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The Impacts of Supplemental Irrigation Based on Soil Moisture Measurement and Nitrogen Use on Winter Wheat Yield and Nitrogen Absorption and Distribution 被引量:4
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作者 Xiukuan JIN Maoting MA +1 位作者 Tongke ZHAO Lingling JIANG 《Asian Agricultural Research》 2017年第8期47-54,共8页
Based on split plot design method of field test,the impacts of supplemental irrigation based on soil moisture measurement and nitrogen use on winter wheat yield and nitrogen absorption and distribution were studied.Su... Based on split plot design method of field test,the impacts of supplemental irrigation based on soil moisture measurement and nitrogen use on winter wheat yield and nitrogen absorption and distribution were studied.Supplemental irrigation had three levels: 60%(W_1),70%(W_2) and 80%(W3) of the targeted relative water content at 0-40 cm of soil layer during jointing period of winter wheat.Nitrogen fertilization had three levels: not using nitrogen(N_0),using pure nitrogen of 195 kg/hm^2(N_(195)) and 255 kg/hm^2(N_(255)).Results showed that:(i)different supplemental irrigation and nitrogen fertilization significantly affected plant height and leaf area of winter wheat during key growth period.Under the same supplemental irrigation treatment,both plant height and leaf area of winter wheat showed as N_(255)> N_(195)> N_0(P <0.05).Plant height in N_(195) and N_(255)treatments was significantly higher than that in N_0 treatment,but there was not significant difference between N_(195) and N_(255)(P >0.05).Under the same nitrogen fertilization,plant height in W_2(569.4 m^3/hm^2) and W3(873.45 m^3/hm^2) treatments was significant higher than that in W_1(265.2 m^3/hm^2),but there was not significant difference between W_2 and W3(P >0.05).It illustrated that excessive nitrogen fertilization and supplemental irrigation did not significantly affect plant height and leaf area of winter wheat.(ii) Under the same nitrogen fertilization level,yield increase effect of winter wheat by supplemental irrigation showed a declining trend with nitrogen application amount increased.It illustrated that nitrogen fertilization and supplemental irrigation had certain critical values on the yield of winter wheat.When surpassing the critical value,the yield declined.When nitrogen fertilization amount was 195 kg/hm^2,and supplemental irrigation amount was 70% of field moisture capacity(569.4 m^3/hm^2),the highest yield 8500 kg/hm^2 could be obtained.(iii) During mature period of winter wheat,nitrogen accumulation amount of plant treated by nitrogen was significantly higher than that not treated by nitrogen(P <0.05).But under the treatments of W_2 and W3,nitrogen accumulation amount in N_(255) significantly declined when compared with N_(195)(P <0.05).Especially under W3(873.45 m^3/hm^2) level,nitrogen accumulation amount in N_(255) was even lower than N_0.Under the treatments of N_0 and N_(195),nitrogen accumulation amount of plant significantly increased with supplemental irrigation increased(P < 0.05).But under N_(255) treatment,there was not significant difference(P > 0.05).It illustrated that moderate supplemental irrigation and nitrogen fertilization could improve nitrogen absorption ability of winter wheat,but excessive supplemental irrigation and nitrogen fertilization were not favorable for plant's nitrogen absorption.(iv) Although the increase of supplemental irrigation during jointing period improved nitrogen absorption ability of winter wheat and promoted winter wheat absorbing more nitrogen,it inhibited nitrogen transferring and distributing to seed.Comprehensively considering growth condition of winter wheat and nitrogen risk condition,it is suggested that nitrogen application amount was 195 kg/hm^2,and supplemental irrigation reached 70% of field moisture capacity(569.4 m^3/hm^2),which could be as the suitable water and fertilizer use amounts in the region. 展开更多
关键词 Winter wheat Supplemental irrigation based on soil moisture measurement Nitrogen application amount YIELD Nitrogen absorption and distribution
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Moisture Absorption and Desorption in an Ionomer-Based Encapsulant:A Type of Self-Breathing Encapsulant for CIGS Thin-Film PV Modules 被引量:2
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作者 Miao Yang Raymund Schäffler +1 位作者 Tobias Repmann Kay Orgassa 《Engineering》 SCIE EI 2020年第12期1403-1407,共5页
