been classified as hazardous solid wastes due to the presence of toxic elements. On the other hand, the residues contain valuable elements, such as W, Mn, and Fe which can be recovered for economic benefit. To utilize the residue, a carbothermic reduction process was studied to achieve the effective utilization of the residue and sustainable development of the tungsten industry. Fe-W-Mn alloys and nontoxic slags were obtained successfully at 1450°C, and can be used to produce wear-resisting iron materials and glass–ceramics, respectively. The more effective metal–slag separation was achieved by controlling the MnO concentration of the slag, which impacted the liquidus temperature and the viscosity of the slag. This study confirmed a method for utilizing the tungsten residues, which could be a step toward practical industrial-scale techniques. [ABSTRACT FROM AUTHOR]

Tungsten slag contains valuable elements, such as Bi, W, Fe, Nb, and Mn, and harmful elements, such as Pb. Here, the carbothermic reduction of tungsten slag was analyzed thermodynamically using FactSage thermochemical software and verified experimentally. CaO, SiO2, and Al2O3 could not react with C and were the major constituents of the slag. WO3, Fe2O3, Nb2O5, and MnO2 were reduced and collected in the alloy, and Bi2O3 and PbO were reduced and formed Bi and Pb, respectively, which volatilized and collected in the fumes. Increased temperature and decreased reductant addition contributed to an increase in the recovery of Nb, while the recovery of W was less affected. At reduction conditions of 14–16% reductant addition and 1500–1600°C, the recovery percentage of W, Fe, and Nb were over 90%, the recovery percentage of Mn was over 50%, and Bi and Pb were collected in the fumes. [ABSTRACT FROM AUTHOR]

In this study, the phase transformations of steelmaking slags were identified for the purpose of phosphorus separation and material recycling, where the samples after high-temperature experiments and quenching were characterized using electron probe x-ray microanalysis and x-ray diffraction. For hot slags held under argon atmosphere, the main phases changed from (Fe,Mg)O, (Fe,Ca)O and C2S-C3P (Ca2SiO4-Ca3P2O8) at 1450–1400°C to (Fe,Mg,Ca)O, C2S-C3P and CaO-TiO2-FeO-Al2O3 liquid at 1200–600°C. From the respect of phosphorus concentration in C2S-C3P, 1400°C was an optimum temperature, which also accounted for a suitable treatment temperature for cooled slags. Moreover, air atmosphere resulted in more liquid phase, CaO-MgO-Fe2O3-SiO2, due to the oxidation of Fe2+ to Fe3+. In addition to C2S-C3P, P2O5 was also present in this liquid phase, a drawback for further phosphorus recovery. The P2O5 concentration in the liquid phase decreased with decreasing temperature, and thus, a relatively lower temperature was preferred in air. [ABSTRACT FROM AUTHOR]