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Pronounced temporal changes in soil microbial community and nitrogen transformation caused by benzalkonium chloride

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Journal of Environmental Sciences 2023年第4期126卷 827-835页

作者： rui yang Shaohong Zhou Lilan Zhang Cunli qin State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China Key Laboratory of Three Gorges Reservoir Region’s Eco-Environment Ministry of EducationChongqing UniversityChongqing 400045China

As one typical cationic disinfectant, quaternary ammonium compounds(qACs) were approved for surface disinfection in the coronavirus disease 2019 pandemic and then unintentionally or intentionally released into the surrounding environment. Concerningly, it is still unclear how the soil microbial community succession happens and the nitrogen(N)cycling processes alter when exposed to qACs. In this study, one common qAC(benzalkonium chloride(BAC) was selected as the target contaminant, and its effects on the temporal changes in soil microbial community structure and nitrogen transformation processes were determined by q PCR and 16S r RNA sequencing-based methods. The results showed that the aerobic microbial degradation of BAC in the two different soils followed first-order kinetics with a half-life(4.92 vs. 17.33 days) highly dependent on the properties of the soil. BAC activated the abundance of N fixation gene(nif H) and nitrification genes(AOA and AOB) in the soil and inhibited that of denitrification gene(nar G). BAC exposure resulted in the decrease of the alpha diversity of soil microbial community and the enrichment of Crenarchaeota and Proteobacteria. This study demonstrates that BAC degradation is accompanied by changes in soil microbial community structure and N transformation capacity.

关键词： Benzalkonium chloride Soil Degradation kinetics Microbial community structure Nitrogen cycling

Generalizing Lyubashevsky-Wichs trapdoor sampler for NTRU lattices

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Science China(Information Sciences) 2022年第5期65卷 273-275页

作者： yang TAO Yunfeng JI rui ZHANG State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of Sciences School of Cyber Security University of Chinese Academy of Sciences

Dear editor,At the core of lattice-based cryptography, a linear function f（x） = Ax mod q with a random matrix A ∈ Z;and a short vector x ∈ Z;plays an essential role, especially in the lattice-based signature, identity-based encryption and attribute-based encryption. It is a one-way function introduced by Ajtai and with a proper trapdoor, the short solution x can be recovered without leaking any trapdoor information, thus a trapdoor sampler.

关键词： trapdoor sampler NTRU lattice hash-and-sign lattice-based signature post-quantum cryptography

Tunable-q contourlet transform for image representation

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Journal of Systems Engineering and Electronics 2013年第1期24卷 147-156页

作者： Haijiang Wang qinke yang rui Li Zhihong Yao Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources College of Urban and Environment Science Shanxi Normal University College of Urban and Environmental Sciences Northwest University College of Resources and Environment North China University of Water Resources and Electric Power

A novel tunable-quality-factor （tunable-q） contourlet transform for geometric image representation is proposed. The Laplacian pyramid in original contourlet decomposes a signal into channels that have the same bandwidth on a logarithmic scale, and is not suitable for images with different behavior in frequency domain. We employ a new tunable-q decomposition defined in the frequency domain by which one can flexibly tune the bandwidth of decomposition channels. With an acceptable redundancy, this tunable-q contourlet is also anti-aliasing and its basis is sharply localized in the desired area of frequency and spatial domain. Our experiments in nonlinear approximation and denoising show that the contourlet using a better-suitable quality factor can achieve a more promising performance and often outperform wavelets and the previous contourlets both in visual quality and in terms of peak signal-to-noise ratio.

关键词： contourlet quality factor (q-factor) anti-aliasing mul-tiscale decomposition.

Coupling Characteristics of DFIG-based WT Considering Reactive Power Control and Its Impact on Phase/Amplitude Transient Stability in a Rotor Speed Control Timescale

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CSEE Journal of Power and Energy Systems 2022年第2期8卷 511-522页

作者： Wangqianyun Tang Jiabing Hu rui Zhang Xu Chen Zhengang yang Electric Power Research Institute China Southern Power GridGuangzhou 510080China State Key Laboratory of Advanced Electro-magnetic Engineering and Technology and School of Electrical and Electronic Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Advanced Electro-magnetic Engineering and Technology and School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China China Southern Power Grid Guangzhou 510080China

