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Arsenic methylation and microbial communities in paddy soils under alternating anoxic and oxic conditions

Journal of Environmental sciences 2025年第2期148卷 468-475页

作者： Jing Liu Rui Pei Runzeng Liu Chuanyong Jing Wenjing Liu Shandong Key Laboratory of Environmental Processes and Health School of Environmental Science and EngineeringShandong UniversityQingdao 266237China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Arsenic(As)methylation in soils affects the environmental behavior of As,excessive accumulation of dimethylarsenate(DMA)in rice plants leads to straighthead disease and a serious drop in crop *** the mobility and transformation of methylated arsenic in redox-changing paddy fields is crucial for food ***,soils including unarsenic contaminated(N-As),low-arsenic(L-As),medium-arsenic(M-As),and high-arsenic(H-As)soils were incubated under continuous anoxic,continuous oxic,and consecutive anoxic/oxic treatments respectively,to profile arsenic methylating process and microbial species involved in the As *** anoxic-oxic(A-O)treatment,methylated arsenic was significantly increased once oxygen was introduced into the incubation *** methylated arsenic concentrations were up to 2-24 times higher than those in anoxic(A),oxic(O),and oxic-anoxic(O-A)treatments,under which arsenic was methylated slightly and then decreased in all four As concentration *** fact,the most plentiful arsenite S-adenosylmethionine methyltransferase genes(arsM)contributed to the increase in As ***(40.8%-62.4%),Firmicutes(3.5%-15.7%),and Desulfobacterota(5.3%-13.3%)were the major microorganisms related to this *** microbial increasedmarkedly and played more important roles after oxygen was introduced,indicating that they were potential keystone microbial groups for As methylation in the alternating anoxic(flooding)and oxic(drainage)*** novel findings provided newinsights into the reoxidation-driven arsenic methylation processes and the model could be used for further risk estimation in periodically flooded paddy fields.

关键词： Arsenic methylation Anoxic-oxic Straighthead disease arsM gene Microbial community

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An Improved key Mismatch Attack on Kyber 7

An Improved Key Mismatch Attack on Kyber

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7th International Conference on Cryptography, Security and Privacy, CSP 2023

作者： Wang, Yaru Jiang, Haodong Ma, Zhi State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou China

ISBN: (纸本)9798350323368

Recently, American National Institute of Standards and Technology (NIST) announced Kyber as the first KEM candidate to be standardized. The security of Kyber is based on the modular learning with errors (MLWE) problem, which achieves excellent efficiency and size. This work proposes an improved key mismatch on Kyber, which can reduce the number of queries required to recover the secret key. We first transform the problem of finding a certain parameter of ciphertexts into a quantum ordered search problem. Then we give the procedure of finding the value of a parameter in the ciphertexts by the quantum method. Finally, we instantiate this attack method on Kyber512, Kyber768 and Kyber1024. Compared with the existing attack algorithm, our improved attack reduces the number of queries for Kyber512, Kyber768 and Kyber1024 by 63%, 59% and 45%, respectively. © 2023 IEEE.

关键词： Security of data

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Rational design of ZnCdS/TpPa-1-COF heterostructure photocatalyst by strengthening the interface connection in solar hydrogen production reactions

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Nano Research 2024年第3期17卷 1027-1034页

作者： Di Yang Zhi-Gang Li Xinghao Zhang Zenghuan Ren Weihan Lu Haining Liu Xiaomeng Guo Jijie Zhang Xian-He Bu Tianjin Key Laboratory of Metal and Molecule-Based Material Chemistry School of Materials Science and EngineeringNankai UniversityTianjin 300350China College of Chemistry and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018China State Key Laboratory of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China

ZnCdS quantum dots(QDs)are highly coveted in photocatalysis research for their exceptional visible-light responses and high light-absorption ***,their practical application is hindered by their tendency to aggregate,due to having high surface *** address this issue,herein,a heterostructure is synthesized by growing ZnCdS QDs with a size of approximately 5 nm onto the surface of a two-dimensional(2D)covalent organic framework(COF),*** approach suppresses the aggregation of the QDs and improves their *** ZnCdS/TpPa-1-COF composite exhibited a peak hydrogen evolution rate of 6244.16μmol·g^(-1)·h^(-1),which was 2.89 and 4.18 times greater than that of ZnCdS and TpPa-1-COF,*** zero-dimensional/two-dimensional(0D/2D)heterojunction formed by ZnCdS and TpPa-1-COF generates a strong interfacial force,which is attributed to the intimate contact between the *** connections accelerate charge separation,improve the utilisation of reduced electrons,and reduce the extent of agglomeration of the ZnCdS QDs,thereby resulting in high hydrogen production activity of the ***,the photocatalytic mechanism is studied using Kelvin probe force microscopy and theoretical *** study offers a novel approach for creating sulfide photocatalysts and is crucial for investigating the potential practical applications of the related photocatalysts.

