Insecta is the biggest group of animals on earth. The insects are thought to be one of the biggest biological resources that have not been fully exploited by humans. China is one of the earliest countries to exploit insect resources in the world and has been the top producer for over one thousand years of many insect‐related industrial products, such as silk, insect wax and Chinese gallnuts. The exploitation and industrialization of insect resources in China is generally classified into four different levels. The first level is the direct utilization of insect bodies and their secretions, the history of which can be traced back for thousands of years. This level includes the culture and utilization of the silkworm Bombyx mori, the Chinese honeybee Apis cerana cerana, the Chinese white‐wax scale Ericerus pela, the Chinese gall aphid Schlechtendalia chinensis, and the lac insects Kerria spp. Additionally, numerous other insects are typically used for Chinese traditional medicines and food, such as Eupolyphaga sinensis, Opisthoplatia orientalis, Aspongopus chinensis, Martianus dermestoides, Polyrhachis vicina, Hepialus spp, Vespa, Hydrillodes repugnalis, and Tenebrio molitor. Pollinators (Megachile rotundata, Osmia cornifrons, O. excavata) and ornamental insects like butterflies, katydids Gampsocleis grafiosa, and fighting crickets Scapsipedes micado are also among the insects included in this level. Accordingly, a related industry is insect‐breeding, including sericulture and apiculture, which lays the basis for all insect industrialization. The second level is the utilization of insects as enemies of pests and insect pathogens for biological control. The enemy insects, including the egg parasites tricogramma Trichogramma spp, the seven spotted lady beetle Coccinella septempunctata, the Chinese green lacewing Chrysopa sinica, and Anastatus sp. could be produced in large scale. The insect pathogens that have been extensively used for commercial biocontrol in China include Helicoverpa armigera Nucleopolyhedrovirus (HaSNPV), Ectropis oblique Nucleopolyhedrovirus (EcobNPV), Spodoptera exigua multicapsid nucleopolyhedrovirus (SeMNPV), Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV), Plutella xylostella Granulosis (PxGV), Pieris rapae granulosis (PiraGV), and Bacillus thuringiensis (Bt). Related industries include the biopesticide industry and the enemy insect production industry. The third level of utilization is the extraction and synthesis of insect materials with diverse bioactivities. Some insect pheromones and hormones extracted from insect bodies or chemically synthesized have been used for insect pest control and for regulating the silkworm breeding. Toxins from honeybees and wasps have been used in medicine. Some insect materials from the larvae of honeybees, silkworms, tasar silkworms, and houseflies have been developed into health products. The fourth level is using the insects as bioreactors to produce peptides for medical and veterinary uses. Hundreds of foreign genes have been succ...

Calcium sulfoaluminate cement (CSA) is a type of low-CO2 binder which has been widely applied in the production of concrete. To investigate the protection capability offered by CSA to keep steel from corrosion, the pore solution chemistry of CSA on steel passivation was investigated in this study. The pore solution of CSA pastes, extracted by an ex situ leaching method, was studied and compared with ordinary Portland cement (OPC). The results show that the alkalinity of the CSA pore solution is not only much lower than that of OPC, but also that a new type of ion, Al(OH)4−, and high concentration of SO42− were detected in the liquid phase of CSA. Based on pore solution chemistry analysis, a simulated pore solution (SPS) system was designed to assess the comprehensive impact of alkalinity and ion composition, featured as properties of CSA, on steel passivation. The results of the corrosion potential evolution highlight the importance of alkalinity in passivation. SO42− can cause depassivation when there is not enough hydroxyl, but Al(OH)4− is able to maintain the alkalinity of the system, enhancing the stability of the passive film.

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The enhancement of the durability of sulfoaluminate cement (CSA) in marine environments is of great importance. To this end, an investigation was carried out involving the placement of CSA concrete in the tidal zone of Zhairuoshan Island, Zhoushan, China, and subjected to a 20-month marine tidal exposure test. The comparison was made with ordinary Portland cement (OPC) concrete to evaluate the effectiveness of the former. The test findings indicate that the compressive strength of both types of concrete is reduced by seawater dry-wet cycling, and the porosity of the surface concrete is increased. However, the compressive strength of CSA concrete is observed to be more stable under long-term drying–wetting cycles. When the ettringite in the CSA surface concrete is decomposed due to carbonization and alkalinity reduction, its products will react with Ca2+ and SO42− in seawater to regenerate ettringite to fill in the concrete pores, making the concrete strength more stable and hindering chlorine penetration. Furthermore, CSA concrete exhibits a higher capillary absorption capacity than OPC concrete, which results in chloride accumulation on its surface. However, the diffusion capacity of chloride in CSA concrete is significantly lower than that in OPC concrete.

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