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BACKGROUND: Fruit flies are important economic pests of fruits, vegetables, and nuts all over the world. In this study, a permanent ecological trap, which was created by the ovicidal effect of phytogenic hydrogen cyanide (HCN) liberated from passion fruits due to oviposition by fruit flies and can be used in the pest management, were determined. RESULTS: Observation of fruit fly eggs in Passiflora within the passion fruit cultivation region in southern China, from Aug 2019 to Oct 2020 showed that the exotic Passiflora attracted the native fruit flies to oviposit, but the eggs could not hatch. Using classical staging to categorize embryonic development and fumigation assays, we show that oviposition by fruit fly on passion fruits, release HCN from the cyanogenic mesocarp. Exposure of the eggs to HCN causes arrest of embryonic development and finally the death of eggs. CONCLUSION: Our results reveal that the life cycle of fruit fly in Passiflora is interrupted at the egg stage. Consequently, we predict that this ecological trap may be permanent. Extensive cultivation of the Passiflora vine as a dead‐end trap crop may be an effective avenue to reduce populations of fruit fly pests. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Abstract: Rapid pyrolysis of three typical Chinese coals, lignite from Inner Mongolia, bituminous from Shenfu coalfield, and anthracite from Guizhou, as well as a petroleum coke were carried out in a drop-style high-frequency furnace. The reactor was induction coil heated and had a very small high-temperature zone, which could restrain secondary conversions of nitrogen products. The effects of temperature and coal rank on conversions of fuel-N to primary nitrogen products (char-N, HCN–N, NH3–N and (tar+N2)–N) have been investigated. The results showed that, the increasing temperature reduced the yields of char-N and promoted the conversion of fuel-N to N2. Char-N yields increased, while volatile-N yields decreased as the coal rank increased. In most of the conditions, NH3–N yields were higher than HCN–N yields during rapid pyrolysis of coal. In the case of petroleum coke, NH3–N yields increased gradually with the increasing temperature, but no HCN was detected. We argue that NH3–N can be formed directly through the primary pyrolysis without secondary reactions. Although volatile-N yields of lignite were higher than those of bituminous, yields of (HCN+NH3)–N in volatile-N of lignite were lower than those of bituminous. While the (HCN+NH3)–N yields of anthracite were the lowest of the three coals. Both of the (HCN+NH3)–N yields and (HCN+NH3)–N proportions in volatile-N of petroleum coke were lower than the three coals. [Copyright &y& Elsevier]

A sewage sludge sample from a wastewater treatment plant in China was pyrolysed in a fluidised-bed/fixed-bed reactor and in a fluidised-bed/tubular reactor. HCN was found to be the main NOx precursor, representing up to about 80% of the nitrogen present in the sludge. The thermal cracking of volatiles is the main route of HCN formation. NH3 was also an important NOx precursor formed during the pyrolysis of the sewage sludge. The experimental results indicate that there are at least two distinctive stages of NH3 formation during the pyrolysis of the sewage sludge at a fast heating rate. The formation of NH3 at temperatures lower than 400–500 °C is at least partly due to the amino structures in the sludge. The reactions of volatiles in the gas phase make negligible contributions to the observed NH3 yield. [Copyright &y& Elsevier]