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A New Inversion-free Iterative Method for Solving the Nonlinear Matrix Equation and Its Application in Optimal Control
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作者 GAO Xiangyu XIE Weiwei ZHANG Lina 《应用数学》 北大核心 2026年第1期143-150,共8页
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ... In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method. 展开更多
关键词 Nonlinear matrix equation Maximal positive definite solution Inversion-free iterative method Optimal control
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Broadband ground motion simulation and analysis of a near-fault 3D basin-mountain coupling site based on the hybrid method
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作者 Liu Zhongxian Tang Kang +2 位作者 Li Chengcheng Yuan Xiaoming Zhang Hai 《Earthquake Engineering and Engineering Vibration》 2026年第1期87-110,共24页
This study presents an effective hybrid simulation approach for simulating broadband ground motion in complex near-fault locations.The approach utilizes a deterministic approach based on the spectral element method(SE... This study presents an effective hybrid simulation approach for simulating broadband ground motion in complex near-fault locations.The approach utilizes a deterministic approach based on the spectral element method(SEM),which is used to simulate low-frequency ground motion(f<1 Hz)by incorporating an innovative efficient discontinuous Galerkin(DG)method for grid division to accurately model basin sedimentary layers at reduced costs.It also introduces a comprehensive hybrid source model for high-frequency random scattering and a nonlinear analysis module for basin sedimentary layers.Deterministic outcomes are combined with modified three-dimensional stochastic finite fault method(3D-EXSIM)simulations of high-frequency ground motion(f>1 Hz).A fourth-order Butterworth filter with zero phase shift is employed for time-domain filtering of low-and high-frequency time series at a crossover frequency of 1 Hz,merging the low and high-frequency ground motions into a broadband time series.Taking an Ms 6.8 Luding earthquake,as an example,this hybrid method was used for a rapid and efficient simulation analysis of broadband ground motion in the region.The accuracy and efficiency of this hybrid method were verified through comparisons with actually observed station data and empirical attenuation curves.Deterministic method simulation results revealed the effects of mountainous topography,basin effects,nonlinear effects within the basin’s sedimentary layers,and a coupling interaction between the basin and the mountains.The findings are consistent with similar studies,showing that near-fault sedimentary basins significantly focus and amplify strong ground motion,and the soil’s nonlinear behavior in the basin influences ground motion to varying extents at different distances from the fault.The mountainous topography impacts the basin’s response to ground motion,leading to barrier effects.This research provides a scientific foundation for seismic zoning,urban planning,and seismic design in nearfault mountain basin regions. 展开更多
关键词 hybrid ground motion simulation method spectral element method three-dimensional stochastic finite fault method near-fault basin-mountain coupling effect basin effect nonlinear effect
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Healthcare professionals’perspectives on disclosure of diagnosis and related issues in childhood cancer:A mixed methods systematic review
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作者 Run Xie Xiaoyan Huang +4 位作者 Yiran Du Ying Gu Qiongfang Kang Hongsheng Wang Daqian Zhu 《International Journal of Nursing Sciences》 2026年第1期96-104,I0006,共10页
Objectives This review aimed to systematically synthesize the available research on the disclosure of diagnosis and related issues in childhood cancer from the perspectives of healthcare professionals,with the goal of... Objectives This review aimed to systematically synthesize the available research on the disclosure of diagnosis and related issues in childhood cancer from the perspectives of healthcare professionals,with the goal of informing the optimization of disclosure processes and meeting the communication needs of affected families.Methods In accordance with the Joanna Briggs Institute(JBI)methodology for mixed methods systematic reviews,the convergent segregated approach was used in this review.Articles were retrieved from 11 databases,including PubMed,Web of Science,CINAHL,CENTRAL,Embase,Ovid/Medline,PsycINFO,PsycArticles,Scopus,ERIC,and China National Knowledge Infrastructure(CNKI).The quality of the selected articles was assessed using the Mixed Method Appraisal Tool(MMAT).The review protocol was registered on PROSPERO(CRD42024542746).Results A total of 21 studies from 10 countries were included.Their methodological quality was generally medium to high,with MMAT scores ranging from 60%to 100%.The