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Selection of Tree and Shrub Species for Ecological Recovery in Jari Demonstration Plot in Ethiopia
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作者 汪洋 《Journal of Landscape Research》 2010年第7期11-14,共4页
Environmental degradation and deforestation in Jari Demonstration Plot needed forestation and reforestation,and the plant species selection was a key issue in the ecological recovery.Ecological information was fully c... Environmental degradation and deforestation in Jari Demonstration Plot needed forestation and reforestation,and the plant species selection was a key issue in the ecological recovery.Ecological information was fully considered regarding each species in various agro-climatic zones,altitude ranges,specific niches in different landscapes,soil preference,drought resistance and certain other important ecological factors.The species selection model represents an idea of ecological recovery and soil erosion control in the demonstration plot. 展开更多
关键词 Jari DEMONSTRATION plot SPECIES selection Indigenous SPECIES EXOTIC SPECIES ECOLOGICAL recovery
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Grain selection and growth orientation of prior-β phase for Ti-6-4 during additive manufacturing:insights from a modeling perspective
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作者 Wei-zhao Sun Fei-hu Shan +2 位作者 Nan-fu Zong Hong-biao Dong Tao Jing 《China Foundry》 SCIE CAS 2021年第2期83-93,共11页
The microstructure of Ti-6-4 components produced by additive manufacturing suffers from the coarse and elongated prior-β grain,which leads to a decrease of the tensile behavior and the occurrence of anisotropy.To und... The microstructure of Ti-6-4 components produced by additive manufacturing suffers from the coarse and elongated prior-β grain,which leads to a decrease of the tensile behavior and the occurrence of anisotropy.To understand and control the grain evolution,a multiscale simulation is applied to investigate the relationship between the grain selection,growth orientation,and the molten pool morphology with the different deposition layer numbers and processing parameters.The accuracy of the simulation is validated by experiments in both qualitative and quantitative ways.Results show that when the grain with unfavorable orientation loses the competitive growth with its neighbors,there will be a great chance that the blocked grain is eliminated in the following layer-and-layer deposition,which leads to the increase of the grain width.The size of the molten pool increases remarkably as the layer number increases,which lays a heavy burden on the stability of the molten pool.The analytical relationship between the molten pool morphology and the grain growth orientation is also deduced.The flat molten pool causes the grains with the <001> direction close to the building direction to have greater survival potential.Besides,decreasing the line power energy shows little effect on the stability of the molten pool and the grain growth orientation,especially when the deposited layer number is large.The revealing mechanisms will help in understanding and further controlling the grain evolution. 展开更多
关键词 additive manufacturing Ti-6-4 simulation grain selection grain growth
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Molecular mapping of a novel wheat powdery mildew resistance gene Ml92145E8-9 and its application in wheat breeding by marker-assisted selection
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作者 Xiaocheng Yu Shizhong Ren +8 位作者 Lanfei Zhao Jun Guo Yinguang Bao Yingxue Ma Hongwei Wang Herbert W.Ohm Dazhao Yu Hongjie Li Lingrang Kong 《The Crop Journal》 SCIE CAS CSCD 2018年第6期621-627,共7页
Powdery mildew, caused by Blumeria graminis f. sp. tritici(Bgt), is one of the most devastating diseases of common wheat(Triticum aestivum L.). The wheat line 92145 E8-9 is immune to Bgt isolate E09. Genetic analysis ... Powdery mildew, caused by Blumeria graminis f. sp. tritici(Bgt), is one of the most devastating diseases of common wheat(Triticum aestivum L.). The wheat line 92145 E8-9 is immune to Bgt isolate E09. Genetic analysis reveals that the powdery mildew resistance in 92145 E8-9 is controlled by a single dominant gene, temporarily designated Ml92145 E8-9. Bulkedsegregant analysis(BSA) with simple sequence repeat(SSR) markers indicates that Ml92145 E8-9 is located on chromosome 2 AL. According to the reactions of 92145 E8-9,VPM1(Pm4 b carrier), and Lankao 906(PmLK906 carrier) to 14 Bgt isolates, the resistance spectrum of 92145 E8-9 differs from those of Pm4 b and PmLK906, both of which were previously localized to 2 AL. To test the allelism among