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The adherence ability of cement clinker on magnesia-spinel refractories is investigated, using a sandwich test, at 15501C for 30 min under a load of 5.3 kPa. Fractional factorial experiments determine that the silica ratio (SR)-SiO 2 /(Al 2 O 3 1-Fe 2 O 3 ) and particle size of raw meal, as well as heating rate, have a significant effect on adherence ability. Microstructural analyses indicate that the adherence ability depends upon reactions between clinker and refractories at high temperature. Only spinel reacts with CaO and 3CaO Á SiO 2 from clinker to form n-calcium aluminate (such as 3CaO Á Al 2 O 3 , 12CaO Á 7Al 2 O 3 , CaO Á Al 2 O 3 ), but there is no reaction between MgO and the clinker. Fine crystalline spinel, evenly distributed in magnesiabased brick, is prone to reacting with lime-containing phases from clinker to form low melting phases and a belite-enriched zone at the clinker/brick interface. This reaction positively contributes to the high adherence on a magnesiaÀspinel brick. The high content of liquid in clinker with low SR accelerates reactions between spinel and clinker, while a limited reaction occurs at the brick/clinker interface with high silica.

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Adherence ability of cement clinker on doloma refractories was investigated using a specially designed sandwich test conducted at 1550°C for 30 min, under a load of 5.3 kPa. Fractional factorial experiments determined that silica ratio, particle size, and alumina ratio of raw meal had significant effects on the reactions between the clinker and the refractory. Silica ratio was found to be the most prominent factor influencing the adherence strength of the clinker on the surface of doloma bricks. Doloma refractory, having an excess of free lime, reacts with clinker to form additional C3S at the interface, which is greatly beneficial to adherence strength. The interface of doloma/clinker with low silica ratio is covered with a continuous MgO‐enriched layer, which is formed from the CaO reacting with the raw meal in presence of a large amount of liquid phase generated in the clinker. This layer reduced the adherence strength of clinker on doloma. With high silica‐ratio raw meal, clinker and doloma form a C3S‐rich layer at the interface, improving strongly the adherence strength of clinker on the brick.

While it has been well characterized that chemosensory receptors in guts of mammals have great influence on food preference, much remains elusive in insects. Insect chemosensory proteins (CSPs) are soluble proteins that could deliver chemicals to olfactory and gustatory receptors. Recent studies have identified a number of CSPs expressed in midgut in Lepidoptera insects, which started to reveal their roles in chemical recognition and stimulating appetite in midgut. In this study, we examined expression patterns in midgut of 21 Spodoptera litura CSPs (SlitCSPs) characterized from a previously reported transcriptome, and three CSPs were identified to be expressed highly in midgut. The orthologous relationships between midgut expressed CSPs in S. litura and those in Bombyx mori and Plutella xylostella also suggest a conserved pattern of CSP expression in midgut. We further demonstrated that the expression of midgut-CSPs may change in response to different host plants, and SlitCSPs could bind typical chemicals from host plant in vitro. Overall, our results suggested midgut expressed SlitCSPs may have functional roles, likely contributing to specialization and adaption to different ecosystems. Better knowledge of this critical component of the chemsensation signaling pathways in midguts may improve our understanding of food preference processes in a new perspective.