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反义复合词“高低”的语法化及动因分析
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作者 任美颐 《现代语言学》 2024年第6期272-277,共6页
“高低”是一个现代汉语常见的反义复合词,有名词和副词两种词性。从一个并列结构的词组发展到名词再到副词,“高低”的语法化演变有着一脉相承的演化轨迹。副词“高低”的形成有着隐喻和转喻的认知基础,并且跟语义的泛化与虚化、语境... “高低”是一个现代汉语常见的反义复合词,有名词和副词两种词性。从一个并列结构的词组发展到名词再到副词,“高低”的语法化演变有着一脉相承的演化轨迹。副词“高低”的形成有着隐喻和转喻的认知基础,并且跟语义的泛化与虚化、语境的影响有着密切的关系。 展开更多
关键词 反义复合词 “高低” 语法化 认知分析
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“高低”的言者态度立场及主观性分析 被引量:1
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作者 朱敏 《湖州师范学院学报》 2021年第9期111-116,共6页
在语言沟通中,言者使用情态副词“高低”表达强调、感慨、立誓、告诫等立场功能。“高低”的历时演变过程也是其语法化、主观化的过程。在此过程中,言者频繁使用“高低”来表达自己的主观意愿,情态副词“高低”的主观性逐渐加强,在人们... 在语言沟通中,言者使用情态副词“高低”表达强调、感慨、立誓、告诫等立场功能。“高低”的历时演变过程也是其语法化、主观化的过程。在此过程中,言者频繁使用“高低”来表达自己的主观意愿,情态副词“高低”的主观性逐渐加强,在人们的交际互动中成为言者表达立场的态度立场标记。 展开更多
关键词 情态副词 “高低” 语法化 主观化 态度立场标记
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临汾方言表指责口气的“X高低哩(吧)”
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作者 任淑宁 《汉字汉语研究》 2021年第4期85-95,128,共12页
反义对立式语气副词"高低"在临汾方言中有三个义项:无论如何;真是的;终究,总算。其可分别称为"高低_(1)""高低_(2)""高低_(3)"。临汾方言中"X高低哩(吧)"表指责口气,其中"高低&... 反义对立式语气副词"高低"在临汾方言中有三个义项:无论如何;真是的;终究,总算。其可分别称为"高低_(1)""高低_(2)""高低_(3)"。临汾方言中"X高低哩(吧)"表指责口气,其中"高低"的意思与"真是的"相近,是临汾方言中所特有的,属于"高低_(2)"。本文以反预期理论和言语行为理论为基础,认为"高低_(1)"具有反预期功能,可表示建议、劝告、指责等语用意义。"高低_(2)"是在"高低_(1)"的基础上发展变化而来的,语义范围缩小,语义更为明确,专表指责义。新的结构"X高低哩(吧)"的产生导致了"高低"意义的变化,形成了"高低_(2)",而"X高低哩(吧)"则是句法省略的结果。 展开更多
关键词 临汾方言 指责口气 反预期
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阜阳方言语气副词“高低(kɔ^(213)ti^(24))”语法化研究
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作者 尚永云 《阜阳职业技术学院学报》 2021年第4期79-83,共5页
阜阳方言的“高低”是一个高频语气副词,可以表示“无论如何”和“到底、终究”两种语法意义。语气副词“高低”的语法化过程经历了3个阶段:即形容词词组阶段、名词阶段、语气副词阶段。极性对立的两个语素融合虚化表周遍性语义是“高... 阜阳方言的“高低”是一个高频语气副词,可以表示“无论如何”和“到底、终究”两种语法意义。语气副词“高低”的语法化过程经历了3个阶段:即形容词词组阶段、名词阶段、语气副词阶段。极性对立的两个语素融合虚化表周遍性语义是“高低”语法化的语义基础,双音化趋势和句法位置改变是“高低”语法化的条件,口语语境是“高低”语气副词属性强化的推动机制。 展开更多
关键词 阜阳方言 语气副词 “高低”(kɔ^(213)ti^(24)) 语法化
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运用“高低”“低高”突破等值线复习难点
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作者 庞立 《高中生地理》 2003年第2期51-54,共4页
关键词 “高低” “低高” 等值线 复习难点 高中 地理 教学 复习
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High density dislocations enhance creep ageing response and mechanical properties in 2195 alloy sheet
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作者 WEI Shuo MA Pei-pei +3 位作者 CHEN Long-hui YANG Jian-shi ZHAN Li-hua LIU Chun-hui 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2194-2209,共16页
The creep strain of conventionally treated 2195 alloy is very low,increasing the difficulty of manufacturing Al-Cu-Li alloy sheet parts by creep age forming.Therefore,finding a solution to improve the creep formabilit... The creep strain of conventionally treated 2195 alloy is very low,increasing the difficulty of manufacturing Al-Cu-Li alloy sheet parts by creep age forming.Therefore,finding a solution to improve the creep formability of Al-Cu-Li alloy is vital.A thorough comparison of the effects of cryo-deformation and ambient temperature large pre-deformation(LPD)on the creep ageing response in the 2195 alloy sheet at 160℃with different stresses has been made.The evolution of dislocations and precipitates during creep ageing of LPD alloys are revealed by X-ray diffraction and transmission electron microscopy.High-quality 2195 alloy sheet largely pre-deformed by 80%without edge-cracking is obtained by cryo-rolling at liquid nitrogen temperature,while severe edge-cracking occurs during room temperature rolling.The creep formability and strength of the 2195 alloy are both enhanced by introducing pre-existing dislocations with a density over 1.4×10^(15)m^(−2).At 160℃and 150 MPa,creep strain and creep-aged strength generally increases by 4−6 times and 30−50 MPa in the LPD sample,respectively,compared to conventional T3 alloy counterpart.The elongation of creep-aged LPD sample is low but remains relevant for application.The high-density dislocations,though existing in the form of dislocation tangles,promote the formation of refined T1 precipitates with a uniform dispersion. 展开更多
关键词 creep ageing Al-Cu-Li alloy high dislocation density cryogenic rolling dislocation strengthening
