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用MetriScan^(TM)骨密度仪测量西双版纳、西藏、内蒙古地区健康人群骨密度的情况调查分析 被引量:6
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作者 高国一 杨玲 +4 位作者 姜范波 王威 平措扎西 阿叁次仁 汪建 《中国骨质疏松杂志》 CAS CSCD 2008年第12期875-879,共5页
目的应用放射吸收法测量云南西双版纳、西藏和内蒙古三个少数民族地区,对傣族、藏族和蒙古族健康人群的骨量分布差异和峰值骨量进行调查分析,为临床诊断骨质疏松提供参考。方法选择云南西双版纳傣族健康男女1126名,年龄20~79岁。西藏... 目的应用放射吸收法测量云南西双版纳、西藏和内蒙古三个少数民族地区,对傣族、藏族和蒙古族健康人群的骨量分布差异和峰值骨量进行调查分析,为临床诊断骨质疏松提供参考。方法选择云南西双版纳傣族健康男女1126名,年龄20~79岁。西藏藏族健康男女1531名,年龄20~79岁。内蒙东乌旗蒙古族健康男女901名,年龄20~79岁。以10岁为一年龄段进行分组。用美国Alara公司提供的MetriscanTM指骨骨密度仪,进行骨密度测量。数据采用SPSS软件包进行统计学分析。结果西双版纳傣族男女、西藏藏族男女和内蒙古东乌旗蒙古族女性的峰值骨年龄段均在30~39岁,蒙古族男性峰值骨年龄段在40~49岁。傣族和藏族男性骨量丢失12%以上在60~69岁年龄段,蒙古族男性70~79年龄段骨量丢失11.04%。傣族女性50~59岁年龄段骨量丢失达20.80%,藏族女性为13.67%。蒙古族女性丢失12%以上在60~69岁年龄段。三个民族不同年龄段骨密度值比较,男性除藏族和蒙古族20~39岁年龄段没有差异外,其余各年龄段均有显著性差异。女性除傣族和藏族20~29岁年龄段没有差异外,其余各年龄段均有显著性差异。结论健康成人傣族男性与藏族和蒙古族健康成人男性相比骨密度有显著差异,藏族和蒙古族男性40岁以后骨密度均值有显著性差异。傣族女性与蒙古族女性各年龄段骨密度均有显著性差异,傣族与藏族女性30岁后骨密度有显著性差异。其差异是种族、地域,还是生活习性引起有待进一步研究。 展开更多
关键词 骨密度值 民族 健康人群 丢失百分率 Metriscan^TM骨密度仪
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A study on the simulation of carbon and water fluxes of Dangxiong alpine meadow and its response to climate change 被引量:1
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作者 Lingyun He Lei Zhong +3 位作者 Yaoming Ma Yuting Qi Jie Liu Peizhen Li 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期22-27,共6页
The alpine meadow ecosystem accounts for 27%of the total area of the Tibetan Plateau and is also one of the most important vegetation types.The Dangxiong alpine meadow ecosystem,located in the south-central part of th... The alpine meadow ecosystem accounts for 27%of the total area of the Tibetan Plateau and is also one of the most important vegetation types.The Dangxiong alpine meadow ecosystem,located in the south-central part of the Tibetan Plateau,is a typical example.To understand the carbon and water fluxes,water use efficiency(WUE),and their responses to future climate change for the alpine meadow ecosystem in the Dangxiong area,two parameter estimation methods,the Model-independent Parameter Estimation(PEST)and the Dynamic Dimensions Search(DDS),were used to optimize the Biome-BGC model.Then,the gross primary productivity(GPP)and evapotranspiration(ET)were simulated.The results show that the DDS parameter calibration method has a better performance.The annual GPP and ET show an increasing trend,while the WUE shows a decreasing trend.Meanwhile,ET and GPP reach their peaks in July and August,respectively,and WUE shows a“dual-peak”pattern,reaching peaks in May and November.Furthermore,according to the simulation results for the next nearly 100 years,the ensemble average GPP and ET exhibit a significant increasing trend,and the growth rate under the SSP5–8.5 scenario is greater than that under the SSP2–4.5 scenario.WUE shows an increasing trend under the SSP2–4.5 scenario and a significant increasing trend under the SSP5–8.5 scenario.This study has important scientific significance for carbon and water cycle prediction and vegetation ecological protection on the Tibetan Plateau. 展开更多
关键词 Carbon and water flux Water use efficiency Alpine meadow Biome-BGC model Climate change
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内蒙古东乌珠穆沁旗蒙古族正常人群骨密度测量结果分析 被引量:5
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作者 高国一 姜范波 +4 位作者 杨玲 平措扎西 华桑 李奎 汪建 《内蒙古医学院学报》 2009年第5期445-447,456,共4页
目的:研究内蒙古东乌珠穆沁旗地区蒙古族正常人群骨量分布情况,确定峰值骨量,分析其年龄段变化规律。为本地区制定骨质疏松诊断标准提供科学依据。方法:选择内蒙古东乌珠穆沁旗蒙古族健康男女901名,年龄为20-79岁。以10岁为一年龄段,... 目的:研究内蒙古东乌珠穆沁旗地区蒙古族正常人群骨量分布情况,确定峰值骨量,分析其年龄段变化规律。为本地区制定骨质疏松诊断标准提供科学依据。方法:选择内蒙古东乌珠穆沁旗蒙古族健康男女901名,年龄为20-79岁。以10岁为一年龄段,对男女分别进行分组。用美国Alara公司提供的MetriscanTM指骨骨密度仪,对非习惯性用手的第2、3、4手指进行测量,取三个手指的平均骨密度值。数据采用SPSS11.0软件进行统计学分析。结果:内蒙古东乌珠穆沁旗蒙古族女性峰值骨量在30-39岁年龄段,男性在40-49岁年龄段。女性60-69岁年龄段骨量丢失15.01%,在70-79岁年龄段骨量丢失21.09%,达2.328SD;男性在70-79岁年龄段骨量丢失11.04%。男女峰值骨密度分别为0.3994g/cm3和0.3776g/cm3。男性各年龄段骨密度值均高于女性。结论:放射吸收法测量内蒙古东乌珠穆沁旗地区健康人群峰值骨量和骨量丢失规律符合骨质疏松流行病学发病率,但晚于国内相关报道。本研究结果为内蒙古蒙古族骨密度研究提供了参考数据和资料。 展开更多
