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Enhanced hepatic metabolic perturbation of polystyrene nanoplastics by UV irradiation-induced hydroxyl radical generation

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Journal of Environmental sciences 2024年第8期142卷 259-268页

作者： Shiyu He Jingran Wang Lihong Zhou Zhen Mao Xiaodan Zhang Jin Cai Peili Huang School of Public Health and Beijing Key Laboratory of Environmental Toxicology Capital Medical UniversityBeijing 100069China

The environmental behavior of and risks associated with nanoplastics(NPs)have attracted considerable ***,compared to pristine NPs,environmental factors such as ultraviolet(UV)irradiation that lead to changes in the toxicity of NPs have rarely been *** evaluated the changes in morphology and physicochemical properties of polystyrene(PS)NPs before and after UV irradiation,and compared their hepatotoxicity in *** results showed that UV irradiation caused particle size reduction and increased the carbonyl index(CI)and negative charge on the particle ***-aged PS NPs(aPS NPs)could induce the generation of hydroxyl radicals(·OH),but also further promoted the generation of·OH in the Fenton reaction *** pathological damage was more severe in mice exposed to aPS NPs,accompanied by a large number of vacuoles and hepatocyte balloon-like changes and more marked perturbations in blood glucose and serum lipoprotein,alanine aminotransferase and aspartate aminotransferase *** addition,exposure to PS NPs and aPS NPs,especially aPS NPs,triggered oxidative stress and significantly damaged the antioxidant capacity of mice *** with PS NPs,exposure to aPS NPs increased the number of altered metabolites in hepatic and corresponding metabolic pathways,especially glutathione *** research suggests that UV irradiation can disrupt the redox balance in organisms by promoting the production of·OH,enhancing PS NPs-induced liver damage and metabolic *** study will help us understand the health risks of NPs and to avoid underestimation of the risks of NPs in nature.

关键词： Polystyrene nanoplastics Ultraviolet-aged nanoplastics Metabolic pathway Metabolomics Hydroxyl radical

A new method for evaluating the firing precision of multiple launch rocket system based on Bayesian theory

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Defence Technology（防务技术） 2024年第2期32卷 232-241页

作者： Yunfei Miao Guoping Wang Wei Tian College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjingJiangsuChina Institute of Launch Dynamics Nanjing University of Science and TechnologyNanjingJiangsuChina

How to effectively evaluate the firing precision of weapon equipment at low cost is one of the core contents of improving the test level of weapon system.A new method to evaluate the firing precision of the MLRS considering the credibility of simulation system based on Bayesian theory is proposed in this *** of all,a comprehensive index system for the credibility of the simulation system of the firing precision of the MLRS is constructed combined with the group analytic hierarchy process.A modified method for determining the comprehensive weight of the index is established to improve the rationality of the index weight *** Bayesian posterior estimation formula of firing precision considering prior information is derived in the form of mixed prior distribution,and the rationality of prior information used in estimation model is discussed *** the simulation tests,the different evaluation methods are compared to validate the effectiveness of the proposed ***,the experimental results show that the effectiveness of estimation method for firing precision is improved by more than 25%.

关键词： Multiple launch rocket system Bayesian theory Simulation credibility Mixed prior distribution Firing precision

Metasurface-assisted low-frequency performance enhancement of ultra-broadband honeycomb absorber based on carbon nanotubes

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Nano Research 2024年第9期17卷 8542-8551页

作者： Cai-Liang Wang Shuang Bai Pei-Yan Zhao Tao Zhou Hui-Ya Wang Jun-Peng Wang Luo-Xin Wang Guang-Sheng Wang School of Chemistry Beihang UniversityBeijing 100191China Aerospace science and Industry Corporation of Wuhan Magnetoelectricity Co. Ltd.Wuhan 430070China College of Materials science and Engineering Key Laboratory for New Textile Materials and Applications of Hubei ProvinceWuhan Textile UniversityWuhan 430200China School of Chemistry and Chemical Engineering Lingnan Normal UniversityZhanjiang 524048China School of Materials science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China

Here,we present a unique method to enhance the low-frequency absorption performance of a honeycomb absorber by integrating a *** geometrical dimensions of the proposed metasurface have been numerically *** introduction of the metasurface allows exploitation of its robust resonance and superior impedance matching in low-frequency bands,thereby improving microwave absorption *** incorporation of the metasurface does not impact the wave transmission performance of the honeycomb core absorber at high-frequency band,thus preserving its high-frequency *** broadens the absorption range,leading to an expanded *** results reveal that the composite absorber(CA)exhibits strong absorption performance with an incident angle stability up to 45°for both transverse electric(TE)and transverse magnetic(TM)*** absorption mechanism of the CA has been investigated by using an equivalent circuit model and electromagnetic field analysis.A prototype was designed,fabricated,and tested to validate the proposed *** simulation and measurement results demonstrate that the prototype can achieve an average absorption rate exceeding 90%across a 1.0-18.0 GHz *** study introduces an innovative technique for creating microwave absorbers for low-frequency wideband applications.