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形式逻辑与辩证逻辑:从“对立说”、“高低说”、“主从说”到“协同说”
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作者 余奎 《科教导刊(电子版)》 2013年第28期154-155,共2页
文章梳理了学界关于形式逻辑和辩证逻辑关系的三种代表性观点:“对立说”、“高低说”和“主从说”,指出了各自的合理性和片面性,最后提出自己的见解:“协同说”,强调对形式逻辑和辩证逻辑关系的理解,不能只从形式上区分,而要从... 文章梳理了学界关于形式逻辑和辩证逻辑关系的三种代表性观点:“对立说”、“高低说”和“主从说”,指出了各自的合理性和片面性,最后提出自己的见解:“协同说”,强调对形式逻辑和辩证逻辑关系的理解,不能只从形式上区分,而要从本质和功能上深化认识,并在实践中使二者相互结合、协同运用。 展开更多
关键词 形式逻辑 辩证逻辑 “对立说” “高低说” “主从说” “协同说”
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Multiplexer Design Applied to High-Speed Signal Transmission 被引量:2
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作者 曹寒梅 杨银堂 +2 位作者 蔡伟 陆铁军 王宗民 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第6期1040-1043,共4页
A multiplexer with a low-distortion high-bandwidth analog switch is presented. The gate-to-source voltage of the switch is set by the combined on-voltage of a pMOS and an nMOS,and the difference between its gate-sourc... A multiplexer with a low-distortion high-bandwidth analog switch is presented. The gate-to-source voltage of the switch is set by the combined on-voltage of a pMOS and an nMOS,and the difference between its gate-source voltage and the threshold voltage (VGST) is guaranteed to be constant with input variation. Thus, the body effect is nearly canceled. Implemented in a TSMC 0.18μm CMOS process, results from HSPICE simulation show that the VGST is nearly constant with an input range from 0.3 to 1.7V,and the - 3dB bandwidth is larger than 10GHz;the SFDR (spurious free dynamic range) of the output is 67. lldB with 1GHz input frequency; the turn-on time is 2.98ns,and the turn-off time is 1.35ns, which indicates a break-before-make action of the multiplexer. The proposed structure can be applied to high speed signal transmission. 展开更多
关键词 low-distortion high speed MULTIPLEXER analog switch
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GaAs PIN Diodes for X-Band Low Loss and High Isolation Switches 被引量:1
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作者 吴茹菲 张海英 +3 位作者 尹军舰 张健 刘会东 刘训春 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第5期832-835,共4页
GaAs PIN diodes optimized for X-band low loss and high isolation switch application are presented. The impact of diode physical characteristics and electrical parameters on switch performance is discussed. A new struc... GaAs PIN diodes optimized for X-band low loss and high isolation switch application are presented. The impact of diode physical characteristics and electrical parameters on switch performance is discussed. A new structure for GaAs PIN diodes is proposed and the fabrication process is described. GaAs PIN diodes with an on-state resistance of 〈2. 2Ω and off-state capacitance -〈20fF in the range of 100MHz to 12.1GHz are obtained. 展开更多
关键词 GaAs PIN diodes LOW-LOSS high-isolation SWITCH
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ULTRASTRUCTURE OF THE VEGETATIVE CELLS OF NOSTOC FLAGELLIFORME PREPARED WITH HIGH PRESSURE FREEZING AND FREEZE SUBSTITUTION TECHNIQUE 被引量:8
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作者 祝建 王俊 +1 位作者 华振基 马丁.米勒 《Acta Botanica Sinica》 CSCD 1998年第10期901-905,共5页
The ultrastructure of the vegetative cells of Nostoc flagelliforme Born. et Flah. was investigated with high pressure freezing and freeze substitution technique and compared with the results obtained by using conv... The ultrastructure of the vegetative cells of Nostoc flagelliforme Born. et Flah. was investigated with high pressure freezing and freeze substitution technique and compared with the results obtained by using conventional preparation methods. During the processes of chemical fixation, dehydration and embedding, the cell structures might be more artificially modified than that obtained from high pressure freezing and freeze substitution. With the present method, the sheath of N. flagelliforme could be well penetrated and no extra big space could exist between the cell and the sheath. The cell protoplasm rarely shrinked. Some fine structures of cell inclusions and unit membranes became visualized. Many bacteria were harbored in the sheath. In addition, the presence of big vacuoles in the cell of N. flagelliforme as well as the presence of bacteria in the sheath shown in the present preparation for cyanobacteria has not been described so far in the literature. 展开更多
