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In this study, the metabolism of a hydrometallurgical process for tungsten extracting from wolframite was studied through substance flow analysis. The mass balance accounts, substance flow charts of tungsten and arsenic were established to evaluate the metabolism efficiency of the investigated system. The results showed that, the total tungsten resource efficiency of the system was 97.56%, and the tungsten recovery of unit process autoclaved alkali leaching, ion exchange, Mo removing, concentration and crystallization was 98.16%, 98.94%, 99.71%, 99.89%, respectively. Meanwhile, for extracting 1 ton of tungsten into the qualified ammonium paratungstate, 10.0414 kg of arsenic was carried into the system, with the generation of 7.2801 kg of arsenic in alkali leaching residue, 1.5067 kg of tungsten in arsenic waste residue, and 1.2312 kg of tungsten in Mo residue. Besides, 7.9 g of arsenic was discharged into nature environment with waste water, 15.5g of arsenic was entrained into the final APT. The distribution and transformation behaviors of arsenic during production were analyzed through phases change analysis, and some recommendations for improving the resource efficiency of tungsten and pollution control during production were also proposed based on the substance flow analysis in this study.

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emerged as a serious threat to human health worldwide. The inactivation of SARS-CoV-2 on object surfaces and in the indoor air might help to halt the COVID-19 pandemic. Far-ultraviolet light (UVC) disinfection has been proven to be highly effective against viruses and bacteria. To understand the wavelength and duration of UVC radiation required for SARS-CoV-2 inactivation, we examined the efficacy of UVC light prototype devices with the wavelengths of 275, 254, and 222 nm. The disinfection effectiveness was determined by cell-based assays including the median tissue culture infectious dose (TCID50) and an immunofluorescent assay on African green monkey kidney epithelial Vero E6 cells. Among the three prototypes, the UVC LED (275 nm) had the best virucidal activity with a log-reduction value (LRV) &gt, 6 after 10 s of exposure. The mercury lamp (254 nm) reached similar virucidal activity after 20 s of exposure. However, the excimer lamp (222 nm) showed limited anti-SARS-CoV-2 activity with a LRV &lt, 2 after 40 s of exposure. Overall, in comparison, the UVC LED (275 nm) exhibited superior SARS-CoV-2 disinfection activity than the mercury lamp (254 nm) and the excimer lamp (222 nm).

Exogenous application of either salicylic acid (SA) or calcium chloride (CaCl2) to alleviate heat stress has been extensively studied. However, the effects of combined SA and CaCl2 treatment on the heat tolerance of poinsettia have been poorly studied. This study investigated the role of a foliar spray comprising SA and CaCl2 in managing heat tolerance of three poinsettia (Euphorbia pulcherrima Willd.) cultivars, Noel, Winter Rose (WR), and Ice Punch’ (IP). Plants were pretreated with SA, CaCl2, or combined SA and CaCl2 and then exposed to a temperature of 42 °C for 1 hour. Changes in the relative injury (RI) percentage, malondialdehyde (MDA) content, and antioxidant enzyme activities were determined. All plants were then placed in an environment-controlled greenhouse for 14 days and evaluated. Lateral bud sprouting (%), new leaf numbers, and phenotypic appearance were recorded. Results revealed that the three poinsettia cultivars varied in their appearance, morphological growth patterns, and ability to tolerate high-temperature stress. Plant growth of ‘Noel’ was more robust than that of ‘WR’ and ‘IP’, which were considerably affected by heat stress, resulting in brown, withered leaves and defoliation. In general, the effects of the combined application of SA and CaCl2 on heat-tolerant ‘Noel’ were superior to those of individual applications and no treatment (for control groups) in terms of the RI percentage, lateral bud sprouting (%), and appearance under heat stress. Application of combined SA and CaCl2 for ‘Noel’ plants was more beneficial for enhancing catalase activity and resulted in the effective alleviation of decreased malondialdehyde content under heat stress. Treatment including 200 μΜ SA and 10 mm CaCl2 may alleviate heat stress and may prove useful in breeding programs focused on improving poinsettia cultivars.

The effect of 27 MHz radio-frequency (27 RF), 915 MHz microwave (915 MW), and 2450 MHz microwave (2450 MW) on drying of barley chewable tablets was examined experimentally. It was observed that the dielectric constant was decreased with the moisture content reduction. Penetration depths of samples treated with 27 RF were the highest. The quality of products was evaluated according to color, temperature, ferric-reducing power, and DPPH scavenging. 2450 MW played a positive role in improving antioxidant properties. The comprehensive view is that radio-frequency technology may be a promising drying method for food processing.