Ml92145 E8-9, Pm4 b and PmLK906, two F2 populations of 92145 E8-9 × VPM1(Pm4 b) and 92145 E8-9 × Lankao 906(PmLK906) were developed in this study. Screening of 784 F2 progeny of 92145 E8-9 × VPM1 and 973 F2 progeny of 92145 E8-9 × Lankao 906 for Bgt isolate E09 identified 37 and 19 susceptible plants, respectively. These findings indicated that Ml92145 E8-9 is non-allelic to either Pm4 b or PmLK906. Thus, Ml92145 E8-9 is likely to be a new powdery mildew resistance gene on2 AL. New polymorphic markers were developed based on the collinearity of genomic regions of Ml92145 E8-9 with the reference sequences of the International Wheat Genome Sequencing Consortium(IWGSC). Ml92145 E8-9 was mapped to a 3.6 c M interval flanked by molecular markers Xsdauk13 and Xsdauk682. This study also developed five powdery mildew-resistant wheat lines(SDAU3561, SDAU3562, SDAU4173, SDAU4174, and SDAU4175)using flanking marker-aided selection. The markers closely linked to Ml92145 E8-9 would be useful in marker-assisted selection for wheat powdery mildew resistance breeding. 展开更多
关键词 Marker-assisted selection Ml92145E8-9 Powdery MILDEW TRITICUM AESTIVUM L.
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PLOT柱分离GC-MS法测定酿酒发酵产品中的微量丁二酮和苯乙烯 被引量:3
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作者 刘绍从 吕刚 +2 位作者 赵好力宝 李德泉 刘军 《分析测试学报》 CAS CSCD 北大核心 2006年第1期127-129,共3页
用PLOT柱分离,气相色谱-质谱联用对酿酒发酵产品中微量丁二酮和苯乙烯含量进行测定。GC条件为:毛细管色谱柱,HP-PLOTU,30m×0.32mm×10μm;载气(He)流速,1.5mL/min;进样口温度,200℃;柱温,180℃;分流比。50:1... 用PLOT柱分离,气相色谱-质谱联用对酿酒发酵产品中微量丁二酮和苯乙烯含量进行测定。GC条件为:毛细管色谱柱,HP-PLOTU,30m×0.32mm×10μm;载气(He)流速,1.5mL/min;进样口温度,200℃;柱温,180℃;分流比。50:1;进样量0.5μL。MS条件:电子轰击电离源能量。70eV;选择离子扫描方式;溶剂延迟。3.0min。结果表明:丁二酬和乙醇达到基线分离。在25min内一次完成对酿酒发酵产品中微量丁二酮和苯乙烯含量的分离测定。方法的检出限为0.01mg/L,相对标准偏差小于2.0%,平均加标回收率为95%~104%。 展开更多
关键词 plot 气相色谱-质谱 丁二酮 苯乙烯 酿酒发酵产品
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Two Probability Plots of the Three-Parameter Lognormal Distribution
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作者 蒋仁言 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期757-759,共3页
The two-parameter lognormal distribution is a variant of the normal distribution and the three-parameter lognormal distribution is an extension of the two-parameter lognormal distribution by introducing a location par... The two-parameter lognormal distribution is a variant of the normal distribution and the three-parameter lognormal distribution is an extension of the two-parameter lognormal distribution by introducing a location parameter. The Q-Q plot of the three-parameter lognormal distribution is widely used. To obtain the Q-Q plot one needs to iteratively try different values of the shape parameter and subjectively judge the linearity of the Q-Q plot. In this paper,a mathematical method was proposed to determine the value of the shape parameter so as to simplify the generation of the Q-Q plot. Then a new probability plot was proposed,which was more easily obtained and provided more accurate parameter estimates than the Q-Q plot. These are illustrated by three realworld examples. 展开更多
关键词 three-parameter lognormal distribution probability plot correlation coefficient model selection parameter estimation
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Test of Normality of Waist Measurement Data of Young Male and Female Adults based on the Quantile - Quantile Plot
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作者 F. Z. Okwonu J. N. Igabari 《Journal of Statistical Science and Application》 2017年第3期118-126,共9页
This paper investigates the normality of some real data set obtained from waist measurements of a group of 49 young adults. The quantile - quantile (Q-Q) plot and the analysis of correlation coefficients for the Q-Q... This paper investigates the normality of some real data set obtained from waist measurements of a group of 49 young adults. The quantile - quantile (Q-Q) plot and the analysis of correlation coefficients for the Q-Q plot is used to determine the normality or otherwise of the data set. In this regards, the probabilities of the quantiles were computed, modified and plotted. Thereafter the correlation coefficients for the quantile - quantile plots were obtained. Results indicate that at 0.1 level of significance, the data for young adult males of the sample were not normally distributed, and had a mean value that is within the range of low risk, healthwise, whereas the distribution of the data for young female adults showed reasonable normality, but also with a mean value that is within the range of low risk in terms of health condition. 展开更多
关键词 Correlation coefficient probability plot quantile - quantile plot test of normality waist measurement young adults.