关键词 ULTRASTRUCTURE Nostoc flagelliforme Vegetative cell High pressure freezing Freeze substitution
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Ultrasonic method for measuring water holdup of low velocity and high-water-cut oil-water two-phase flow 被引量:2
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作者 赵安 韩云峰 +2 位作者 任英玉 翟路生 金宁德 《Applied Geophysics》 SCIE CSCD 2016年第1期179-193,222,共16页
Oil reservoirs with low permeability and porosity that are in the middle and late exploitation periods in China's onshore oil fields are mostly in the high-water-cut production stage.This stage is associated with sev... Oil reservoirs with low permeability and porosity that are in the middle and late exploitation periods in China's onshore oil fields are mostly in the high-water-cut production stage.This stage is associated with severely non-uniform local-velocity flow profiles and dispersed-phase concentration(of oil droplets) in oil-water two-phase flow,which makes it difficult to measure water holdup in oil wells.In this study,we use an ultrasonic method based on a transmission-type sensor in oil-water two-phase flow to measure water holdup in lowvelocity and high water-cut conditions.First,we optimize the excitation frequency of the ultrasonic sensor by calculating the sensitivity of the ultrasonic field using the finite element method for multiphysics coupling.Then we calculate the change trend of sound pressure level attenuation ratio with the increase in oil holdup to verify the feasibility of the employed diameter for the ultrasonic sensor.Based on the results,we then investigate the effects of oildroplet diameter and distribution on the ultrasonic field.To further understand the measurement characteristics of the ultrasonic sensor,we perform a flow loop test on vertical upward oilwater two-phase flow and measure the responses of the optimized ultrasonic sensor.The results show that the ultrasonic sensor yields poor resolution for a dispersed oil slug in water flow(D OS/W flow),but the resolution is favorable for dispersed oil in water flow(D O/W flow) and very fine dispersed oil in water flow(VFD O/W flow).This research demonstrates the potential application of a pulsed-transmission ultrasonic method for measuring the fraction of individual components in oil-water two-phase flow with a low mixture velocity and high water cut. 展开更多
关键词 Oil-water two-phase flow low mixture velocity high water cut ultrasonic sensor water holdup
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Analysis and Design of a Quadrature Down-Conversion Mixer for UHF RFID Readers 被引量:3
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作者 倪熔华 谈熙 +1 位作者 唐长文 闵昊 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第6期1128-1135,共8页
A quadrature mixer with a shared transconductor stage is analyzed,including voltage conversion gain, linearity, noise figure, and image rejection. The analysis indicates it has better performance than a conventional G... A quadrature mixer with a shared transconductor stage is analyzed,including voltage conversion gain, linearity, noise figure, and image rejection. The analysis indicates it has better performance than a conventional Gilbert mixer pair in commutating mode. A quadrature down-conversion mixer based on this topology is designed and optimized for an ultra high frequency RFID reader. Operating in the 915MHz ISM band, the presented quadrature mixer measures a conversion gain of 12.5dB,an IIP3 of 10dBm, an IIP2 of 58dBm, and an SSB noise figure of 17.6riB. The chip was fabricated in a 0. 18μm 1P6M RF CMOS process and consumes only 3mA of current from a 1.8V power supply. 展开更多
关键词 quadrature mixer shared transconductor stage RFID reader CMOS low power high linearity
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Molecular Cloning the Gene of Small Heat Shock Protein in the Mitochondria and Endoplasmic Reticulum of Tomato 被引量:17
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作者 刘箭 庄野真理子 《Acta Botanica Sinica》 CSCD 2001年第2期138-145,共8页
