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Abstract Listeria monocytogenes is an important foodborne pathogen known for causing listeriosis. To gain insights into the pathogenicity, genetic characterization, and evolution of various Listeria species, in vitro cell adhesion and invasion ability assays and whole-genome sequencing were performed using four Listeria strains isolated from livestock and poultry slaughterhouses. The four Listeria strains exhibited adhesion and invasion abilities in Caco-2 and RAW264.7 cells. Pathogenic Liv1-1 and Lm2-20 had higher adhesion ability, but non-pathogenic Lin4-99 was more invasive than Lm2-20 (p

Pathogen contamination is a severe problem in maintaining food safety in the cold chain. Cold plasma (CP) is a novel non-thermal disinfection method that can be applied for the bacterial inactivation of food in appropriate contexts. Currently, research on CP used on food at cold chain temperatures is rare. This work investigated the bacterial inactivation effect of CP on beef at typical cold storage temperatures of 4 and −18 °C and room temperature (25 °C). The reactive species in CP were indirectly tested by evaluating O3, NO3− and NO2− in cold plasma-activated water (PAW), which indicated the highest concentrations of reactive species in CP at 25 °C and the lowest at −18 °C. The bactericidal efficacy of CP treatment against beef inoculated with Escherichia coli at −18 °C, 4 °C, and 25 °C was 30.5%, 60.1%, and 59.5%, respectively. The 4 °C environment was the most appropriate treatment for CP against beef, with the highest bactericidal efficacy and a minor influence on beef quality. The indirect CP treatment had no significant effect on the texture, color, pH, or cooking loss of beef at −18 °C. CP shows significant potential for the efficient decontamination of food at cold chain temperatures.

Abstract In order to deal with the global energy crisis and environmental problems, reducing carbon dioxide through artificial photosynthesis has become a hot topic. Lead halide perovskite is attracted people's attention because of its excellent photoelectric properties, but the toxicity and long‐term instability prompt people to search for new photocatalysts. Herein, a series of inorganic double perovskites Cs4Mn1‐xCuxSb2Cl12 microcrystals (x = 0, 0.1, 0.2, 0.3, 0.4, and 0.5) are synthesized and characterized. Among them, Cs4Mn0.7Cu0.3Sb2Cl12 microcrystals have the best photocatalytic performance, and the yields of CO and CH4 are 503.86 and 68.35 µmol g−1, respectively, after 3 h irradiation, which are the highest among pure phase perovskites reported so far. In addition, in situ Fourier transform infrared (FT‐IR) spectroscopy and electron spin resonance (ESR) spectroscopy are used to explore the mechanism of the photocatalytic reaction. The results highlight the potential of this class of materials for photocatalytic reduction reactions.

This study analyses some characteristics of ancient construction and clarifies how they used renewable energy in their homes. This article analyzes ancient houses that were nature-oriented and used renewable energy. This study focuses on the structural system of ancient houses in Sistan. It dissects the structural elements of the old homes. The autopsy of the ancient house structure of Sistan shows the reader the techniques used in ancient architecture to provide energy. The research methods of this article are to examine the energy supply experiences of houses in the form of a case study of an old Sistan house to discover their energy-supplying techniques. This article uses the techniques used in Sistani houses with the application of modern house-building technologies, to develop a nature-oriented model. In fact, the model presented in this article is a modernized version of the ancient house of Sistan. This model gives a house completely friendly to nature and the environment and knowledge-oriented. The model contributes to housing programs addressing new requirements. Our proposed housing model and its general principles are replicable in other regions globally to use green energy sustainably.

Abstract Lead‐free halide double perovskites (DPs) have attracted great attention due to their stability, nontoxicity, and good photophysical properties. Herein, environmentally friendly small‐bandgap Cs2CuSbCl6 and Cs4CuSb2Cl12 DPs microcrystals (MCs) are prepared via a solvent synthesis technique. This study also reports a bottom‐up synthetic protocol for obtaining evenly distributed Cs2CuSbCl6 and Cs4CuSb2Cl12 quantum dots (QDs) utilizing a modified hot injection approach. These MCs and QDs have strong absorption throughout the visible region, indicating that they could be promising light‐absorbing materials as sunlight‐driven photocatalysts. For the first time, the efficient sunlight‐driven photocatalytic CO2 reduction activity of these Pb‐free “green” MCs and QDs has been revealed, and a product yield of 307 μmol g−1 and an electron consumption of 1053 μmol g−1 are achieved by the Cs4CuSb2Cl12 QDs under 3 h irradiation. Our results highlight the potential of this family of materials for photocatalytic applications.

