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Journal of Environmental Sciences 2024年第3期137卷 321-332页

作者： Yong-li Cai Yu-hang Xu Ji-Zun Xiang Zhi-Qiang Zhang Qiu-Xiang he Ya-Feng li Jian lü Fujian Provincial Key laboratory of Soil Environmental health and Regulation College of Resources and EnvironmentFujian Agriculture and Forestry UniversityFuzhou 350002China State Key laboratory of Photocatalysis on Energy and Environment Fuzhou UniversityFuzhou 350116China

Pesticides and its degradation products,being well–known residues in soil,have recently been detected in many water bodies as pollutants of emerging concerns,and thus there is a contemporary demand to develop viable and cost–effective techniques for the removal of related organic pollutants in aqueous ***,a visible-light-responsive Fenton system was constructed with iron–doped bismuth oxybromides(Fe–BiOBr)as the *** the advantage of sustainable Fe(Ⅲ)/Fe(Ⅱ)conversion and optimized h_(2)O_(2)utilization,the optimal Fe–BiOBr–2 catalyst showed an excellent atrazine removal efficiency of 97.61%in 120 min,which is superior than the traditional homogeneous Fenton and the majority of heterogeneous processes documented in the *** this photo–Fenton system,hydroxyl(·Oh)and superoxide(·O_(2)^(-))radicals were dominant active species contributed to the oxidative degradation of *** to the production of various active radicals,five degradation pathways were proposed based on the identification of intermediates and degradation ***,this work not only demonstrates a fundamental insight into creating highly efficient and atom economic photo-Fenton systems,but also provides a complementary strategy for the treatment of organic pollutants in water.

关键词： Bismuth oxybromide Photo–Fenton Atrazine Catalytic degradation

Digital generation of super-Gaussian perfect vortex beams via wavefront shaping with globally adaptive feedback

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high Power laser Science and Engineering 2024年第1期12卷 42-51页

作者： Rui Ma Ke hai luo Jing Song he Wei li Zhang Dian Yuan Fan Anderson S.l.Gomes Jun liu International Collaborative laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education Institute of Microscale OptoelectronicsShenzhen UniversityShenzhenChina Institute for Advanced Study Shenzhen UniversityShenzhenChina Fiber Optics Research Centre School of Information and Communication EngineeringUniversity of Electronic Science and Technology of ChinaChengduChina Departamento de Física Universidade Federal de PernambucoRecife-PEBrazil

high-intensity vortex beams with tunable topological charges and low coherence are highly demanded in applications such as inertial confinement fusion(ICF) and optical communication. however, traditional optical vortices featuring nonuniform intensity distributions are dramatically restricted in application scenarios that require a high-intensity vortex beam owing to their ineffective amplification resulting from the intensity-dependent nonlinear effect. here, a low-coherence perfect vortex beam(PVB) with a topological charge as high as 140 is realized based on the super-pixel wavefront-shaping technique. More importantly, a globally adaptive feedback algorithm(GAFA) is proposed to efficiently suppress the original intensity fluctuation and achieve a flat-top PVB with dramatically reduced beam speckle contrast. The GAFA-based flat-top PVB generation method can pave the way for high-intensity vortex beam generation,which is crucial for potential applications in ICF, laser processing, optical communication and optical trapping.

关键词： digital micromirror device flat-top beam orbital angular momentum perfect vortex beam random fiber laser

“Capture-activation-recapture” mechanism-guided design of double-atom catalysts for electrocatalytic nitrogen reduction

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Journal of Energy Chemistry 2024年第9期96卷 437-447页

作者： Cheng he Shiqi Yan Wenxue Zhang State Key laboratory for Mechanical Behavior of Materials School of Materials Science1nd EngineeringXi’an Jiaotong UniversityXi’an 710049ShaanxiChina School of Materials Science1nd Engineering Chang’an UniversityXi’an 710064ShaanxiChina

Compared with the traditional industrial nitrogen fixation, electrocatalytic methods, especially those utilizing double-atom catalysts containing nonmetals, can give good consideration to the economy and environmental protection. however, the existing “acceptance-donation” mechanism is only applicable to bimetallic catalysts and nonmetallic double-atom catalysts containing boron atoms. herein, a novel “capture-activation-recapture” mechanism for metal-nonmetal double-atom catalyst is proposed to solve the problem by adjusting the coordination environments of nonmetallic atoms and utilizing the activation effect of metal atoms on nitrogen. Based on this mechanism, the nitrogen reduction reaction (NRR) activity of 48 structures is calculated by density functional theory calculation, and four candidates are selected as outstanding electrocatalytic nitrogen reduction catalysts: Si-Fe@NG (U_(l) = –0.14 V), Si-Co@NG (U_(l)= –0.15 V), Si-Mo@BP1 (U_(l) = 0 V), and Si-Re@BP1 (U_(l) = –0.02 V). The analyses of electronic properties further confirm “capture-activation-recapture” mechanism and suggest that the difference in valence electron distribution between metal and Si atoms triggers the activation of N≡N bonds. In addition, a machine learning approach is utilized to generate an expression and an intrinsic descriptor that considers the coordination environment to predict the limiting potential. This study offers profound insight into the synergistic mechanism of TM and Si for NRR and guidance in the design of novel double-atom nitrogen fixation catalysts.