As an alternative to conventional encapsulation concepts for a double glass photovoltaic(PV)module,we introduce an innovative ionomer-based multi-layer encapsulant,by which the application of additional edge sealing t... As an alternative to conventional encapsulation concepts for a double glass photovoltaic(PV)module,we introduce an innovative ionomer-based multi-layer encapsulant,by which the application of additional edge sealing to prevent moisture penetration is not required.The spontaneous moisture absorption and desorption of this encapsulant and its raw materials,poly(ethylene-co-acrylic acid)and an ionomer,are analyzed under different climatic conditions in this work.The relative air humidity is thermodynamically the driving force for these inverse processes and determines the corresponding equilibrium moisture content(EMC).Higher air humidity results in a larger EMC.The homogenization of the absorbed water molecules is a diffusion-controlled process,in which temperature plays a dominant role.Nevertheless,the diffusion coefficient at a higher temperature is still relatively low.Hence,under normal climatic conditions for the application of PV modules,we believe that the investigated ionomer-based encapsulant can“breathe”the humidity:During the day,when there is higher relative humidity,it“inhales”(absorbs)moisture and restrains it within the outer edge of the module;then at night,when there is a lower relative humidity,it“exhales”(desorbs)the moisture.In this way,the encapsulant protects the cell from moisture ingress. 展开更多
关键词 IONOMER ENCAPSULANT moisture absorption and desorption Cu(In Ga)Se2 photovoltaic module
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Water Absorption Capcapability and Moisture Content Seasonal Changing of Salt-Crust in Lop Nur Dry Lake
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作者 KONG Deyong LI Baoguo +3 位作者 MA Lichun JIANG Ping'an WU Hongqi LIU Hongpeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期183-184,共2页
The Lop Nur dry salt lake,Xinjiang province,is charactered by typical physiognomy salt-crust,located in39.6-41.3N.latitude and 89.6-91.4E.longitude.The thickness of salt-crust is about from 20 cm to 100 cm,and
关键词 Lop Nur Dry Lake Salt-Crust moisture Content Water absorption Capcapability
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Soil hydraulic conductivity and its influence on soil moisture simulations in the source region of the Yellow River——take Maqu as an example
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作者 DongYu Jia Jun Wen +1 位作者 Xin Wang ZuoLiang Wang 《Research in Cold and Arid Regions》 CSCD 2019年第5期360-370,共11页
Saturated hydraulic conductivity and unsaturated hydraulic conductivity which are influenced by soil are two important factors that affect soil water transport.In this paper,data supplied by the Chinese Academy of Sci... Saturated hydraulic conductivity and unsaturated hydraulic conductivity which are influenced by soil are two important factors that affect soil water transport.In this paper,data supplied by the Chinese Academy of Sciences are used to determine true unsaturated hydrology values.Furthermore,in combination with observed,model simulation and experimental data,an improved saturated hydraulic conductivity parameterization scheme is carried out in CLM4.5 at a single point in the summer.The main results show that:(1)After improving saturated hydraulic conductivity in CLM4.5 through a parameterization modification,it is found that shallow layer soil moisture increases compared to the initial value;and(2)The numerical values of unsaturated hydraulic conductivities in the model are obviously larger than experimental values.By substituting the BrooksCorey soil water characteristic curve into the Mualem model,the value of unsaturated hydraulic conductivity is modified;(3)By using the modified value,it is found that the attenuating magnitude of simulated soil moisture caused by each rainfall event is reduced.The soil moisture variation in shallow layers(5,10 and 20 cm)could be better displayed. 展开更多
关键词 SOIL hydraulic conductivity SOIL moisture source region of the YELLOW River observation
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An Anionic Polymer Incorporating Low Amounts of Hydrophobic Residues Is a Multifunctional Surfactant. Part 1: Emulsifying, Thickening,Moisture-Absorption and Moisture-Retention Abilities of a FattyAcid-Containing Anionic Polysaccharide
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作者 Makoto Urai Tomoko Aizawa +1 位作者 Mutsuyasu Nakajima Michio Sunairi 《Advances in Chemical Engineering and Science》 2015年第2期173-180,共8页