synthesis yielded three core themes:1)the spectrum of professional and societal attitudes toward disclosure;2)the dynamic practices of navigating disclosure amid uncertainty,including timing and environment,stakeholders,and content of disclosure;and 3)factors influencing disclosure,including children’s,parental,healthcare professionals’,and socio-cultural factors.Conclusions This review synthesized the perspectives and experiences of healthcare professionals regarding disclosure in childhood cancer,highlighting the complexity and multidimensional nature of this process in clinical practice.Future research should further investigate the experiences and needs of children and their parents,explore cultural variations in disclosure practices,develop context-appropriate assessment tools,and construct multidimensional intervention strategies to enhance the humanistic care and professional effectiveness of the disclosure process. 展开更多
关键词 Communication CANCER DISCLOSURE Healthcare professionals Mixed methods PEDIATRIC Systematic review
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Crushing evolution in pebble bed based on a novel method:a crushable DEM study
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作者 Jian Wang Ming‑Zhun Lei +4 位作者 Ming‑Zong Liu Qi‑Gang Wu Zi‑Cong Cai Kai‑Song Wang Hai‑Shun Deng 《Nuclear Science and Techniques》 2026年第1期212-224,共13页
In this paper,a novel method for investigating the particle-crushing behavior of breeding particles in a fusion blanket is proposed.The fractal theory and Weibull distribution are combined to establish a theoretical m... In this paper,a novel method for investigating the particle-crushing behavior of breeding particles in a fusion blanket is proposed.The fractal theory and Weibull distribution are combined to establish a theoretical model,and its validity was verified using a simple impact test.A crushable discrete element method(DEM)framework is built based on the previously established theoretical model.The tensile strength,which considers the fractal theory,size effect,and Weibull variation,was assigned to each generated particle.The assigned strength is then used for crush detection by comparing it with its maximum tensile stress.Mass conservation is ensured by inserting a series of sub-particles whose total mass was equal to the quality loss.Based on the crushable DEM framework,a numerical simulation of the crushing behavior of a pebble bed with hollow cylindrical geometry under a uniaxial compression test was performed.The results of this investigation showed that the particle withstands the external load by contact and sliding at the beginning of the compression process,and the results confirmed that crushing can be considered an important method of resisting the increasing external load.A relatively regular particle arrangement aids in resisting the load and reduces the occurrence of particle crushing.However,a limit exists to the promotion of resistance.When the strain increases beyond this limit,the distribution of the crushing position tends to be isotropic over the entire pebble bed.The theoretical model and crushable DEM framework provide a new method for exploring the pebble bed in a fusion reactor,considering particle crushing. 展开更多
关键词 Crushing behavior Granular material Discrete element method Pebble bed Fractal theory
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ANALYSIS OF A QUADRILATERAL EDGE ELEMENT METHOD FOR MAXWELL EQUATIONS
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作者 Zhijie DU Huoyuan DUAN Caihong WANG 《Acta Mathematica Scientia》 2026年第1期275-292,共18页
A new quadrilateral edge element method is proposed and analyzed for Maxwell equations.This proposed method is based on Duan-Liang quadrilateral element(Math.Comp.73(2004),pp.1–18).When applied to the eigenvalue prob... A new quadrilateral edge element method is proposed and analyzed for Maxwell equations.This proposed method is based on Duan-Liang quadrilateral element(Math.Comp.73(2004),pp.1–18).When applied to the eigenvalue problem,the method is spectral-correct and spurious-free.Stability and error estimates are obtained,including the interpolation error estimates and the error estimates between the finite element solution and the exact solution.The method is suitable for singular solution as well as smooth solution,and consequently,the method is valid for nonconvex domains which may have a number of reentrant corners.Of course,the method is suitable for arbitrary quadrilaterals(under the usual shape-regular condition). 展开更多
关键词 Maxwell equations finite element method quadrilateral mesh STABILITY error bound spectral approximation
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An improved open-top dynamic chambers method for measuring the exchange fluxes of N_(2)O,NO and NH_(3) from farmland
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作者 Minhang Tan Yining Hu +6 位作者 Yifei Song Zixuan Huang Yujing Mu Junfeng Liu Chenglong Zhang Pengfei Liu Yuanyuan Zhang 《Journal of Environmental Sciences》 2026年第1期535-545,共11页
