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Energy-resolved neutron imaging is an effective way to investigate the internal structure and residual stress of materials. Different sample sizes have varying requirements for the detector's imaging field of view (FOV) and spatial resolution. Therefore, a dual-mode energy-resolved neutron imaging detector was developed, which mainly consisted of a neutron scintillator screen, a mirror, imaging lenses, and a time-stamping optical fast camera. This detector could operate in a large FOV mode or a high spatial resolution mode. To evaluate the performance of the detector, the neutron wavelength spectra and the multiple spatial resolution tests were conducted at CSNS. The results demonstrated that the detector accurately measured the neutron wavelength spectra selected by a bandwidth chopper. The best spatial resolution was about 20 μm in high spatial resolution mode after event reconstruction, and a FOV of 45.0 mm × 45.0 mm was obtained in large FOV mode. The feasibility was validated to change the spatial resolution and FOV by replacing the scintillator screen and adjusting the lens magnification.

In view of the electromagnetic interference existing in the well, it can greatly interfere with the voltage signal of the operational amplifier terminal collected by the dynamometer, and then affect the accuracy of the pressure value measured by the sensor. The design uses the domestic HC32L176 micro controller unit as the main control chip. Develop a dynamometer which uses the chip. Collect the voltage signal through the oscilloscope. Select the appropriate wavelet basis function, the number of decomposition layers, threshold rule and threshold function to decomposesignals containing noise. Filter out the high-frequency components of different layers,and then reconstruct the signal to obtain the denoising signal . Through Matlab simulation and practical test, the results show that the wavelet transform can achieve a good denoising of the collected voltage signal, and improve the reliability and stability of the bolt and cable dynamometer.

Reconfigurable intelligent surface (RIS) employs passive beamforming to control the wireless propagation channel, which benefits the wireless communication capacity and the received energy efficiency of wireless power transfer (WPT) systems. Such beamforming schemes are classified as discrete and non-convex integer programming problems. In this paper, we propose a Monte-Carlo (MC) based random energy passive beamforming of RIS to achieve the maximum received power of electromagnetic (EM) WPT systems. Generally, the Gibbs sampling and re-sampling methods are employed to generate phase shift vector samples. And the sample with the maximum received power is considered the optimal solution. In order to adapt to the application scenarios, we develop two types of passive beamforming algorithms based on such MC sampling methods. The first passive beamforming uses an approximation of the integer programming as the initial sample, which is calculated based on the channel information. And the second one is a purely randomized algorithm with the only total received power feedback. The proposed methods present several advantages for RIS control, e.g., fast convergence, easy implementation, robustness to the channel noise, and limited feedback requirement, and they are applicable even if the channel information is unknown. According to the simulation results, our proposed methods outperform other approximation and genetic algorithms. With our methods, the WPT system even significantly improves the power efficiency in the nonline-of-sight (NLOS) environment.

Abstract Ammonia-oxidizing archaea and bacteria (AOA and AOB, respectively) are important intermediate links in the nitrogen cycle. Apart from the AOA and AOB communities in soil, we further investigated co-occurrence patterns and microbial assembly processes subjected to inorganic and organic fertilizer treatments for over 35 years. The amoA copy numbers and AOA and AOB communities were found to be similar for the CK and organic fertilizer treatments. Inorganic fertilizers decreased the AOA gene copy numbers by 0.75–0.93-fold and increased the AOB gene copy numbers by 1.89–3.32-fold compared to those of the CK treatment. The inorganic fertilizer increased Nitrososphaera and Nitrosospira. The predominant bacteria in organic fertilizer was Nitrosomonadales. Furthermore, the inorganic fertilizer increased the complexity of the co-occurrence pattern of AOA and decreased the complexity pattern of AOB comparing with organic fertilizer. Different fertilizer had an insignificant effect on the microbial assembly process of AOA. However, great difference exists in the AOB community assembly process: deterministic process dominated in organic fertilizer treatment and stochastic processes dominated in inorganic fertilizer treatment, respectively. Redundancy analysis indicated that the soil pH, NO3 −N, and available phosphorus contents were the main factors affecting the changes in the AOA and AOB communities. Overall, this findings expanded our knowledge concerning AOA and AOB, and ammonia‐oxidizing microorganisms were more disturbed by inorganic fertilizers than organic fertilizers.

