Acid pretreatment plays an important role in the preparation of amorphous silica with high activity and high specific surface area before combustion process. However, some limitations and problems exist in the pretreatment process of previous literatures. On the basis of this, this work is aimed at simplifying the acid pretreatment process and combustion condition, which could present a more advantageous process for practical industrial applications. Then the removal percentage and behavior of metal impurities in rice husk is studied by ICP‐OES, and effects of acid pretreatment on properties of rice husk ash (RHA) at various combustion temperatures are comprehensively investigated in comparison with previous results by scanning electron microscope (SEM), X‐ray fluorescence (XRF), X‐ray diffractometer (XRD), and surface analyzer. The results suggest that the removal degree of each metal is various due to each chemical form in rice husk, of which removal percentage of K is especially remarkable. The contributions of simplified acid pretreatment to the properties of RHA are equally prominent: smaller nanoscale particles, higher purity, and specific surface area of above 200 m2/g. In addition, the pretreatment can also eliminate the crystallization and keep the high activity of RHA in combustion temperature range of 600–900°C. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 830–837, 2017

A thorough understanding of fungal pathogen adaptations is essential for treating fungal infections. Recent studies have suggested that the role of small RNAs expressed in fungal microsporidia genomes are important for elucidating the mechanisms of fungal infections.

In this study, silicone rubber (SR) composites were prepared with various amounts of aluminum nitride (AlN) and alumina tri-hydrate (ATH), and vinyl tri-methoxysilane (VTMS) was also introduced to prepare SR/ATH/AlN–VTMS composites for comparison. Compared to the SR/ATH composites, the SR/ATH/AlN composites with higher AlN loading exhibited higher breakdown strength and thermal conductivity, which were further improved by the addition of VTMS. Such results were related to the enhanced rubber–filler interfacial interactions from VTMS coupling, as demonstrated by scanning electron microscopy (SEM) analysis and the curing behaviors of the SR composites. Moreover, by replacing ATH with VTMS-coupled AlN, the SR/ATH/AlN–VTMS composites also exhibited lower dielectric loss along with an increased dielectric constant, suggesting the promising application of VTMS-coupled AlN as a filler for the preparation of the SR composites as high-voltage insulators.

For predicting and relieving ash-related problems and harmful gas emissions during fluidized bed combustion, release of K and Cl and emissions of NO x and SO 2 during reed black liquor (BL) combustion in a fluidized bed were investigated in this study. The effects of bed material (calcium-based zeolite and limestone) and bed temperatures (700−900 °C) were also studied. The results showed that higher temperature favored the K release for both calcium-based zeolite and limestone, and calcium-based zeolite caused lower K release due to the formation of K 3 Al(SO 4 ) 3 , KAl(SO 4 ) 2 , and K 2 O-Al 2 O 3 -SiO 2 eutectic compounds. Cl was mainly released in the form of HCl above 700 °C. Moreover, high temperature facilitated Cl release for calcium-based zeolite, whereas it had a complicated effect on Cl release for limestone. Although higher temperature increased the NO x emission for both calcium-based zeolite and limestone, limestone resulted in higher NO x emission due to the conversion of fuel N to NO x under CaO catalysis. Temperature had a slight effect on SO 2 emission for calcium-based zeolite, whereas it decreased the SO 2 emission for limestone. Reed BL combustion generated lower SO 2 emissions with the help of Na 2 CO 3 and K 2 CO 3 , and limestone resulted in much lower SO 2 emission with the help of CaCO 3 and CaO.

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