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火龙果连作土壤细菌多样性与酶活性对酚酸类代谢产物的响应特征

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农业生物技术学报 2025年第1期33卷 30-42页

作者：谢勇俊秦文连周婧王孟佳潘小卓秦孝杰唐景美王一兵广西民族大学海洋与生物技术学院/广西多糖材料与改性重点实验室广西南亚热带农业科学研究所

随着火龙果(Hylocereus undatus)种植年限的增加，酚酸类代谢产物会逐渐在土壤中积累，引起土壤病原细菌、真菌及线虫等定殖，最终导致连作障碍的发生。本研究采用纯培养技术，从连作6年和3年的火龙果根际土壤中分离出可培养细菌，并通... 详细信息

随着火龙果(Hylocereus undatus)种植年限的增加，酚酸类代谢产物会逐渐在土壤中积累，引起土壤病原细菌、真菌及线虫等定殖，最终导致连作障碍的发生。本研究采用纯培养技术，从连作6年和3年的火龙果根际土壤中分离出可培养细菌，并通过16S r RNA基因序列进行种属鉴定。同时，采用土壤酶活性测定法研究不同种植年限火龙果土壤的酶活变化，利用高效液相色谱法(high performance liquid chromatography, HPLC)测定土壤中酚酸类代谢产物的种类及含量，分析土壤细菌与酶活性对酚酸类代谢产物的响应关系。结果显示，连作使火龙果中的细菌群落多样性增加，从火龙果的根际土壤中分离出4门、5纲、10目、16科、21属、56种共112株细菌，其中假单胞菌属(Pseudomonas)、伯克霍尔德菌属(Burkholderia)和芽胞杆菌属(Bacillus)等生防菌的相对丰度下降了23.36%。火龙果的连作种植导致土壤中过氧化氢酶和纤维素酶活性下降，脲酶和蔗糖酶活性上升。连作导致没食子酸、阿魏酸、水杨酸和苯甲酸的含量分别增加了163.80%、194.92%、341.57%和175.93%。响应关系分析显示，酚酸与微生物群落结构之间具有一定的关联性。上述结果表明，连作种植导致没食子酸、阿魏酸、水杨酸和苯甲酸等酚酸物质积累，引起了土壤微生物群落结构的失衡，有益微生物减少，土壤酶活力发生改变，植物营养物质的吸收受到影响，最终导致连作障碍的产生。本研究为后续开发具有降解酚酸功能的微生物菌剂及火龙果的田间管理技术提供基础数据。

关键词：火龙果连作障碍酚酸土壤酶活性土壤微生物

Effects of carnosine on the evoked potentials in hippocampal CA1 region

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第7期10卷 505-511页

作者： Zhou-yan FENG xiao-jing ZHENG jing WANG Key Lab of Biomedical Engineering of Ministry of Education College of Biomedical Engineering and lnstrument Science Zhejiang University Hangzhou 310003 China

Objective： To directly examine the effects ofcarnosine on neuronal excitation and inhibition in rat hippocampus in vivo. Methods： Artificial cerebrospinal fluid with carnosine was directly administrated over the exposed rat hippocampus. The changes of neuron activity in the CA1 region of hippocampus were evaluated by orthodromically- and antidromically-evoked potentials, as well as paired-pulse stimulation paradigm. Results： In both orthodromic and antidromic response potentials, carnosine transformed population spikes （PSs） with single spike into epileptiform multiple spikes. In addition, similar to the effect of 7-aminobutyric acidA （GABAA） antagonist picrotoxin, camosine decreased paired-pulse stimulating depression significantly. However, no significant change was observed in the spontaneous field potentials during the application of carnosine. Conclusion： The results indicate a disinhibition-induced excitation effect of carnosine on the CA1 pyramidal neurons. It provides important information against the application of carnosine as a potential anticonvulsant in clinical treatment.

