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BaFe 2 O 4 (BF) is a promising oxygen carrier (OC) for chemical looping gasification (CLG), but its stability is low due to serious sintering. The novelty of this work is to investigate the potential of adding different supports (Al 2 O 3 , MgAl 2 O 4 , and ZrO 2) with BF to enhance performance and stability in the CLG of biochar. The results demonstrated that the addition of the supports had enhanced sintering resistance, surface area, pore properties, and oxygen vacancies on the surface simultaneously with positive effects on CLG performance. Among all supports, MgAl 2 O 4 with 50% content displayed the greatest syngas yield (0.088 mol/g) and carbon conversion (80.76%), attributed to the highest surface area and total pore volume, as confirmed by BET results. Moreover, despite the slight decline in the reactivity due to ash deposition, the BF/MgAl 2 O 4 showed stable CLG performance during the multiple cycles, which can be ascribed to the resistance of sintering provided by MgAl 2 O 4. • BaFe 2 O 4 (BF) supported by Al 2 O 3 , ZrO 2 , and MgAl 2 O 4 were prepared for CLG of biochar. • The addition of different supports showed a positive effect on CLG performance. • Sintering resistance, surface area, and oxygen vacancies were enhanced with supports. • BF/MgAl 2 O 4 exhibited highest syngas yield due to greatest surface area properties. • Despite a slight decline due to ash, BF/MgAl 2 O 4 had a stable performance during cycles. [ABSTRACT FROM AUTHOR]

AbstractDuring the drilling process, the hydration and expansion of shale are one of the main reasons for wellbore instability, which can lead to stuck drilling and economic losses. A novel shale inhibitor (ADG) was successfully synthesized by thermal polymerization using Acrylamide (AM), Dimethyl diallyl ammonium chloride (DMDAAC) and Graphene as raw materials, Ammonium persulfate, and Sodium bisulfite as initiators. In order to study the structural characteristics of ADG, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Thermogravimetric loss test (TG), and Scanning electron microscopy (SEM) test were conducted. Simultaneously, linear swelling test, mud making test, sedimentation test, contact angle test, and montmorillonite (MMT) impregnation test were conducted to evaluate its inhibitory performance. ADG can reduce the expansion height of bentonite test blocks from 6.4 mm to 2.06 mm. After adding ADG, the settling speed can be effectively accelerated, with a settling time of only 15 min and a settling height as low as 60 mm. SEM analysis revealed that ADG had a regular flake-like structure. Compared to conventional shale inhibitors, ADG can increase the contact angle of bentonite test blocks from 26.8° to 46.8°, improving their hydrophobicity. Mechanistic studies suggested that ADG molecules could adsorb on the shale surface and block surface pores, reducing the contact area between shale and water. Additionally, small ADG molecules could penetrate the pore interiors and form hydrophobic films. The dual mechanism of ADG, inhibiting hydration and providing physical blockage, further demonstrated its excellent inhibitory performance. [ABSTRACT FROM AUTHOR]

Due to the periodic switching operation of IGBT, there is a complex and high-intensity electromagnetic environment around the flexible DC converter valve. During this process, strong transit magnetic field caused by the turning on and off of large current can produce induced voltage on the nearby PCBs and even may affect the normal function of the PCBs. In this paper, the induced voltage in the output port on a PCB caused by a pulsed magnetic field is measured in laboratory. The effectiveness of a shielding box on suppressing the induced voltage and the magnetic field is also investigated experimentally. The results show that the induced voltage is about 12mV (in peak to peak value) for a 1.5kA/m, 6.4μs pulse magnetic field, and the shielding box has about 50dB time-domain shielding effectiveness.

The golden–needle mushroom Flammulina filiformis is one of the most precious cultivated edible fungi in the world. Despite recent progress in the study of F. filiformis, there is still a gap in the regulation of the mitochondrial genome during browning, which poses a serious threat to the golden–needle mushroom industry. Comparative transcriptome analysis of two isonuclear alloplasmic strains showed that changes in the mitochondrial genome lead to different gene expression and key biological pathways at different stages in the two isonuclear alloplasmic strains. Furthermore, transcriptome analysis revealed that the mitochondrial genome has a significant role in the regulation of a multitude of critical metabolic pathways relating to the browning of F. filiformis fruiting bodies. Functional enrichment analysis showed that the differentially expressed genes were mainly involved in many vital processes of mitochondria, mitochondrial membrane, and multiple amino acid metabolisms of F. filiformis. Taken together, the current study highlights the crucial role of the mitochondrial genome in the growth of F. filiformis and could be beneficial to genetic breeding of elite varieties of edible fungi. [ABSTRACT FROM AUTHOR]