Summary: Lead halide perovskites are prospective candidates for CO2 photoconversion. Herein, we report copper-doped lead-free Cs2AgSbCl6 double perovskite microcrystals (MCs) for gas-solid phase photocatalytic CO2 reduction. The 0.2Cu@Cs2AgSbCl6 double perovskite MCs display unprecedented CO2 photoreduction capability with CO and CH4 yields of 412 and 128 μmol g−1, respectively. The ultrafast transient absorption spectroscopy reveals the enhanced separation of photoexcited carriers in copper-doped Cs2AgSbCl6 MCs. The active sites and reaction intermediates on the surface of the doped Cs2AgSbCl6 are dynamically monitored and precisely unraveled based on the in-situ Fourier transform infrared spectroscopy investigation. In combination with density functional theory calculations, it is revealed that the copper-doped Cs2AgSbCl6 MCs facilitate sturdy CO2 adsorption and activation and strikingly enhance the photocatalytic performance. This work offers an in-depth interpretation of the photocatalytic mechanism of Cs2AgSbCl6 doped with copper, which may provide guidance for future design of high-performance photocatalysts for solar fuel production.

The solid-state core of a heat pipe cooled reactor operates at high temperatures over 1000 K with thermal and irradiation-induced expansion during burnup. The expansion changes the gap thickness between the solid components and the material properties, and may even cause the gap closure, which then significantly influences the thermal and mechanical characteristics of the reactor core. This study developed an irradiation behavior model for HPRTRAN, a heat pipe reactor system analysis code, to introduce the irradiation effects such as swelling and creep. The megawatt heat pipe reactor MegaPower was chosen as an application case. The coupled irradiation-thermal-mechanical model was developed to simulate the irradiation effects on the heat transfer and stresses of the whole reactor core. The results show that the irradiation deformation effect is significant, with the irradiation-induced strains up to 2.82% for fuel and 0.30% for monolith at the end of the reactor lifetime. The peak temperatures during the lifetime are 1027.3K for the fuel and 956.2K for monolith. The gap closure enhances the heat transfer but caused high stresses exceeding the yield strength in the monolith.

This study experimentally investigates the condensation performance of moist air on the processed windshield surface. The quantitative results of heat transfer coefficient and condensation rate of three kinds of surfaces under different working conditions are obtained. Under dry conditions, the convective heat transfer coefficients (CHTCs) of the hydrophobic and hydrophilic surfaces are about 20% and 3% higher than that of normal surface. Under wet conditions, the CHTC of hydrophobic surface is superior to that of normal surface by approximately 10%, while the CHTC of hydrophilic surface is inferior to that of normal surface by about 5%. The mean of mass transfer coefficient (kas) for the hydrophobic, hydrophilic and normal surfaces are calculated about 0.0063 m/s, 0.0054 m/s and 0.0054 m/s, respectively. The condensation rate of the hydrophobic surface is higher than that of hydrophilic one about 7–9% due to the dropwise condensation.

Listeria monocytogenes (LM) is one of the four major foodborne bacteria that cause bacteremia and meningitis. To explore the control of listeriosis with natural phages, we used the double-layer agar plate method to isolate LM from slaughterhouse sewage and designated LP8. The result of electron microscopy indicated that the phage belonged to the family of Myoviridae. Whole-genome sequencing indicated that the genome size of LP8 is 87,038 bp and contains 120 genes. Mice were infected with LM and treated with penicillin G sodium, LP8, and the combination of these two. From the levels of lymphocyte subsets (CD4+, CD8+), the expression of cytokines (TNF-α, IL1β, IL-10, and IFN-γ), observation of pathological changes in organs (heart, liver, spleen, kidney, and brain), and the bacterial load of the spleen, we concluded the therapeutic effect of LP8 against listeriosis and demonstrate the feasibility of a combined therapy to reduce the use of antibiotics. This provides a new avenue for the treatment of listeriosis.