The application of nitrogen fertilizers in agricultural fields can lead to the release of nitrogen-containing gases(NCGs),such as NO_(x),NH_(3) and N_(2)O,which can significantly impact regional atmospheric environmen... The application of nitrogen fertilizers in agricultural fields can lead to the release of nitrogen-containing gases(NCGs),such as NO_(x),NH_(3) and N_(2)O,which can significantly impact regional atmospheric environment and con-tribute to global climate change.However,there remain considerable research gaps in the accurate measurement of NCGs emissions from agricultural fields,hindering the development of effective emission reduction strategies.We improved an open-top dynamic chambers(OTDCs)system and evaluated the performance by comparing the measured and given fluxes of the NCGs.The results showed that the measured fluxes of NO,N_(2)O and NH_(3)were 1%,2%and 7%lower than the given fluxes,respectively.For the determination of NH_(3) concentration,we employed a stripping coil-ion chromatograph(SC-IC)analytical technique,which demonstrated an absorption efficiency for atmospheric NH_(3) exceeding 96.1%across sampling durations of 6 to 60 min.In the summer maize season,we utilized the OTDCs system to measure the exchange fluxes of NO,NH_(3),and N_(2)O from the soil in the North China Plain.Substantial emissions of NO,NH_(3) and N_(2)O were recorded following fertilization,with peaks of 107,309,1239 ng N/(m^(2)·s),respectively.Notably,significant NCGs emissions were observed following sus-tained heavy rainfall one month after fertilization,particularly with NH_(3) peak being 4.5 times higher than that observed immediately after fertilization.Our results demonstrate that the OTDCs system accurately reflects the emission characteristics of soil NCGs and meets the requirements for long-term and continuous flux observation. 展开更多
关键词 Open-top dynamic chambers Nitrogen-containing gases Soil emissions North China Plain method evaluation
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Centralized Circumcentered-Reflection Method for Solving the Convex Feasibility Problem in Sparse Signal Recovery
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作者 Chunmei LI Bangjun CHEN Xuefeng DUAN 《Journal of Mathematical Research with Applications》 2026年第1期119-133,共15页
Convex feasibility problems are widely used in image reconstruction, sparse signal recovery, and other areas. This paper is devoted to considering a class of convex feasibility problem arising from sparse signal recov... Convex feasibility problems are widely used in image reconstruction, sparse signal recovery, and other areas. This paper is devoted to considering a class of convex feasibility problem arising from sparse signal recovery. We first derive the projection formulas for a vector onto the feasible sets. The centralized circumcentered-reflection method is designed to solve the convex feasibility problem. Some numerical experiments demonstrate the feasibility and effectiveness of the proposed algorithm, showing superior performance compared to conventional alternating projection methods. 展开更多
关键词 convex feasibility problem centralized circumcentered-re ection method sparse signal recovery compressed sensing
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A new ground-motion scaling and record selection procedure for asymmetric-plan buildings using the 2DOF-modal pushover method
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作者 Hamid Hojaji Mohammad Sadegh Birzhandi Mohammad Mahdi Zafarani 《Earthquake Engineering and Engineering Vibration》 2026年第1期71-86,共16页
Advanced intensity measures(IMs)based on an inelastic deformation spectrum improved the evaluation of the median engineering demand parameters(EDPs)and reduced dispersion.In this regard,an optimized two-degreefreedom(... Advanced intensity measures(IMs)based on an inelastic deformation spectrum improved the evaluation of the median engineering demand parameters(EDPs)and reduced dispersion.In this regard,an optimized two-degreefreedom(2DOF)modal pushover-based scaling procedure(2DMPS)has been developed for a nonlinear dynamic analysis of asymmetric in-plan buildings.The 2DMPS procedure scales ground motions to approach close enough to a target value of the inelastic displacement of the first-mode inelastic 2DOF modal stick,extended for structures with significant contributions of higher modes.Further,4-,6-and 13-story RC SMRF buildings were selected for analyses using ground motion records scaled by the 2DMPS procedure,the modal pushover-based scaling method(MPS),and ASCE/SEI 7-16 scaling procedures.The median values of EDPs on scaled records closely matched the benchmark results.The bias in the EDP values due to the scaled records in every group regarding their median value was lower than the dispersion of the 21 unscaled records.These results generally demonstrate the accuracy and efficiency of the 2DMPS method.Additionally,the 2DOF modal stick’s inelastic response spectra are better suited for calculating seismic demands for one-way asymmetric-plan structures than the SDOF inelastic response spectra. 展开更多