A cDNA Library was constructed with the heat shocked tomato ( Lycopersicon esculentum Mill.) flowers and then was screened with the probes of mitochondrial and endoplasmic reticulum conservative regions that were clon... A cDNA Library was constructed with the heat shocked tomato ( Lycopersicon esculentum Mill.) flowers and then was screened with the probes of mitochondrial and endoplasmic reticulum conservative regions that were cloned by using RT-PCR. The complete cDNAs of mitochondrial and endoplasmic reticulum small heat shock protein ( shsp) were selected out from the cDNA library. Furthermore, the temperature responses of these shsp genes were determined. Northern hybridization showed that the heat response temperatures of both genes in tomato flower were lower than that in leaf and that mitochondria shsp in leaf was cold-inducible. In this paper, the molecular features of the cloned genes, the causes of the uncommon heat response temperatures of sHSP in newer and the cold inducible character of mitochondria shsp gene in leaf were discussed. 展开更多
关键词 Lycopersicon esculentum small heat shock protein MITOCHONDRIA endoplasmic reticulum high temperature stress low temperature stress
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Production of super-high strength aluminum alloy billets by low frequency electromagnetic casting 被引量:6
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作者 张海涛 崔建忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第10期2134-2139,共6页
The effects of low frequency electromagnetic field on the macro-physical fields in the semi-continuous casting process of aluminum alloys and the microstructure and crack in the billets were studied and analyzed by th... The effects of low frequency electromagnetic field on the macro-physical fields in the semi-continuous casting process of aluminum alloys and the microstructure and crack in the billets were studied and analyzed by the numerical and experimental methods.Comparison of the results for the macro-physical fields in the low frequency electromagnetic casting(LFEC) process with the conventional DC casting process indicates the following characters due to the application of electromagnetic field:an entirely changed direction and remarkably increased velocity of melt flow;a uniform distribution and a decreased gradient of temperature;elevated isothermal lines;a reduced sump depth;decreased stress and plastic deformation.Further,the microstructure of the billets is refined remarkably and the crack in the billets is eliminated in LFEC process because of modification of the macro-physical fields induced by the application of low frequency electromagnetic field. 展开更多
关键词 super-high strength aluminum alloy low frequency electromagnetic casting DC casting macro-physical field CRACK MICROSTRUCTURE
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Noise filtering of full-gravity gradient tensor data 被引量:8
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作者 袁园 黄大年 +1 位作者 余青露 耿美霞 《Applied Geophysics》 SCIE CSCD 2013年第3期241-250,357,共11页
In oil and mineral exploration, gravity gradient tensor data include higher- frequency signals than gravity data, which can be used to delineate small-scale anomalies. However, full-tensor gradiometry (FTG) data are... In oil and mineral exploration, gravity gradient tensor data include higher- frequency signals than gravity data, which can be used to delineate small-scale anomalies. However, full-tensor gradiometry (FTG) data are contaminated by high-frequency random noise. The separation of noise from high-frequency signals is one of the most challenging tasks in processing of gravity gradient tensor data. We first derive the Cartesian equations of gravity gradient tensors under the constraint of the Laplace equation and the expression for the gravitational potential, and then we use the Cartesian equations to fit the measured gradient tensor data by using optimal linear inversion and remove the noise from the measured data. Based on model tests, we confirm that not only this method removes the high- frequency random noise but also enhances the weak anomaly signals masked by the noise. Compared with traditional low-pass filtering methods, this method avoids removing noise by sacrificing resolution. Finally, we apply our method to real gravity gradient tensor data acquired by Bell Geospace for the Vinton Dome at the Texas-Louisiana border. 展开更多