The pure corrosion, pure erosion and erosion-corrosion behaviours of X65 carbon steel in corrosive fluid and slurry of different pH were studied at low flow velocity. Results show that the corrosion pattern changed from general corrosion to pitting damage along with the occurrence of erosion in pH = 3 solution and it is postulated that this feature might be associated with changes in the cathodic reaction. The sand impacts would cause the transient of main cathodic reaction from hydrogen evolution to oxygen reduction. Density and connected small pits generated in pH = 7 solution containing sand particles. While, the increase of the solution pH from 7 to 11 resulted in more scattered and serious pitting damage, which is caused by more focused initial anodes. The occurrence of pitting damage has complicated the analysis of the electrochemical results. The sand impacts in pH = 13 solution could cause the local breakdown of passive film, leading to a significant decrease of pitting resistance.

Microbial diversity is an important indicator of soil fertility and plays an indispensable role in farmland ecosystem sustainability. The short-term effects of fertilization and rhizobium inoculation on soil microbial diversity and community structure have been explored extensively; however, few studies have evaluated their long-term effects. Here, we applied quantitative polymerase chain reaction (qPCR) and amplicon sequencing to characterize the effect of 10-year fertilizer and rhizobium inoculation on bacterial communities in soybean bulk and rhizosphere soils at the flowering–podding and maturity stages. Four treatments were examined: non-fertilization control (CK), phosphorus and potassium fertilization (PK), nitrogen and PK fertilization (PK + N), and PK fertilization and Bradyrhizobium japonicum 5821 (PK + R). Long-term co-application of rhizobium and PK promoted soybean nodule dry weight by 33.94% compared with PK + N, and increased soybean yield by average of 32.25%, 5.90%, and 5.00% compared with CK, PK, and PK + N, respectively. The pH of PK + R was significantly higher than that of PK and PK + N at the flowering–podding stage. The bacterial abundance at the flowering–podding stage was positively correlated with soybean yield, but not at the maturity stage. The significant different class Gemmatimonadetes, and the genera Gemmatimonas, and Ellin6067 in soil at the flowering–podding stage were negatively correlated with soybean yield. However, the bacterial community at class and genus levels at maturity had no significant effect on soybean yield. The key bacterial communities that determine soybean yield were concentrated in the flowering–podding stage, not at maturity stage. Rhizosphere effect, growth period, and treatment synergies resulted in significant differences in soil bacterial community composition. Soil organic matter (OM), total nitrogen (TN), pH, and available phosphorus (AP) were the main variables affecting bacterial community structure. Overall, long-term co-application of rhizobium and fertilizer not only increased soybean yield, but also altered soil bacterial community structure through niche reconstruction and microbial interaction. Rhizobium inoculation plays key role in reducing nitrogen fertilizer application and promoting sustainable agriculture practices.

In order to explore the antioxidant effect of the British red kidney bean antioxidant peptide components, ultrafiltration and dextran gel G-15 chromatography technology were used to classify the antioxidant products prepared by alkaline protease enzymatic hydrolysis of the British red kidney bean antioxidant protein, and the effect of components with higher antioxidant activity on PC12 cells damaged by H2O2 was studied. The results showed that the antioxidant peptide component BRKBAPC-2 could alleviate the cell growth inhibitory effect of H2O2 on PC12. With the increasing of peptide concentration, the level of intracellular reactive oxygen species (ROS) levels, malondialdehyde (MDA) content and lactate dehydrogenase (LDH) extracellular activity were all reduced, the activity of superoxide dismutase (SOD), catalase (CAT) and the content of reduced glutathione (GSH) were all increased, especially when the concentration of BRKBAPC-2 was 200 μg/mL, ROS level was 32.53%, MDA content was 0.96 nmol/μg prot, LDH extracellular activity was 202.12 U/L, compared with the model group, they were significantly reduced (P

