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Qualitative Analysis of a Diffusive Predator-prey Model with Nonlcoal Fear Effect
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作者 Shen Zhongyuan Zhang Xuebing Li Shunjie 《数学理论与应用》 2024年第3期67-82,共16页
In this paper,we establish a delayed predator-prey model with nonlocal fear effect.Firstly,the existence,uniqueness,and persistence of solutions of the model are studied.Then,the local stability,Turing bifurcation,and... In this paper,we establish a delayed predator-prey model with nonlocal fear effect.Firstly,the existence,uniqueness,and persistence of solutions of the model are studied.Then,the local stability,Turing bifurcation,and Hopf bifurcation of the constant equilibrium state are analyzed by examining the characteristic equation.The global asymptotic stability of the positive equilibrium point is investigated using the Lyapunov function method.Finally,the correctness of the theoretical analysis results is verified through numerical simulations. 展开更多
关键词 Delay Nonlocal fear effect Global stability Hopf bifurcation
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The Limit Distribution of Stochastic Evolution Equations Driven by-Stable Non-Gaussian Noise
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作者 ZHAI Likai FU Hongbo 《应用数学》 北大核心 2024年第4期1180-1194,共15页
We study the distribution limit of a class of stochastic evolution equation driven by an additive-stable Non-Gaussian process in the case of α∈(1,2).We prove that,under suitable conditions,the law of the solution co... We study the distribution limit of a class of stochastic evolution equation driven by an additive-stable Non-Gaussian process in the case of α∈(1,2).We prove that,under suitable conditions,the law of the solution converges weakly to the law of a stochastic evolution equation with an additive Gaussian process. 展开更多
关键词 Stochastic evolution equation α-stable Non-Gaussian process DISTRIBUTION
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High-resolution reconstruction of the ablative RT instability flowfield via convolutional neural networks
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作者 Xia Zhiyang Kuang Yuanyuan +1 位作者 Lu Yan Yang Ming 《强激光与粒子束》 CAS CSCD 北大核心 2024年第12期42-49,共8页
High-resolution flow field data has important applications in meteorology,aerospace engineering,high-energy physics and other fields.Experiments and numerical simulations are two main ways to obtain high-resolution fl... High-resolution flow field data has important applications in meteorology,aerospace engineering,high-energy physics and other fields.Experiments and numerical simulations are two main ways to obtain high-resolution flow field data,while the high experiment cost and computing resources for simulation hinder the specificanalysis of flow field evolution.With the development of deep learning technology,convolutional neural networks areused to achieve high-resolution reconstruction of the flow field.In this paper,an ordinary convolutional neuralnetwork and a multi-time-path convolutional neural network are established for the ablative Rayleigh-Taylorinstability.These two methods can reconstruct the high-resolution flow field in just a few seconds,and further greatlyenrich the application of high-resolution reconstruction technology in fluid instability.Compared with the ordinaryconvolutional neural network,the multi-time-path convolutional neural network model has smaller error and canrestore more details of the flow field.The influence of low-resolution flow field data obtained by the two poolingmethods on the convolutional neural networks model is also discussed. 展开更多
关键词 convolutional neural networks the ablative Rayleigh-Taylor instability high-resolutionreconstruction multi-time-path pooling
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The influences of canopy temperature measuring on the derived crop water stress index
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作者 WANG Hongxi LI Fei +4 位作者 SHEN Hongtao LI Mengyu YIN Gongchao FANG Qin SHAO Liwei 《中国生态农业学报(中英文)》 CAS CSCD 北大核心 2024年第9期1503-1519,共17页
