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Relationships between Cloud Droplet Spectral Relative Dispersion and Entrainment Rate and Their Impacting Factors
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作者 Shi LUO Chunsong LU +9 位作者 Yangang LIU Yaohui LI Wenhua GAO Yujun QIU Xiaoqi XU Junjun LI Lei ZHU Yuan WANG Junjie WU Xinlin YANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第12期2087-2106,I0016-I0019,共24页
Cloud microphysical properties are significantly affected by entrainment and mixing processes.However,it is unclear how the entrainment rate affects the relative dispersion of cloud droplet size distribution.Previousl... Cloud microphysical properties are significantly affected by entrainment and mixing processes.However,it is unclear how the entrainment rate affects the relative dispersion of cloud droplet size distribution.Previously,the relationship between relative dispersion and entrainment rate was found to be positive or negative.To reconcile the contrasting relationships,the Explicit Mixing Parcel Model is used to determine the underlying mechanisms.When evaporation is dominated by small droplets,and the entrained environmental air is further saturated during mixing,the relationship is negative.However,when the evaporation of big droplets is dominant,the relationship is positive.Whether or not the cloud condensation nuclei are considered in the entrained environmental air is a key factor as condensation on the entrained condensation nuclei is the main source of small droplets.However,if cloud condensation nuclei are not entrained,the relationship is positive.If cloud condensation nuclei are entrained,the relationship is dependent on many other factors.High values of vertical velocity,relative humidity of environmental air,and liquid water content,and low values of droplet number concentration,are more likely to cause the negative relationship since new saturation is easier to achieve by evaporation of small droplets.Further,the signs of the relationship are not strongly affected by the turbulence dissipation rate,but the higher dissipation rate causes the positive relationship to be more significant for a larger entrainment rate.A conceptual model is proposed to reconcile the contrasting relationships.This work enhances the understanding of relative dispersion and lays a foundation for the quantification of entrainment-mixing mechanisms. 展开更多
关键词 CLOUDS entrainment rate relative dispersion of cloud droplet size distribution mixing and evaporation
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Relationships of growth and mortality to enzymatic activity,and the relative mRNA expression of cultured scallops Patinopecten yessoensis in the Yellow Sea, China 被引量:2
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作者 LIU Chao WU Fucun +1 位作者 QUE Huayong ZHANG Guofan 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第4期1409-1422,共14页
The bottom aquaculture of yesso scallop (Patinopecten yessoensis) has developed rapidly in the north of Yellow Sea, China, but not without accompanying productivity problems. We, therefore, conducted field surveys to ... The bottom aquaculture of yesso scallop (Patinopecten yessoensis) has developed rapidly in the north of Yellow Sea, China, but not without accompanying productivity problems. We, therefore, conducted field surveys to investigate factors related to growth and mortality rates of bottom-cultured scallops after release. Specifically, we focused on the effects of total antioxidant capacity (TAOC) and three key enzymes involved in antioxidant and metabolic function:glutamic pyruvic transaminase (GPT), lactic dehydrogenase (LDH), and superoxide dismutase (SOD). Across summer and winter, we also measured the relative mRNA expression of GPT and SOD to understand their seasonal variation in the scallops, along with how such variation correlated to growth and mortality. Results show that bottom cultured scallops experienced mass mortality during the first six months post-release. During winter (December), scallops grew more rapidly and suffered less mortality than in summer (August). The observed lower performance probably resulted from less advantageous environmental factors during the summer seasons, such as high temperature and low dissolved oxygen. These environmental stressors enhance protein consumption while decreasing energetic resources in scallops. Furthermore, scallops in summer exhibited high antioxidant levels that probably competed for energy with process integral to growth and survival. These negative factors combined to elevate mortality rates. In conclusion, we provided evidence suggesting correlations between metabolic/antioxidant activity and growth and mortality of bottom-cultured yesso scallops. These correlations implied us an accurate method to estimate the performance of bottom culture system. Suggestions about innovative aquaculture techniques were also discussed in the study. Our results might provide a possible guideline to the improvement of bottom culture techniques for this commercially valuable seafood species. 展开更多
