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The composition inside a comet nuclear can be detected through the molecular rotational emission lines at millimeter or submillimeter wavelengths. We observed a long-period comet C/2022 E3 (ZTF) using the Purple Mountain Observatory 13.7 m radio telescope at 3.4 mm during mid January and early February in 2023. From the observed spectra, the hydrogen cyanide (HCN)( J = 1–0) spectra lines was detected. The mean production rate of HCN is (8.30 ± 1.14) × 10 ^25 molec. ​s ^−1 in mid January and (3.91 ± 0.84) × 10 ^25 molec. ​​​s ^−1 in early February. we also estimated the upper limit of the production rate of HCO+. We obtained the abundance of HCN relative to water, (0.13 ± 0.02)% in mid January when C/2022 E3 (ZTF) got close to the Sun at 1.11 au, and (0.13 ± 0.03)% in early February at 1.16 au. Our conclusion leans toward E3 being similar to most comets, with the abundance of HCN remaining stable during our two observation periods.

In order to make full use of jujube resources and further explore the processing and utilization value of jujube fruit, the changes of jujube nutrition, color and quality indexes after natural drying, hot air drying and vacuum freeze-drying in different harvesting stages were compared and analyzed using mu-jujube fruit as the test material. The results showed that the contents of VC, crude fiber, flavonoids and triterpenoids of white ripe dates were higher than those of semi-red dates, and those of semi-red dates were higher than those of all-red dates under the same drying methods. The contents of soluble sugars and polysaccharides of white ripe dates were significantly (P0.05). The original color, quality and texture of jujube were kept by vacuum freeze drying, while the flesh of white ripe period and half red stage jujube turned green to red, and the color difference and hardness increased after natural drying and hot air drying, which were close to or even higher than that of full red stage jujube. It could be concluded that the early harvested white and semi-red jujube fruit had better processing characteristics, and vacuum freeze-drying was the best drying method for high-value drying process. The results would provide a theoretical basis for early harvesting and processing of jujube fruit.

We performed secular monitoring broadband photometric observations on Jupiter Family Comets (JFCs) 68P/Klemola and 78P/Gehrels 2 from 2018 November to 2020 March with the Yaoan High Precision Telescope. Our main purpose is to study the dust activity, coma properties, and dynamical history of the two comets and analyze the activity evolution of 78P/Gehrels 2 in the recent past. We use aperture photometry to obtain the magnitude and the A (0) f ρ values from the R band observations. The maximum A (0) f ρ values we recorded for 68P/Klemola and 78P/Gehrels 2 are 339.7 ± 4.4 cm and 1028.1 ± 13.3 cm, respectively, showing that the activity of 68P/Klemola is of middle level while 78P/Gehrels 2 is one of the most active JFCs. The mean color of 78P/Gehrels 2 is ( B − V ) = 0.88 ± 0.02 and ( V − R ) = 0.27 ± 0.02. Dynamical history analysis suggests that 78P/Gehrels 2 could have actually resided in this region for a long time in the past 1 Myr, though it recently migrated into the inner solar system. The high activity of 78P/Gehrels 2 reported in the past three perihelion passages could be attributed to the perihelion distance decl. from 2.3 to 2.0 au before 1997 that boosted the water-ice sublimation rate and formed new active regions. The activity decl. over recent apparitions could be attributed to the reformation of the dust mantle.

Comet 60P/Tsuchinshan is a Jupiter family comet. Since the discovery of 60P/Tsuchinshan, little research for cometary activity has been conducted on this comet, though it has returned to perihelion several times. To study the physical properties and activity characteristic of 60P/Tsuchinshan during its 2018–2019 apparition, we observed 60P/Tsuchinshan with broadband B , V , and R filters from 2018 November to 2019 March by using the 80 cm Yaoan High Precision Telescope at Yaoan Station of Purple Mountain Observatory, Chinese Academy of Sciences. Morphological analysis and photometric studies of 60P/Tsuchinshan were performed. The color indices, Af ρ values, and dust production rates of 60P/Tsuchinshan were obtained. Morphological analysis showed that the comet was active and several images showed a spiral structure in the inner coma; this structure is regardless of the enhancement methods and cannot be explained by the rotation of 60P. The Af ρ curve showed that the peak activity of 60P/Tsuchinshan was at about 10 days after perihelion. Compared to other Jupiter family comets at similar heliocentric distances, we found that 60P/Tsuchinshan was a very active comet. Dynamical analysis showed that 60P/Tsuchinshan’s perihelion distance was reduced from 1.77 to 1.62 au due to the close encounter with Jupiter that occurred on 2008 December 20; this may increase its activity in the next apparition.

Salmonella infection is an important foodborne consumer health concern that can be mitigated during food processing. Bacteriophage therapy imparts many advantages over conventional chemical preservatives including pathogen specificity, natural derivation, potency, and providing a high degree of safety. The objective of this study aimed to isolate and characterize a phage that effectively control Salmonella food contamination. Out of 35 isolated phages, LPSE1 demonstrated a broad Salmonella host range, robust lytic ability, extensive pH tolerance, and prolonged thermal stability. The capacity for phage LPSE1 to control Salmonella Enteritidis-ATCC13076 in milk, sausage, and lettuce was established. Incubation of LPSE1 at 28°C in milk reduced recoverable Salmonella by approximately 1.44 log10 CFU/mL and 2.37 log10 CFU/mL at MOI of 1 and 100, respectively, as relative to the phage-excluded control. Upon administration of LPSE1 at an MOI of 1 in sausage, Salmonella count decreased 0.52 log10 at 28°C. At MOI of 100, the count decreased 0.49 log10 at 4°C. Incubation of LPSE1 on lettuce reduced recoverable Salmonella by 2.02 log10, 1.71 log10, and 1.45 log10 CFU/mL at an MOI of 1, 10, and 100, respectively, as relative to the negative control. Taken together, these findings establish LPSE1 as an effective weapon against human pathogenic Salmonella in various ready to eat foods.