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双重PCR区分检测花生黑腐病菌和花生基腐病菌

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中国油料作物学报 2024年第4期46卷 913-919页

作者：潘斐敖莉丝潘汝谦纪春艳华南农业大学植物保护学院广东广州510642

黑腐病和基腐病是威胁花生生产的重要病害。两种病害在田间发病症状十分相似,凭症状区分诊断困难。本研究利用calmodulin(cmdA)基因序列设计特异性引物,通过优化反应体系和反应条件,针对花生黑腐病菌和基腐病菌进行了双重PCR的区分检测... 详细信息

黑腐病和基腐病是威胁花生生产的重要病害。两种病害在田间发病症状十分相似,凭症状区分诊断困难。本研究利用calmodulin(cmdA)基因序列设计特异性引物,通过优化反应体系和反应条件,针对花生黑腐病菌和基腐病菌进行了双重PCR的区分检测。结果表明,在反应体系浓度为1.8×、引物浓度为0.2μmol/L、退火温度为62℃、反应循环数为37的条件下,可特异性地分别扩增出两条目的条带(274 bp和409 bp),检测灵敏限度为100 pg/μL。成功建立了可准确、快速区分检测花生黑腐病菌和花生基腐病菌的双重PCR,可为准确诊断和及时防控花生两种易混淆的病害提供科学的参考。

关键词：花生黑腐病菌基腐病菌双重PCR

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Application of A Fully Nonlinear Higher-Order Element Method for Modelling Three-Dimensional Wave Entry of A Cone

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China Ocean Engineering 2021年第6期35卷 814-827页

作者： YUAN Dong-chuang CHENG Yong ji chun-yan School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Fully nonlinear water entry of a cone into waves with gravity effect has been analyzed based on a three-dimensional(3D)higher-order boundary method(HOBEM).The total velocity potential at the initial time is divided into the incident and scattering *** the subsequent time steps,the solution of the velocity potential is defined as a whole through instantaneous boundary *** on the image theory,a modified Green function is applied to establish the integral equations so that only half of the calculation domain is considered and the seabed can be *** free surface elevation is tracked along a given azimuth plane in the polar coordinate system,while the horizontal motion of the water particle is updated by using a segment-spring analogy method,which redistributes nodes and maintains mesh connectivity according to linear *** auxiliary function is applied to solve the pressure distribution,instead of directly calculating time derivative of the velocity *** high accuracy of the present numerical method is achieved through a detailed convergence study and comparison with results in the *** are emphatically performed to examine the effects of gravity,wave nonlinearity,entry location,and oblique entry.

关键词： wave entry HOBEM time-domain simulation Green function segment-spring analogy method

Time-Domain Nonlinear Wave-Current Interaction with A Steep Wave Riser Considering Internal Flow Effect

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China Ocean Engineering 2021年第3期35卷 410-421页

作者： TANG Lian-yang CHENG Yong ji chun-yan School of naval architecture and ocean engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Nippon Kaiji Kyokai(China)Co. LtdShanghai 200336China

The nonlinear dynamic response induced by the wave-current interaction on a deepwater steep wave riser(SWR)is numerically investigated based on a three-dimensional(3 D)time-domain finite element method(FEM).The governing equation considering internal flow is established in the global coordinate *** whole SWR consists of three segments:the decline segment,buoyancy segment and hang-off segment,in which the buoyancy segment is wrapped by several buoyancy modules in the middle section,leading to the arch bend and sag bend.A Newmark-β iterative scheme is adopted for the accurate analysis to solve the governing equation and update the dynamic response at each time *** proposed method is verified through the published results for the dynamic response of steel catenary riser(SCR)and static configuration of steel lazy wave riser(SLWR).Simulations are executed to study the influence of wave height,current velocity/direction,internal flow density/velocity and top-end pressure on the tension,configuration and bending moment of the *** results indicate that the influence of the current on the configuration and mechanical behavior of the SWR is greater than that of the wave,especially in the middle *** increasing current velocity,the suspending height of the middle section drops,meanwhile,its bending moment decreases accordingly,but the tension increases *** a fixed external load,the increasing internal flow density induces the amplification of the tension at the hang-off segment and the mitigation at the decline segment,while the opposite trend occurs at the bending moment.