关键词 yesso SCALLOP (Patinopecten yessoensis) bottom culture GROWTH and MORTALITY rate antioxidant and metabolic activity relative mRNA expression
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Photosynthesis,Metabolite Composition and Anatomical Structure of Oryza sativa and Two Wild Relatives,O.grandiglumis and O.alta 被引量:2
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作者 Jwakyung SUNG Suyeon LEE +3 位作者 Jong-Wook CHUNG Gerald EDWARDS Hojin RYU Taewan KIM 《Rice science》 SCIE CSCD 2017年第4期218-227,共10页
Photosynthesis, enzyme activities and metabolite pools associated with primary carbon metabolism in leaves were studied in O. grandiglumis and O. alta (wild relatives of rice which produce high biomass) versus O. sa... Photosynthesis, enzyme activities and metabolite pools associated with primary carbon metabolism in leaves were studied in O. grandiglumis and O. alta (wild relatives of rice which produce high biomass) versus O. sativa (a japonica cultivar and a indica-japonica hybrid) to assess their potential for identifying traits which might be utilized to enhance rice productivity. The wild relatives had higher rates of photosynthesis on a fresh weight basis, and higher water use efficiency than the O. sativa lines. There were no striking differences in activities of a number of key enzymes in carbon and nitrogen metabolism between the wild relatives and cultivated rice lines. Along with higher rates of photosynthesis on a fresh weight basis, the leaves of the two wild species had higher nitrate content, higher levels of starch, glucose and fructose, and higher levels of organic acids (malate, succinate and acetate), compared to the O. sativa lines. The results suggested that O. grandiglumis and O. alta have differences in physiology and primary metabolism which might be exploited to improve growth and productivity of cultivated rice. 展开更多
关键词 CARBOHYDrate photosynthesis rate nitrogen assimilation metabolite composition leaf rice wild relative
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Relative energy zero ratio-based approach for identifying pulse-like ground motions 被引量:2
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作者 Liu Ping Li Ning +2 位作者 Ma Hua Xie Lili Zhou Baofeng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2020年第1期1-16,共16页
Pulse-like ground motions are capable of inflicting significant damage to structures. Efficient classification of pulse-like ground motion is of great importance when performing the seismic assessment in near-fault re... Pulse-like ground motions are capable of inflicting significant damage to structures. Efficient classification of pulse-like ground motion is of great importance when performing the seismic assessment in near-fault regions. In this study, a new method for identifying the velocity pulses is proposed, based on different trends of two parameters: the short-time energy and the short-time zero crossing rate of a ground motion record. A new pulse indicator, the relative energy zero ratio(REZR), is defined to qualitatively identify pulse-like features. The threshold for pulse-like ground motions is derived and compared with two other identification methods through statistical analysis. The proposed procedure not only shows good accuracy and efficiency when identifying pulse-like ground motions but also exhibits good performance for classifying records with high-frequency noise and discontinuous pulses. The REZR method does not require a waveform formula to express and fit the potential velocity pulses;it is a purely signal-based classification method. Finally, the proposed procedure is used to evaluate the contribution of pulse-like motions to the total input energy of a seismic record, which dramatically increases the seismic damage potential. 展开更多
关键词 pulse-like ground motion velocity pulse relative energy zero-crossing ratio short-time input energy shorttime zero crossing rate
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Spatial and Dynamic Analysis of Regional Sustainable Development Using Geographic Information System and Relative Carrying Capacity of Resources 被引量:3
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作者 Qi Wang Xiaodan Wang +3 位作者 Hua Tang Jun Li Haihu Ma Tianxing Cheng 《Natural Resources》 2011年第1期28-34,共7页
Relative carrying capacity of resources is an index to measure sustainable development through carrying capacity. Case studies of eleven cities in Zhejiang (Hangzhou, Ningbo, Wenzhou, Jiaxing, Huzhou, Shaoxing, Jinhua... Relative carrying capacity of resources is an index to measure sustainable development through carrying capacity. Case studies of eleven cities in Zhejiang (Hangzhou, Ningbo, Wenzhou, Jiaxing, Huzhou, Shaoxing, Jinhua, Quzhou, Zhoushan, Taizhou and Lishui) illustrated regional sustainable development approach. In this study, to provide insight into spatial and dynamic analysis of region sustainable development, we calculated the relative carrying capacity of land resources and economical resources and synthetical carrying capacity of resources in different cities in Zhejiang, and geographic information system was carried out. The results showed that all cities but Hangzhou and Ningbo were ecologically sustainable, and relative carrying capacity of land resources in northern and eastern Zhejiang was larger than those in southern and western Zhejiang. The sampling years of Wenzhou, Hangzhou and Ningbo contribution rates of land resource to synthetic carrying capacity were grouped into three stages, and there were two milestones trends and changes in 1996 and 2004, respectively. This study demonstrated that geographic information system and relative carrying capacity of resources are effective for assessment of region sustainable development, and provide policy guidelines for decision-making. 展开更多