关键词： covalent organic frameworks quantum dots photocatalysis hydrogen generation heterojunction

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Microstructure evolution and shape memory behaviors of Ni_(47)Ti_(44)Nb_(9)alloy subjected to multistep thermomechanical loading with different prestrain levels

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Journal of Materials science & Technology 2024年第4期171卷 80-93页

作者： Y.H.Zhang H.Li Z.W.Yang X.Liu Q.F.Gu State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of High-Performance Precision Forming Technology and Equipment Northwestern Polytechnical UniversityXi’an 710072China

Ni_(47)Ti_(44)Nb_(9)shape memory alloy(SMA)is a promising material in the aerospace field due to its wide transformation *** application of shape memory effect depends on multistep thermomechan-ical loading,viz.,low-temperature deformation and subsequent heating to ***-temperature deformation prestrain plays a pivotal role in shape memory properties tailoring of SMA ***,microstructure evolution and deformation mechanisms of Ni_(47)Ti_(44)Nb_(9)SMA subjected to vari-ous prestrain levels are still *** this end,microstructure evolution and shape memory behaviors of Ni_(47)Ti_(44)Nb_(9)alloy subjected to multistep thermomechanical loading with prestrain levels of 8%-16%at-28℃(M_(s)+30℃)were *** results demonstrate that the stress-strain curve of the specimen exhibits four distinct stages at a maximal prestrain of 16%.Whereas stageⅡand stageⅢend at prestrains of∼8%and∼12%,*** stageⅡ,the stress-induced martensitic transformation is accompanied by the dislocation slip of the NiTi matrix andβ-Nb *** stageⅢ,in addition to the higher density of dislocations and further growth of stress-induced martensite variants(SIMVs),(001)compound twins are introduced as a result of the(001)deformation twinning in stress-induced ***{20-1}martensite twins are gradually introduced in stageⅣ.Correspondingly,after subsequent unloading and heating,a higher density of{114}austenite twins form in the specimen with a larger prestrain of 16%.With increasing prestrain from 8%to 16%,the recoverable strainε_(re)^(T)upon heating increases first and then ***ε_(re)^(T)obtains a maximum of 7.03%at 10%prestrain and de-creases to 6.17%at 16%*** increase ofε_(re)^(T)can be attributed to the formation of new SIMVs,the further growth of existing SIMVs,and the recoverable(001)compound *** the decrease ofε_(re)^(T)is mainly associated with the irrecoverable strain by{20−1}martensite *** effe

关键词： Ni_(47)Ti_(44)Nb_(9)shape memory alloy Wide transformation hysteresis Thermomechanical loading Microstructure evolution Shape memory behaviors Stress-induced martensitic transformation Deformation twinning

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Weakly supervised action anticipation without object annotations

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Frontiers of Computer science 2023年第2期17卷 101-110页

作者： Yi ZHONG Jia-Hui PAN Haoxin LI Wei-Shi ZHENG School of Computer Science and Engineering Sun Yat-sen UniversityGuangzhou 510006China Key Laboratory of Machine Intelligence and Advanced Computing Ministry of EducationGuangzhou 510006China

Anticipating future actions without observing any partial videos of future actions plays an important role in action prediction and is also a challenging *** obtain abundant information for action anticipation,some methods integrate multimodal contexts,including scene object ***,extensively labelling each frame in video datasets requires considerable *** this paper,we develop a weakly supervised method that integrates global motion and local finegrained features from current action videos to predict next action label without the need for specific scene context ***,we extract diverse types of local features with weakly supervised learning,including object appearance and human pose representations without ground ***,we construct a graph convolutional network for exploiting the inherent relationships of humans and objects under present *** evaluate the proposed model on two datasets,the MPII-Cooking dataset and the EPIC-Kitchens dataset,and we demonstrate the generalizability and effectiveness of our approach for action anticipation.