The college building is a large energy consumer with a high density of energy consumption. However, less attention is paid to college buildings, particularly college dormitory buildings. Based on the one-year historical data collected from 20 college dormitory buildings located in Wuhan, China, this study aims to propose a three-stage strategy to identify and analyze the energy consumption patterns and characteristics of college dormitories in detail, including determining energy consumption patterns, analyzing key characteristics based on four indexes, and examining three influencing factors (occupants’ gender and floor and orientation location of rooms). The results show that the heavy energy users (around 10% of all occupants) consume around 20% of the total energy and have the narrowest comfort temperature range. However, the light energy users, 42% of total occupants, consume only approximately 27% of total energy. Their different tolerance to coldness is the main reason contributing to different energy consumption. The dormitories of males and location of the top floor and corner tend to consume significantly more energy in hot weather. This study would help campus facilities to understand the energy use behavior of occupants and formulate adequate policies so as to improve the energy management of campuses.

Loop thermosyphon with multiple evaporators has unique startup features and interaction characteristics between evaporators which are worth studying. In this paper, the startup influencing factors of a loop thermosyphon with multiple evaporators are studied experimentally and visually. Meanwhile, the interaction between evaporators is evaluated quantitatively using a newly defined parameter called interaction ratio, which represents percentage change in temperature divided by percentage change in heating power. The results show that the temperature of evaporators often has a local peak value during the startup, at which moment the boiling becomes fully developed. Also, the effect of filling ratio, heating power value and distribution on the local peak temperature is analyzed. For each evaporator, interaction ratio on itself is always the largest. Among the evaporators, interaction ratios of the evaporator in the middle are the largest because the competition and crowding of its flow with the other evaporators are more intense. With the increase of filling ratio, interaction ratios on itself decrease while interaction ratios on the others increase.

Foot steel pipe was the main arch foot supporting structure to control large deformation of loess tunnels, but the supporting effect was not ideal. Taking Yulinzi Tunnel in Qingyang, Gansu Province, as the engineering background, the design concept and implementation scheme of a foot steel pipe active bearing was put forward. The purpose was to solve the problem that it was difficult to control the surrounding rock settlement with the foot steel pipe. Numerical simulation and field experiments were used to verify the effect of the active bearing technology of the foot steel pipe. The main conclusions were as follows: (1) The effect of increasing the diameter of the foot steel pipe is better than that of increasing the number of foot steel pipes. (2) The active bearing mode of exerting its bearing capacity in advance by prepressing the foot steel pipe can effectively reduce the settlement of the vault. The settlement rate of the vault can be reduced by about 70% in 1–2 days and more than 50% in 1–3 days. (3) At the initial stage of surrounding rock deformation, this technology can provide a large bearing capacity, thereby reducing the overall deformation of the surrounding rock, slowing down the release of the surrounding rock pressure, and playing a positive role in the settlement control of the vault.

Feet-lock steel pipes have been widely applied in soft-rock tunnels, but their installation quantity and parameters depend on engineering experience. In this study, by simplifying the force between the feet-lock steel pipe and the primary lining, the load-deformation characteristics were analyzed separately, and inconsistent deformation was revealed. Next, combined with the passive and active bearing scheme, a design optimization method for feet-lock steel pipes was proposed under two working conditions, including the predicted large deformation and observed large deformation before the primary lining construction. Finally, the design method was applied to the Yulinzi Tunnel, and the results show that the original design of the feet-lock steel pipes could not meet the requirements of the controlling settlement. After the optimized design, both the passive bearing scheme installing two ϕ108 × 3-millimeter steel pipes and the active bearing scheme installing one ϕ108 × 4-millimeter steel pipe could meet the requirements of the controlling settlement. The active bearing design can significantly reduce the amount of steel required and the engineering cost. The scientificity and feasibility of the design optimization method were proven by the on-site monitoring and measurement.