Indigenous soil microbial biomass (ISMB) plays a key role in maintaining essential functions and biodiversity of soil health. One of the critical unknowns is how the indigenous microorganisms respond to different fertilizers which is directly related to agricultural production. Therefore, we used Mi-Seq sequencing and network analyses to compare the response of ISMB to biogas residue and chemical fertilizers. The results showed that crop production was profoundly influenced by levels of ISMB present and is further dependent on the strategy of fertilizer application. Higher ISMB primarily manifests through retention of richer microbial abundance, a balanced community structure, and tightened co-occurrence within a certain proportion of Nitrospirae, Rhizophlyctidaceae, and Gemmatimonadetes. Compared to chemical fertilizer, biogas residue resulted in higher production with more strongly linked nodes such as Actinobacteria, Chloroflexi and Gemmatimonadetes. Under the same level of ISMB, the microbial diversity was richer and co-occurrence was tighter when biogas residues were applied compared with chemical fertilizer. In addition, the higher level of ISMB with biogas residue applied had a lower abundance of potential fungal pathogens in both bulk and rhizosphere soil compared with chemical fertilizer. This study provides critical data to understand the influence of ISMB and biogas residue on soil ecological system.

Rhizosphere microbial communities are vital for plant growth and soil sustainability; however, the composition of rhizobacterial communities, especially the assembly process and co-occurrence pattern among microbiota after the inoculation of some beneficial bacteria, remains considerably unclear. In this study, we investigated the structure of rhizomicrobial communities, their assembly process, and interactions contrasting when Bradyrhizobium japonicum 5038 and Bacillus aryabhattai MB35-5 are co-inoculated or Bradyrhizobium japonicum 5038 mono-inoculated in black and cinnamon soils of soybean fields. The obtained results indicated that the Chao and Shannon indices were all higher in cinnamon soil than that in black soil. In black soil, the co-inoculation increased the Shannon indices of bacteria comparing with that of the mono-inoculation. In cinnamon soil, the co-inoculation decreased the Chao indices of fungi comparing with that of mono-inoculation. Compared with the mono-inoculation, the interactions of microorganisms of co-inoculation in the co-occurrence pattern increased in complexity, and the nodes and edges of co-inoculation increased by 10.94, 40.18 and 4.82, 16.91% for bacteria and fungi, respectively. The co-inoculation of Bradyrhizobium japonicum 5038 and Bacillus aryabhattai MB35-5 increased the contribution of stochastic processes comparing with Bradyrhizobium japonicum 5038 inoculation in the assembly process of soil microorganisms, and owing to the limitation of species diffusion might restrict the direction of pathogenic microorganism movement. These findings support the feasibility of rebuilding the rhizosphere microbial system via specific microbial strain inoculation and provide evidence that the co-inoculation of Bradyrhizobium japonicum 5038 and Bacillus aryabhattai MB35-5 can be adopted as an excellent compound rhizobia agent resource for the sustainable development of agriculture.

A partial pre-rusted wire beam electrode (WBE) was designed to study the influence of the rust layer on rebar corrosion in the carbonated simulated concrete pore solution (SCPS). The results show that the passive film generated on the pre-rusted steel area is more fragile than that formed on the fine polished steel area in carbonaceous media. Nevertheless, the pitting corrosion resulting from the presence of chloride ions still tends to occur on the fine polished steel surface due to the local acidification process being hindered by the rust layer. The rust layer could play a more important role than the passive film in inhibiting the initiation of chloride-induced corrosion on rebar. The expansion path of the corrosion product would be blocked by the rust layer, leading to the pit propagating in the fine polished region. Furthermore, the growth of pitting corrosion is greatly accelerated due to the catalytic cathodic reaction of the rust layer.

