Continuous cold rubidium atomic beam with enhanced flux and tunable velocity.

We present a cold atomic beam source based on a two-dimensional (2D)+ magneto-optical trap (MOT), capable of generating a continuous cold beam of 87Rb atoms with a flux up to 4.3 × 109 s-1, a mean velocity of 10.96(2.20) m/s, and a transverse temperature of 16.90(1.56) µK. Investigating the influence of high cooling laser intensity, we observe a significant population loss of atoms to hyperfine-level dark states. To account for this, we employ a multiple hyperfine level model to calculate the cooling efficiency associated with the population in dark states, subsequently modifying the scattering force. Simulations of beam flux at different cooling and repumping laser intensities using the modified scattering force are in agreement with experimental results. Optimizing repumping and cooling intensities enhances the flux by 50%. The influence of phase modulation on both the pushing and cooling lasers is experimentally studied, revealing that the mean velocity of cold atoms can be tuned from 9.5 m/s to 14.6 m/s with a phase-modulated pushing laser. The versatility of this continuous beam source, featuring high flux, controlled velocity, and narrow transverse temperature, renders it valuable for applications in atom interferometers and clocks, ultimately enhancing bandwidth, sensitivity, and signal contrast in these devices.

Regional population and social welfare from the perspective of sustainability: Evaluation indicator, level measurement, and interaction mechanism.

Key to regional sustainable development are the development and interplay of population dynamics and social welfare, each playing a significant role. As a representative region with demographic characteristics such as negative population growth and large labor outflow, the development and interaction between population and social welfare in Nanchong deserve in-depth exploration. This article takes the development of population and social welfare in Nanchong as the research object, and constructs an evaluation indicator system of population and social welfare through research backtracking, and uses entropy method and coupling coordination model to measure the development level and interactive effect of population and social welfare in Nanchong from 2010 to 2021. The research results show that: Firstly, the comprehensive evaluation results of population in Nanchong shows a linear upward trend, which indicates the stable positive effect of population structure and distribution, the gradual improvement effect of population quality effectively compensate for the weakening effect of population quantity, thus achieving the positive development of population. Secondly, the comprehensive evaluation results of social welfare in Nanchong shows an exponential upward trend, which indicates the social welfare has maintained a rapid growth momentum in various dimensions and the long-term positive effects have completely absorbed the negative effects, thus achieving the positive development of social welfare. Thirdly, during the sample period, the population and social welfare in Nanchong consistently maintained a high level of interaction strength, with factors diffusing and integrating. On this basis, the diffusion theory is used as an empirical reference to construct three interactive mechanisms between the population and social welfare in Nanchong and the implications are inferred from the empirical results.

Enhancing sodium percarbonate catalytic wet peroxide oxidation with artificial intelligence-optimized swirl flow: Ni single atom sites on carbon nanotubes for improved reactivity and silicon resistance.

H2O2 is widely used in the treatment of refractory organic pollutants.However, due to its explosive and corrosive chemical characteristics, H2O2 will bring great safety risks and troubles in transportation.So we chose sodium percarbonate(SPC) to be used in catalytic wet peroxide oxidation enhanced by swirl flow(SF-CWPO) and we designed carbon nanotubes with Ni single atom sites(Ni-NCNTs/AC) to activate SPC to treat an m-cresol wastewater containing Si.Meanwhile, artificial intelligence which used Artificial neural network (ANN) was used to optimize the conditions.Under the conditions of pH = 9.27, reaction time of 8.91 min, m-cresol concentration is 59.09 mg L-1, SPC dosage is 2.80 g L-1 and Na2SiO3·9H2O dosage is 77.27 mg L-1, the degradation rate of total organic carbon(TOC) and m-cresol reaches 94.37% and 100%, respectively.Finally, the applicability of Ni-NCNTs/AC-SPC-SF-CWPO technology was evaluated in a wastewater system of a sewage treatment enterprise and Fourier transform ion cyclotron resonance mass spectrum(FT-ICR MS) analysis and chemical oxygen demand(COD) analysis showed the great ability of Ni-NCNTs/AC-SPC-SF-CWPO technology to treat wastewater.It is believed that this paper is of great significance to the design and construction of the in-depth research and industrial application of SF-CWPO.