We have been studying the function and structure of fatty acid-containing extracellular polysaccharides (FACEPS) produced by bacteria belonging to the genus Rhodococcus. In this study, we examined the relationships be... We have been studying the function and structure of fatty acid-containing extracellular polysaccharides (FACEPS) produced by bacteria belonging to the genus Rhodococcus. In this study, we examined the relationships between the structure and emulsifying, thickening, moisture-absorption, and moisture-retention capabilities of rhodococcal FACEPS using S-2 EPS produced by R. rhodochrous strain S-2. We prepared chemically deacylated S-2 EPS (DeAcyl S-2 EPS) and palmitoylated DeAcyl S-2 EPS (ReAcyl S-2 EPS), and compared them with native S-2 EPS. All of the properties were attenuated and recovered by deacylation and reacylation of S-2 EPS, respectively. These results suggest that the fatty acid moiety of rhodococcal FACEPS is involved in such functional properties. We also showed that palmitoylation improved the emulsifying, moisture-ab-sorption, and moisture-retention abilities of other acidic polysaccharides that are commercially available. These results suggest that the acidity of the polysaccharide backbone is at least partly responsible for the observed functionality of fatty acid-containing polysaccharides. To our knowledge, this is the first report on multifunctional property of an anionic polymer incorporating low amounts of hydrophobic residues. The present findings could be useful for the creation of new multifunctional surfactants from renewable raw materials for use in various industries, e.g., in cosmetics. 展开更多
关键词 Rhodococcus Fatty Acid-Containing Extracellular POLYSACCHARIDE (FACEPS) Emulsification THICKENING moisture absorption moisture RETENTION
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An Anionic Polymer Incorporating Low Amounts of Hydrophobic Residues Is a Multifunctional Surfactant. Part 2: Emulsification, Moisture Absorption, and Moisture Retention of Alkyl Esterified Poly-γ-Glutamic Acid
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作者 Makoto Urai Tomoko Aizawa +1 位作者 Mutsuyasu Nakajima Michio Sunairi 《Advances in Chemical Engineering and Science》 2015年第2期181-191,共11页
In the accompanying paper (Part 1), we showed that the fatty acid moiety and the acidity of the polysaccharide-backbone of a fatty acid-containing polysaccharide might be involved in its emul-sification, moisture abso... In the accompanying paper (Part 1), we showed that the fatty acid moiety and the acidity of the polysaccharide-backbone of a fatty acid-containing polysaccharide might be involved in its emul-sification, moisture absorption, and moisture retention abilities. In this study, we synthesized alkyl esterified poly-γ-glutamic acid (PGA) with various chain lengths and degrees of substitution of the alkyl moieties to examine how hydrophobic groups incorporated in the anionic polymer contribute to enhanced emulsification, moisture absorption, and moisture retention. With a low degree of alkylation of PGA, these abilities were drastically improved. To improve the moisture absorption of PGA, alkylation with a short chain length is effective in forming interspaces between PGA chains to trap water molecules. Hydrophobic-hydrophilic balance may also be important to improve the emulsification and moisture retention abilities of PGA alkylates. To the best of our knowledge, this is the first report of the relationship between the structure and the multifunctional abilities of an anionic polymer incorporated with a small amount of hydrophobic residue. PGA alkylates, as well as fatty acid-containing polysaccharides, have potential use as multifunctional surfactants throughout various industries. 展开更多
关键词 Poly-γ-Glutamic Acid (PGA) ALKYL ESTER EMULSIFICATION moisture absorption moisture Retention
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Moisture Absorption and Diffusion of a Carbon Composite Structure
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作者 Bing Wang 《Sustainable Marine Structures》 2019年第2期12-18,共7页
Composite materials are lightweight structures and have been wildly used in marine applications.A carbon composite structure usually absorbs moisture while in-service,which can significantly affect its properties,and ... Composite materials are lightweight structures and have been wildly used in marine applications.A carbon composite structure usually absorbs moisture while in-service,which can significantly affect its properties,and detriments the overall performance.We perform a detailed study on moisture absorption and diffusion of a carbon fibre reinforced vinyl ester resin composite system.Composite samples are immersed directly in four different solutions at a temperature of 37±0.5℃for 1444h.The moisture diffusion is analysed through the Fickian diffusion model;the diffusion parameters are subsequently determined from the gravimetric data.The moisture absorption and interaction with the composite constituents are then discussed.These indicate the fundamentals of the moisture absorption and diffusion within the carbon composite structure. 展开更多