关键词 intensity measure record selection asymmetric structures modal pushover method record scaling inelastic response spectra
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Precision and trueness of a method for determing antimony content in groundwater using hydride generation-atomic fluorescence spectrometry
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作者 Bing-bing Liu Lin Zhang Ke Li 《Journal of Groundwater Science and Engineering》 2026年第1期49-58,共10页
At present,there is currently a lack of unified standard methods for the determination of antimony content in groundwater in China.The precision and trueness of related detection technologies have not yet been systema... At present,there is currently a lack of unified standard methods for the determination of antimony content in groundwater in China.The precision and trueness of related detection technologies have not yet been systematically and quantitatively evaluated,which limits the effective implementation of environmental monitoring.In response to this key technical gap,this study aimed to establish a standardized method for determining antimony in groundwater using Hydride Generation–Atomic Fluorescence Spectrometry(HG-AFS).Ten laboratories participated in inter-laboratory collaborative tests,and the statistical analysis of the test data was carried out in strict accordance with the technical specifications of GB/T 6379.2—2004 and GB/T 6379.4—2006.The consistency and outliers of the data were tested by Mandel's h and k statistics,the Grubbs test and the Cochran test,and the outliers were removed to optimize the data,thereby significantly improving the reliability and accuracy.Based on the optimized data,parameters such as the repeatability limit(r),reproducibility limit(R),and method bias value(δ)were determined,and the trueness of the method was statistically evaluated.At the same time,precision-function relationships were established,and all results met the requirements.The results show that the lower the antimony content,the lower the repeatability limit(r)and reproducibility limit(R),indicating that the measurement error mainly originates from the detection limit of the method and instrument sensitivity.Therefore,improving the instrument sensitivity and reducing the detection limit are the keys to controlling the analytical error and improving precision.This study provides reliable data support and a solid technical foundation for the establishment and evaluation of standardized methods for the determination of antimony content in groundwater. 展开更多
关键词 Mandel's h and k statistics Grubbs test Cochran test Repeatability limit Reproducibility limit method bias value
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An improved stochastic finite-fault simulation method and its application to large magnitude thrust earthquakes
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作者 Ma Wanjun Xie Zhinan 《Earthquake Engineering and Engineering Vibration》 2026年第1期41-53,共13页
The stochastic extended finite-fault simulation method(EXSIM)is a widely used tool in seismological research,with applications in ground motion prediction and simulation,seismic hazard analysis,and engineering studies... The stochastic extended finite-fault simulation method(EXSIM)is a widely used tool in seismological research,with applications in ground motion prediction and simulation,seismic hazard analysis,and engineering studies.However,recent studies have revealed a significant limitation:EXSIM tends to overpredict ground motions in the low-to-intermediate frequency range,particularly for large thrust earthquakes that are often characterized by a double-corner-frequency source model.To address this issue and enhance simulation accuracy,this study introduces two key improvements:(1)a novel asperity-distributed stress-drop composite fault model and(2)a hybrid application of EXSIM with the composite fault model.The proposed method is validated through its application to the 2013 M_(w)6.7 Lushan earthquake that occurred in China and six thrust earthquakes with an M_(w)≥6.5 in Japan.By comparing the simulated ground motions with recorded data,the results demonstrate that the improved method achieves consistent accuracy across the high-and low-frequency spectrum(combined goodness-of-fit:CGOF<0.35).This study significantly broadens the applicability of stochastic finite-fault simulations,enabling more reliable predictions for a wider range of seismic scenarios,including complex thrust faulting events. 展开更多
关键词 stochastic finite-fault simulation method double-corner-frequency source model large-thrust earthquakes asperity-like distributed stress-drop compound faults hybrid application of EXSIM