关键词 GEOGRAPHIC Information System Arcgis relative Carrying Capacity of RESOURCES REGIONAL SUSTAINABLE Development CONTRIBUTION rate
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The Influence Law of Oil Relative Permeability on Water Cut 被引量:1
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作者 Yanhui Zhang Yingxian Liu +2 位作者 Hongyou Zhang Mengjun Bie Guangyi Sun 《Journal of Geoscience and Environment Protection》 2018年第9期223-232,共10页
Water cut is a key evaluation parameter for reservoir development evaluation. Relative permeability curve reflects reservoir characteristics and fluid characteristics. It is important to figure out the influence law o... Water cut is a key evaluation parameter for reservoir development evaluation. Relative permeability curve reflects reservoir characteristics and fluid characteristics. It is important to figure out the influence law of oil relative permeability on water cut. Based on the 269 relative permeability curves of Bohai oilfields, the distribution of oil index of Bohai oilfields were studied. On the basis, combined with Corey expression of relative permeability and fractional flow equation, the theoretical relationship between oil index and water cut increasing rate was established. Three end points of water cut increasing rate curve were proposed and the influence law between three end points and oil index was studied. The results show that the oil index has a linear relationship with three end points. When the value of water oil mobile ratio is large than 1, with the increase of oil index, maximum value of water cut increasing rate gradually increase. When the value of water oil mobile ratio is less than 10, oil index has great effect on recovery percent when water cut increasing rate reaches to the maximum value as well as water cut when water cut increasing rate reaches to the maximum value. The application of SS field shows that the theoretical value is consistent with the field data. 展开更多
关键词 Water CUT INCREASING rate OIL relative PERMEABILITY OIL index End Point of relative PERMEABILITY CURVE
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On the Relationship Between the Crustal Strain Rate and Seismicity:Detect the Source-Field Relation from the Crustal Strain Field 被引量:1
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作者 Zhang Guomin, Li Li, and Shi YaolinCenter for Analysis and Prediction, CSB, Beijing 100036, China Graduate School of Chinese Academy of Sciences, Beijing 100039, China 《Earthquake Research in China》 1999年第4期3-15,共13页
The relationship between the strain cumulative rate (i.e., the crustal strain rate, or CSR in short) and seismic activity is analyzed to develop a new method to determine risky regions for strong shocks within recent ... The relationship between the strain cumulative rate (i.e., the crustal strain rate, or CSR in short) and seismic activity is analyzed to develop a new method to determine risky regions for strong shocks within recent years by the recorded crustal strain field. Seismic activity, especially the recurrence period, is different in different areas. Ding Guoyu (1984) pointed out that, for different seismic regions, the difference in the recurrence period of strong earthquakes is mainly controlled by their difference in the rate of the tectonic movement, which is controlled by the seismogenic environment and the tectonic conditions. The method of determining the risky regions for strong shocks from the gradient of vertical strain rates observed in a geodetic survey is preliminarily tested with the earthquakes in recent years; the results show that this method is effective and useful for earthquake prediction. The relationship between CSR and seismicity in a specific region is studied with strain theories, 展开更多
关键词 CRUSTAL STRAIN STRAIN rate SEISMICITY source-field relatION
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Relative floatability as a criterion for evaluating the separation performance of phosphate from iron 被引量:1
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作者 Azizi Asghar Seyyed Alizade Ganji Seyyed Mohammad 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第3期451-458,共8页