关键词： "Capture-activation-recapture"mechanism Double-atom catalyst Nitrogen reduction reaction Density functional theory

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.Y.Morassuti A.P.l Silva l.A.O.Nunes S.M.lima l.h.C.Andrade Optical and Photothermal Spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

Toxicity mechanisms of photodegraded polyvinyl chloride nanoplastics on pea seedlings

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 111-124页

作者： hao Wu Beibei he Bocheng Chen An liu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Nanoplasctics(NPs),which are very small in particle size,exert toxic effect to ***,compared to original NPs,photodegraded NPs would pose higher *** is because their relatively higher specific surface areas and the presence of additives which can more easily *** original NPs and aged NPs affect plant growth has not been widely *** work chose polyvinyl chloride NPs(PVC-NPs)that were subjected to up to 1000 h UV light radiation to explore the impact of PVC-NPs on the growth of pea seedlings(Pisum Sativum l.).The results indicated the existence of PVC-NPs with longer UV light radiation time and higher concentrations had more negative influences on pea seedlings’growth such as germination rate(decreased by 10.6%–22.5%),stem length(decreased by 2.8%–8.1%),dry weight(decreased by 6.3%–7.1%)and fresh weight(decreased by 6.7%–14.8%).It was also noted that photodegraded PVC-NPs resulted in damage to leaf stomata and roots,hindering photosynthesis and absorption of nutrients and hence the decrease in chlorophyll and soluble sugar *** to transcriptomic investigation results,the presence of aged PVC-NPs primarily influenced protein processing in endoplasmic reticulum(upregulated metabolic pathway)and phenylpropanoid biosynthesis(downregulated metabolic pathway)of pea *** results provide an in-depth understanding of how NPs influence the growth of plants.

关键词： Nanoplasctics Polyvinyl chloride Toxicity mechanisms Plant growth

Pulsations of Three Rapidly Oscillating Ap Stars TIC 96315731, TIC72392575, and TIC 318007796

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Research in Astronomy and Astrophysics 2024年第8期24卷 159-170页

作者： hai-Jian Zhong Dong-Xiang Shen Chun-hua Zhu he-lei liu Su-Fen Guo Guo-liang lü School of Physical Science and Technology Xinjiang University Xinjiang Astronomical Observatory National Astronomical ObservatoriesChinese Academy of Sciences

We analyze the frequencies of three known roAp stars,TIC 96315731,TIC 72392575,and TIC 318007796,using the light curves from the Transiting Exoplanet Survey *** TIC 96315731,the rotational and pulsational frequencies are 0.1498360 day-1and 165.2609 day-1,*** the case of TIC 72392575,the rotational frequency is 0.25551 *** detect a quintuplet of pulsation frequencies with a center frequency of135.9233 day-1,along with two signals within the second pair of rotational sidelobes of the quintuplet separated by the rotation *** two signals may correspond to the frequencies of a dipole *** TIC318007796,the rotational and pulsational frequencies are 0.2475021 day-1,192.73995 day-1,and196.33065 day-1,*** on the oblique pulsator model,we calculate the rotation inclination （i）and magnetic obliquity angle （b） for the stars,which provide the geometry of the pulsation *** the phases of the frequency quintuplets,the pulsation amplitude and phase modulation curves,and the results of spherical harmonic decomposition,we conclude that the pulsation modes of frequency quintuplets in TIC96315731,TIC 72392575,and TIC 318007796 correspond to distorted dipole mode,distorted quadrupole mode,and distorted dipole mode,respectively.

关键词： asteroseismology stars: chemically peculiar stars: oscillations (including pulsations) techniques: photometric

Effect of cold-working on corrosion induced damage in lug joints

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Defence Technology（防务技术） 2024年第6期36卷 175-182页

作者： Ramanath M.N Chikmath l. Murthy h. Department of Aerospace Engineering Indian Institute of Technology-MadrasChennai 600036India Department of Aeronautical Engineering KLS Gogte Institute of TechnologyBelagavi 590008India

lug joints are preferred joineries for transferring heavy loads to parent components in aerospace *** experience corrosion due to environmental conditions,improper surface finishes and rubbing displacement between the pin and *** causes damage of different sizes and shapes near the *** degradation due to corrosion-induced damage is modelled as a through-pit at one of the identified critical locations through stress *** effect of this pit on fatigue crack initiation life is ***-hole is pre-stressed by cold-working and the benefits of inducing plastic wake on the intended performance of the lug joint during the damages due to corrosion are brought out and compared with non-cold-worked *** analysis is performed on this lug joint with *** results obtained highlight the benefits of cold-working and the methodology can be extended to damage growth and analyse the effect of surface treatments for better structural integrity of components of aerospace vehicles.