关键词 Gravity gradient tensor Laplace equation optimal linear inversion low-passfilter high frequency signal
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A Low-Power High-Frequency CMOS Peak Detector
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作者 李学初 高清运 秦世才 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第10期1707-1710,共4页
A low-power,high-frequency CMOS peak detector is proposed. This detector can detect RF signal and base-band signal peaks. The circuit is designed using SMIC 0.35μm standard CMOS technology. Both theoretical calculati... A low-power,high-frequency CMOS peak detector is proposed. This detector can detect RF signal and base-band signal peaks. The circuit is designed using SMIC 0.35μm standard CMOS technology. Both theoretical calculations and post simulations show that the detection error is no more than 2% for various temperatures and processes when the input amplitude is larger than 400mV. The detection bandwidth is up to 10GHz, and its static current dissipation is less than 20μA. 展开更多
关键词 CMOS peak detector lower power high frequency
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Grain refinement of as-cast superalloy IN718 under action of low voltage pulsed magnetic field 被引量:13
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作者 李应举 马晓平 杨院生 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第6期1277-1282,共6页
The grain refinement of superalloy IN718 under the action of low voltage pulsed magnetic field was investigated. The experimental results show that fine equiaxed grains are acquired under the action of low voltage pul... The grain refinement of superalloy IN718 under the action of low voltage pulsed magnetic field was investigated. The experimental results show that fine equiaxed grains are acquired under the action of low voltage pulsed magnetic field. The refinement effect of the pulsed magnetic field is affected by the melt cooling rate and superheating. The decrease of cooling rate and superheating enhance the refinement effect of the low voltage pulsed magnetic field. The magnetic force and the melt flow during solidification are modeled and simulated to reveal the grain refinement mechanism. It is considered that the melt convection caused by the pulsed magnetic field, as well as cooling rate and superheating contributes to the refinement of solidified grains. 展开更多
关键词 SUPERALLOY grain refinement low voltage pulsed magnetic field cooling rate SUPERHEATING
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Interpretation of 850 hPa Temperature in Temperature Forecast of Jiamusi Area 被引量:1
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作者 尹嫦姣 孙洪伟 《Agricultural Science & Technology》 CAS 2017年第4期660-664,共5页
Based on the initial field temperature data of ECMWF 850 hPa from Jan- uary 2012 to December 2015, linear interpolation method of ECMWF was employed to calculate the 850 hPa temperature values at 8:00 and 20:00 of 7... Based on the initial field temperature data of ECMWF 850 hPa from Jan- uary 2012 to December 2015, linear interpolation method of ECMWF was employed to calculate the 850 hPa temperature values at 8:00 and 20:00 of 7 stations (Jiamusi, Tangyuan, Huachuan, Huanan, Fujin, Tongjiang, Fuyuan). Combined with the observed daily minimum and maximum air temperatures at the same time of the 7 stations, the correlations of the 850 hPa temperature values at 8:00 and 20:00 with the daily maximum or minimum air temperature of the ground meteorological obser- vation stations were established, and the ground observation data in accordance with the relevant analysis and correlation test principle of the prediction equation for factor were primarily selected. Regression method was used to establish forecast e- quation dividing into counties, month by month. The results showed that the 850 hPa temperature values at 8:00 and 20:00 were significantly correlated with the daily maximum or minimum air temperature, and the established temperature fore- cast equation was of certain guiding significance for the forecast of daily minimum and maximum temperature, which could help to improve the forecast accuracy. 展开更多
