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The time evolution of dielectric barrier discharge driven by nanosecond pulse high-voltage power is investigated by high-speed video analysis, electrical measurements and spectral diagnostics. It is found that the discharge mode generally goes through the evolution process of filamentary discharge → diffuse discharge → filamentary discharge with the increase in discharge cycle. The time-dependent changes in the standard deviation of image gray levels indicate that the discharge uniformity first improves and then deteriorates in this evolution process. The different pre-ionization density and modulated distribution of space charges and surface charges are considered to be the main reasons for the time evolution of discharge uniformity. In addition, the experiments under different frequencies and voltages show that the transition of the discharge mode is more likely to occur at higher frequency and higher voltage. Further measurement and calculation reveal that the discharge at high frequency and high voltage has the same characteristics, that is, high pre-ionization degree, thick filament diameter and short time lag. These characteristics usually lead to higher seed electron density, larger critical avalanche size and weaker lateral inhibition effect, which make the discharge mode transition more likely to occur. [ABSTRACT FROM AUTHOR]

The solubilities in the quaternary system K+, NH4+//Cl−, SO42--H2O and its two ternary subsystems NH4Cl-KCl-H2O, (NH4)2SO4-K2SO4-H2O at 80.0 °C were measured using the isothermal dissolution equilibrium method under atmospheric pressure, and the corresponding phase diagrams were plotted. In the phase diagram of the NH4Cl-KCl-H2O system, there are three crystalline zones, which correspond to (K1−m,(NH4)m)Cl, ((NH4)n,K1−n)Cl and the co-existence zone of (K1−m,(NH4)m)Cl and ((NH4)n,K1−n)Cl, respectively. In the phase diagram of the (NH4)2SO4-K2SO4-H2O system, there is only one crystalline zone for (K1−t,(NH4)t)2SO4. In the phase diagram of the K+, NH4+//Cl−, SO42--H2O system, there are three crystal zones, which correspond to (K1−t,(NH4)t)2SO4, (K1−m,(NH4)m)Cl and ((NH4)n,K1−n)Cl, respectively. According to the analysis and the calculations for the phase diagrams of the K+, NH4+//Cl−, SO42--H2O system at 80.0 °C and 50.0 °C, this paper proposes a technological process. In the process, the (K1−t,(NH4)t)2SO4 can be prepared at 80.0 °C and the ((NH4)n,K1−n)Cl can crystallize out at 50.0 °C. The mass fraction of K2SO4 in product L1 (K1−t,(NH4)t)2SO4 (t = 0.1465) is 88.48%. The composition of solid solutions in the K+, NH4+//Cl−, SO42--H2O system was experimentally determined and then theoretical calculations about the process can be carried out. [ABSTRACT FROM AUTHOR]

Highlights: [•] Determination of phase equilibrium of Na2SO4–MgSO4–(NH4)2SO4–H2O system at 25°C. [•] Phase diagram of this system was investigated and analyzed. [•] A new technology to produce Mg–N compound fertilizers was proposed. [•] The advantage of recycling mother liquid, steady production and energy saving. [ABSTRACT FROM AUTHOR]

Thesolubilities of the ternary system MgSO4–(NH4)2SO4–H2O and thequaternary system Na2SO4–MgSO4–(NH4)2SO4–H2O at 0 °C were measured, and the phase diagrams of these twosystems wereplotted. On the basis of the phase diagrams obtained, we analyzedeach saturation point and crystalline region. It indicated thatammonium sulfate as the salting-out agent can form double salt MgSO4·(NH4)2SO4·6H2O with magnesium sulfate, realizing better separation of sodiumsulfate and magnesium sulfate. On the basis of the Pitzer model ofelectrolyte solution theory, the ionic strength function was introducedto express the interaction parameters between two kinds of electrolyteat 0 °C. The interaction parameters were regressed from the experimentaldata of the ternary systems, and the solubilities of Na2SO4–MgSO4–(NH4)2SO4–H2O system at 0 °C werecalculated. The results showed that the calculated values werewell consistent with experimental results. [ABSTRACT FROM AUTHOR]

Hepatic stellate cells (HSCs) are considered as the main effector cells in vitamin A metabolism and liver fibrosis, as well as in hepatic immune regulation. Recently, researches have revealed that HSCs have plasticity and heterogeneity, which depend on their lobular location and whether liver is normal or injured. This research aimed to explore the biological characteristics and heterogeneity of HSCs in mice with Schistosoma japonicum ( S. japonicum ) infection, and determine the subpopulation of HSCs in pathogenesis of hepatic fibrosis caused by S. japonicum infection. Results revealed that HSCs significantly increased the expressions of MHC II and fibrogenic genes after S. japonicum infection, and could be classified into MHC II + HSCs and MHC II − HSCs subsets. Both two HSCs populations suppressed the proliferation of activated CD4 + T cells, whereas only MHC II − HSCs displayed a myofibroblast-like phenotype. In response to IFN-γ, HSCs up-regulated the expressions of MHC II and CIITA , while down-regulated the expression of fibrogenic gene Col1 . In addition, praziquantel treatment decreased the expressions of fibrogenic genes in MHC II − HSCs. These results confirmed that HSCs from S. japonicum -infected mice have heterogeneity. The MHC II − α-SMA + HSCs were major subsets of HSCs contributing to liver fibrosis and could be considered as a potential target of praziquantel anti-fibrosis treatment. [ABSTRACT FROM AUTHOR]