关键词： steep wave riser(SWR) nonlinear dynamic response wave-current interaction time-domain finite element method(FEM)

Nonlinear Analysis of Bidirectional Vortex-Induced Vibration of A Deepwater Steep Wave Riser Subjected to Oblique Currents

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China Ocean Engineering 2021年第6期35卷 852-865页

作者： CHENG Yong TANG Lian-yang ji chun-yan School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Nippon Kaiji Kyokai(China)Co. LtdShanghai 200336China

An improved three-dimensional(3D)time-domain couple model is established in this paper to simulate the bidirectional vortex-induced vibration(VIV)of a deepwater steep wave riser(SWR)subjected to oblique *** this model,the nonlinear motion equations of the riser are established in the global coordinate system based on the slender rod theory with the finite element *** der Pol equations are used to describe the lift forces induced by the x-and y-direction current components,*** coupled equations at each time step are solved by a Newmark-βiterative scheme for the SWR *** present model is verified by comparison with the published experimental results for a top-tension ***,a series of simulations are executed to determine the influences of the oblique angle/velocity of the current,different top-end positions and the length of the buoyancy segment on the VIV displacement,oscillating frequency as well as hydrodynamic coefficients of the *** results demonstrate that there exists a coupled resonant VIV corresponding to x-direction and y-direction,***,the effective frequency is almost identical between the vibrations at the hang-off segment along x and y *** addition of the buoyancy modules in the middle of the SWR has a beneficial impact on the lift force of three segments and simultaneously limits the VIV response,especially at the decline segment and the hang-off ***,the incident current direction significantly affects the motion trajectory of the SWR which mainly includes the fusiform and rectangle shapes.

关键词： steep wave riser(SWR) bidirectional vortex-induced vibration wake oscillator model time-domain finite element method(TDFEM)

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不同处理方式对鲜切马铃薯条保鲜效果研究

安徽农业科学 2024年第5期52卷 201-203,207页

作者：季春艳张云云贺荣刘艳红李双芳乔勤勤刘生杰阜阳师范大学信息工程学院安徽阜阳236037 阜阳师范大学生物与食品工程学院安徽阜阳236037

采用鲜切马铃薯条为主要原料,分别对其进行63℃热处理、护色剂浸泡处理、复合涂膜浸泡处理、乳酸链球菌素浸泡处理,以蒸馏水浸泡为对照组,置于4℃冰箱内低温保存3 d,每12 h测定失重率、褐变度、总酚含量、还原糖含量、淀粉含量等指标。... 详细信息

采用鲜切马铃薯条为主要原料,分别对其进行63℃热处理、护色剂浸泡处理、复合涂膜浸泡处理、乳酸链球菌素浸泡处理,以蒸馏水浸泡为对照组,置于4℃冰箱内低温保存3 d,每12 h测定失重率、褐变度、总酚含量、还原糖含量、淀粉含量等指标。结果表明:63℃热处理会加快鲜切马铃薯条褐变并较快失去食用价值,护色剂处理可减少褐变但对失重率影响较小,复合涂膜处理和乳酸链球菌素溶液处理均可抑制鲜切马铃薯条的褐变,减少失重率,降低淀粉向还原糖转变,减少总酚的损失。

关键词：鲜切马铃薯保鲜复合涂膜剂护色剂乳酸链球菌素

Wave Slamming on An OWSC Wave Energy Converter in Coupled Wave-Current Conditions with Variable-Depth Seabed

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China Ocean Engineering 2021年第5期35卷 646-661页

作者： CHENG Yong ji chun-yan YUAN Zhi-ming Atilla INCECIK School of naval architecture and ocean engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Naval Architecture Ocean and Marine Engineering DepartmentUniversity of StrathclydeGlasgowUnited Kingdom