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Bayesian Variable Selection for Mixture Process Variable Design Experiment 被引量:1
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作者 Sadiah M. A. Aljeddani 《Open Journal of Modelling and Simulation》 2022年第4期391-416,共26页
This paper discussed Bayesian variable selection methods for models from split-plot mixture designs using samples from Metropolis-Hastings within the Gibbs sampling algorithm. Bayesian variable selection is easy to im... This paper discussed Bayesian variable selection methods for models from split-plot mixture designs using samples from Metropolis-Hastings within the Gibbs sampling algorithm. Bayesian variable selection is easy to implement due to the improvement in computing via MCMC sampling. We described the Bayesian methodology by introducing the Bayesian framework, and explaining Markov Chain Monte Carlo (MCMC) sampling. The Metropolis-Hastings within Gibbs sampling was used to draw dependent samples from the full conditional distributions which were explained. In mixture experiments with process variables, the response depends not only on the proportions of the mixture components but also on the effects of the process variables. In many such mixture-process variable experiments, constraints such as time or cost prohibit the selection of treatments completely at random. In these situations, restrictions on the randomisation force the level combinations of one group of factors to be fixed and the combinations of the other group of factors are run. Then a new level of the first-factor group is set and combinations of the other factors are run. We discussed the computational algorithm for the Stochastic Search Variable Selection (SSVS) in linear mixed models. We extended the computational algorithm of SSVS to fit models from split-plot mixture design by introducing the algorithm of the Stochastic Search Variable Selection for Split-plot Design (SSVS-SPD). The motivation of this extension is that we have two different levels of the experimental units, one for the whole plots and the other for subplots in the split-plot mixture design. 展开更多
关键词 Variable selection Bayesian Analysis Mixture Experiment Split-plot Design
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Information Environmental sciences update referneces in Chinese journals——Selected from Acta Scientiae Circumstantiae,ISSN 0253-2468;Environental Chemistry,ISSN0254-6108;Acta Ecologica Sinica,ISSN 100-0933
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《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1993年第2期241-243,共3页
关键词 ISSN Information Environmental sciences update referneces in Chinese journals selected from Acta Scientiae Circumstantiae ISSN 0253-2468 Environental Chemistry ISSN0254-6108 Acta Ecologica Sinica ISSN 100-0933
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评估小麦—黑麦重组系“Selection 212”对叶锈和秆锈的抗性
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作者 J.B.Sharma 邱郭莲 《国外作物育种》 2002年第1期23-23,共1页
关键词 小麦-黑麦 重组系 selection212 叶锈 秆锈 抗性
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Table 1.FDI flows,by region and selected countries,1994-2005
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《China Textile》 2006年第4期7-7,共1页
关键词 FDI Table 1.FDI flows by region and selected countries 1994-2005
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气相色谱-质谱法测定食用酒精中的微量丁二酮和苯乙烯 被引量:3
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作者 刘绍从 吕刚 +2 位作者 张莱 赵好力宝 孙书军 《色谱》 CAS CSCD 北大核心 2006年第2期210-210,共1页