This work was aimed to study the relative floatability of phosphate flotation by means of kinetic analysis.The relative floatability is important to determine how selectively the phosphate is separated from its impuri... This work was aimed to study the relative floatability of phosphate flotation by means of kinetic analysis.The relative floatability is important to determine how selectively the phosphate is separated from its impurities. The effects of pulp pH, solid content, reagents dosage(depressant, collector and co-collector) and conditioning time were investigated on the ratio of the modified rate constant of phosphate to the modified rate constant of iron(relative floatability). The results showed that a large dosage of depressant associated with a low value of collector resulted in a better relative floatability. Increasing the co-collector dosage, conditioning time and pH increased the relative floatability up to a certain value and thereafter resulted in diminishing the relative floatability. Meanwhile, the results indicated that increment of solid concentration increased the relative floatability in range investigated. It was also found that that maximum relative floatability(16.05) could be obtained in pulp pH, 9.32, solid percentage, 30,depressant dosage, 440 g/t, collector dosage, 560 g/t, co-collector dosage, 84.63 g/t and conditioning time,9.43 min. 展开更多
关键词 Phosphate relative floatability Kinetics rate constant Separation
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QTL analysis of leaf photosynthetic rate and related physiological traits in rice(Oryza sativa L.) 被引量:3
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作者 TENG Sheng, QIAN Qian, ZENG Dali, Yasufumi Kunihiro, Hiroshi Fujimoto, HUANG Daman, and ZHU Lihuang, Key Lab for Rice Biology, CNRRI, Hangzhou 310006 Inst of Genetics and Development Biology, the Chinese Academy of Sciences, Beijing 100101 +1 位作者 College of Life Sci, Zhejiang Univ, Hangzhou 310029, China Japan International Res Center for Agri Sci, Tsukuba, Japan 《Chinese Rice Research Newsletter》 2002年第3期4-6,共3页
Photosynthesis is one of the most important factors that influence the biomass and yield. Recently, more attention has been paid to genetic study on rice photosynthesis and rice breeding for the physiological traits r... Photosynthesis is one of the most important factors that influence the biomass and yield. Recently, more attention has been paid to genetic study on rice photosynthesis and rice breeding for the physiological traits related to high efficient photosynthesis. Chlorophyll content, stomatal resistance, and transpiration rate were very important physiological traits related to photosynthesis. But until now, no genetic study on these traits has been reported. A DH population derived from anther culture of ZYQ8/JX17, a typical indica/japonica hybrid was developed, 展开更多
关键词 rate DH Oryza sativa L QTL analysis of leaf photosynthetic rate and related physiological traits in rice
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Wave growth rate in a cylindrical metal waveguide with ion-channel guiding of a relativistic electron beam
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作者 李海容 唐昌建 王顺金 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期234-241,共8页
This paper addresses the formulae and numerical issues related to the possibility that fast wave may be grown when a relativistic electron beam through an ion channel in a cylindrical metal waveguide. To derive the di... This paper addresses the formulae and numerical issues related to the possibility that fast wave may be grown when a relativistic electron beam through an ion channel in a cylindrical metal waveguide. To derive the dispersion equations of the beam-wave interaction, it solves relativistic Lorentz equation and Maxwell's equations for appropriate boundary conditions. It has been found in this waveguide structure that the TM0m modes are the rational operating modes of coupling between the electromagnetic modes and the betatron modes. The interaction of the dispersion curves of the electromagnetic TM0m modes and the upper betatron modes is studied. The growth rates of the wave are obtained, and the effects of the beam radius, the beam energy, the plasma frequency, and the beam plasma frequency on the wave growth rate are numerically calculated and discussed. 展开更多
关键词 relativistic electron beam PLASMA ion channel dispersion relations wave growth rate
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RELATIVE CALIBRATION OF ^(241)Am FIRE ALARM SOURCE
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作者 冯跟胜 李汉银 《Nuclear Science and Techniques》 SCIE CAS CSCD 1993年第4期251-254,共4页
According to the requirements of improving production of Am source used for smoke-sensitice fire alarm making, a method and equipment of its fast relative calibration have been developed. Six measuring equipments have... According to the requirements of improving production of Am source used for smoke-sensitice fire alarm making, a method and equipment of its fast relative calibration have been developed. Six measuring equipments have being successfully applied at production lines of 241Am fire alarm source and factories of automatic smoke-sensitive fire alarm making. 展开更多
关键词 241Am FIRE ALARM SOURCE a particle emission rate relative CALIBRATION
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USEFUL RELATIVE MOTION DESCRIPTION METHOD FOR PERTURBATIONS ANALYSIS IN SATELLITEFORMATION FLYING
