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It is well known that salt-gypsum evaporites play a significant role in controlling the physio-mechanical performance of the earth's upper mantle as well as forming extensive “halokineticˮ structures that are directly linked to lithologic hydrocarbon reservoirs and petroleum accumulation. Under many geological conditions, hot saline groundwater frequently intrudes into salt-gypsum evaporite sequences. However, relatively little is known regarding the micromechanical behaviour of salt-gypsum in these saline environments, and this behaviour governs the macro-mechanical behaviour and the overall deformation. In this study, we examine the microstructural evolution of salt-gypsum and its weakening mechanisms under varied brine conditions (or coupled thermal-hydrological-chemical environments). A series of laboratory tests, including scanning electron microscopy and micro-computed tomography (MCT), were conducted to study how the petrographic characteristics, including porosity, pore size distribution and fractal dimension, evolved. In total, 81 specimens were prepared and then soaked in brines of 3 different concentrations and at 3 different temperatures. The results showed the following: 1) after brine treatment, the MCT slices of the specimens generally contained four areas: a residual porous skeleton area, an undissolved area, a cracked area and an interface area. 2) For a given concentration, the porosity and fractal dimensions of the specimens gradually increased with temperature, while for a given temperature, the porosity and fractal dimension tended to decrease as the brine concentration increased. 3) Because the nucleation or initiation rate of new voids was slower than the growth and coalescence rate of the original voids, the proportion of 0–1 μm pores gradually decreased over time. However, the proportion of 5 to + ∞ μm pores gradually increased over time. To study the effects of each factor and the interactions between them on the response variables (porosity and fractal dimension), 2 × 2 and 2 × 3 factorial designs were employed to assess the brine concentrations and temperatures. The results verify that the water temperature significantly weakened the salt-gypsum, while the chlorine ions had a much weaker effect.

The Li-ion battery is becoming the optimal choice for the Electric Vehicle’s (EV) power supply. In order to protect the Li-ion battery from charging damage and to prolong the battery’s life, a special control strategy based on the dynamic balanced point along with a non-dissipative equalizer is presented. The main focus of the proposed control strategy is to insure that the individual cell of a battery pack will be rapidly, efficiently and simultaneously balanced, by adjusting equalizing current of each cell dynamically. In this paper, a model of a four series connected Li-ion batteries pack has been established to evaluate the proposed control strategy. Superior performance is demonstrated by the simulation and experiment.

Islanding detection is a necessary function for grid connected distributed generators. Islanding detection methods can be classified as two catalogues: remote detecting methods and local detecting methods. Most of them have limitation and defects when they are applied in photovoltaic power stations. Recently Synchronous measurement is proposed to be applied for islanding detecting. Although the islanding detection method is supposed to be applied in traditional bulk power systems, it is also suitable for renewable generation power plants. To do this islanding detection will be implemented on central management unit of photovoltaic power station instead of on grid-tied inverters as traditionally. In implementing, the criteria of this method and the threshold of algorithm are to be optimized. This paper develops a test device to validate the proposed islanding detection method applying in PV station, and provide a platform for the algorithm optimization.

To evaluate the therapeutic effect of hematopoietic stem cell transplantation (HSCT), we performed HSCT in 30 patients with hematologic maligancies. Of the 30 patients, 10 underwent autologous peripheral blood stem cell transplantation (auto-PBSCT), 13 underwent myeloablative allogeneic HSCT while 7 underwent nonmyeloablative allogeneic HSCT, which were designated as autologous group, myeloablative group and nonmyeloablative group, respectively. All patients except the one who underwent cord blood transplantation, were successfully engrafted. Median time for the granulocytesor = 0.5 x 10(9)/L and plateletsor = 20 x 10(9)/L were 12 days and 13 days respectively in autologous group, 16 days and 19 days in myeloablative group, 15 days and 12 days in nonmyeloablative group. In myeloablative group, acute graft-versus-host diseases (aGVHD) was observed in 3 patients, all of which were I-II grade. Oral mucous cGVHD was observed in 1 patient. In nonmyeloablative group, 1 patient developed intestinal aGVHD grade IV and cutaneous cGVHD was induced by donor lymphocyte infusions (DLI) in 3 patients. 1 patient had hematological relapse in autologous group. 1 patient had cytogenetic relapse in myeloablative group. In nonmyeloablative group 3 patients had cytogenetic relapse and were cured by DLI, 1 patient had hematological relapse. 4 of the 30 patients died of infection (2 patients), grade IV aGVHD (1) and relapse (1) respectively. 26 patients are still alive. 3 years overall survival (OS) and 3 years disease free survival (DFS) were 100% and 64.81% respectively in autologous group, 78.75% and 63% respectively in myeloablative group while both 66.67% in nonmyeloablative group. In conclusion, autologous group had less transplant-related complications and mortality. Active prophylaxis of relapse could significantly promote DFS. The transplant-related mortality limited DFS in myeloablative group. More relapses occurred in nonmyeloablative group, but could be cured by DLI.