Crop water stress index(CWSI)is widely used for efficient irrigation management.Precise canopy temperature(T_(c))measurement is necessary to derive a reliable CWSI.The objective of this research was to investigate the... Crop water stress index(CWSI)is widely used for efficient irrigation management.Precise canopy temperature(T_(c))measurement is necessary to derive a reliable CWSI.The objective of this research was to investigate the influences of atmospheric conditions,settled height,view angle of infrared thermography,and investigating time of temperature measuring on the performance of the CWSI.Three irrigation treatments were used to create different soil water conditions during the 2020-2021 and 2021-2022 winter wheat-growing seasons.The CWSI was calculated using the CWSI-E(an empirical approach)and CWSI-T(a theoretical approach)based on the T_(c).Weather conditions were recorded continuously throughout the experimental period.The results showed that atmospheric conditions influenced the estimation of the CWSI;when the vapor pressure deficit(VPD)was>2000 Pa,the estimated CWSI was related to soil water conditions.The height of the installed infrared thermograph influenced the T_(c)values,and the differences among the T_(c)values measured at height of 3,5,and 10 m was smaller in the afternoon than in the morning.However,the lens of the thermometer facing south recorded a higher T_(c)than those facing east or north,especially at a low height,indicating that the direction of the thermometer had a significant influence on T_(c).There was a large variation in CWSI derived at different times of the day,and the midday measurements(12:00-15:00)were the most reliable for estimating CWSI.Negative linear relationships were found between the transpiration rate and CWSI-E(R^(2)of 0.3646-0.5725)and CWSI-T(R^(2)of 0.5407-0.7213).The relations between fraction of available soil water(FASW)with CWSI-T was higher than that with CWSI-E,indicating CWSI-T was more accurate for predicting crop water status.In addition,The R^(2)between CWSI-T and FASW at 14:00 was higher than that at other times,indicating that 14:00 was the optimal time for using the CWSI for crop water status monitoring.Relative higher yield of winter wheat was obtained with average seasonal values of CWSI-E and CWSI-T around 0.23 and 0.25-0.26,respectively.The CWSI-E values were more easily influenced by meteorological factors and the timing of the measurements,and using the theoretical approach to derive the CWSI was recommended for precise irrigation water management. 展开更多
关键词 Canopy temperature Measuring time Measuring height and direction Crop water stress index
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Interfacial Modification of NiO_(x)by Self-assembled Monolayer for Efficient and Stable Inverted Perovskite Solar Cells 被引量:1
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作者 Xin Yu Yandong Wang +5 位作者 Liufei Li Shantao Zhang Shuang Gao Mao Liang Wen-Hua Zhang Shangfeng Yang 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第4期553-562,I0080-I0091,I0095,共23页
NiO_(x)as a hole transport material for inverted perovskite solar cells has received great attention owing to its high transparency,low fabrication temperature,and superior stability.However,the mismatched energy leve... NiO_(x)as a hole transport material for inverted perovskite solar cells has received great attention owing to its high transparency,low fabrication temperature,and superior stability.However,the mismatched energy levels and possible redox reactions at the NiO_(x)/perovskite interface severely limit the performance of NiO_(x) based inverted perovskite solar cells.Herein,we introduce a p-type self-assembled monolayer between NiO_(x)and perovskite layers to modify the interface and block the undesirable redox reaction between perovskite and NiO_(x)The selfassembled monolayer molecules all contain phosphoric acid function groups,which can be anchored onto the NiOr surface and passivate the surface defect.Moreover,the introduction of self-assembled monolayers can regulate the energy level structure of NiO_(x),reduce the interfacial band energy offset,and hence promote the hole transport from perovskite to NiO_(x)layer.Consequently,the device performance is significantly enhanced in terms of both power conversion efficiency and stability. 展开更多