关键词： action anticipation weakly supervised learning relation modelling graph convolutional network

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Simultaneous enhancement of piezoelectricity and temperature stability in Pb(Ni_(1/3)Nb_(2/3))O_(3)-PbZrO_(3)-PbTiO_(3)piezoelectric ceramics via Sm-modification

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Journal of Advanced Ceramics 2024年第10期13卷 1578-1589页

作者： Kai Li Shan Cong Lang Bian Zhenting Zhao Jie Wu Junfeng Zhao Duoduo Zhang Haijuan Mei Enwei Sun Xudong Qi Weiping Gong Bin Yang Guangdong Provincial Key Laboratory of Electronic Functional Materials and Devices Huizhou UniversityHuizhou 516001China Condensed Matter Science and Technology Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin 150080China Electronic Materials Research Laboratory(Key Lab of Education Ministry) State Key Laboratory for Mechanical Behavior of Materials and School of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China School of Physics and Electronic Engineering Key Laboratory for Photonic and Electronic Bandgap MaterialsMinistry of EducationHarbin Normal UniversityHarbin 150025China

The development of piezoelectric ceramics characterized by both large piezoelectric response and high-temperature stability is imperative for the advancement of practical electromechanical ***,existing high-performance piezoelectric ceramics often encounter compromised temperature stability because ferroelectric phase transitions occur within low-temperature *** this work,we focused on Sm-doped Pb(Ni_(1/3)Nb_(2/3))O_(3)-PbZrO_(3)-PbTiO_(3)(PNN-PZT:Sm)ceramics with a tetragonal(T)-phase structure to achieve the desired combination of high piezoelectricity and high temperature *** results indicate that 2 mol%Sm-doped samples exhibit a large piezoelectric constant(d_(33))of 575 pC/N,an effective piezoelectric strain coefficient(d_(33)*)of 890 pm/V,and a high ferroelectric-to-paraelectric phase transition temperature(Tm)of 279℃.Remarkably,d_(33) experiences only a 2.6%variation over the temperature range of 30-250℃,while d_(33)*changes by 8%within the temperature range of 30-180℃.Microstructural and domain structure analyses suggest that Sm-doping effectively reduces the grain size,leading to a decreased domain size,thereby achieving excellent electromechanical *** superior temperature stability is attributed to the suppressive effect of Sm-doping on the R-T ferroelectric phase *** studies suggest that Sm-doping represents an effective strategy for achieving the collaborative optimization of piezoelectricity and temperature stability through grain and domain engineering techniques for perovskite ferroelectric materials.

关键词： PNN-PZ-PT ceramics Sm-doping piezoelectricity temperature stability domain structures

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Delayed optical feedback-regulated artificial soliton molecule in a femtosecond optical parametric oscillator

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PhotoniX 2024年第1期5卷 34-53页

作者： Yu Cai Jintao Fan Fanchao Meng Youjian Song Minglie Hu Ultrafast Laser Laboratory State Key Laboratory of Precision Measurement Technology and InstrumentsTianjin UniversityTianjin 300072China Ultrafast Laser Laboratory College of Precision Instrument and Optoelectronics EngineeringTianjin UniversityTianjin 300072China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China

Soliton molecules(SMs)play a crucial role in nonlinear optical systems,enriching our understanding of nonlinear science through the study of their interaction *** passively mode-locked fiber lasers offer an efficient platform for generating diverse types of SMs,the complex internal dynamics of the laser often pose challenges in achieving predetermined temporal separations between ***,we implement a delayed optical feedback technique within a femtosecond optical parametric oscillator,enabling the generation of SMs with precise and controllable temporal separations.A theoretical model,which models the intracavity iterations of the signal with a simplified Ikeda map,is proposed to study the impact of parametric gain,intracavity feedback delay,and cavity length on the internal separations of the *** experimental results confirm that adjusting the cavity length allows for producing desired temporal separations within *** reveal the evolution dynamics of the SMs,we further develop a rigorous numerical model using the carrier-resolved Forward Maxwell Equation,which is capable of modeling ultra-broadband complex dynamics based on a single equation without relying on the slowly-varying envelope *** numerical model unveils the rich formation dynamics of the SMs at various separations,which confirms the critical role of the gain window provided by the *** work opens up new opportunities for the on-demand generation of SMs and provides valuable insights into the complex dynamics in femtosecond optical parametric oscillator systems with optical delayed feedback.