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Microstructure control of AZ31 alloy by self-inoculation method for semisolid rheocasting 被引量:6
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作者 邢博 郝远 +2 位作者 李元东 马颖 陈体军 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第3期567-575,共9页
A novel rheocasting process, self-inoculation method (SIM), was developed for the microstructure control of semisolid wrought Mg alloy. This process involves mixing between liquid alloy and particles of solid alloy ... A novel rheocasting process, self-inoculation method (SIM), was developed for the microstructure control of semisolid wrought Mg alloy. This process involves mixing between liquid alloy and particles of solid alloy (self-inoculants), subsequently pouring the mixed melt into a special designed multi-stream fluid director. The primary phase with dendritic morphology in the conventionally cast AZ31 alloy has readily transformed into near spherical one in the slurry produced by SIM from melt treatment temperature between 690 ℃ and 710 ℃ and self-inoculants addition of 3%-7%. Achievement of the non-dendritic microstructure at the higher melt treatment temperature requires more self-inoculants addition or decreases in the slope angle of fluid director. Primary phase in the slurry thus produced has attained an ideally globular morphology after isothermal holding at 620 ℃ for 30 s. The increasing holding time leads to decrease of shape factor but the coarsening of particle size. The spheroidization and coarsening evolution process of solid particles during the isothermal holding were analyzed by Lifshitz-Slyozov-Wagner (LSW) theory. 展开更多
关键词 AZ31 alloy MICROSTRUCTURE semisolid rheocasting self-inoculation method
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Seedling Petri-dish inoculation method:A robust,easy-to-use and reliable assay for studying plant-Ralstonia solanacearum interactions 被引量:4
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作者 CAO Peng CHEN Jia-lan +6 位作者 LI Ning-ning ZHANG Shuang-xi WANG Rong-bo LI Ben-jin LIU Pei-qing AN Yu-yan ZHANG Mei-xiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第12期3709-3719,共11页
Ralstonia solanacearum causes a lethal bacterial wilt disease in many crops,leading to huge losses in crop production every year.Understanding of plant-R.solanacearum interactions will aid to develop efficient strateg... Ralstonia solanacearum causes a lethal bacterial wilt disease in many crops,leading to huge losses in crop production every year.Understanding of plant-R.solanacearum interactions will aid to develop efficient strategies to control the disease.As a soilborne pathogen,R.solanacearum naturally infects plants via roots.A huge limitation in studying plant-R.solanacearum interactions is the large variation of R.solanacearum infection assay due to the variable soil conditions and uneven inoculum exposure.Here,we developed a robust and reliable Petri-dish inoculation method which allows consistent and stable infection in young plant seedlings.This method is easy to use,takes about only 10 days from seed germination to the completion of inoculation assay,and requires less inoculum of bacteria as well as growth chamber space.We proved the efficacy of the seedling Petri-dish inoculation method by analyzing plant defense primed by molecular patterns,resistance of defense-related plant mutants,and virulence of R.solanacearum mutants.Furthermore,we demonstrated that the seedling Petri-dish inoculation method can be applied to other host plants such as tobacco and has great potential for high-throughput screening of resistant plant germplasms to bacterial wilt in the future. 展开更多
关键词 bacterial wilt Ralstonia solanacearum Petri-dish inoculation method VIRULENCE resistance defense priming
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Influence of different inoculation methods on the evaluation of the resistance to rice sheath blight(Rhizoctonia solani Kuhn) 被引量:6
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作者 PAN Xuebiao CHEN Zongxiang XU Jingyou TONG Yunhui WANG Zibin PAN Xingyuan Dept of Agro of Agri Coll,Yangzhou Univ,Yangzhou 225009,China 《Chinese Rice Research Newsletter》 1998年第2期7-8,共2页
To establish a standard system for geneticstudies on sheath blight resistance, a field testwas conducted at the experimental farm ofYangzhou University to compare several pro-cedures for inoculating rice plants with R... To establish a standard system for geneticstudies on sheath blight resistance, a field testwas conducted at the experimental farm ofYangzhou University to compare several pro-cedures for inoculating rice plants with R.solani Kuhn (RH9). The varieties used wereJasmine 85, Teqing (resistant or moderatelyresistant), and Lemont (susceptible). They 展开更多
关键词 Influence of different inoculation methods on the evaluation of the resistance to rice sheath blight Rhizoctonia solani Kuhn