关键词 骨密度值 健康人群 丢失百分率 Metriscan骨密度仪
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数形结合量率合一:有效突破分数概念教学难点
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作者 戚彩红 《新一代(理论版)》 2022年第4期148-150,共3页
分数是小学阶段“数的认识”领域中较难教学的一个概念,学生对分数关于量和率的意义存在理解障碍。笔者从“分物图示”入手,“数、形、式结合”,运用“均分”“除法”感知分数是“分”出来的、沟通分数与除法的内在联系,运用“图示”让... 分数是小学阶段“数的认识”领域中较难教学的一个概念,学生对分数关于量和率的意义存在理解障碍。笔者从“分物图示”入手,“数、形、式结合”,运用“均分”“除法”感知分数是“分”出来的、沟通分数与除法的内在联系,运用“图示”让学生经历分数“部分份数”与“整体份数”的关系,感知分数是“比”出来的,“量”和“率”有机统一,全面理解分数的意义,促进学生由具体形象思维向抽象思维转化。 展开更多
关键词 图示教学 分数的意义 分率
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共聚物组成及其控制 被引量:2
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作者 赵殊 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2013年第11期164-167,共4页
共聚合在理论研究和在生产实践中都具有重要的意义,共聚物组成及其控制是最重要的内容,其中有一些难点需要深入解析。文中在推导中引入竞聚率,得到共聚物组成的(物质的)量比微分方程、(物质的)量分率微分方程及质量分率微分方程;解释共... 共聚合在理论研究和在生产实践中都具有重要的意义,共聚物组成及其控制是最重要的内容,其中有一些难点需要深入解析。文中在推导中引入竞聚率,得到共聚物组成的(物质的)量比微分方程、(物质的)量分率微分方程及质量分率微分方程;解释共聚的类型及意义;介绍计算关键点(f1,F1)绘制共聚物组成曲线简图的方法;由共聚物组成的积分方程绘图来解释共聚物组成的控制方法及原理。 展开更多
关键词 共聚物组成 竞聚率 量分率 量分率 微分方程 积分方程 组成曲线 组成控制
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Effect of Slow and Controlled Release Fertilizers on the Yield and Nutrient Use Efficiency of Hot Pepper in Qiu-bei 被引量:8
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作者 杜彩艳 段宗颜 +2 位作者 鲁耀 胡万里 陈拾华 《Agricultural Science & Technology》 CAS 2011年第5期761-764,共4页
[Objective] The aim of this study was to investigate the impacts of slow and controlled release fertilizers(SCRF)on the yield of qiubei hot pepper,its nutrient use efficiency and environment.[Method] Using Qiubei ho... [Objective] The aim of this study was to investigate the impacts of slow and controlled release fertilizers(SCRF)on the yield of qiubei hot pepper,its nutrient use efficiency and environment.[Method] Using Qiubei hot pepper(Capsicum frutescens L.)as the experimental material,we studied the fertilization effect and environment-protecting effect of SCRF.[Result] The result showed that SCRF could improve the agronomic characteristics of hot pepper.Compared to singly applied common fertilizers,SCRF increased economic yield by 20.90% and economic benefit by 13 234.35 Yuan/hm2,and the ratio of output to input was improved by 47.93%.In comparison with common straight fertilizers at same NPK proportion and rate,SCRF increased economic yield by 5.26% and economic benefit by 5 554.80 Yuan/hm2,and the ratio of output to input was improved by 9.91%.Under the reduced use of SCRF by 20%,SCRF increased economic yield by 12.38% and economic benefit by 9595.20 Yuan/hm2 compared with singly applied common fertilizers,and the ratio of output to input was improved by 65.95%.SCRF improved nitrogen,phosphorus and potassium use efficiencies by 12.42-17.53,3.35-5.24 and 5.37-14.02 percents respectively.[Conclusion] As the result of much reduced N and P application rates,SCRF would significantly economize fertilizer resources and minimize the pollution caused by the loss of fertilizer nutrients,which is of practical importance for environment protection. 展开更多
关键词 Slow and controlled release fertilizer Qiubei hot pepper YIELD Nutrient use efficiency
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Effect of Different Irrigation Maximums on Absorption and Utilization of Water in Chinese Kale 被引量:3
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作者 曹健 张白鸽 +1 位作者 宋钊 罗少波 《Agricultural Science & Technology》 CAS 2016年第2期344-346,408,共4页