Coastal wave energy resources have enormous exploitation potential due to shorter weather window,closer installation distance and lower maintenance ***,impact loads generated by depth variation from offshore to nearshore and wave-current interaction,may lead to a catastrophic damage or complete destruction to wave energy converters(WECs).This objective of this paper is to investigate slamming response of a coastal oscillating wave surge converter(OWSC)entering or leaving water *** on fully nonlinear potential flow theory,a time-domain wave-current-structure interaction model combined with higher-order boundary element method(HOBEM),is developed to analyze the coupled hydrodynamic *** variable-depth seabed is considered in the model to illustrate the shallow water effect on impact loads and free surface profiles in coastal zone.A domain decomposition approach is utilized to simulate the overlapping phenomenon generated by a jet falling into water under gravity *** a series of Lagrangian interpolation methods,the meshes on boundaries are rearranged to avoid the mismatch between element size on free surface and body *** present model is validated against the existing experimental and numerical *** are also provided for the effects of wave-current interaction and uneven local seabed on the slamming *** is found that the length of the splash jet increases for a following current and decreases for an opposing current,and that the slamming response of the OWSC device is sensitive to the geometric features of the uneven seabed.

关键词： wave-current interaction oscillating wave surge converter fully nonlinear potential flow theory slamming response higher-order boundary element method

Three-dimensional Modeling of Ore-forming Elements and Mineralization Prognosis for the Yechangping Mo Deposit,Henan Province,China

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 736-752页

作者： DING Gaoming ji Genyuan yan Guolong XU Yongzhong WANG Kunming XIAO chun WANG Quanle GUO Dongbao China National Administration of Coal Geology Beijing 100038China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesCAGSBeijing 100037China China Gold Group Geological Co. Ltd.Beijing 100011China China Gold Group ZhongYuan Mining Co. Ltd.SanmenxiaHenan 472000China Lanzhou Mineral Exploration Institute of Gansu Nonferrous Metal Geological Exploration Bureau Lanzhou 730046China

Three-dimensional geochemical modeling of ore-forming elements is crucial for predicting deep *** approach provides key information for the quantitative prediction of deep mineral localization,three-dimensional fine interpolation,analysis of spatial distribution patterns,and extraction of quantitative mineral-seeking *** Yechangping molybdenum(Mo)deposit is a significant and extensive porphyry-skarn deposit in the East Qinling-Dabie Mo polymetallic metallogenic belt at the southern margin of the North China *** borehole data on oreforming elements underpin deep geochemical *** methodology includes the following steps:(1)Threedimensional geological modeling of the deposit was established.(2)Correlation,cluster,and factor analyses post delineation of mineralization stages and determination of mineral generation sequence to identify(Cu,Pb,Zn,Ag)and(Mo,W,mfe)assemblages.(3)A three-dimensional geochemical block model was constructed for Mo,W,mfe,Cu,Zn,Pb,and Ag using the ordinary kriging method,and the variational function was developed.(4)Spatial distribution and enrichment characteristics analysis of ore-forming elements are performed to extract geological information,employing the variogram and w(Cu+Pb+Zn+Ag)/w(Mo+W)as predictive indicators.(5)Identifying the western,northwestern,and southwestern areas of the mine with limited mineralization potential,contrasted by the northeastern and southeastern areas favorable for mineral exploration.

关键词： 3D geochemical model ore-forming elements geostatistics deep mineralization prediction Yechangping Mo deposit

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

Oblique Wave-Induced Responses of A VLFS Edged with A Pair of Inclined Perforated Plates

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China Ocean Engineering 2018年第1期32卷 14-25页

作者： CHENG Yong ji chun-yan ZHAI Gang-jun Gaidai Oleg School of Naval Architecture and Ocean Engineering Jiangsu University of Science and Technology Deepwater Engineering Research Center Dalian University of Technology Centre for Ships and Ocean Structures Norwegian University of Science and Technology

This paper is concerned with the hydroelastic responses of a mat-like, rectangular very large floating structure(VLFS) edged with a pair of horizontal/inclined perforated anti-motion plates in the context of the direct coupling method. The updated Lagrangian formulae are applied to establish the equilibrium equations of the VLFS and the total potential formula is employed for fluids in the numerical model including the viscous effect of the perforated plates through the Darcy’s law. The hybrid finite element-boundary element(FE-BE) method is implemented to determine the response reduction of VLFS with attached perforated plates under various oblique incident ***, the numerical solutions are validated against a series of experimental tests. The effectiveness of the attached perforated plates in reducing the deflections of the VLFS can be significantly improved by selecting the proper design parameters such as the porous parameter, submergence depth, plate width and inclination angle for the given sea conditions.

关键词： very large floating structure(VLFS) anti-motion device hydroelastic response numerical analysis experiment