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Breeding for FHB Resistance via Fusarium Damaged Kernels and Deoxynivalenol Accumulation as Well as Inoculation Methods in Winter Wheat 被引量:2
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作者 Akos Mesterházy Szabolcs Lehoczki-Krsjak +3 位作者 Mónika Varga ágnes Szabó-Hevér Beata Tóth Marc Lemmens 《Agricultural Sciences》 2015年第9期970-1002,共33页
FHB is one of the most destructive diseases of wheat. Resistance testing depends strongly on inoculation methods, and on measured traits. Therefore a four-year (2009-2012) study was performed using spray inoculation +... FHB is one of the most destructive diseases of wheat. Resistance testing depends strongly on inoculation methods, and on measured traits. Therefore a four-year (2009-2012) study was performed using spray inoculation + polyethylene (PE) bag cover, spray inoculation + mist irrigation, and spawn method supported by mist irrigation on 40 genotypes, 20 from Hungary and 20 from IFA Tulln, Austria. Each year four isolates were used in artificial inoculations except the spawn method where stalk debris served the inoculum. Visual Fusarium head blight (FHB) scores, Fusarium damaged kernels (FDK) and deoxynivalenol (DON) contamination were checked. 7680 FHB and FDK, as well as 3840 DON analyses served as the background for the statistical evaluation. The most reliable method used was the spray + polyethylene (PE) bag;the other two were significantly poorer being valid for all traits. The FHB scores were the least reliable, whereas the FDK was much more consequent and the DON gave the best results. The FDK gave much better predictions for DON contamination than FHB. The cultivars responses correlated well at different epidemic severities. The presence of the kernel resistance was confirmed and a new trait as extra kernel susceptibility was described. Presence of DON resistance was confirmed again, and extra DON susceptibility was described as a new trait. DON performance varied on the most sensitive cultivar between 0.32 and 143 mg/kg (mean 17.52 mg/kg) and on the most resistant genotype between 0.00 and 18.19 mg/kg (mean 1.87 mg/kg). Correlations between stability and resistance level are r = 0.85 for FHB, 0.78 for FDK, and 0.88 for DON, all at a significance level of p = 0.001. The very close correlation between FDK and DON contamination (r = 0.81, p = 0.001) proves that control of DON contamination needs appropriate resistance. In the breeding program evaluation of FDK is the most important, and then DON will be decided. Variety registration must be updated;otherwise no improvement on the field will occur. 展开更多
关键词 FHB RESISTANCE KERNEL RESISTANCE KERNEL SUSCEPTIBILITY DON RESISTANCE DON SUSCEPTIBILITY inoculation Techniques BREEDING Aspects
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Microstructure characteristics and solidification behavior of wrought aluminum alloy 2024 rheo-diecast with self-inoculation method 被引量:15
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作者 Li Yanlei Li Yuandong +1 位作者 Li Chun Wu Huihui 《China Foundry》 SCIE CAS 2012年第4期328-336,共9页
One important problem in casting wrought aluminum alloys is the high tendency to the formation of hot tears in the solidification process.By using semi-solid metal(SSM) processing,the hot tearing tendency of alloys ca... One important problem in casting wrought aluminum alloys is the high tendency to the formation of hot tears in the solidification process.By using semi-solid metal(SSM) processing,the hot tearing tendency of alloys can be minimized during casting.In the present research,the semi-solid slurry of wrought aluminum alloy 2024 was firstly prepared with a novel self-inoculation method(SIM),and then the microstructure characteristics of the semi-solid slurry and the rheo-diecastings cast with the semi-solid slurry were investigated.The results indicate that finer and more uniform globular primary α-Al particles can be obtained when the semi-solid slurry are isothermally held for a short period within the semi-solid temperature range,and the primary α-Al particles without entrapped liquid are uniformly fine,globular grains in the rheo-diecastings.The holding temperature and time affect the solid fraction,particle size,and shape factor.After the semi-solid slurry is held at 625 ℃ for 3 min and 5 min,the optimal values for the average equivalent diameter are 70.80 μm and 74.15 μm,and for the shape factor are 1.32 and 1.42,respectively.The solidification process of the rheo-diecastings is composed of the following two distinct stages:primary solidification process and secondary solidification process.The secondary solidification process consists further of the following three stages:(1) direct growth of secondary primary(α 2) phase from the surface of the primary α-Al phase particles without re-nucleation,(2) independent nucleation and growth of α 3 phase from the residual liquid,and(3) eutectic reaction at the end. 展开更多
关键词 self-inoculation method wrought aluminum alloy 2024 solidification behavior secondary solidification