关键词： Carnosine Hippocampus Evoked potential Epileptic seizure

EFFECT OF A MOVING BOUNDARY ON THE FLUID TRANSIENT FLOW IN LOW PERMEABILITY RESERVOIRS

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Journal of Hydrodynamics 2012年第3期24卷 391-398页

作者： LUO Wan-jing WANG xiao-dong School of Energy Resources China University of Geosciences Beijing 100083 China

In a low permeability reservoir, the existence of a moving boundary is considered in the study of the transient porous flow with threshold pressure gradient. The transmission of the moving boundary directly indicates the size of the drainage area as well as the apparent influences on the pressure behavior. The nonlinear transient flow mathematical model in which the threshold pressure gradient and the moving boundary are incorporated is solved by advanced mathematical methods. This paper presents some new analytical solutions describing the pressure distribution at a constant rate and the production decline in a constant pressure production with the boundary propagation. It is shown that the greater the threshold pressure gradient, the slower the transmission of the moving boundary, the larger the pressure loss will be, and there is no radial flow in the middle and later phases of the wellface pressure for a well at a constant rate. We have the the maximum moving boundary at a specific drawdown pressure for a low permeability reservoir The greater the threshold pressure gradient, the smaller the maximum moving boundary distance, the quicker the production decline for a well in a constant pressure production will be. The type curve charts for the modern well test analysis and the rate transient analysis with a moving boundary are obtained and the field test and the production data are interpreted as examples to illustrate how to use our new results.

关键词： threshold pressure gradient moving boundary well test analysis low permeability reservoir rate transient analysis

Photocatalytic nonoxidative coupling of methane to ethylene over carbon-doped ZnO/Au catalysts

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Science China Chemistry 2023年第11期66卷 3252-3261页

作者： jing Wang Yuhao Peng Wei xiao College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072China

A photocatalytic nonoxidative coupling of methane to multi-carbon compounds remains a huge challenge due to its high dissociation energy of C–H bonds and sluggish charge carrier ***-modified carbon-doped ZnO(C-ZnO/Au)photocatalyst is constructed by an interfacial modification-assisted self-assembly approach for efficient photocatalytic nonoxidative coupling of methane to ethylene and hydrogen(2CH_4=C_2H_4+2H_2).Benefitting from the presence of C-ZnO/Au interfaces,the catalyst not only weakens the excitonic confinement to improve the photogenerated charge carrier separation,but also enhances the stability of lattice oxygen to suppress C_2H_4 ***,this hybrid catalyst also accelerates the generation of Zn~+–O~–pairs to activate C–H bonds,stabilizes the important reaction intermediate(*OCH_3)to achieve the C–C coupling,and promotes the generation of low-valence Zn to accelerate the dehydrogenation of the*OC_2H_5 into C_2H_***,a stable photocatalytic methane conversion performance can be achieved over C-ZnO/Au heterojunctions with a stoichiometric generation of the oxidation product(C_2H_4,45.85μmol g~(-1)h~(-1))and reduction product(H_2,88.07μmol g~(-1)h~(-1)).This work provides deep insights into the elemental doping and oxide/Au interfaces for the enhanced photocatalytic activity and product selectivity under mild conditions in the absence of extra oxidants.

关键词： carbon-doped ZnO charge separation C–H bond activation photocatalytic nonoxidative coupling of methane

Distributed and Consensus Optimization for Non-smooth Image Reconstruction

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Journal of the Operations Research Society of China 2015年第2期3卷 117-138页

作者： xiao-jing Ye Department of Mathematics and Statistics Georgia State UniversityAtlantaGA 30303USA

We present a primal-dual algorithm with consensus constraints that can effectively handle large-scale and complex data in a variety of non-smooth image reconstruction *** particular,we focus on the case that the data fidelity term can be decomposed into multiple relatively simple functions and deployed to parallel computing units to cooperatively solve for a consensual solution of the original *** this case,the subproblems usually have closed form solution or can be solved efficiently at local computing units,and hence the per-iteration computation complexity is very low.A comprehensive convergence analysis of the algorithm,including convergence rate,is established.

关键词： Distributed optimization Parallel computing Consensus Total variation Image reconstruction

Adaptive NN stabilization for stochastic systems with discrete and distributed time-varying delays

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Journal of Systems Engineering and Electronics 2011年第6期22卷 954-966页

作者： jing Li Junmin Li Yuli xiao Department of Mathematics Xidian University Xi＇an 710071 R R. China School of Telecommunications Engineering Xidian University Xi＇an 710071 P. R. China

A new adaptive neural network（NN） output-feedback stabilization controller is investigated for a class of uncertain stochastic nonlinear strict-feedback systems with discrete and distributed time-varying delays and unknown nonlinear functions in both drift and diffusion ***,an extensional stability notion and the related criterion are ***,a nonlinear observer to estimate the unmeasurable states is designed,and a systematic backstepping procedure to design an adaptive NN output-feedback controller is proposed such that the closed-loop system is stable in *** effectiveness of the proposed control scheme is demonstrated via a numerical example.