To solve the problem of rapid deterioration and short shelf life of fresh-cut potatoes, this experiment investigated the effect of heat treatment at 45 ℃ for 3 min combined with vacuum packaging or 30% CO2 + 70% N2 modified atmosphere packaging on the storage quality of fresh-cut potatoes. The results showed that the combination of heat treatment and modified atmosphere packaging suppressed the increase in the respiration rate of fresh-cut potatoes, significantly inhibited the increase in malondialdehyde content (MDA) as well as phenylalanine ammonia-lyase (PAL), peroxidase (POD), polyphenol oxidase (PPO) activities (P < 0.05), effectively maintained the contents of total phenol, ascorbic acid (AsA), soluble solids and starch, restrained the increase in total bacterial count, and preserved the volatile flavor and sensory quality of fresh-cut potatoes. In conclusion, heat treatment combined with modified atmosphere packaging can preserve the sensory and nutritional quality of fresh-cut potatoes, and inhibit the growth of microbes and browning enzyme activities, thereby extending the shelf life of fresh-cut potatoes.

The present study investigated the effects of cow manure ratios mixed with maize stover, rice straw, and wheat stalk at 3, 2, 1 (total solid based, TS-based), respectively, on methane production and microbial community structure during the anaerobic co-digestion process. Results showed cow manure co-digested with maize stover, wheat stalk, and rice straw at ratios of 2, 1, and 3 had the highest cumulative methane yields (272.99, 153.22 167.73 mL/g volatile solid (VS), respectively) and better stability (e.g. pH, volatile fatty acids (VFAs) and their component). The main microbe evolution had a similar trend which was Petrimonas and Methanosaeta in the early digestion process (Days 0-7) and then evolved into Longilinea, Ruminofilibacter, and Methanosarcina with the progress of digestion, but the relative abundance of these microbes in each reactor was different. It was worth noting that Caldicoprobacter in cow manure to maize stover ratio of 2, and to rice straw ratio of three reactors had a relatively higher proportion than reactor of cow manure to wheat stalk ratio of 1, and Hydrogenophaga was the specific bacterium in cow manure to wheat stalk ratio of 1 reactor. In addition, Petrimonas showed positive relationship with VFAs and Longilinea was the opposite. Methanosaeta and Methanobacterium contributed the most during the peak period of methane production in cow manure and maize stover co-digested reactor, and showed positive relationship with acetic acid. However, Methanosarcina and Methanospirillum made a great contribution during the peak period of methane production in cow manure co-digested with wheat stalk and rice straw reactors. These findings could provide further information on the application of cow manure co-digested with crop wastes. [ABSTRACT FROM AUTHOR]

Objective: To clarify the relationship between helicobacter pylori (Hp) infection, tongue manifestation and gastroscopic manifestation, and explore the mechanism of action of "oral-gastric microecology" in the occurrence and development of stomach-related diseases., Medhods: A total of 1100 patients were divided into Hp positive group and Hp negative group according to 13C breath test results. The tongue manifestation materials from patients were collected to make tongue printing slides for morphological observation of exfoliative cells from tongue coating, and electronic gastroscopy was performed on the patients and the data was analyzed., Results: Hp infection rate was about 45.95%; and the greasy coating was mostly observed in Hp positive group (63.14%, 0.05). The total tongue coating distribution was as follows: yellow greasy coating (56.66%, 0.05) > yellow coating > white coating > white greasy coating. The gastric mucosal roughness and mucosal hematoplastic plaques in the two groups were more common in the Hp positive group ( 0.05). There was a significant difference in the granular subgroup and in the rough mucosal group (< 0.05)., Conclusions: Hp infection is more commonly observed in yellow greasy coating, and this can be used as a reference for Traditional Chinese Medicine in determining whether it is Hp infection or not. Mucosal granule roughness, hyperemia, and oral Hp showed association with Hp infection in the stomach and interacted with micro-ecological environment that is composed of the oral cavity.