关键词 850 hPa temperature Daily air temperature Regression equation Cor- relation
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Differentiation of Barley Genotypes with High Phosphorus Efficiency under Low Phosphorus Stress 被引量:2
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作者 杨涛 何金宝 +3 位作者 曾亚文 普晓英 杨树明 杜娟 《Agricultural Science & Technology》 CAS 2013年第11期1615-1619,共5页
[Objective] This study aimed to investigate differences in phosphorus effi-ciency between two-rowed barley and multiple-rowed barley and differences in phos-phorus efficiency among various agronomic traits, and to exp... [Objective] This study aimed to investigate differences in phosphorus effi-ciency between two-rowed barley and multiple-rowed barley and differences in phos-phorus efficiency among various agronomic traits, and to explore the relationship be-tween agronomic traits and row type with phosphorus efficiency. [Method] Under available phosphorus mass fractions of 1.32 and 36.6 mg/kg, 172 barley varieties, including 79 two-rowed foreign barley, 22 multiple-rowed foreign barley, 58 two-rowed Chinese barley and 13 multiple-rowed Chinese barley, were selected to com-pare differences in phosphorus efficiency-related agronomic traits. Plant height, spike length, number of unfil ed grains, number of unfil ed grains, main panicle weight, to-tal panicle weight, total stem weight, weight of aerial part and heading stage were surveyed for statistical analysis. [Result] The results showed that, various agronomic traits were larger under fertilization condition than under non-fertilization condition ex-cept number of unfil ed grains and heading stage. Plant high, spike length, weight of aerial part and heading stage varied greatly under non-fertilization condition; number of fil ed grains, number of unfil ed grains and total stem weight varied greatly under fertilization condition. In two-rowed barley, plant height and number of fil ed grains of Chinese varieties were higher than those of foreign varieties, while other agronomic traits such as spike length, number of unfil ed grains, main panicle weight, total panicle weight, total stem weight, weight of aerial part and heading stage of foreign varieties were higher than those of Chinese varieties. Spike length and weight of aerial part in multiple-rowed and two-rowed foreign barley were higher than those in Chinese barley. In multiple-rowed barley, plant height, number of unfil ed grains, total panicle weight and total stem weight of foreign varieties were higher under non-fer-tilization condition and lower under fertilization condition compared with those of Chi-nese varieties; number of fil ed grains, main panicle weight and heading stage of foreign varieties were lower under non-fertilization condition and higher under fertil-ization condition compared with those of Chinese varieties. [Conclusion] Heading stage, number of fil ed grains, number of unfil ed grains and total stem weight are more sensitive to phosphorus efficiency. Multiple-rowed barley is more sensitive to phosphorus efficiency than two-rowed barley. 展开更多
关键词 Low phosphorus stress BARLEY High phosphorus efficiency GENOTYPE Agronomic traits
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我国中原至华北平原冬季雾-霾与北半球大气环流异常 被引量:4
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作者 王洁 王继志 +3 位作者 王宏 陈怀亮 杨元琴 张梦 《气象与环境科学》 2017年第4期1-8,共8页
采用2000—2017年1月地面和高空观测基本气象要素(气压、温度、湿度、风、能见度和雾-霾天气现象等)观测信息、1980—2016年1月NCEP再分析资料等,基于气候平均态的环流异常特征分析,发展对平均气候态出现异常变化的综合诊断分析方法,研... 采用2000—2017年1月地面和高空观测基本气象要素(气压、温度、湿度、风、能见度和雾-霾天气现象等)观测信息、1980—2016年1月NCEP再分析资料等,基于气候平均态的环流异常特征分析,发展对平均气候态出现异常变化的综合诊断分析方法,研究华北地区冬季典型雾-霾多寡年大气环流的三维结构及其遥相关异常特征。结果表明:2000—2017年冬季1月,华北平原、中原等黄河中下游地区冬季雾-霾的发生日数呈增加趋势,雾-霾发生日数线性增加拟合趋势相关确认系数为R2=0.36,超过0.001的显著性水平。基于气候平均态环流异常特征分析表明,华北平原、中原等黄河中下游地区雾-霾污染出现多、寡年的对流层大气大尺度环流分布差异显著。气候平均态的环流异常特征分析表明,多雾-霾年,在冬季1月影响中国的冷空气主要路径上,自极地区泰米尔半岛,经中西伯利亚、贝加尔湖地区到中国东部区域,对流层中层与高层位势高度距平呈现"高—低—高"的分布,在低层则出现"东高西低"的气候平均态异常分布;少雾-霾年,该分布型不复存在,并出现反位相特征。多雾-霾年的这种异常环流分布型可为中原至华北平原冬季雾-霾的频发提供有利的气候背景,是该区域冬季雾-霾多发的重要原因。 展开更多
关键词 中原与华北平原 冬季雾-霾 北半球环流 对流层环流三维结构 “高低高”距平分布
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