关键词： distributed delay output-feedback stabilization nonlinear observer stochastic nonlinear strict-feedback system adaptive neural network control(ANNC).

Plasma-assisted ammonia synthesis under mild conditions for hydrogen and electricity storage:Mechanisms,pathways,and application prospects

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Frontiers in Energy 2024年第4期18卷 418-435页

作者： Feng GONG Yuhang jing Rui xiao Key Laboratory of Energy Thermal Conversion and Process Measurement and Control of the Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China

Ammonia,with its high hydrogen storage density of 17.7 wt.%(mass fraction),cleanliness,efficiency,and renewability,presents itself as a promising zero-carbon ***,the traditional Haber−Bosch(H−B)process for ammonia synthesis necessitates high temperature and pressure,resulting in over 420 million tons of carbon dioxide emissions annually,and relies on fossil fuel *** contrast,dielectric barrier discharge(DBD)plasma-assisted ammonia synthesis operates at low temperatures and atmospheric pressures,utilizing nitrogen and hydrogen radicals excited by energetic electrons,offering a potential alternative to the H−B *** method can be effectively coupled with renewable energy sources(such as solar and wind)for environmentally friendly,distributed,and efficient ammonia *** review delves into a comprehensive analysis of the low-temperature DBD plasma-assisted ammonia synthesis technology at atmospheric pressure,covering the reaction pathway,mechanism,and catalyst system involved in plasma nitrogen *** from current research,it evaluates the economic feasibility of the DBD plasmaassisted ammonia synthesis technology,analyzes existing dilemmas and challenges,and provides insights and recommendations for the future of nonthermal plasma ammonia processes.

关键词： plasma catalysis nitrogen fixation ammonia synthesis hydrogen storage catalyst carbon neutralization

Allocation of Network Error Correction Flow on Disjoint Paths

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Tsinghua Science and Technology 2015年第2期20卷 182-187页

作者： Zhiqing xiao Yunzhou Li jing Wang the Department of Electronic Engineering Tsinghua University the Research Institute of Information Technology Tsinghua University

The diversity provided by disjoint paths can increase the survivability of communication networks. This paper considers the allocation of network error correction flow on a network that consists of disjoint paths from the source node to the destination node. Specifically, we propose an algorithm of allocating the path-flows to support the given rate with minimum cost. Our analysis shows that the asymptotic time complexity of this algorithm is linearithmic, and this algorithm is optimal in general

关键词： network survivability disjoint paths maximum distance separable codes network error correction

Color reproduction for noisy CFA data using directional cycle-spinning

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Journal of Systems Engineering and Electronics 2011年第3期22卷 528-533页

作者： Weiyu Yu jing Tian Yonghao xiao School of Electronic and Information Engineering South China University of TechnologyGuangzhou 510640P.R.China Provincial Key Laboratory for Computer Information Processing Technology School of Computer Science and TechnologySoochow UniversitySuzhou 215006P.R.China School of Electrical and Electronic Engineering Nanyang Technological UniversityNanyang Avenue 639798Singapore

This paper addresses color filter array（CFA） color reproduction problem where the aim is to utilize an image captured by the CFA to produce an image with full color ***,conventional subband synthesis based color reproduction techniques do not consider the noise during image acquisition and assume that the CFA data are *** tackle the noisy CFA data,a novel approach is proposed by inserting a subband denoising scheme into the conventional subband synthesis ***,conventional subband synthesis based techniques exploit the decimated wavelet transform that is not shift-invariant and could result in ringing artifacts in the *** alleviate these artifacts,the directional cycle-spinning（DCS） technique is ***,a new cycle-spinning pattern is proposed according to the sampling pattern of the Bayer CFA *** experiments are conducted to demonstrate that the proposed approach outperforms several approaches.

关键词： color filter array(CFA) cycle-spinning denoising.