关键词： low frequency metasurface radar absorption impedance matching

The risk factors and threshold level of subchronic inhalation exposure of reclaimed water

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Journal of Environmental sciences 2024年第3期137卷 639-650页

作者： Jiayang Kong Yun Lu Yunru Ren Menghao Chen Gang Liu Liangliang Shi State Key Joint Laboratory of Environment Simulation and Pollution Control State Environment Protection Key Laboratory of Microorganism Application and Risk ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China

Inhalation of reclaimed water is known to cause lung infammation,and free endotoxins have been shown to be a major risk factor for acute *** exposure has also been shown to induce infammatory responses with visible tissue ***,subchronic risk factors have yet to be identified,and a threshold for the protection of occupational populations during urban reuse is *** this study,potential risk factors in reclaimed water were examined by subchronic exposure with fractionated reclaimed water,and the health risk threshold was tested with a series of diluted reclaimed ***,following a 12-week exposure,macromolecules and microorganisms were found to be two major risk factors in reclaimed water that could cause pulmonary infammation,including increased proportion of polymorphonuclear leukocytes in bronchoalveolar fuid,formation of inducible bronchus-associated lymphoid tissue,and elevation of Immunoglobulin A ***,infammation persisted after a 4-week recovery *** calculated threshold of reclaimed water exposure for mice was 31.8 Endotoxin Unit(EU)/(kg·day)under when exposed to 50%additional relative humidity from reclaimed water at 25℃ for 2 hr/***,the subchronic threshold estimate for humans under the same exposure conditions was found to be 12.2 EU/(kg·day),corresponding to endotoxin levels of 61.7 EU/mL in reclaimed *** threshold level of endotoxin was lower than that in most non-potable reclaimed *** findings of this study suggest that occupational exposure of reclaimed water can serve as a potential risk to workers.

关键词： Reclaimed water Inhalation exposure Risk factor Threshold Infammation Endotoxin

Non-diffracting integer-order and half-integer-order carpet beams obtained by even-type sinusoidal amplitude radial gratings

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Chinese Optics Letters 2024年第7期22卷 86-92页

作者： Yefeng Liu Huiqing Li Rijian Chen Changjiang Fan Yile Shi Zhijun Ren Key Laboratory of Optical Information Detecting and Display Technology Zhejiang Normal UniversityJinhua 321004China

In this work,we introduce a kind of new structured radial grating,which is named the even-type sinusoidal amplitude radial(ETASR)*** on diffraction theory and the principle of stationary phase,a comprehensive theoretical investigation on the diffraction patterns of ETASR gratings is *** results show that novel carpet beams with beautiful optical structures and distinctive characteristics have been constructed on the basics of the ETASR *** diffraction patterns are independent of propagation distance,that is,the new carpet beams have diffraction-free propagating *** non-diffracting carpet beams are divided into two types by beam characteristics:non-diffracting integer-order and half-integer-order carpet ***,we experimentally generate these carpet beams using the ETASR ***,their particularly interesting optical morphology and features are explored through numerical simulations and experiments.

关键词： even-type sinusoidal amplitude radial gratings principle of stationary phase non-diffracting integer-order carpet beams non-diffracting half-integer-order carpet beams.

Experimental study of the damage characteristics of rocks containing non-penetrating cracks under cyclic loading

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International Journal of Mining science and Technology 2024年第2期34卷 197-210页

作者： Jun Xu Xiaochun Xiao Lu Ma Sen Luo Jiaxu Jin Baijian Wu School of Mechanics and Engineering Liaoning Technical UniversityFuxin 123000China School of Civil Engineering Liaoning Technical UniversityFuxin 123000China Department of Engineering Mechanics Southeast UniversityNanjing 211189China

The damage evolution process of non-penetrating cracks often causes some unexpected engineering *** specimens containing non-penetrating crack(s)are used to study the damage evolution and characteristics under cyclic *** results show that under cyclic loading,the relationship between the number of non-penetrating crack(s)and the characteristic parameters(cyclic number,peak stress,peak strain,failure stress,and failure strain)of the pre-cracked specimens can be represented by a decreasing linear *** damage evolution equation is fitted by calibrating the accumulative plastic strain for each cycle,and the damage constitutive equation is proposed by the concept of effective ***,non-penetrating cracks are more likely to cause uneven stress distribution,damage accumulation,and local failure of *** local failure can change the stress distribution and relieve the inhibition of non-penetrating crack extension and eventually cause a dramatic destruction of the ***,the evolution process caused by non-penetrating cracks can be regarded as one of the important reasons for inducing *** results are expected to improve the understanding of the process of spalling formation and rockburst and can be used to analyze the stability of rocks or rock structures.