关键词 plot柱(plot column) 气相色谱-质谱(gas chromatography-mass spectrometry) 丁二酮(2 3-butanedione) 苯乙烯(styrene) 食用酒精(drinkable alcohol)
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Breeding and Cultivation Techniques of Edible Sunflower Variety AR9-9293 被引量:3
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作者 刘胜利 柳延涛 +3 位作者 王鹏 李万云 王波 段维 《Agricultural Science & Technology》 CAS 2017年第9期1642-1644,共3页
Edible sunflower variety AR9-9293 was approved by the Sunflower Variety Appraisal Committee with the country Identification number of sunflower 2015005. This paper introduced the breeding process, yield performance an... Edible sunflower variety AR9-9293 was approved by the Sunflower Variety Appraisal Committee with the country Identification number of sunflower 2015005. This paper introduced the breeding process, yield performance and characteristics, and the high-yield cultivation technology of new edible sunflower variety AR9-9293. The promotion of edible sunflower varieties and cultivation technology could achieve the effects of improving the level of the sunflower cultivation, promoting the development of rural and agricultural economy and increasing farmers' income, as well as positively promoting development of the society and adjusting agricultural industry structure. 展开更多
关键词 New oil sunflower hybrid AR9-9293 selection Cultivation technology
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应用不完全双列杂交及裂区-间比设计选育杂交水稻强优势组合
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作者 周乐良 伍祥 汤鸿钧 《贵州农业科学》 CAS 2002年第3期3-7,共5页
用 4个自选的新恢复系与 7个不育系 ,按不完全双列方式配组出 2 8个杂交组合 ,应用裂区 -间比设计进行品比试验分析 ,估算亲本 6个重要性状的一般配合力和特殊配合力。结果表明 :新选育的中九A/ Q0 2 6 85、K17A/ Q0 2 6 85、新香 A/ Q8... 用 4个自选的新恢复系与 7个不育系 ,按不完全双列方式配组出 2 8个杂交组合 ,应用裂区 -间比设计进行品比试验分析 ,估算亲本 6个重要性状的一般配合力和特殊配合力。结果表明 :新选育的中九A/ Q0 2 6 85、K17A/ Q0 2 6 85、新香 A/ Q80 730等组合优势很强 ;新选育的恢复系 Q0 2 6 85、Q80 730一般配合力强。在优质育种上 ,以“同恢渗粳”方法选育的恢复系应选长粒、粒形长宽比大的不育系组配。 展开更多
关键词 杂交水稻 不完全双列杂交 裂区-间比设计 杂交组合 选育
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数据增强和复杂特征优化的类不平衡病理嗓音检测
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作者 武雅琴 张佳庆 张涛 《应用声学》 北大核心 2025年第1期234-244,共11页
该文以提高病理嗓音多分类准确性为目标,构建了一种基于数据增强和复杂特征优化的类不平衡病理嗓音检测系统。首先,对32种声学特征进行分析并将其归类为时域类特征和频域类特征;其次,采用改进的合成少数类过采样技术对数据集进行增广与... 该文以提高病理嗓音多分类准确性为目标,构建了一种基于数据增强和复杂特征优化的类不平衡病理嗓音检测系统。首先,对32种声学特征进行分析并将其归类为时域类特征和频域类特征;其次,采用改进的合成少数类过采样技术对数据集进行增广与均衡处理;然后,结合高效相关性特征选择算法和盒图对多维声学特征进行融合优化,综合评估各特征的判别能力;最后,基于随机森林分类器,详细分析和验证不同特征组合的分类性能。结果表明,该文提出的融合优化特征集(To、Fatr、Jita、sAPQ、vAm、NHR)在随机森林分类器下,对声带小结、息肉、水肿及麻痹4种病理嗓音的分类性能表现优异,取得了88.6%的分类准确率、88.4%的召回率、88.4%的F1分数和99.7%的AUC值。 展开更多
关键词 病理嗓音 数据增强 复杂特征 高效相关性特征选择 盒图
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气相色谱-负化学源质谱联用法测定水产品及食用油中氟乐灵的残留量 被引量:9
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作者 王莉 夏广辉 +5 位作者 沈伟健 吴斌 张睿 陆慧媛 沈崇钰 赵增运 《色谱》 CAS CSCD 北大核心 2014年第3期314-317,共4页
建立了一种可用于水产品及食用油中氟乐灵残留量分析的分散型固相萃取-气相色谱-负化学离子源质谱方法。水产品及食用油经乙腈提取,4℃冷藏后,采用分散型固相萃取法净化,由气相色谱-负化学离子源质谱选择离子监测技术进行测定与确证... 建立了一种可用于水产品及食用油中氟乐灵残留量分析的分散型固相萃取-气相色谱-负化学离子源质谱方法。水产品及食用油经乙腈提取,4℃冷藏后,采用分散型固相萃取法净化,由气相色谱-负化学离子源质谱选择离子监测技术进行测定与确证,同位素内标法定量。在1~40μg / L 范围内氟乐灵农药的线性关系良好;方法定量限(LOQ)为0.02μg / kg;对鳗鱼、烤鳗、梭子蟹、小龙虾、猪油和橄榄油等6种复杂基质进行1.0、2.0和3.0μg / kg 等3个水平的添加回收试验,平均回收率均处于80%~100%之间,RSD≤10.3%;无干扰现象出现。该方法可作为水产品及食用油中氟乐灵残留检测的确证方法。 展开更多
关键词 分散型固相萃取 气相色谱-负化学离子源质谱联用 选择离子监测 氟乐灵 水产品 食用油 disperse solid phase extraction( DSPE) gas chromatography-negative chemical ionization mass SPECTROMETRY ( GC-MS NCI ) selected ion monitoring ( SIM )