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作者 孟鑫 李俊峰 +1 位作者 高云峰 MA Xing-rui 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第11期1464-1474,共11页
A set of parameters called relative orbital elements were defined to describe the relative motion of the satellites in the formation flying. With the help of these parameters, the effect of the perturbations on the re... A set of parameters called relative orbital elements were defined to describe the relative motion of the satellites in the formation flying. With the help of these parameters, the effect of the perturbations on the relative orbit trajectory and geometric properties of satellite formation can be easily analyzed. First, the relative orbital elements are derived, and pointed out: if the eccentricity of the leading satellite is a small value, the relative orbit trajectory is determined by the intersection between an elliptic cylinder and a plane in the leading satellite orbit frame reference; and the parameters that describe the elliptic cylinder and the plane can be used to obtain the relative orbit trajectory and the relative orbital elements. Second, by analyzing the effects of gravitational perturbations on the relative orbit using the relative orbital elements,it is found that the propagation of a relative orbit consists of two parts : one is the drift of the elliptic cylinder; and the other is the rotation of the plane resulted from the rotation of the normal of the plane. Meanwhile, the analytic formulae for the drift and rotation rates of a relative trajectory under gravitational perturbations are presented. Finally, the relative orbit trajectory and the corresponding changes were analyzed with respect to the J2 perturbation. 展开更多
关键词 satellite formation flying relative orbital element gravitational perturbation drift rate rotation rate
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Study on the Relationships between Utilization Ratios and Conversion Rates of Nitrogen,Phosphorus and Potassium for Maize
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作者 Hongyan ZHENG Ling LU +6 位作者 Xianda HOU Shuojin WANG Zhiping HUANG Jian DING Changhong MI Shutian LIU Yanlin HOU 《Meteorological and Environmental Research》 CAS 2020年第5期69-75,90,共8页
This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for maize by data mining method based on data of"3414 fertilizer field trials"of maiz... This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of maize for plot was that,Y N≈a+b×optimum yield,Y P≈a+b×optimum yield-c×optimum nitrogen application amount-d×optimum potassium application amount,Y K≈a-b×optimum nitrogen application amount-c×temperature in growth season-d×rainfall in growth season,respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships.No significant relationships:22,of which 16 were soil nutrients and 5 were environmental factors,the results showed that soil nutrients and environmental factors had little effect on nutrient conversion rate and fertilizer utilization ratio;consistent significant relationships:14,illustrating that conversion rate and utilization ratio of maize were consistent in most cases,and it was because that maize was planted for a long term,and its fertilizer absorption law was basically stable;contrary significant relationships:0,illustrating that there was no reverse relationship between conversion rate and utilization ratio of maize;complementary significant relationships:18,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the measuring index of fertilizer efficiency in one season,while the nutrient conversion rate was the measuring index of fertilizer efficiency in more seasons.It showed that the fertilizer utilization ratio was significantly correlated,or the nutrient conversion rate was significantly correlated. 展开更多
关键词 Optimum yield Optimum fertilization amount Nutrient conversion rate Fertilizer utilization ratio relative abundance-deficiency value of soil nutrient
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Study on the Relationships between Utilization Ratios and Conversion Rates of Nitrogen,Phosphorus and Potassium for Wheat
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作者 Zhiping HUANG Xianda HOU +6 位作者 Shutian LIU Shuojin WANG Hongyan ZHENG Jian DING Changhong MI Ling LU Yanlin HOU 《Meteorological and Environmental Research》 CAS 2020年第5期46-54,共9页