关键词： Damage characteristics Constitutive model Fissured rocks Non-penetrating crack Cyclic loading

The action mechanism of the work done by the electric field force on moving charges to stimulate the emergence of carrier generation/recombination in a PN junction

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1001-1014页

作者： Lingyun GUO Yizhan YANG Wanli YANG Yuantai HU Department of Mechanics School of Aerospace EngineeringHubei Key Laboratory of Engineering Structural Analysis and Safety AssessmentHuazhong University of Science and TechnologyWuhan 430074China

It is discovered that the product of the current and the electric field in a PN junction should be regarded as the rate of work(power)done by the electric field force on moving charges(hole current and electron current),which was previously misinterpreted as solely a Joule heating *** clarify that it is exactly the work done by the electric field force on the moving charges to stimulate the emergence of non-equilibrium carriers,which triggers the novel physical *** regards to Joule heat,we point out that it should be calculated from Ohm’s law,rather than simply from the product of the current and the electric *** on this understanding,we conduct thorough discussion on the role of the electric field force in the process of carrier recombination and carrier *** thermal effects of carrier recombination and carrier generation followed are incorporated into the thermal equation of *** present study shows that the exothermic effect of carrier recombination leads to a temperature rise at the PN interface,while the endothermic effect of carrier generation causes a temperature reduction at the *** two opposite effects cause opposite heat flow directions in the PN junction under forward and backward bias voltages,highlighting the significance of managing device heating phenomena in design ***,this study possesses referential significance for the design and tuning on the performance of piezotronic devices.

关键词： piezoelectric semiconductor(PS) work done by electric field force thermal effect piezotronic device resistivity conductivity

Client selection and resource scheduling in reliable federated learning for UA V-assisted vehicular networks

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Chinese Journal of Aeronautics 2024年第9期37卷 328-346页

作者： Hongbo ZHAO Liwei GENG Wenquan FENG ChangmingZHOU School of Electronics and Information Engineering Beihang UniversityBeijing 100191China

Federated Learning(FL),a promising deep learning paradigm extensively deployed in Vehicular Edge Computing Networks(VECN),allows a distributed approach to train datasets of nodes locally,e.g.,for mobile vehicles,and exchanges model parameters to obtain an accurate model without raw data ***,the existence of malicious vehicular nodes as well as the inherent heterogeneity of the vehicles hinders the attainment of accurate ***,the local model training and model parameter transmission during FL exert a notable energy burden on vehicles constrained in *** view of this,we investigate FL client selection and resource management problems in FL-enabled UAV-assisted Vehicular Networks(FLVN).We first devise a novel reputation-based client selection mechanism by integrating both data quality and computation capability metrics to enlist reliable high-performance ***,to fortify the FL reliability,we adopt the consortium blockchain to oversee the reputation informa-tion,which boasts tamper-proof and interference-resistant ***,we formulate the resource scheduling problem by jointly optimizing the computation capability,the transmission power,and the number of local training rounds,aiming to minimize the cost of clients while guaranteeing *** this end,we propose a reinforcement learning algorithm employing an asynchronous parallel network structure to achieve an optimized scheduling *** results show that our proposed client selection mechanism and scheduling algorithm can realize reliable FL with an accuracy of 0.96 and consistently outperform the baselines in terms of delay and energy consumption.

关键词： Federated learning Vehicular edge computing Resource management Reinforcement learning Optimization techniques

Field-based evidence for the enrichment of intrinsic antibiotic resistome stimulated by plant-derived fertilizer in agricultural soil

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Journal of Environmental sciences 2024年第1期135卷 728-740页

作者： Shihai Liu Ziming Han Dong Zhu Xiao Luan Liujie Deng Liping Dong Min Yang Yu Zhang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China State Environmental Protection Engineering Center for Harmless Treatment and Resource Utilization of Antibiotic Residues Khorgos 835007China University of Chinese Academy of sciences Beijing 100049China

Animal manures have been demonstrated to enhance antibiotic resistance in agricultural ***,little is known about the effects of plant-derived fertilizer on soil antibiotic ***,metagenomic sequencing was used to investigate the effects of a plantderived fertilizer processed from sugarcane and beet on soil antibiotic resistance genes(ARGs)in a soybean field along crop growth *** profiles in the soils amended by plant-derived fertilizer were compared with those in the soils amended by chicken *** abundance and diversity of total ARGs in the soils amended by plant-derived fertilizer were significantly(P<0.05)elevated at the sprout stage,to a level comparable to that in the manured ***,unlike chicken manure mainly introducing manure-borne ARGs to soil,the plant-derived fertilizer was indicated to mainly enrich multidrug resistance genes in soil by nourishing indigenous *** with abundances in amended soils significantly(P<0.05)higher than in unamended soils at the sprout stage of soybean were considered as enriched *** in the abundance of the enriched ARGs was observed in both the amended soils from the sprout to the *** analysis further identified Proteobacteria and Bacteroidetes as the primary bacterial taxa involved in the temporal variation of the enriched ARGs in the soils amended by plant-derived fertilizer,while in manured soils were Firmicutes and *** revealed by multivariate statistical analyses,variation of the enriched ARGs in the soils amended by plant-derived fertilizer was majorly attributed to the response of co-occurred bacteria to depleting nutrients,which was different from the failed establishment of manure-borne bacteria in the manured *** study provided field-based evidence that plant-derived fertilizer stimulated the intrinsic antibiotic resistome,and proposed attention to the un-perceived risk since some clinically relevant ARGs originate and evolve fr

关键词： Organic fertilizer Intrinsic antibiotic resistance Indigenous bacteria Metagenomic sequencing