关键词 Perovskite solar cell NiO_(x) Self-assembled monolayer Interfacial engineering Stability
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Effect of TiB_(2)Nanoparticles on Microstructure and Mechanical Properties of Ni_(60)Cr_(21)Fe_(19)Alloy in Rapid Directional Solidification Process:Molecular Dynamics Study
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作者 WANG Jin JIANG Wugui HU Chenxi 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第5期575-588,共14页
Molecular dynamics(MD)simulations are employed to delve into the multifaceted effects of TiB2 nanoparticles on the intricate grain refinement mechanism,microstructural evolution,and tensile performance of Inconel 718 ... Molecular dynamics(MD)simulations are employed to delve into the multifaceted effects of TiB2 nanoparticles on the intricate grain refinement mechanism,microstructural evolution,and tensile performance of Inconel 718 superalloys during the rapid directional solidification.Specifically,the study focuses on elucidating the role of TiB2 nanoparticles in augmenting the nucleation rate during the rapid directional solidification process of Ni60Cr21Fe19 alloy system.Furthermore,subsequent tensile simulations are conducted to comprehensively evaluate the anisotropic behavior of tensile properties within the solidified microstructures.The MD results reveal that the incorporation of TiB₂nanoparticles during the rapid directional solidification of the Ni_(60)Cr_(21)Fe_(19)significantly enhances the average nucleation rate,escalating it from 1.27×10^(34)m^(-3)·s^(-1)to 2.55×10^(34)m^(-3)·s^(-1).Notably,within the face centered cube(FCC)structure,Ni atoms exhibit pronounced compositional segregation,and the solidified alloy maintains an exceptionally high dislocation density reaching up to 10^(16)m^(-2).Crucially,the rapid directional solidification process imparts a distinct microstructural anisotropy,leading to a notable disparity in tensile strength.Specifically,the tensile strength along the solidification direction is markedly superior to that perpendicular to it.This disparity arises from different deformation mechanisms under varying loading orientations.Tensile stress perpendicular to the solidification direction encourages the formation of smooth and organized mechanical twins.These twins act as slip planes,enhancing dislocation mobility and thereby improving stress relaxation and dispersion.Moreover,the results underscore the profound strengthening effect of TiB2 nanoparticles,particularly in enhancing the tensile strength along the rapid directional solidification direction. 展开更多
关键词 TiB_(2)nanoparticle rapid directional solidification microstructure evolution molecular dynamics
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法家实用实践思想论 被引量:1
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作者 许建良 《武陵学刊》 2012年第3期21-27,共7页
法家的实用是一个系统论的视野,它不仅把实用设计为道德的理论目标,而且精细运思了实用的实践世界。实用的驱动需要定分尤其是确立公私之分。在动态的层面,堵塞私门、私便是抑制人性趋利特点肆意活动的需要;这不是大公无私,而是在保证&q... 法家的实用是一个系统论的视野,它不仅把实用设计为道德的理论目标,而且精细运思了实用的实践世界。实用的驱动需要定分尤其是确立公私之分。在动态的层面,堵塞私门、私便是抑制人性趋利特点肆意活动的需要;这不是大公无私,而是在保证"私作"权利条件下的行为;在社会的层面,按能授事、循名而督实最为重要,实用实践的持久力来源于赏罚。实用是俭约的基础,而实用的源头在老子。在已经进入不得不实行俭约之道的今天,法家的实用思想具有积极的价值和意义。 展开更多
关键词 法家 定分 实用 实功 俭约
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人民法庭土地资源配置过程中的阻滞因素及现实进路——以S省H市48处人民法庭土地资源配置情况为研究样本 被引量:1
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作者 田源 梁坤 《中国不动产法研究》 2016年第1期15-27,共13页
引言人民法庭是人民法院基层纠纷化解职能发挥的重要平台,肩负着在农村地区定分止争的司法职责。~①截至2013年年底,全国共有10162个人民法庭,2006~2013年间共审结各类案件1929.5万件,占同期全国法院办案数的23,7%。~②最高人民法院院... 引言人民法庭是人民法院基层纠纷化解职能发挥的重要平台,肩负着在农村地区定分止争的司法职责。~①截至2013年年底,全国共有10162个人民法庭,2006~2013年间共审结各类案件1929.5万件,占同期全国法院办案数的23,7%。~②最高人民法院院长周强在第三次全国人民法庭工作会议上强调:'人民法庭是基础中的基础,推进司法改革要从人民法庭改起,把法庭作为改革的试验田。 展开更多
关键词 定分 司法 物质 止争 全国 土地 资源配置
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先秦法家的监察思想浅探 被引量:2
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作者 陈谦 《西北大学学报(哲学社会科学版)》 CSSCI 北大核心 2005年第6期73-76,共4页
在先秦思想家中,以韩非与商鞅为代表的法家最早并且较全面地提出了监察思想。通过对法家著作的阅读、清理,可以发现他们在监察目的、监察原则及监察手段等方面多有论述。先秦法家的监察思想,是以“势”、“法”、“术”为中心展开的,并... 在先秦思想家中,以韩非与商鞅为代表的法家最早并且较全面地提出了监察思想。通过对法家著作的阅读、清理,可以发现他们在监察目的、监察原则及监察手段等方面多有论述。先秦法家的监察思想,是以“势”、“法”、“术”为中心展开的,并且强调“法术”在监察活动中的意义,对后世的监察活动与监察制度产生了重大影响。以韩非为代表的“势不两立”的矛盾观和对道家“虚静无为”的处世哲学的转化,是先秦法家监察思想重要的理论基础。 展开更多