This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for wheat by data mining method based on data of"3414 fertilizer field trials"of whea... This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for wheat by data mining method based on data of"3414 fertilizer field trials"of wheat by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of wheat for plot was that,Y N≈a+b×optimum nitrogen application amount+c×optimum fertilizer amount of K+d×rainfall in growth season,Y P≈a+b×optimum fertilizer amount of K+c×rainfall in growth season,Y K≈a+b×temperature in growth season+c×rainfall in growth season-d×optimum yield-e×optimum nitrogen application amount,respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships.No significant relationships:13,of which 8 were soil nutrients,the results showed that soil nutrients had little effect on nutrient conversion rate and fertilizer utilization ratio;consistent significant relationships:4,they were all nitrogen and phosphorus,explaining the importance of nitrogen and phosphorus;contrary significant relationships:6,they were all nitrogen and phosphorus,illustrating that phosphorus and nitrogen had inhibitory effect;complementary significant relationships:31,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the measuring index of fertilizer efficiency in one season,while the nutrient conversion rate was the measuring index of fertilizer efficiency in more seasons.It showed that the fertilizer utilization rate was significantly correlated,or the nutrient conversion rate was significantly correlated. 展开更多
关键词 Optimum yield Optimum fertilization amount Nutrient conversion rate Fertilizer utilization ratio relative abundance-deficiency value of soil nutrient
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Study on the Relationship between Utilization Ratios and Conversion Rates of Nitrogen,Phosphorus and Potassium for Rice
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作者 Shuojin WANG Zhiping HUANG +6 位作者 Changhong MI Hongyan ZHENG Jian DING Shutian LIU Xianda HOU Ling LU Yanlin HOU 《Meteorological and Environmental Research》 CAS 2020年第5期25-32,共8页
This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for rice by data mining method based on data of"3414 fertilizer field trials"of rice ... This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for rice by data mining method based on data of"3414 fertilizer field trials"of rice by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of rice for plot was that,Y N≈a+b×optimum yield+c×optimum fertilizer amount of K,Y P≈a+b×optimum yield,Y K≈a respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships:①no significant relationships:25,of which 14 were soil nutrients and 9 were environmental factors,the results showed that soil nutrients and environmental factors had little effect on nutrient yield ratio and fertilizer utilization ratio;②consistent significant relationships:2,one was that yield ratio and utilization ratio of N were positively correlated with the optimum production,explaining the importance of N for production,the other was that yield ratio and utilization ratio of P had a significantly positive correlation with conversion rate and utilization ratio of N,illustrating that nitrogen and phosphorus had mutual promotion;③contrary significant relationships:5,these showed as negative correlations of fertilizer utilization ratio and positive correlation of nutrient conversion ratio;④complementary significant relationships:22,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the index of fertilizer efficiency in one season,while the nutrient conversion rate was the index of fertilizer efficiency in more seasons,which showed that the fertilizer utilization rate was significantly correlated,or the nutrient conversion rate was significantly correlated. 展开更多
关键词 Optimum yield Optimum fertilization amount Nutrient conversion rate Fertilizer utilization ratio relative abundance-deficiency value of soil nutrient
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Cooperation Benefits Both Sides While Confrontation Harms——Thoughts on Strategic Positioning of Sino-U.S. Relations
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作者 Ma Zhengang 《China International Studies》 2006年第1期35-54,共20页
关键词 rate relations Thoughts on Strategic Positioning of Sino-U.S Cooperation Benefits Both Sides While Confrontation Harms
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CRITERION FOR JUDGING SATISFACTION OF CONSISTENCY CONDITIONS IN RATE-DEPENDENT CONSTITUTIVE RELATIONS
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作者 Wang Zhe (College of Civil Engineering and Architecture,Northern Jiaotong University,Beijing 100044,China) 《Acta Mechanica Solida Sinica》 SCIE EI 1999年第4期356-364,共9页
Based on irreversible thermodynamics, the criterion for judging the satisfaction of consistency conditions in rate-dependent constitutive relationship is deduced by introducing four basic hypotheses. Formulas for solv... Based on irreversible thermodynamics, the criterion for judging the satisfaction of consistency conditions in rate-dependent constitutive relationship is deduced by introducing four basic hypotheses. Formulas for solving internal variables are given. It makes the rate-dependent model applicable no matter whether the consistency conditions can be satisfied or not. 展开更多
关键词 rate-dependent constitutive relations consistency condition irreversible thermodynamics
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A GENERAL CONSTITUTIVE RELATION FOR FATIGUE CRACK GROWTH ANALYSIS OF METAL STRUCTURES 被引量:27
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作者 W.C. Cui and X.P. HuangSchool of Naval Architecture & Ocean Engineering, Shanghai Jiaotong University, Shanghai 200030, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2003年第5期342-354,共13页