关键词 COMPOSITE moisture absorption DEGRADATION Fickian diffusion
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Analysis of the Porosity Changing after Moisture Absorption in Functional Knitted Fabrics
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作者 杜燕峰 沈为 冯勋伟 《Journal of Donghua University(English Edition)》 EI CAS 2007年第6期740-743,共4页
The paper analyses the effect of stitch geometrical modality changing after moisture absorption on the porosity of knitted fabrics,and educes the formulas between porosity and stitch parameters.Regarding as the cell s... The paper analyses the effect of stitch geometrical modality changing after moisture absorption on the porosity of knitted fabrics,and educes the formulas between porosity and stitch parameters.Regarding as the cell stitch,the increasing of yarn diameter brings the porosity decreasing and the fabric shrinking in the wale direction.While the diameter keeps invariability,the yarn elongating brings the fabric humping up as well as the increasing porosity.The air-permeability experiments have been conducted to validate the theoretical analysis,and there is reasonable agreement between the theories and experiments. 展开更多
关键词 功能针织物 几何形态 湿气吸收 空气渗透性
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Moisture Absorption, Mass Loss and Evaporative Resistance of Clothing in Transient Condition
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作者 Chuansi Gao Ingvar Holmr 《Journal of Donghua University(English Edition)》 EI CAS 2006年第5期54-58,共5页
衣服整体的水蒸汽抵抗不是当通常作为干燥热屏蔽决定了。测量技术是更复杂的,测量价值在实验室之中不同。由于通过衣服整体的复杂潮湿转移过程,吸收并且蒸发的潮湿在取决于性质,衣服的厚度,和环境条件的短暂、稳定的州的阶段变化。... 衣服整体的水蒸汽抵抗不是当通常作为干燥热屏蔽决定了。测量技术是更复杂的,测量价值在实验室之中不同。由于通过衣服整体的复杂潮湿转移过程,吸收并且蒸发的潮湿在取决于性质,衣服的厚度,和环境条件的短暂、稳定的州的阶段变化。这研究的 purpse 是在吸湿性的内衣内测量潮湿获得,并且恐水病、可渗透外部作为时间的功能穿,从“皮肤”以及从矮人调查集体损失,成为蒸气的热损失和总数从矮人加热损失确定,并且撕了决定 clothing.Manikin 的水蒸汽抵抗被穿湿“皮肤”模仿出汗的状况使用。在内部服装获得的潮湿内容对时间显示出一种指数的关系。在外部可渗透的层的潮湿显示出小获得。相反,集体损失直接指数地从湿皮肤减少。从矮人的集体损失在整个三个测试阶段是相对稳定的。成为蒸气的热损失关于从出汗的矮人的全部的热损失的 2/3。当与吸湿性的内部服装和可渗透的外部服装测量衣服整体的成为蒸气的抵抗时,对有透不过的外部层的措施整体不同,一小时测量时间是足够的得到相对稳定的结果。在第一小时和第三个小时之间的变化是不到 5% 。短暂时期和测量时间的长度依赖于渗透,衣服整体的厚度和环境条件。 展开更多
关键词 纺织工艺 吸湿方法 蒸汽 纺织技术
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Water Transport Models of Moisture Absorption and Sweat Discharge Yarns
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作者 王发明 周小红 王善元 《Journal of Donghua University(English Edition)》 EI CAS 2008年第5期594-596,共3页
An important property of moisture absorption and sweat discharge yarns is their water transport property. In the paper, two water transport models of moisture absorption and sweat discharge yarns were developed to inv... An important property of moisture absorption and sweat discharge yarns is their water transport property. In the paper, two water transport models of moisture absorption and sweat discharge yarns were developed to investigate the influence factors on their wicking rate. In parallel Column Pores Model, wicking rate is determined by the equivalent capillary radius R and length of the capillary tube L. In Pellets Accumulation Model, wicking rate is decided by the capillary radius r and length of the fiber unit assemble L0. 展开更多
关键词 化学纤维纺织 纺织业 基础科学 理论
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Variability of Soil Moisture and Its Relationship with Surface Albedo and Soil Thermal Parameters over the Loess Plateau 被引量:39
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作者 管晓丹 黄建平 +2 位作者 郭铌 闭建荣 王国印 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第4期692-700,共9页
Data from July 2006 to June 2008 observed at SACOL (Semi-Arid Climate and Environment Observatory of Lanzhou University, 35.946°N, 104.137°E, elev. 1961 m), a semi-arid site in Northwest China, are used to... Data from July 2006 to June 2008 observed at SACOL (Semi-Arid Climate and Environment Observatory of Lanzhou University, 35.946°N, 104.137°E, elev. 1961 m), a semi-arid site in Northwest China, are used to study seasonal variability of soil moisture, along with surface albedo and other soil thermal parameters, such as heat capacity, thermal conductivity and thermal diffusivity, and their relationships to soil moisture content. The results indicate that surface albedo decreases with increases in soil moisture content, showing a typical exponential relation between the surface albedo and the soil moisture. The heat capacity, the soil thermal diffusivity, and soil thermal conductivity show large variations between Julian day 90-212 and 450-578. The soil thermal conductivity is found to increase as a power function of soil moisture. Soil heat capacity and soil thermal diffusivity increase with increases in soil moisture. The SACOL observed soil moisture are also used to validate the AMSR-E/AQUA retrieved soil moisture and there is good agreement between them. The analysis of the relationship between satellite retrieved soil moisture and precipitation suggests that the variability of soil moisture depends on the variation of precipitation over the Loess Plateau. 展开更多