关键词： Soliton molecule Femtosecond Optical parametric oscillator Delayed optical feedback

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ALEmu: A Framework for Application-layer Programs Emulation of Embedded Devices 4

ALEmu: A Framework for Application-layer Programs Emulation ...

引用

4th International Conference on Computer engineering and Application, ICCEA 2023

作者： He, Heng Xiong, Xiaobing Zhao, Yuntian State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou China

ISBN: (纸本)9798350347548

The difference between real devices and virtual environments causes a low success rate of application-layer program emulation when the firmware is operating in full-system emulation during the dynamic analysis of the firmware of embedded devices. In this paper, we propose ALEmu, an emulation framework for application-layer programs, which can effectively improve the emulation success rate of application-layer programs in embedded device firmware through automatic preprocessing of target programs, building configuration libraries, and hooking external program calls. When we test ALEmu on a variety of real-world devices, including routers and IP cameras, we find that it performs more successfully and accurately than the current state-of-the-art full-system emulation frameworks like Firmadyne and FirmAE. © 2023 IEEE.

关键词： Firmware

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High-strength,electrically insulated industrial meta-aramid paper reinforced with polyethylene terephthalate microfibre pulp in a sandwich structure

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High Voltage 2024年第6期9卷 1402-1413页

作者： Meijun Chen Songjun Yao Guobin Zhu Mengyun Wu Zhiying Li Siwei Xiong Shiwen Yang Hua Wang Liangbo Zhu Luoxin Wang State Key Laboratory of New Textile Materials&Advanced Processing Technology College of Materials Science and EngineeringWuhan Textile UniversityWuhanChina High-Tech Organic Fibers Key Laboratory of Sichuan Province ChengduSichuanChina

The weak interfacial strength and porous structure of the meso-aramid paper cause mechanical and insulating *** density,regulating pore structure,and improving interfacial interactions of meso-aramid are crucial for promoting the perfor-mance of meso-aramid papers.A PMIA/polyethylene terephthalate(PET)composite paper was prepared using the wet method with meso-aramid short cut fibres(PMIA)and PET pulp as raw *** sandwich-structured PMIA/PET paper was achieved by covering PET microfiber non-wovens served as the surface layer while the PMIA/PET composite paper acted as the core *** the high-temperature hot pressing process,the PET pulp transformed into a viscous melt that coated on aramid fibres in between layers,forming a typical‘reinforced concrete’interface structure within the core layer of the PMIA/PET composite *** PET non-wovens on top and bottom surfaces were converted into a dense PET film that filled and covered the holes and defects in the PMIA/PET composite *** unique structure enabled the sandwich-structured PMIA/PET composite paper to exhibit excellent tensile strength(80.41 N/cm)and breakdown strength(56.35 kV/mm),surpassing most reported performances of meso-aramid papers in *** work not only provides novel insights for pre-paring high-performance meso-aramid papers,but also shows potential applications for other materials and structures.

关键词： strength structure sandwich

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On the Factors Influencing the High Stretch-Flangeability of a Low-Density 1180 MPa Fe-Mn-Al-C-Nbδ-QP Steel

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1291-1300页

作者： Dan‑Dan Cui Peng Chen Peng‑Fei Wang Xiao‑Wu Li Department of Materials Physics and Chemistry School of Materials Science and Engineeringand Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

Low-densityδ-quenching and partitioning(δ-QP)steels with excellent strength and ductility have been recently ***,there are still rare reports on the formability of δ-QP steels,which are critical for satisfying the manufacture of structural parts during the application in automotive *** the present work,an 1180 MPa Fe–Mn–Al–C–Nbδ-QP steel with a high ductility was adopted for the stretch–flangeability ***δ-QP steel was developed by separated quenching and partitioning processes.A good hole expansion ratio(HER)of 34.9±0.9%was obtained in the quenched steel,but it has been further increased to 52.2%by the tempering *** improved stretch–flangeability was attributed to the enhanced austenite stability and deformation *** the one hand,the stability of austenite was increased by carbon partitioning during tempering,which reduced crack possibility via the suppression of the fresh martensite *** the other hand,the tempering treatment released the internal stress caused by martensitic transformation and reduced the difference in strength among different phases,resulting in an increase in the resistance to crack initiation and propagation.

关键词： Hole expansion ratio Low-densityδ-quenching and partitioning(δ-QP)steel Stretch-flangeability Austenite stability Deformation uniformity

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