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Characteristics of Retoon Rice Yield Components and Relationship of the Characteristics with Rate of Bud Emergence and Root Activity 被引量:3
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作者 张林 熊洪 +3 位作者 徐富贤 郭晓艺 朱永川 刘茂 《Agricultural Science & Technology》 CAS 2013年第12期1733-1736,共4页
[Objective] The aim was to study on characteristics of retoon rice yield components, and relationship of the characteristics with born bud rate and root ac- tivity of retoon rice before harvesting. [Method] Eighteen m... [Objective] The aim was to study on characteristics of retoon rice yield components, and relationship of the characteristics with born bud rate and root ac- tivity of retoon rice before harvesting. [Method] Eighteen mid-season hybrid rice va- rieties approved recently were taken as materials in high-yield cultivation conditions. Characteristics of retoon rice yield components were analyzed, and relationship of yield components characteristics with the rate of bud emergence and root activity of retoon rice before harvesting was explored, based on related data. [Result] Highly- yielding retoon rice is characterized by high effective ear number (Xl) and high set- ting percentage (X4); the number of germinated shoots the 5^* d after first-batch rice was cut is a key factor for retoon rice yield and was of positive correlation with re- toon rice seedlings and effective ears, with correlation coefficients at 0.80^** and 0.76^**. In addition, bleeding sap was of positive correlation with grain number and setting percentage of retoon rice and correlation coefficients were 0.50^* and 0.48^**, and of positive correlation with average panicle weight, with correlation coefficient at 0.63. [Conclusion] It is an effective way for the rate of bud emergence and root activity at lar ecological zones. mproving retoon rice yield to increase harvesting in the test sites and simi lar ecological zones. 展开更多
关键词 Retoon rice characteristics of yield components Rate of bud emer-gence Root activity
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Impact of Winter Transit Air Masses on the Sources and Composition Characteristics of Atmospheric Pollution in Hengyang
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作者 Wenhui YAO Huili JIANG +1 位作者 Chunling XU Wei ZHOU 《Meteorological and Environmental Research》 CAS 2023年第3期30-36,共7页
Through the integration and analysis platform of particulate matter components,a preliminary comparison was conducted on the pollution contribution of the three winter transit air masses in December to environmental q... Through the integration and analysis platform of particulate matter components,a preliminary comparison was conducted on the pollution contribution of the three winter transit air masses in December to environmental quality,and the changes and related relationships of water-soluble ions and particulate matter elements were analyzed.The results showed that winter transit air masses had a significant impact on the air quality in Hengyang.In the quantitative comparison of the primary pollutant contribution during the transit period of air masses,local sources and transit sources each accounted for half,and the impact of transit source on ambient air quality was much greater than that of seasonal base increase.Fine particulate matter was closely related to secondary ions,and particulate matter was closely related to primary ions.The transit of air masses promoted the improvement of secondary ion conversion rate,and the unit increment of fine particulate matter was greater than that of particulate matter.During the transit period,the mass concentrations of most water-soluble ions and most particulate matter elements maintained synchronous growth,with a superimposed effect.The composition ratio of organic carbon and nitrate ions increased,while the composition ratio of ammonia and sulfate ions decreased.Both disposable ions and secondary conversions in the composition of PM_(2.5)had increases and decreases.The high conversion rate of nitrate and the high composition ratio of ammonia radical in Hengyang indicated that transportation source factors had a significant impact on the local environmental quality of Hengyang. 展开更多
关键词 Transit transmission component characteristics Fine particulate matter Water-soluble ion Particulate matter element
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Evaluating gravity gradient components based on a reweighted inversion method
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作者 Cao Ju-Liang Qin Peng-Bo Hou Zhen-Long 《Applied Geophysics》 SCIE CSCD 2019年第4期491-506,561,共17页
In gravity gradient inversion,to choose an appropriate component combination is very important,that needs to understand the function of each component of gravity gradient in the inversion.In this paper,based on the pr... In gravity gradient inversion,to choose an appropriate component combination is very important,that needs to understand the function of each component of gravity gradient in the inversion.In this paper,based on the previous research on the characteristics of gravity gradient components,we propose a reweighted inversion method to evaluate the influence of single gravity gradient component on the inversion resolution The proposed method only adopts the misfit function of the regularized equation and introduce a depth weighting function to overcome skin effect produced in gravity gradient inversion.A comparison between different inversion results was undertaken to verify the influence of the depth weighting function on the inversion result resolution.To avoid the premise of introducing prior information,we select the depth weighting function based on the sensitivity matrix.The inversion results using the single-prism model and the complex model show that the influence of different components on the resolution of inversion results is different in different directions,however,the inversion results based on two kind of models with adding different levels of random noise are basically consistent with the results of inversion without noises.Finally,the method was applied to real data from the Vinton salt dome,Louisiana,USA. 展开更多