关键词 先秦法家 监察思想 循名责实 定分 韩非
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A GIS-based Study on Suitability Estimation of Tea Cultivation in Qimen County 被引量:11
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作者 叶寅 何方 +3 位作者 张学英 宫志锋 吕莎莎 方亮 《Agricultural Science & Technology》 CAS 2011年第1期149-152,共4页
On the basis of data from Soil Test and Formula Fertilization project in Qimen county,we employed Geographic Information System Software ArcGIS 9.2 and CLRMIS(Cultivated Land Resource Management Information System at... On the basis of data from Soil Test and Formula Fertilization project in Qimen county,we employed Geographic Information System Software ArcGIS 9.2 and CLRMIS(Cultivated Land Resource Management Information System at County Scale) to establish region-specific estimation index system for tea cultivation in Qimen County by determining the estimation units,and carried out quantitative estimation analysis on tea cultivation there via comprehensive evaluation indices for natural elements of cultivated land.The results showed that the highly suitable,suitable,reluctantly suitable and unsuitable acreages are 5 665.8,8 327.1,8 415.9 and 11 979.9 hm2 respectively,accounting for 24.0%,35.3%,35.7% and 5.1% of the total acreage of cultivated land.These results would facilitate the production of high yield and quality tea in Qimen County. 展开更多
关键词 Tea planting suitability Cultivated land GIS Quantitative assessment
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Identification of a Sex-Associated RAPD Marker in Ginkgo biloba 被引量:13
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作者 姜凌 尤瑞麟 +1 位作者 李懋学 时晨 《Acta Botanica Sinica》 CSCD 2003年第6期742-747,共6页
The random amplified polymorphic DNA (RAPD) technique was used to amplify DNA fragment, aiming at finding markers linked to the sex determination in Ginkgo biloba L. One thousand and two hundred random decamers had be... The random amplified polymorphic DNA (RAPD) technique was used to amplify DNA fragment, aiming at finding markers linked to the sex determination in Ginkgo biloba L. One thousand and two hundred random decamers had been screened. Of the 8 372 RAPD bands, only a 682 bp RAPD marker generated by a primer (S1478) of random decamer sequence, named S1478-682, was found to be associated with the male plants. This marker was present in all male plants and absent in all female plants. Ginkgo trees collected in both Beijing and Shenyang, China were tested using primer S1478. Positive results were obtained, suggesting S1478-682 could be utilized as a reliable RAPD marker to detect the sexuality of Ginkgo. 展开更多
关键词 Ginkgo biloba sex determination RAPD
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Chromosome Location of the Male-sterility and Yellow Seedling Gene in Line 1066A of Foxtail Millet 被引量:10
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作者 王润奇 高俊华 +3 位作者 毛丽萍 杜瑞恒 刁现民 孙敬三 《Acta Botanica Sinica》 CSCD 2002年第10期1209-1212,共4页
Using foxtail millet (Setaria italica (L.) Beauv.) male-sterile line 1066A as female parent and Yugu 1 primary trisomic series (1 - 7) and tetrasomics 8, 9 as male parents, chromosome location of gene for male-sterili... Using foxtail millet (Setaria italica (L.) Beauv.) male-sterile line 1066A as female parent and Yugu 1 primary trisomic series (1 - 7) and tetrasomics 8, 9 as male parents, chromosome location of gene for male-sterility and yellow seedling in line 1066A was studied by primary trisomic analysis. The plants of F-1 generation of trisomics 2 - 9 were obtained by crossing with a great many plants of 1066A. F-1 generation of trisomics was similar to their male parent in morphologic characters, the color of their seedling was green, and pollen was partially fertile. The segregation ratio of fertility to sterility is 3:1 in F-2 generation of trisomics 2, 3, 4, 5, 7, 8 and 9; and 14:1 only in F-2 generation of trisomic 6 (chi(0.05)(2) = 0.012). The segregation ratio of green seedling to yellow seedling is 12:1 only in F-2 generation of trisomic 7 (chi(0.05)(2) = 0.31), but in other cases, this ratio is 3:1. The results indicated that the male-sterility gene was located on chromosome 6, and the gene for yellow seedling was monogenic recessive and located on chromosome 7. The rate of trisomics transmission by pollen was tested, trisomics 8 and 9 were the highest in rates of trisomics transmission and followed by trisomics 6 and 4. 展开更多