关键词 soil moisture surface albedo soil heat capacity soil thermal conductivity soil thermal diffusivity AMSR-E soil moisture product Loess Plateau
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Relationships Between Surface Albedo,Soil Thermal Parameters and Soil Moisture in the Semi-arid Area of Tongyu,Northeastern China 被引量:30
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作者 刘辉志 王宝民 符淙斌 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第5期757-764,共8页
Continuous observation data collected over the whole year of 2004 on a cropland surtace m Tongyu, a senti-arid area of northeastern China (44°25'N, 122°52'E), have been used to investigate the variations... Continuous observation data collected over the whole year of 2004 on a cropland surtace m Tongyu, a senti-arid area of northeastern China (44°25'N, 122°52'E), have been used to investigate the variations of surface albedo and soil thermal parameters, including heat capacity, thermal conductivity and thermal diffusivity, and their relationships to soil moisture. The diurnal variation of surface albedo appears as a U shape curve on sunny days. Surface albedo decreases with the increase of solar elevation angle, and it tends to be a constant when solar elevation angle is larger than 40°. So the daily average surface albedo was computed using the data when solar elevation angle is larger than 40° Mean daily surface albedo is found to decrease with the increase of soil moisture, showing an exponential dependence on soil moisture. The variations of soil heat capacity are small during Julian days 90 300. Compared with the heat capacity, soil thermal conductivity has very gentle variations during this period, but the soil thermal diffusivity has wide variations during the same period. The soil thermal conductivity is found to increase as a power function of soil moisture. The soil thermal diffusivity increases firstly and then decreases with the increase of soil moisture. 展开更多
关键词 surface albedo soil heat capacity soil thermal conductivity soil thermal diffusivity soil moisture
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The effects of soil moisture and salinity as functions of groundwater depth on wheat growth and yield in coastal saline soils 被引量:3
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作者 ZHANG He LI Yan +5 位作者 MENG Ya-li CAO Nan LI Duan-sheng ZHOU Zhi-guo CHEN Bing-lin DOU Fu-gen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第11期2472-2482,共11页
In the coastal saline soils,moisture and salinity are the functions of groundwater depth affecting crop growth and yield.Accordingly,the objectives of this study were to:1)investigate the combined effects of moisture ... In the coastal saline soils,moisture and salinity are the functions of groundwater depth affecting crop growth and yield.Accordingly,the objectives of this study were to:1)investigate the combined effects of moisture and salinity stresses on wheat growth as affected by groundwater depth,and 2)find the optimal groundwater depth for wheat growth in coastal saline soils.The groundwater depths(0.7,1.1,1.5,1.9,2.3,and 2.7 m during 2013-2014(Y1)and 0.6,1.0,1.4,1.8,2.2,and 2.6 m during 2014-2015(Y2))of the field experiment were maintained by soil columns.There was a positive correlation between soil moisture and salinity.Water logging with high salinity(groundwater depth at 0.7 m in Y1 and 0.6 m in Y2)showed a greater decline towards wheat growth than that of slight drought with medium(2.3 m in Y1)or low salinity(2.7 m in Y1,2.2 and 2.6 m in Y2).The booting stage was the most sensitive stage of wheat crop under moisture and salinity stresses.Data showed the most optimal rate of photosynthesis,grain yield,and flour quality were obtained under the groundwater depth(ditch depth)of 1.9 m(standard soil moisture with medium salinity)and 2.3 m(slight drought with medium salinity)in Y1 and 1.8 m(standard soil moisture with medium salinity)and 2.2 m(slight drought with low salinity)in Y2.The corresponding optimal soil relative moisture content and conductivity with the 1:5 distilled water/soil dilution,in the depth of 0-20 cm and 20-40 cm in coastal saline soils,were equal to 58.67-63.07%and 65.51-72.66%in Y1,63.09-66.70%and 69.75-74.72%in Y2;0.86-1.01 dS m^-1 and 0.63-0.77 dS m^-1 in Y1,0.57-0.93 dS m^-1 and 0.40-0.63 dS m^-1 in Y2,respectively. 展开更多