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Effect of Different Inoculation Methods on Pathogenicity of Fusarium proliferatum to Alfalfa
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作者 Yinghua LUO Mengteng LI +2 位作者 Congyu LI Chenghao JIN Xiangping LIU 《Asian Agricultural Research》 2020年第7期64-68,共5页
[Objectives]To find out the suitable inoculation method for Fusarium proliferatum.[Methods]Longmu 801 and TG4 were inoculated with rice grain-based inoculum at the bud and seedling stages and with root irrigation at t... [Objectives]To find out the suitable inoculation method for Fusarium proliferatum.[Methods]Longmu 801 and TG4 were inoculated with rice grain-based inoculum at the bud and seedling stages and with root irrigation at the seedling stage,respectively,and then,the plant height,aboveground biomass,underground biomass,incidence rate and disease index of the alfalfa were determined to conduct comprehensive resistance evaluation.[Results]There was obvious difference in disease resistance between the two alfalfa varieties.Among the three inoculation methods,the relative plant height,relative aboveground biomass and relative underground biomass of Longmu 801 differed insignificantly(P>0.05),all around 100.There were significant differences in TG4 among different inoculation methods(P<0.05).The incidence rates and disease indices of Longmu 801 and TG4 inoculated with rice grain-based inoculum at the bud stage were the highest,and their incidence rates and disease indices were 73.3%and 100%,and 40 and 60,respectively,significantly higher than those under the other two inoculation methods.The incidence rates and disease indices of Longmu 801 and TG4 inoculated with rice grain-based inoculum at the seedling stage were the lowest,and their incidence rates and disease indices were 0%and 13.30%,and 0 and 5.33,respectively,significantly lower than those under the other two inoculation methods.[Conclusions]The inoculation time and inoculation method of the pathogen both affect the inoculation effect.Among the three inoculation methods,the inoculation with rice grain-based inoculum at the bud stage is the most pathogenic to alfalfa seedlings,and can be popularized in the resistance evaluation of alfalfa to root diseases. 展开更多
关键词 ALFALFA Root rot Fusarium proliferatum inoculation method Disease resistance
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Microstructure of partially remelted billet of AM60 alloy prepared with self-inoculation method 被引量:4
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作者 邢博 李元东 +2 位作者 马颖 陈体军 郝远 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第9期1622-1629,共8页
The billets of AM60 alloy, prepared with self-inoculation method, were partially remelted into semisolid state. Effects of process parameters on remelting microstructure of semisolid billet were investigated. Experime... The billets of AM60 alloy, prepared with self-inoculation method, were partially remelted into semisolid state. Effects of process parameters on remelting microstructure of semisolid billet were investigated. Experimental results show that the solid particles obtained with self-inoculation method are in smaller grain size and globular shape after partial remelting, compared with those prepared with other casting methods. In the optimized process conditions, the average size of solid particles of partially remelted billet is 65 μm, and the shape factor is 1.12. The process parameters, i.e. pouting temperature, addition amount of self-inoculants, and the slope angle of multi-stream mixing cooling chalmel have influence on the microstructure of partially remelted billet. The optimized temperature is from 680 ℃ to 700 ℃, addition amount of self-inoculants is between 5% and 7% (mass fraction), slope angle of multi-stream mixing cooling channel is between 30° and 45°, with which the dendritic microstructure of as-cast billet can be avoided, and the size of solid particles ofremelted billet is reduced. 展开更多
关键词 AM60 Alloy self-inoculation method semisolid process partial remelting process parameters
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Effects of novel self-inoculation method on microstructure of AM60 alloy 被引量:5
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作者 Xing Bo Li Yuandong +1 位作者 Ma Ying Hao Yuan 《China Foundry》 SCIE CAS 2011年第1期121-126,共6页
A novel cast processing method,self-inoculation method (SIM),was proposed.The process involves the addition of self-inoculant to melt,then pouring the melt to a mould through a multi-stream mixing cooling channel.In t... A novel cast processing method,self-inoculation method (SIM),was proposed.The process involves the addition of self-inoculant to melt,then pouring the melt to a mould through a multi-stream mixing cooling channel.In this paper,the process parameters were investigated.Results indicate that the melt treatment temperature,the amount of self-inoculant added,and the slope angle of the cooling channel are the key factors for SIM process.The optimized parameters are that the melt treatment temperature is between 680 and 700°C;the addition of self-inoculant is between 5wt.% and 7wt.%;and the slope angle of the cooling channel is between 30° and 45°.Further analysis reveals that SIM changes the solidification microstructure of slurry by controlling the nucleation and growth of the primary phase in the melt. 展开更多
