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Concerning the emissions of hydrogen cyanide (HCN) and other N-bearing air pollutants from the fluid catalytic cracking (FCC) regeneration units, this paper has conducted a comprehensive testing and surface characterisation of four industrial spent catalysts, aged catalysts and hard coke sample in three different schemes, Ar-TPD, O 2 -TPO and rapid heating to elaborate the transformation of N upon the influence of the heterogeneity of coke and N speciation. In the Ar-TPD scheme, the surface N is responsive for the emission of gaseous NH 3 from pyrrolic N-5 and HCN from both pyridinic N-6 and quaternary N-Q. The removal of soft coke is beneficial in promoting the surface exposure of hard coke, thereby increasing the HCN emission dramatically. In the O 2 -TPO scheme, the oxygen accessibility is the principal factor governing the emission of HCN. The external soft coke is able to access the bulk O 2 firstly, the combustion of which in turn provides heat back to promote the cracking of internal hard coke from the same and neighbouring particles to release more HCN. The induction effect of bulk O 2 is also superior over the spent catalyst properties in formulating a nearly identical trend of HCN emission for all the four spent catalysts tested. Finally, for the use of rapid heating scheme that is typical in a commercial FCC regenerator, it is effective in accelerating the volatilisation of soft coke quickly, thereby promoting the oxygen accessibility to hard coke and the internal N-bearing precursors so as to mitigate the emission of HCN effectively. The use of a large superficial velocity of gas is further effective in sweeping the volatiles including HCN away from the catalyst, promoting their oxidation extent accordingly., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Interactions between energetic material relevant nanoscale metal oxides (SiO 2 , TiO 2 , MgO, Al 2 O 3 , CuO, Bi 2 O 3 ) and poly(vinylidene fluoride) (PVDF) at high temperature were investigated by temperature-jump/time-of-flight mass spectrometry (T-jump/TOFMS) and thermogravimetric-differential scanning calorimetry (TGA-DSC). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the morphology of the compositions, while X-ray diffraction (XRD) was utilized to analyze the condensed phase crystalline species at temperatures of interest. The exergonicity and exothermicity of HF gas with hydroxyl-terminated metal oxide surfaces make HF the likely fluorine-bearing moiety and primary mode of the fluorinating reactions, where terminal OH - configurations are replaced by F - in the formation of a stronger metal-fluorine bond. However, not all compositions produce corresponding stable metal fluoride. The results show that while some of the investigated metal oxide-PVDF compositions enhance PVDF decomposition and release HF in larger quantities than PVDF, others release HF in smaller quantities than PVDF and even retard PVDF decomposition. The former compositions demonstrate exothermic, multistep mass loss modes prior to neat PVDF mass loss, and the relative intensity of HF gas increases as the temperature of the release point decreases, implying a correlation between HF release and the progression of exothermic behavior. An interplay dynamic where surface interactions both lower the onset of HF release and engage exothermically with HF gas subsequently is proposed.

When hot forging 7075 aluminum alloy, as a military material durable enough for most of its applications, it needs to be heat-treated to ensure the target material property achieves the application requirements. However, the material properties change because of heat throughout usage. In this study, a new approach was devised to heat treat the alloy to prevent material property changes. The study further clarified the effect of rapid heat treatment on the high-temperature resistance of a hot forging 7075 aluminum alloy. Infrared (IR) heat treatment was used as a rapid heating technique to effectively replace the conventional resistance heat (RH) treatment method. Our experimental result showed that IR heat treatment resulted in better age hardening at the initial aging stage, where its tensile strength and elongation appeared like that of a resistance heat treatment. More so, based on hardness and tensile test results, the IR-heated treatment process inhibited the phase transformation of precipitations at a higher temperature, improving high-temperature softening resistance and enhancing the thermal stability of the hot forging 7075 aluminum alloy.

The invasive brown marmorated stink bug, Halyomorpha halys , is causing economic and ecological damage in invaded areas. Its overwintering behavior warrants mitigation practices in warehouses and shipping operations. The aim of this study was to characterize the mortality response curves of H. halys adults to short high-temperature exposure. Here we compared field-collected individuals entering (ENA) and exiting diapause (EXA). EXA adults displayed increased susceptibility to high temperatures compared to ENA individuals. Complete mortality of all tested individuals was obtained after 10 min exposure at 50.0 °C, and after 15 (EXA) or 20 min (ENA) at 47.5 °C. The nutritional status of these insects had no effect on high-temperature tolerance. The mortality curves obtained here may be used for the definition of cost-effective heat treatments aimed at the H. halys control.

Thermal nanoimprint lithography is playing a vital role in fabricating micro/nanostructures on polymer materials by the advantages of low cost, high throughput, and high resolution. However, a typical thermal nanoimprint process usually takes tens of minutes due to the relatively low heating and cooling rate in the thermal imprint cycle. In this study, we developed an induction heating apparatus for the thermal imprint with a mold made of ferromagnetic material, nickel. By applying an external high-frequency alternating magnetic field, heat was generated by the eddy currents and magnetic hysteresis losses of the ferromagnetic nickel mold at high speed. Once the external alternating magnetic field was cut off, the system would cool down fast owe to the small thermal capacity of the nickel mold; thus, providing a high heating and cooling rate for the thermal nanoimprint process. In this paper, nanostructures were successfully replicated onto polymer sheets with the scale of 4-inch diameter within 5 min.

Fast charging is a key enabler of mainstream adoption of electric vehicles (EVs). None of today's EVs can withstand fast charging in cold or even cool temperatures due to the risk of lithium plating. Efforts to enable fast charging are hampered by the trade-off nature of a lithium-ion battery: Improving low-temperature fast charging capability usually comes with sacrificing cell durability. Here, we present a controllable cell structure to break this trade-off and enable lithium plating-free (LPF) fast charging. Further, the LPF cell gives rise to a unified charging practice independent of ambient temperature, offering a platform for the development of battery materials without temperature restrictions. We demonstrate a 9.5 Ah 170 Wh/kg LPF cell that can be charged to 80% state of charge in 15 min even at -50 °C (beyond cell operation limit). Further, the LPF cell sustains 4,500 cycles of 3.5-C charging in 0 °C with <20% capacity loss, which is a 90× boost of life compared with a baseline conventional cell, and equivalent to >12 y and >280,000 miles of EV lifetime under this extreme usage condition, i.e., 3.5-C or 15-min fast charging at freezing temperatures., Competing Interests: The authors declare no conflict of interest.

Micro process engineering as a process synthesis and intensification tool enables an ultra-short thermal treatment of foods within milliseconds (ms) using very high surface-area-to-volume ratios. The innovative application of ultra-short pasteurization and sterilization at high temperatures, but with holding times within the range of ms would allow the preservation of liquid foods with higher qualities, thereby avoiding many unwanted reactions with different temperature-time characteristics. Process challenges, such as fouling, clogging, and potential temperature gradients during such conditions need to be assessed on a case by case basis and optimized accordingly. Owing to the modularity, flexibility, and continuous operation of micro process engineering, thermal processes from the lab to the pilot and industrial scales can be more effectively upscaled. A case study on thermal inactivation demonstrated the feasibility of transferring lab results to the pilot scale. It was shown that micro process engineering applications in thermal food treatment may be relevant to both research and industrial operations. Scaling of micro structured devices is made possible through the use of numbering-up approaches; however, reduced investment costs and a hygienic design must be assured.