关键词 Setaria italica MALE-STERILE yellow seedling primary trisomic analysis chromosome location
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Extraction Storage and Qualitative Analysis of Free Radicals Scavenging Substances from Sweet Potato Leaves 被引量:9
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作者 王友升 董银卯 +1 位作者 宋彦 黑维俭 《Agricultural Science & Technology》 CAS 2008年第2期1-5,9,共6页
[ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging sub... [ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging substances from sweet potato leaves were optimized by orthogonal test and the bioactive components in extracts were investigated by correlation analysis. [ Result] Sweet potato leaves contain the bioactive substances scavenging DPPH free radical and hydroxyl free radical. Extracting solvent species is the most important factor that influencing extraction yield. The optimal extraction and storage conditions are as following: water as solvent, pH 8.0 of extracting liquid, storage at 25 ℃. There is a good positive linear relationship between the content of total phenols in sweet potato leaves and corresponding scavenging rates against both the DPPH free radical and hydroxyl free radical. For the content of total flavones in sweet potato leaves, just a correlation with scavenging rate against hydroxyl free radical shown in test. [ Conclusion] The phenols in ex- tracts could effectively scavenge both the DPPH free radical and hydroxyl free radical, whereas the flavones in extracts can only function on the hydroxyl free radical. 展开更多
关键词 Sweet potato leaves Free radicals scavenging Total phenol Total flavones
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Rigorous back analysis of shear strength parameters of landslide slip 被引量:6
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作者 张科 曹平 保瑞 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第5期1459-1464,共6页
A rigorous back analysis of shear strength parameters of landslide slip was presented. Kinematical element method was adopted to determine factor of safety and critical failure surface, which overcomes the disadvantag... A rigorous back analysis of shear strength parameters of landslide slip was presented. Kinematical element method was adopted to determine factor of safety and critical failure surface, which overcomes the disadvantage of limit equilibrium method. The theoretical relationship between the combination of shear strength parameters and stability state was studied. The results show that the location of critical slip surface, F/tan f and F/c depend only on the value of c/tan f. The failure surface moves towards the inside of slope as c/tan f increases. According to the information involving factor of safety and critical failure surface in a specific cross-section, strength parameters can be back calculated based on the above findings. Three examples were given for demonstrating the validity of the present method. The shear strength parameters obtained by back analysis are almost consistent with their correct solutions or test results. 展开更多
关键词 slope stability back analysis kinematical element method shear strength parameter critical failure surface
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Wrinkling prediction in rubber forming of Ti-15-3 alloy 被引量:4
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作者 孙永娜 万敏 吴向东 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第10期3002-3010,共9页