关键词 Reweighted inversion method depth weighting function gravity gradient component characteristics
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Determining the in vitro Anti-Aging Effect of the Characteristic Components from Eucommia ulmoides 被引量:1
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作者 Xuesong Wang Zhihong Wang +2 位作者 Qiuling Yang Sheng Peng Mijun Peng 《Journal of Renewable Materials》 SCIE EI 2022年第12期3131-3145,共15页
To evaluate the potential anti-aging ability of Eucommia ulmoides,four characteristic components(chlorogenic acid,geniposidic acid,aucubin,quercetin)were selected to assess their effects on H_(2)O_(2)-induced oxidativ... To evaluate the potential anti-aging ability of Eucommia ulmoides,four characteristic components(chlorogenic acid,geniposidic acid,aucubin,quercetin)were selected to assess their effects on H_(2)O_(2)-induced oxidative damage model of human umbilical vein endothelial cell(HUVEC).Oxidative damage indexes,inflammatory factors,cell cycle,cell apoptosis,cell senescence,and their related proteins were analyzed by methyl thiazolyl tetrazolium(MTT)assay,enzyme-linked immunosorbent assay(ELISA),propidium iodide(PI)staining,annexin V-FITC/PI double staining,SAβ-galactosidase staining,and western blotting(WB).The results showed that H_(2)O_(2)-induced cell growth inhibition rate decreased as supplementation with characteristic components when compared to H_(2)O_(2) group.Meanwhile,the contents of antioxidant indexes(reactive oxygen species,lactate dehydrogenase,molondialdehyde,superoxide dismutase,glutathione),inflammatory factors(nuclear factor kappa-B,intercellular cell adhesion molecule-1,vascular cell adhesion protein 1),and functional factors(NO,Endothelin-1)in characteristic components treated groups improved if comparison with H_(2)O_(2) group,suggesting the characteristic components of E.ulmoides could alleviate H_(2)O_(2)-induced oxidative damage.Moreover,cell cycle,cell apoptosis,cell senescence,and their related proteins under characteristic components treatment exhibited a better effect than under H_(2)O_(2) treatment,implying the characteristic components could participate in anti-aging via multiple pathways.These results manifested that the characteristic components of E.ulmoides posses the capacity of anti-aging,which provided a basis for investigating the anti-aging ability of E.ulmoides itself. 展开更多
关键词 ANTI-AGING Eucommia ulmoides characteristic components oxidative damage cell senescence
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Some Characteristic Parameters of the Basic Components of the Solar Radio Emission 被引量:1
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作者 Ji Shuchen (Beijing Astronomical Observatory, The Chinese Academy of Sciences, Beijing 100080, China) (Yunnan Observatory, The Chinese Academy of Sciences, Kunming 650011, China) (National Astronomical Observatories, The Chinese Academy of Sciences) $$ 《天文研究与技术》 CSCD 1999年第S1期457-460,共4页
Four basic components of the solar radio emission: the quiet sun, the slowly varying component (SVC), the radio burst and the ultra-fast varying component (UFVC) are studied. As their six characteristic parameters: ra... Four basic components of the solar radio emission: the quiet sun, the slowly varying component (SVC), the radio burst and the ultra-fast varying component (UFVC) are studied. As their six characteristic parameters: radiation source, brightness temperature, radiation lifetime, polarized radiation, radiation mechanism, and character of superposition are affirmed. 展开更多
关键词 RADIO Some Characteristic Parameters of the Basic components Basic of the Solar Radio Emission
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Hyper-spectral characteristics and classification of farmland soil in northeast of China
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作者 LU Yan-li BAI You-lu +4 位作者 YANG Li-ping WANG Lei WANG Yi-lun NI Lu ZHOU Li-ping 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第12期2521-2528,共8页
The physical and chemical heterogeneities of soils make the soil spectral different and complicated, and it is valuable to increase the accuracy of prediction models for soil organic matter(SOM) based on pre-classif... The physical and chemical heterogeneities of soils make the soil spectral different and complicated, and it is valuable to increase the accuracy of prediction models for soil organic matter(SOM) based on pre-classification. This experiment was conducted under a controllable environment, and different soil samples from northeast of China were measured using ASD2500 hyperspectral instrument. The results showed that there are different reflectances in different soil types. There are statistically significant correlation between SOM and reflectence at 0.05 and 0.01 levels in 550–850 nm, and all soil types get significant at 0.01 level in 650–750 nm. The results indicated that soil types of the northeast can be divided into three categories: The first category shows relatively flat and low reflectance in the entire band; the second shows that the spectral reflectance curve raises fastest in 460–610 nm band, the sharp increase in the slope, but uneven slope changes; the third category slowly uplifts in the visible band, and its slope in the visible band is obviously higher than the first category. Except for the classification by curve shapes of reflectance, principal component analysis is one more effective method to classify soil types. The first principal component includes 62.13–97.19% of spectral information and it mainly relates to the information in 560–600, 630–690 and 690–760 nm. The second mainly represents spectral information in 1 640–1 740, 2 050–2 120 and 2 200–2 300 nm. The samples with high OM are often in the left, and the others with low OM are in the right of the scatter plot(the first principal component is the horizontal axis and the second is the longitudinal axis). Soil types in northeast of China can be classified effectively by those two principles; it is also a valuable reference to other soil in other areas. 展开更多
关键词 soil type spectral characteristics principle component classification
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