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Cleaner and convenient preparation of 3-(4,6-dimethoxy-pyrimidin-2-yloxy)-2-methyl-phenol 被引量:1
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作者 文岳中 方兆华 刘维屏 《Journal of Zhejiang University Science》 EI CSCD 2004年第8期956-959,共4页
Environmental concerns have highlighted the need of cleaner technologies. A cleaner, convenient and selective technology has been developed for the preparation of 3-(4,6-dimethoxy-pyrimidin-2-yloxy)-2-methyl-phenol (... Environmental concerns have highlighted the need of cleaner technologies. A cleaner, convenient and selective technology has been developed for the preparation of 3-(4,6-dimethoxy-pyrimidin-2-yloxy)-2-methyl-phenol (DPMP) from 2-methyl-benzene-1,3-diol in water as solvent. The isolated yield of DPMP is up to 86% in good selectivity. The product structure was characterized by conventional methods, H-NMR and MS. This technology belongs to the modern concept of 1 environmentally friendly low wastes or non-wastes technology (LWNWT). 展开更多
关键词 Cleaner preparation Greener technology selective synthesis 2-methyl-benzene-1 3-diol 3-(4 6-dimeth- oxy-pyrimidin-2-yloxy)-2-methyl-phenol
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Green fuel from coal via Fischer-Tropsch process: scenario of optimal condition of process and modelling
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作者 Hossein Atashil Somayyeh Veiskarami 《International Journal of Coal Science & Technology》 EI 2018年第2期230-243,共14页
Extracting, transportation and the using from fossil fuels can damage to the hydrosphere, the biosphere and the Earth's atmosphere. But humans always need to this valuable substance. The production of oil derivatives... Extracting, transportation and the using from fossil fuels can damage to the hydrosphere, the biosphere and the Earth's atmosphere. But humans always need to this valuable substance. The production of oil derivatives by means of forest waste and coal through the Fischer-Tropsch process is an appropriate solution for the cleanliness of all parts of the environment. For the production of favorite products by the synthesis of Fischer-Tropsch, the performance of the catalyst under different operating conditions should be predictable. For this reason, in this paper, eight mathematical models were determined for the selectivity of five products of methane, light hydrocarbons, gasoline, diesel and wax based on three factors of reduction temperature, time on stream, and He/CO ratio inlet gas on iron-based catalyst. The results showed that the reduction temperature factor had the most effective on the selectivity of hydrocarbon products, exception diesel, so that the increase of the reduction temperature led to increase of the selectivity of methane, light hydrocarbons, gasoline and reduce of the degree of selectivity of the wax and vice versa. For the diesel selectivity, factor of the He/CO ratio inlet gas was the most effective than other factors. 展开更多
关键词 Fischer-Tropsch process - selectivity model Iron based catalyst BIOMASS Oil derivatives
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Selective Oxidation of Methane to Methanol Using Molecular Oxygen on MoOx/(LaCoO3+Co3O4)Catalysts
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作者 Xin ZHANG, De Hua HE, Qi Jiang ZHANG, Bo Qing XU, Qi Ming ZHUState Key Laboratory of C1 Chemistry and Technology, Department of Chemistry, Tsinghua University, Beijing 100084 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第10期1066-1069,共4页