The transient stability issues caused by doubly fed induction generator(DFIG)-based wind turbines(WTs)are receiving increasing *** q-axis reactive power control(qCtrl),as an essential part of DFIG-based WTs,has a significant impact on its transient *** this paper,the impact of qCtrl on the phase/amplitude transient stability of a DFIGbased WT-dominated system is analyzed from the perspective of internal voltage amplitude-phase coupling ***,an amplitude/phase dynamic model of a DFIG-based WT in rotor speed control timescale(in seconds,corresponding to traditional electromechanical timescale)is ***,in comparison with familiar synchronous generators(SGs),an inherently amplitude-phase characteristic of internal voltage for a DFIG-based WT is ***,taking the DFIG-based WTdominated system as an example,the impact of qCtrl on system transient stability via the internal coupling paths is analyzed.A novel phase-amplitude coupling instability mechanism is found,which is different from that in a traditional SG-dominated ***,the effects of different qCtrl strategies on transient stability are discussed.

关键词： Amplitude-phase response coupling characteristic reactive power control instability mechanism transient stability

Sm and Mn co-doped PMN-PT piezoelectric ceramics:Defect engineering strategy to achieve large d_(33)and high q_(m)

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Journal of Materials Science & Technology 2023年第6期137卷 143-151页

作者： Yixiao yang Enwei Sun Zhimin Xu Huashan Zheng Bin yang rui Zhang Wenwu Cao Condensed Matter Science and Technology Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin 150080China Department of Mathematics and Materials Research Institute The Pennsylvania State UniversityUniversity ParkPA 16802USA

PbTiO_(3)-based piezoelectric ceramics are key materials for developing various electromechanical *** high-power ultrasonic transducers,piezoelectric ceramics are required to possess large piezo-electric coefficient(d_(33))and high mechanical quality factor(q_(m)).Although acceptor dopants can im-prove q_(m),they also deteriorate d_(33).If suitable piezoelectricity-beneficial donor dopants can be intro-duced into acceptor-doped ceramics,it is very possible to obtain large d_(33)and high q_(m)simultaneously in donor and acceptor co-doped *** this work,a series of x mol%Sm and y mol%Mn co-doped Pb(Mg_(1/3)Nb_(2/3))O_(3)-30PbTiO_(3)(PMN-30PT:x Sm,y Mn)ceramics were prepared by the solid-phase sintered *** crystal structure,local domain structure and electromechanical properties were sys-tematically *** performances were obtained in PMN-30PT:2.5Sm,1-2Mn ceramics with d_(33)=860-543 pC/N,q_(m)=495-754,and dielectric loss tanδ=*** high performance origi-nates from the combined effects of(Mn″Ti−V_(o)^(••))^(×)defect dipoles and the local structural heterogeneity.

关键词： PMN-PT ceramics Sm and Mn co-doped Electromechanical properties Defect dipoles Local structural heterogeneity

A Note on a Diffusive Predator-prey Model and Its Steady-state System

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Acta Mathematica Sinica,English Series 2010年第5期26卷 963-974页

作者： rui PENG Ming Xin WANG Guo Ying yang Institute of Nonlinear Complex Systems College of Science China Three Gorges University Yichang 443002 P. R. China Department of Mathematics Southeast University Nanjing 210096 P. R. China Department of Mathematics Henan Polytechnic University Jiaozuo 454100 P. R. China

In this note, a diffusive predator-prey model subject to the homogeneous Neumann bound- ary condition is investigated and some qualitative analysis of solutions to this reaction-diffusion system and its corresponding steady-state problem is presented. In particular, by use of a Lyapunov function, the global stability of the constant positive steady state is discussed. For the associated steady state problem, a priori estimates for positive steady states are derived and some non-existence results for non-constant positive steady states are also established when one of the diffusion rates is large enough. Consequently, our results extend and complement the existing ones on this model.