Analysis of the degradation of m-cresol with Fe/AC in catalytic wet peroxide oxidation enhanced by swirl flow.

Catalytic wet peroxide oxidation (CWPO) enhanced by swirl flow (SF-CWPO) was developed for the first time to explore the degradation of m-cresol in 3%iron/activated carbon catalysed Fenton reaction. Under the conditions of catalyst dosage of 0.6 g/L, H2O2 dosage of 1.5 mL/L, pH = 6 and reaction time of 20 min, the degradation rate of m-cresol and total organic carbon in 100 mg/L m-cresol solution reaches 81.5% and 82%, respectively. The reaction speed in the SF-CWPO system with an independently designed cyclone reactor was two times faster than the traditional CWPO systems. In addition, via liquid chromatography-mass spectrometry analysis of the degradation product, the possible degradation pathway for m-cresol was proposed. The proposed SF-CWPO can potentially be an efficient and economical method to treat organic pollutants in wastewaters.

Oxygen-vacancy-mediated LaFe1-xMnxO3-δ perovskite nanocatalysts for degradation of organic pollutants through enhanced surface ozone adsorption and metal doping effects.

Here, a series of LaFe1-xMnxO3-δ perovskite nanocatalysts were synthesized and tested for the catalytic ozonation of m-cresol for the first time. The B-site cation is regulated by metal doping, and the resulting LaFe0.26Mn0.74O3-δ with a rhombohedral structure showed excellent catalytic performance and structural stability owing to the abundant oxygen vacancies and the higher Fe2+/Fe3+ and Mn3+/Mn4+ ratios. Theoretical calculations have revealed that the oxygen vacancy has a strong affinity for ozone adsorption, and thus facilitated ozone decomposition by extending the O-O bond. Combined with low-valence Fe2+ and Mn3+ cations, the electron transfer in the catalytic ozonation reaction has been enhanced, which has promoted the production of reactive oxygen species (ROS). Taken together, the degradation pathway of m-cresol was proposed. Additionally, the LaFe0.26Mn0.74O3-δ catalyst remained stable during a 60 h reaction. This study has not only revealed the adsorption/decomposition pathways of ozone using LaFe0.26Mn0.74O3-δ perovskite nanocatalysts but also provided indepth insight into the electron transfer pathway on the surface of nanocatalysts during the process of catalytic ozonation.

Pyrolyzed carbon derived from red soil as an efficient catalyst for cephalexin removal.

Red soil, a typical soil type in southern China, has been deemed infertile or nutrient-deficient. In this study, red soil was firstly utilized as a substrate for preparing catalysts, which were then successfully applied to the catalytic wet peroxide oxidation (CWPO) of cephalexin. The highest cephalexin removal was 95.23% and TOC removal was 60.58%, with the catalyst pyrolyzed at 500 °C (RC500). The high iron content and proportion of Fe(II) on the surface of RC500 was responsible for the decomposition of H2O2 into· OH. Moreover, the porous structure and existence of other minerals (such as SiO2 and Al2O3) in the catalyst were also significant for enhancing the catalytic activity of RC500. Afterwards, the influencing parameters, including temperature, pH, the dose of H2O2, and catalyst, were examined for cephalexin degradation. It was noteworthy that RC500 was efficient in treating hospital wastewater when using a self-design pilot device. A density functional theory analysis of cephalexin was conducted to establish the possible position attacked by ·OH, and the possibly ruptured one. Meanwhile, the intermediates generated during CWPO were identified. Finally, a reliable degradation pathway of cephalexin was proposed on the basis of the results.

Feature Channel Expansion and Background Suppression as the Enhancement for Infrared Pedestrian Detection.