关键词： lug joint Corrosion Crack initiation Cold-working Structural integrity

low-rank matrix recovery with total generalized variation for defending adversarial examples

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Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 432-445页

作者： Wen lI hengyou WANG lianzhi hUO Qiang he linlin CheN Zhiquan he Wing W.Y.Ng School of Science Beijing University of Civil Engineering and ArchitectureBeijing 100044China School of Computer Science and Engineering South China University of TechnologyGuangzhou 510006China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China Guangdong Key laboratory of Intelligent Information Processing Shenzhen 518060China Institute of Big Data Modeling and Technology Beijing University of Civil Engineering and ArchitectureBeijing 100044China

low-rank matrix decomposition with first-order total variation(TV)regularization exhibits excellent performance in exploration of image *** advantage of its excellent performance in image denoising,we apply it to improve the robustness of deep neural ***,although TV regularization can improve the robustness of the model,it reduces the accuracy of normal samples due to its *** our work,we develop a new low-rank matrix recovery model,called lRTGV,which incorporates total generalized variation(TGV)regularization into the reweighted low-rank matrix recovery *** the proposed model,TGV is used to better reconstruct texture information without *** reweighted nuclear norm and li-norm can enhance the global structure ***,the proposed lRTGV can destroy the structure of adversarial noise while re-enhancing the global structure and local texture of the *** solve the challenging optimal model issue,we propose an algorithm based on the alternating direction method of *** results show that the proposed algorithm has a certain defense capability against black-box attacks,and outperforms state-of-the-art low-rank matrix recovery methods in image restoration.

关键词： Total generalized variation low-rank matrix Alternating direction method of multipliers Adversarial example

Characterization of a Novel Esterase Belonging to Family V from Marinobacter flavimaris

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Journal of Ocean University of China 2024年第1期23卷 221-232页

作者： he Jingjing ZhANG Yunhui WU leilei WANG Yaru ZhANG he lIU Zhengang ShI Xiaochong Frontiers Science Center for Deep Ocean Multispheres and Earth System and College of Marine Life SciencesOcean University of ChinaQingdao 266003China laboratory for Marine Ecology and Environmental Science Laoshan LaboratoryQingdao 266237China Institute of Evolution&Marine Biodiversity Ocean University of ChinaQingdao 266003China

lipolytic enzymes have attracted enormous attentions because of their ability in ester hydrolysis,ester synthesis,transesterification and other biochemical *** are important sources of lipolytic enzymes applied in ***,a novel lipolytic enzyme encoded by esterase gene est1347 was identified in Marinobacter flavimaris Wll162,and was purified and *** lipolytic enzyme Est1347 consisted of 312 amino acid residues and a 21-amino-acids N-terminal signal peptide with a predicted molecular weight of 34.2 *** belongs to family V of bacterial lipolytic enzymes based on the amino acid sequence homology ***1347 is a mesophilic and alkali-resistant enzyme with the highest activity at 45℃and ph 8.5;it is stable at temperatures below 50℃and ph 7.5–***1347 showed a preference for middle-length chain substrate p-NPC10 and a wide range of other *** Km,Vmax,Kcat and Kcat/Km values of Est1347 for p-NPC10 in ph 8.5 at 45℃were 0.9411 mmol l^(−1),1285μmol min^(−1)mg^(−1),698.91 s^(−1)and 743.65 s^(−1)(mmol l^(−1))^(−1),*** is also tolerant to the metal ions,organic solvents and *** conclusion,the esterase Est1347 laid a foundation for further study of bacterial lipolytic enzyme family V.

关键词： esterase Marinobacter flavimaris enzymatic properties lipolytic enzyme family V

In-situ powder mixing for laser-based directed energy deposition of functionally graded materials

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Advances in Manufacturing 2024年第1期12卷 150-166页

作者： Ji-Peng Chen Shou-Chun Xie he huang School of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing210037People’s Republic of China Nanjing huirui Photoelectric Technology Co. LtdNanjing211121People’s Republic of China

The mixing of powders is a highly relevant field under additive manufacturing,however,it has attracted limited interest to *** in-situ mixing of various powders remains a significant *** paper proposes a new method utilizing a static mixer for the in-situ mixing of multiple powders through the laser-based directed energy deposition(DED)of functionally graded ***,a powder-mixing experimental platform was established;WC and 316l powders were selected for the mixing ***,scanning electron microscopy,energy dispersive spectroscopy,and image processing were used to visually evaluate the homogeneity and proportion of the in-situ mixed ***,powder-mixing simulations were conducted to determine the powder-mixing *** the simulations,a powder carrier gas flow field and particle mixing were ***,a WC/316l metal matrix composite sample was produced using laser-based DED to verify the application potential of the static *** was found that the static mixer could adjust the powder ratio online,and a response time of 1–2 s should be considered when adjusting the ratio of the mixed powder.A feasible approach for in-situ powder mixing for laser-based DED was demonstrated and investigated,creating the basis for functionally graded materials.

关键词： laser Deposition Static mixer Powder mixing Functionally graded materials