Crack growth rate curves are the fundamental material property for metal structures under fatigue loading. Although there are many crack growth rate curves available in the literature, few of them showed the capabilit... Crack growth rate curves are the fundamental material property for metal structures under fatigue loading. Although there are many crack growth rate curves available in the literature, few of them showed the capability to explain various special phenomena observed in tests. A modified constitutive relation recently proposed by McEvily and his co-workers showed very promising capability. This modified constitutive relation is further generalized by (1) introducing an unstable fracture condition; (2) defining a virtual strength to replace the yield stress; and (3) defining an overload and underload parameter. The performances of this general constitutive relation for fatigue crack growth is extensively studied and it is found that this general constitutive relation is able to explain various phenomena observed with particular strong capability on load sequence effect. 展开更多
关键词 metal fatigue S-N curve crack growth rate general constitutive relation mean stress effect load sequence effect
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Dynamic Response Analysis of Bird Strike on Aircraft Windshield Based on Damage-modified Nonlinear Viscoelastic Constitutive Relation 被引量:7
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作者 Wang Xinjun Feng Zhenzhou Wang Fusheng Yue Zhufeng 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2007年第6期511-517,共7页
Damage-modified nonlinear viscoelastic constitutive equation and failure criterion are introduced and the three-dimensional incremental forms are deduced based on the updated Lagrangian approach. A simple tensile test... Damage-modified nonlinear viscoelastic constitutive equation and failure criterion are introduced and the three-dimensional incremental forms are deduced based on the updated Lagrangian approach. A simple tensile test model and a split Hopkinson pressure bar model are built to verify the accuracy of the subroutine implemented within the non-linear finite element program LS-DYNA. A numerical model of bird strike on windshield is established to study the responses of windshield under three different bird velocities at three sites. The bird is represented by a cylinder with a hemisphere at each end and the contact-impact coupling algorithm is used in this study. It is found that the implemented subroutine can properly describe the mechanical behavior of polymethyl methaerylate under low and high strain rates and large deformation, and can be used validly. 展开更多
关键词 bird strike damage-modified non-linear viscoelastic constitutive relation material subroutine WINDSHIELD strain rate
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CO_2, H_2O exchange and stomatal regulation of regenerated Camptotheca acuminata plantlets during ex vitro acclimatization 被引量:1
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作者 WANG Hui-mei LI Yan-hua GAO Yin-xiang ZU Yuan-gang 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第4期273-276,共4页
For finding the changes in CO2, H20 exchange and their stomatal regulation during ex vitro acclimatization of regenerated Camptotheca acuminata plantlets, the net photosynthesis rate (Pn), respiration rate (Ro), l... For finding the changes in CO2, H20 exchange and their stomatal regulation during ex vitro acclimatization of regenerated Camptotheca acuminata plantlets, the net photosynthesis rate (Pn), respiration rate (Ro), light compensation point (Lc) and light saturation point (Ls), transpiration rate (Tr), stomatal conductance (gs) and water use efficiency(WUE) were measured during 37 days of ex vitro acclimatization. The results showed that Pn sharply increased until 29 days, then slightly decreased. A substantial decrease in Lc and a substantial increase of Ls in the former two weeks were observed, indicating the light regime enlargement for effective leaf photosynthesis. Tr and gs abruptly decreased during the first week then linearly increased until 29days ex vitro acclimatization, reflecting the strong regulation effect of stomata on water changes of ex vitro acclimating plantlets. Stomatal regulation effect on CO2 exchange was different from that on water exchange, i.e. P, was almost independent of gs during the first week, while P. was significantly correlated with gs thereafter (i.e. dual patterns). Different from dual patterns of gs-Pn relation, the Tr monotonously linearly increased with gs. Furthermore, WUE was almost independent on gs during the first week, while a marked decreasing tendency with gs was found thereafter. At the beginning of the acclimatization, WUE was mainly determined by photosynthetic capacity, while transpiration becomes a main determinant factor for WUE from 7 to 37 days' acclimatization. 展开更多
关键词 Camptotheca acuminate ACCLIMATIZATION Photosynthesis TRANSPIRATION Water use efficiency relation between stomatal conductance (gs) and net photosynthesis rate (Pn) gs-WUE relation
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