Wrinkling is a common failure in the sheet metal forming of titanium owing to the relatively poor ability to shrink. It is important to predict wrinkling accurately in the sheet metal forming without costly trials. Th... Wrinkling is a common failure in the sheet metal forming of titanium owing to the relatively poor ability to shrink. It is important to predict wrinkling accurately in the sheet metal forming without costly trials. The ABAQUS/Explicit code was utilized to predict the wrinkling behavior in the sheet metal forming of Ti-15-3 alloy sheets. In terms of the comparison of wrinkling behavior between the simulation and experiment of the Fukui's conical cup tests at room temperature, the sensitivities of wrinkling simulation to various input parameters were evaluated comprehensively and quantitatively. Prediction of wrinkling and influence of rubber hardness on the winkling behavior in the rubber forming of convex flange were investigated quantitatively and validated by the rubber forming experiments. The excellent agreements between the simulations and the experiments conIirmed the accuracy of the prediction. 展开更多
关键词 Ti-15-3 alloy WRINKLING convex flange rubber forming quantitative analysis
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Improvement of Resistance to Rice Blast in Zhenshan 97 by Molecular Marker-aided Selection 被引量:46
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作者 刘士平 李信 +2 位作者 汪朝阳 李香花 何予卿 《Acta Botanica Sinica》 CSCD 2003年第11期1346-1350,共5页
Fungi blast is one of the most serious diseases of rice worldwide. Breeding resistant varieties have been proved to be the most effective and economical means to control the disease. This paper describes the molecular... Fungi blast is one of the most serious diseases of rice worldwide. Breeding resistant varieties have been proved to be the most effective and economical means to control the disease. This paper describes the molecular marker-assisted selection (MAS) procedure for a broad-spectrum blast resistant gene Pi1 integrated into an elite hybrid maintainer line, Zhenshan 97. A simple sequence repeat (SSR) based on molecular marker-aided selection system for Pi1 segment was established. Using a backcross population and a blast isolate F1829, Pi1 gene was mapped on the top of chromosome 11 between markers RZ536 and RM144, with a distance of 9.7 cM and 6.8 cM, respectively. Seventeen families derived from the recurrent parent Zhenshan 97 were obtained with homozygous Pi1 gene. The background of the 17 families was identified with inter simple sequence repeat (ISSR) amplification, the highest recovery of the Zhenshan 97 genetic background was 97.01% after the assay of 167 polymorphic bands. 展开更多
关键词 fungi blast gene tagging Pi1 molecular marker-assisted selection Oryza sativa
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Analysis of stability and bullwhip effect in production-inventory systems 被引量:5
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作者 张冲 王海燕 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期101-106,共6页
To discuss the relationship between stability and bullwhip effect in the supply chain system,a basic model in a production-inventory control system is developed using difference equations.Z-transform techniques are ap... To discuss the relationship between stability and bullwhip effect in the supply chain system,a basic model in a production-inventory control system is developed using difference equations.Z-transform techniques are applied to investigate the production ordering and inventory dynamics.For the two operational regimes of sufficient inventory coverage and insufficient inventory coverage,the scope of decision parameters which make the system stable or instable is investigated.Under two operational regimes and the actual system,production release rates,stability/instability and bullwhip effect in the stable region and instable region are examined based on different demand functions,and then the numerical simulation results are given.The results show that reasonable choices of fractional adjustment of inventory and supply line can make the system stable and decrease bullwhip effect.It is summarized that the piecewise linearization based on the stability analysis approach is a valid approximation to the analysis of production-inventory ordering systems with nonlinearities.Some interesting results are obtained and they have important implications for improving inventory and order decisions in supply chain systems. 展开更多
关键词 production-inventory systems stability analysis bullwhip effect Z-TRANSFORM
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Determination of Melamine by Infrared Spectroscopy Based on Nonlinear Modeling 被引量:1