关键词： a diffusive predator-prey model steady states global stability a priori-estimates non-existence

Vortex analysis of water flow through gates by different vortex identification methods

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Journal of Hydrodynamics 2023年第1期35卷 112-124页

作者： Chun-ying Shen rui-guo yang Shan qing Shi-hua He Faculty of Electrical Power Engineering Kunming University of Science and TechnologyKunming650500China

The pre-gate suction vortex,gate-bottom-edge transverse vortex,gate-slot vertical vortex,and downstream-of-gate return vortex are important factors affecting the flow instability of flat gates,which may lead to fatigue failure in severe *** study used the volume of fluid(VOF)model and large eddy simulation(LES)method to accurately capture the transient turbulence characteristics of flow under different water flow conditions and reveal the flow field and vortex *** q—criterion,Omega(Ω)method,and latest third-generation Liutex vortex identification method were used to analyze and compare the pre-gate suction vortex,gate-slot vertical vortex,and downstream-of-gate return vortex,focusing on the ability of each vortex identification method to capture the flow field information and vortex *** results reveal that theΩmethod and Liutex method are less dependent on the threshold value,and the Liutex method captures a wide range of pre-gate *** flow conditions cause changes in the vortex structure of over-gate *** the relative opening of the gate is smaller,the intensity of the vortices in the flow field around the gate is greater,the return vortices downstream of the gate are more disordered,and the vortex changes are more violent,which in turn affects the efficient and stable operation of the gate.

关键词： Vortex features vortex identification methods Liutex Ωmethod q-criterion large eddy simulation(LES)

Application of PCA and HCA to the Structure-activity Relationship(SAR) Study of Fluoroquinolones

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1351-1358页

作者： LI Xiao-Hong ZHANG rui-Zhou CHENG Xin-Lu yang Xiang-Dong Institute of Atom and Molecular Physics Sichuan University Chengdu 610065 China Xinxiang Teacher＇s College Xinxiang 453000 China

Density functional theory （DFT） was used to calculate a set of molecular descri ptors （properties） for 14 fluoroquinolones with *** activity. Principal component analysis （PCA） and hierarchical cluster analysis （HCA） were employed in order to reduce dimensionality and investigate which subset of variables should be more effective for classifying fluoroquinolones according to their *** activity degree. The PCA shows that the variables of ELUMO, AEHL, μ, q2, q3, q5, q6, qB, LogP, MR and MP are responsible for the separation between compounds with higher and lower *** activities. The HCA results are similar to those obtained with PCA. By using the chemometric results, 4 synthetic compounds were analyzed through PCA and HCA, and 2 of them are proposed as active molecules against ***, which is consistent with the results of clinic experiments. The methodologies of PCA and HCA provide a reliable rule for classifying new fluoroquinolones with *** activity.

关键词： structure-activity relationship DFT PCA HCA

Effects of short-term heat stress on PSII and subsequent recovery for senescent leaves of Vitis vinifera L. cv. Red Globe

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Journal of Integrative Agriculture 2018年第12期17卷 2683-2693页

作者： ZHANG Kun CHEN Bai-hong HAO Yan yang rui WANG Yu-an Horticulture College Gansu Agricultural UniversityLanzhou 730070P.R.China Institute of Fruit and Floriculture Research Gansu Academy of Agricultural SciencesLanzhou 730070P.R.China

Heat stress occurs frequently in energy-saving sunlight greenhouses(ESSG) at the late growth stage. Three-year delayed cultivation(DC) of the Red Globe cultivar of Vitis vinifera L. was used to clarify the physiological mechanisms of short-term heat stress on PSII and subsequent recovery from heat stress. By November, the photosynthetic function had declined and the fall in transpiration rate(E) with heating time increased the possibility of heat damage. In July, the most obvious increase was in the relative variable fluorescence at J point at 40°C, and in November it changed to K point. The 5 min of heat treatment resulted in a significant increase of the relative variable fluorescence at 0.3 ms(W), and after 10 min of heat treatment, the number of reactive centres per excited cross section(RC/CS), probability that a trapped exciton moves an electron into the electron transport chain beyond q–(at t=0)(Ψ) and quantum yield of electron transport at t=0(φ) decreased significantly(P<0.05), suggesting that the reaction centre, donor and acceptor side of photosystem II(PSII) were all significantly inhibited(P<0.05) and that the thermal stability of the photosynthetic mechanism was reduced. The inhibition of energy fluxes for senescent leaves in November was earlier and more pronounced than that for healthy leaves, which did not recover from heat stress of more than 15 min after 2 h recovery at room temperature.

关键词： short-term heat stress leaf senescence chlorophyll a fluorescence arid desert region delayed cultivation