Comparatively high CH3OH selectivity (60.0%) and yield (6.7%) were obtained on MoOx/(LaCoO3+Co3O4) catalysts in selective oxidation of methane to methanol using molecular oxygen as oxidant. The interaction between MoO... Comparatively high CH3OH selectivity (60.0%) and yield (6.7%) were obtained on MoOx/(LaCoO3+Co3O4) catalysts in selective oxidation of methane to methanol using molecular oxygen as oxidant. The interaction between MoOx and La-Co-oxide modified the molecular structure of molybdenum oxide and the ratio of O7O ' on the catalyst surface, which controlled the catalytic performance of MoOx/(LaCoO3+Co3O4) catalysts. 展开更多
关键词 METHANE selective oxidation METHANOL molybdenum oxide species O-/O2- ratio.
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Study on Support Vector Machine Based on 1-Norm
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作者 潘美芹 贺国平 +2 位作者 韩丛英 薛欣 史有群 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期148-152,共5页
The model of optimization problem for Support Vector Machine(SVM) is provided, which based on the definitions of the dual norm and the distance between a point and its projection onto a given plane. The model of impro... The model of optimization problem for Support Vector Machine(SVM) is provided, which based on the definitions of the dual norm and the distance between a point and its projection onto a given plane. The model of improved Support Vector Machine based on 1-norm(1-SVM) is provided from the optimization problem, yet it is a discrete programming. With the smoothing technique and optimality knowledge, the discrete programming is changed into a continuous programming. Experimental results show that the algorithm is easy to implement and this method can select and suppress the problem features more efficiently. Illustrative examples show that the 1-SVM deal with the linear or nonlinear classification well. 展开更多
关键词 1- SVM best separating plane feature suppression feature selection.
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Synthesis of 3-O-Benzoyl-1 ,2-O-isopropylidene-a-D-allofuranose and Its Dimesylated Derivative
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作者 张卫红 孟祥启 +1 位作者 冯亚青 刘云华 《Transactions of Tianjin University》 EI CAS 2005年第6期440-445,共6页
Diisopropylidenated α-D-glucofuranose (1) was oxidated with CrO3-pyridine complex. Oxidated product and its hydrate were separated and were reduced together to synthesize diisopropylidenated α-D-allofuranose ( 3... Diisopropylidenated α-D-glucofuranose (1) was oxidated with CrO3-pyridine complex. Oxidated product and its hydrate were separated and were reduced together to synthesize diisopropylidenated α-D-allofuranose ( 3). The yield of 3 increased by 8% than that with only oxidated product as reduction substrate. Benzoylated derivative of 3 was selectively nydrolyzed and dimesylated to synthesize 3-O-benzoyl-1 .2- O- isopropylidene-α-D-allofuranose ( 5 ) and its dimesylated derivative respectively. The overall yield of 5 from 1 was 36%. Each step and final products were analyzed by ^1H-NMR spectra and other methods. The experiments showed that the influence of acetic acid concentration on selective hydrolysis was obvious. The hydrolysis yield was 81.8%. Oxidation. reduction and other procedures were practical and had application potential. 展开更多
关键词 3-O-benzoyl-1. 2-O-isopropylidene-α-D-allofuranose OXIDATION reduction - selective hydrolysis dimesylation
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