Pedestrian detection is an important task in many intelligent systems, particularly driver assistance systems. Recent studies on pedestrian detection in infrared (IR) imagery have employed data-driven approaches. However, two problems in deep learning-based detection are the implicit performance and time-consuming training. In this paper, a novel channel expansion technique based on feature fusion is proposed to enhance the IR imagery and accelerate the training process. Besides, a novel background suppression method is proposed to stimulate the attention principle of human vision and shrink the region of detection. A precise fusion algorithm is designed to combine the information from different visual saliency maps in order to reduce the effect of truncation and miss detection. Four different experiments are performed from various perspectives in order to gauge the efficiency of our approach. The experimental results show that the Mean Average Precisions (mAPs) of four different datasets have been increased by 5.22% on average. The results prove that background suppression and suitable feature expansion will accelerate the training process and enhance the performance of IR image-based deep learning models.

Dataset for NiO/ZnO biomorphic nanocomposite using a poplar tree leaf template to generate an enhanced gas sensing platform to detect n-butanol.

The SEM image data presented in this article was collected by the Scanning electron microscopy (SEM) performed on an XL-30 ESEM FEG scanning electron microscopy. The diameter stastics data was collected and calculated by the Image-Pro Plus software system. The UV-Vis Res spectrum was collected by solid state UV diffuse reflector Shimadzu UV-4100 at wavelength 200-800 nm. The SEM image data showed more details of the poplar tree leave template(PTLT). The diameter stastics data show the diameter averagely distributed in the material. The UV-Vis Res spectrum reflected the physical property of PTLT NiO/ZnO. Interpretation of this data can be found in a research article titled "One-step facile synthesis of a NiO/ZnO biomorphic nanocomposite using a poplar tree leaf template to generate an enhanced gas sensing platform to detect n-butanol" (Qingrui Zeng et al., 2019) [1], Research Article DOI: 10.1016/j.jallcom.2019.05.018•The SEM image provide the more details about the distinction of the PTLT ZnO and conventional ZnO, further present more morphology information of the PTLT biotemplate. Exhibiting a facile and green way for synthesising ZnO and narrow down the size of ZnO crystal, present the advantage of PTLT ZnO in morphology control. Motivating gas sensor researcher to fabricate ZnO by a biotemplate method, which owned biomorphic and extraordinary gas sensing properties.•The UV-Vis Res spectrum present more detail of the energy band information of PTLT ZnO and PTLT NiO/ZnO, which is use for the gas sensing mechanism analysis. Inspiring researcher forcus on the construction on p-n heterojunction type gas sensor to enhance the gas sensing properties.•The material researchers work on the morphic investigation, gas sensor, and application of semiconductor.•These data are benefit for the application of biotemplate method for material fabrication and material application.

Effect of cold plasma on maintaining the quality of chub mackerel (Scomber japonicus): biochemical and sensory attributes.

BACKGROUND: Atmospheric cold plasma (ACP) has emerged as a potential alternative to traditional methods for non-thermal food decontamination. However, few data are available about ACP treatment for seafood. In this study, dielectric barrier discharge (DBD) was applied to generate CP, and the aim of the study was to investigate the effectiveness of DBD-ACP on improving the quality of chub mackerel on the basis of chemical, microbial and sensory characteristics. RESULTS: The effect of DBD-ACP on the quality of chub mackerel (Scomber japonicus) during storage was examined. Results revealed that the optimal voltage level and exposure time of this treatment were 60 kV and 60 s respectively, and such conditions exhibited excellent inactivation efficacy and weak influence on proximate chemical compositions. Variations in total viable count (TVC), sensory scores and total volatile basic nitrogen (TVB-N) indicated that ACP treatment extended the shelf life of chub mackerel to 14 days, whereas samples without this treatment exceeded the limits of the three parameters after 6 days. The slow development rates of peroxide value (PV) and thiobarbituric acid (TBA) value implied that lipid oxidation was also effectively retarded by ACP exposure. Scanning electron microscopy confirmed that CP could effectively delay the degradation of myofibrillar proteins and enhance the stability of tissue structures. CONCLUSION: The excellent antimicrobial efficacy of ACP treatment makes it a potential and promising alternative to other seafood preservation technology. This is the first report on the application of ACP to seafood, which is essential to perishable food storage. © 2018 Society of Chemical Industry.