关键词 COUPLE stress SOIL relative moisture content SOIL conductivity PHOTOSYNTHESIS growth stage
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PRIMARY ANALYSIS ON GROUNDWATER,SOIL MOISTURE AND SALINITY IN FUKANG OASIS OF SOUTHERN JUNGGAR BASIN 被引量:5
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作者 GUFeng-xue ZHANGyuan-dong +2 位作者 CHUYu SHIQing-dong PANXiao-ling 《Chinese Geographical Science》 SCIE CSCD 2002年第4期333-338,共6页
Soil salinity is the most important factor affecting vegetation distribution,and the secondary salinization has affected the development of oasis agriculture.In arid areas the spatial variation of soil moisture and sa... Soil salinity is the most important factor affecting vegetation distribution,and the secondary salinization has affected the development of oasis agriculture.In arid areas the spatial variation of soil moisture and sa lt content is marked-ly affected by groundwater,irratio nal irrigation in artificial oasis.By analyzing the soil moisture,salt content and groundwa-ter table in different areas of old oasis,new oasis and desert in Fukang Oa sis,it is shown that topography and l and use are main factors affecting the change of groundwater table,the redistribution of soil moisture and salt cont ent.When undis-turbed by human,the groundwater tab le rises from mountain to belt of grou nd water spillage,the groundwater t able rises mightily in plain because of the artificial irrigation,and the secondary salinization of soil is very seriou s.In oasis the ground-water table raises compared with that in the natural desert at the same latitude.In old oasis of upper reaches o f river salt has not been concentrated too much in rhizosphere because this area is the belt of groundwater drainage,soil t exture is coarse,the groundwater table is very low,and the salt in soil is drained i nto the groundwater.The new oasis has been the areas of salt accumulation becau se of the artificial irrigation,the salt content in soil is higher than th at in old oasis,so some cultivated fields here had to be thrown out because of the serious s econdary salinization. 展开更多
关键词 绿洲 盐份 地下水 土地湿度
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Moisture Detection of SF_6 Gas Instruments by Solid Electrolyte
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作者 Eiichi Nagao Tadao Minagawa +1 位作者 Chieko Nishida Mitsuhito Kamei 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期353-356,共4页
Humidity measurement in a very low moisture atmosphere was studied by using solid electrolyte film coated with porous electrodes,considering its application to the moisture monitoring of SF_6 gas-insulated high voltag... Humidity measurement in a very low moisture atmosphere was studied by using solid electrolyte film coated with porous electrodes,considering its application to the moisture monitoring of SF_6 gas-insulated high voltage instruments such as gas-insulated switchgear (GIS) and gas circuit breakers (GCBs).Compared to the AC impedance values measured in an ambient atmosphere where the moisture atmosphere is far higher than that in these instruments,considerably large impedance values were obtained in a very low moisture atmosphere.The impedance was systematically measured in accordance with the conditions of these instruments whose moisture contents were less than 1 000×10^(-6).A good correlation was obtained between the impedance values and the moisture contents.The frequency characteristics of the impedance were analyzed based on a conventional equivalent circuit where a number of CR circuits were connected in series.Considering the dielectric relaxation of each circuit,it was found that the frequency characteristics of the impedance can be explained by the equivalent circuit. Two semicircles were clearly obtained in the Cole-Cole impedance plot which are thought to reflect the impedance characteristics of the film and the electrodes.The AC impedance can be a good indicator of the moisture content of SF_6 gas-insulated high voltage instruments. 展开更多
关键词 humidity moisture solid electrolyte IMPEDANCE ion conductivity
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Moisture Distribution of Heterogeneous Agglomerates in Fluidized Bed
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作者 Zhou Yunlong Yang Ning Miao Yanan 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第1期117-124,共8页