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作者 张恒 高曼侠 +2 位作者 许兆棠 李文谦 王琪 《Agricultural Science & Technology》 CAS 2010年第8期133-136,共4页
[Objective] The aim was to develop a nonlinear model of quantitative analysis of melamine content by infrared spectroscopy and provide theoretical basis for the nondestructive detection of melamine. [Method] According... [Objective] The aim was to develop a nonlinear model of quantitative analysis of melamine content by infrared spectroscopy and provide theoretical basis for the nondestructive detection of melamine. [Method] According to dynamics,mathematical modeling and optimization theory,linear and nonlinear models were respectively set up by taking an absorption peak of 1 550 cm-1 as characteristic absorption peak. [Result] The correlation coefficient of nonlinear model was 0.922 7 and the recovery was 96%,which showed that the nonlinear model was more accurate than linearity model with correlation coefficient of 0.904 9 and recovery of 557%. [Conclusion] It is feasible to determine melamine content by using the nonlinear model quantitatively. 展开更多
关键词 Infrared spectroscopy Quantitative analysis Nonlinear model MELAMINE
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Qualitative and Quantitative Analysis of Rhizoma of Polygonum cuspidatum 被引量:4
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作者 张勉 王磊 +2 位作者 黄澜 张紫佳 王峥涛 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第2期106-111,共6页
Aim To establish reliable methods for evaluating the quality of rhizoma of Polygonum cuspidatum( Huzhang in Chinese). Methods TLC and HPLC were employed for the chemical identification and content determination,respec... Aim To establish reliable methods for evaluating the quality of rhizoma of Polygonum cuspidatum( Huzhang in Chinese). Methods TLC and HPLC were employed for the chemical identification and content determination,respectively. Results A qualitative TLC method and a quantitative HPLC method with piceid as the reference substance were established, respectively. With piceid as the reference substance and ethyl acetate-methanol-formic acid-water ( 19:3:0.5:1) as the mobile phase, a TLC method for the identification of Huzhang from the commonly used crude drugs of the same family was also set up. Conclusion The established TLC method can reasonably appraise the quality of the drug and easily distinguish Huzhang from the other commonly used crude drugs of the same family. The HPLC method for determining piceid is simple, reproducible, accurate, and feasible. 展开更多
关键词 TLC HPLC PICEID EMODIN rhizoma of Polygonum cuspidatum
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Identification of Drought Tolerance in Peanut (Arachis hypogaea) Germplasm at Seedling Stage 被引量:2
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作者 刘永惠 沈一 陈志德 《Agricultural Science & Technology》 CAS 2015年第9期1873-1876,共4页
[Objective] This study was conducted to identify the drought tolerance of peanut(Arachis hypogaea) seedlings. [Method] The plant height, fresh weight and dry weight of 80 peanut varieties or lines were determined un... [Objective] This study was conducted to identify the drought tolerance of peanut(Arachis hypogaea) seedlings. [Method] The plant height, fresh weight and dry weight of 80 peanut varieties or lines were determined under the drought stress simulated using 15% PEG6000 in laboratory. Relative values of the three indices were calculated to measure the drought tolerance of the 80 peanut varieties or lines. [Result] The growth of peanut seedlings was significantly inhibited after 10 d of drought treatment. Cluster analysis revealed that at Euclidean distance D=15, the80 peanut varieties or lines were divided into four categories A, B, C and D. Among them, category B had better drought tolerance while category C was sensitive to drought. In all the four categories, the approved peanut varieties or lines showed better drought tolerance than the unapproved ones. [Conclusion] The drought tolerant and the drought sensitive peanut varieties or lines screened in this study can be used for further basic research and germplasm improvement. 展开更多
关键词 PEANUT SEEDLING Drought tolerance Cluster analysis
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