关键词 AM60 alloy self-inoculation method multi-stream mixing cooling channel nucleation and growth
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Solidification behavior and rheo-diecasting microstructure of A356 aluminum alloy prepared by self-inoculation method 被引量:3
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作者 Ming Li Yuan-dong Li +2 位作者 Xiao-feng Huang Chi Cao Ying Ma 《China Foundry》 SCIE 2017年第1期1-9,共9页
Semisolid slurry of A356 aluminum alloy was prepared by self-inoculation method, and the microstructure and solidification behavior during rheo-diecasting process were investigated. The results indicate that the semis... Semisolid slurry of A356 aluminum alloy was prepared by self-inoculation method, and the microstructure and solidification behavior during rheo-diecasting process were investigated. The results indicate that the semisolid slurry of A356 aluminum alloy can be prepared by self-inoculation method at 600℃. Primary a-AI particles with fine and spherical morphologies are uniformly distributed when the isothermal holding time of slurry is 3 min. Liquid phase segregation occurs during rheo-diecasting process of semisolid slurry and the primary particles (α1) show obvious plastic deformation in the area of high stress and low cooling rate. A small amount of dendrites resulting from the relatively low temperature of the shot chamber at the initial stage of secondary solidification are fragmented as they pass through the in-gate during the mould filling process. The amount of dendrite fragments decreases with the increase of filling distance. During the solidification process of the remaining liquid, the nucleation rate of secondary particles (α2) increases with the increase of cooling rate, and the content of Si in secondary particles (α2) are larger than primary particles (α1). With the increase of cooling rate, the content of Si in secondary particles (α2) gradually increases. The morphologies of eutectic Si in different parts of die casting are noticeably different. The low cooling rate in the first filling positions leads to coarse eutectic structures, while the high cooling rate in the post filling positions promotes small and compact eutectic structures. 展开更多
关键词 SEMISOLID self-inoculation method secondary solidification dendrite fragments primary particles eutectic structure
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Effect of Tree Species,Inoculation Amount and Methods on Mycellium Growth and Sclerotia Formation of Poria cocos Wolf
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作者 He Duck Lee Jong Il Ju ( ChungNam Provincial R. D. A Taejon, 305 - 313, Korea)Sang Yong Park ( S. M. ] Research Institute, 3042-32 Dae Myung 4 Dong, Nam- Ku, Taeku, Korea) 《吉林农业大学学报》 CAS CSCD 北大核心 1998年第S1期144-144,共1页
When medical mushroom, Poria cocos, is cultured, inoculation methods of spawn is cross slice inoculation for which the both sides of pine tree was peel and spawn of P. cocos was inoculated.However, this methods requir... When medical mushroom, Poria cocos, is cultured, inoculation methods of spawn is cross slice inoculation for which the both sides of pine tree was peel and spawn of P. cocos was inoculated.However, this methods requires lots of inoculation amount. This study was carried out to improve the culturing method of P. cocos;1. A good growth of P. cocos was observed in MCM (mushroom complete medium), showing proper mycelia growth and density.2. In inoculation amount, conventional method (cross slice inoculation) requires 20 bottles spawn. In contrast, short log method required 8 bottles of spawn and drilling inoculation method 2-3 bottles, which could save by 60% and 85%-90%, respectively.3. In the selection of tree species, pine and larch had better condition for spawn culture and sclerotia formation condition. In the terms of yield, pine was 33.7 kg/3. 3m2.4. In the yield of pine, conventional method was 23. 4 kg/3. 3m2, drilling inoculation 29. 4 kg/3.3m2, short log inoculation 31.7 kg/3. 3m2. Therefore drilling inoculation could increase by 25 % and short log inoculation 35 % . In the addition, management cost was also saved.5. The cost for inoculation spawn at the conventional method was 41 000 Won per unit area 3.3 m2. Drill inoculation 21 000 Won and short log inoculation 31 000 Won. Therefore the cost was lower at drill inoculation and short log inoculation by 49% and 25%, respectively, than conventional method. 展开更多
关键词 TREE SPECIES mycellium inoculation
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