Agglomerates formed in the fluidized bed were studied in this paper using the TEB atomization nozzle. The multi-sieving method was adopted to distinguish the size of original particles, nucleation agglomerates, cohere... Agglomerates formed in the fluidized bed were studied in this paper using the TEB atomization nozzle. The multi-sieving method was adopted to distinguish the size of original particles, nucleation agglomerates, coherence agglomerates, and paste agglomerates in order to successfully identify the different growth stages and select the region for coexistence of most stable heterogeneous agglomerates as the research object. A multi-channel conductance electrical circuit experimental device was developed in this study to measure the conductance signal, which was found to have a liner relationship with the moisture content inside the fluidized bed. By adjusting the sieve mesh openings to achieve the layered isolation of heterogeneous agglomerates, the conductance signal recovered slowly as a result of the agglomerates' fracture during the continuous fluidization process, so that particles and agglomerates moisture distribution measurements could be implemented. The device was used to measure the particles and agglomerates moisture distribution state in the heterogeneous coexistence region, when they were injected with liquid mass within the range of w i=2.8 kg to 4.4 kg. The results indicated that with the increase of liquid mass flow, the moisture content of coherence agglomerates also increased, but the moisture content of nucleation agglomerates was decreased, and that of the original particles was maintained at a relatively low level. When the experimental injection amount reached 4.4 kg, the moisture contained in coherence agglomerates could amount to 87.3%, accounting for a big percentage of moisture in the fluidized bed. 展开更多
关键词 AGGLOMERATES conductANCE signal FRACTURE moisture content
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INVESTIGATION OF THE CHARACTERISTICS OF DYNAMIC HEAT AND MOISTURE TRANSMISSIONS THROUGH FABRICS
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作者 严灏景 钱军 《Journal of China Textile University(English Edition)》 EI CAS 1994年第2期11-18,共8页
In this paper, the dynamic heat and moisture transmissions through fabrics are investigated, and their interaction manner is discussed. The essentials of the apparatus developed for measuring the amount of heat flow t... In this paper, the dynamic heat and moisture transmissions through fabrics are investigated, and their interaction manner is discussed. The essentials of the apparatus developed for measuring the amount of heat flow through fabrics during the whole period of simulated sweating action is reported. The registered heat flow flux in a continuous curve form covering the complete dry-wet-dry cycle of the sample is presented. Interpretation of the feature of the curve and indexes for characterizing the wearing comfort property of fabrics are suggested. 展开更多
关键词 FABRICS FABRIC property moisture GRADIENT HEAT conductivity HEAT measurement.
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Methodology for Determination of Moisture Distribution
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作者 J. Skramlik M. Novotny K. Suhajda 《Journal of Chemistry and Chemical Engineering》 2012年第8期715-720,共6页
关键词 水分分布 测定方法 多孔材料 实验测量 毛细管力 微波辐射 非破坏性 导热系数
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The Moisturein Capillaries of Building Materials
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作者 Jan Skramlik Miloslav Novotny Karel Suhajda 《Journal of Civil Engineering and Architecture》 2012年第11期1536-1543,共8页
关键词 建材 毛细血管 热传导系数 建筑材料 水分影响 土木结构 实验基础 绝缘性能
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High Moisture Sensitivity of the Elements Based on Carbon Nanotubes Array
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作者 Sergei Bulyarsky Vyacheslav Galperin +3 位作者 Levan Ichkitidze Michael Ermakov Alexander Pavlov Yuri Shaman 《Materials Sciences and Applications》 2013年第5期8-10,共3页
The results of the research and development of the moisture-sensitive elements based on the carbon nanotubes (CNT) array are presented. It was shown that CNT arrays that were grown by low-temperature plasma enhanced c... The results of the research and development of the moisture-sensitive elements based on the carbon nanotubes (CNT) array are presented. It was shown that CNT arrays that were grown by low-temperature plasma enhanced chemical vapor deposition (PECVD) method on the planar Si structures exhibit extremely high moisture sensitivity. The structure resistance ratio in dry and moisture conditions exceed 400. Such relatively high change in resistances is conditioned by the pattern of change of the charge carrier’s conductivity between certain nanotubes in the bundle when water molecules adsorption occurs. 展开更多
关键词 Carbon NANOTUBES moisture-Sensitive ELEMENTS conductivity MOLECULES Adsorption
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