[Objective] This study was conducted to investigate the effect of soil moisture on the growth and water utilization of Chinese kale. [Method] The law of water absorption and utilization of Chinese kale was researched ... [Objective] This study was conducted to investigate the effect of soil moisture on the growth and water utilization of Chinese kale. [Method] The law of water absorption and utilization of Chinese kale was researched under the same irri- gation frequency and different irrigation maximums. [Result] Soil water deficit re- duced water contents in plants in seedling stage and in plants and various organs in maturation stage; water consumption of individual plant was the lowest in 55% treatment of soil A and 45% treatment of soil B, which showed the values of 2.244 and 2.235 L/plant, respectively, and saved water by 23.91% and 21.14% compared with CK; water use efficiencies of soil A with a water content of 55% and soil B with a water content of 35% were the highest, i.e., 6.043 and 5.958 g/L, which were higher than that of CK by 20.09% and 41.72%, respectively; and regulated deficit irrigation also improved irrigation water productivity, and the two kinds of soil both showed in 75% treatments the highest irrigation water productivities, i.e., 40.44 and 40.49 g/L, which were higher than that of CK by 5.64% and 13.39%, respec- tively. [Conclusion[ Controlling irrigation maximum could save water consumed by Chinese kale, improve water use efficiency and improve yield and quality. 展开更多
关键词 Chinese kale Soil water IRRIGATION
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Effects of Slow Release Fertilizer on the Yield and Nutrient Use Efficiency of Carnation and Its Environmental Protection Effect 被引量:4
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作者 杜彩艳 段宗颜 +1 位作者 胡万里 陈拾华 《Agricultural Science & Technology》 CAS 2011年第4期571-575,共5页
[Objective] The aim was to study the effects of slow release fertilizer on the yield,economic benefit and nutrient use efficiency of carnation and environmental pollution.[Method] Taking carnation(Dianthus caryophyl... [Objective] The aim was to study the effects of slow release fertilizer on the yield,economic benefit and nutrient use efficiency of carnation and environmental pollution.[Method] Taking carnation(Dianthus caryophyllus)as research object,the application effect and environmental protection effect of slow release fertilizer on carnation were discussed through field plot test.[Result] The main agronomic characters of carnation improved after the application of slow release fertilizer;compared with Conv-F treatment,the yield of carnation with slow release fertilizer increased by 18.67%-20.83%,and its economic benefit increased by 105 500 yuan/hm2,while the ratio of output to input improved by 74.29%;under the same NPK ratio and nutrient amount,the yield,economic benefit and ratio of output to input of carnation after the application of slow release fertilizer increased by 2.11%,14 800 yuan and 16.2%,respectively;besides,the application of slow release fertilizer improved the nutrient use efficiency of carnation,and N,P and K nutrient use efficiency in Opt-F-0.7% treatment increased by 13.88%,8.57% and 30.14% compared with Conv-F treatment.[Conclusion] Slow release fertilizer could not only reduce the waste of fertilizer resources and improve fertilizer use efficiency but also decrease the pollution caused by nutrient loss,which had important practical significance for protecting ecological environment and promoting the sustainable development of agriculture. 展开更多
关键词 Slow release fertilizer CARNATION YIELD Nutrient use efficiency Environmental protection effect
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Antisepsis and Fresh-keeping Effects of Natamycin Coating Compounds Treatment on Red Global Grape 被引量:3
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作者 周会玲 刘美迎 +2 位作者 任小林 吴主莲 张维 《Agricultural Science & Technology》 CAS 2012年第9期2012-2016,2036,共6页
The aim was to research fresh-keeping effects of natamycin on cold-pre- served grape. Red globe grapes were processed with compound coating liquid of chitosan with mass fraction at 1% and natamycin with mass fractions... The aim was to research fresh-keeping effects of natamycin on cold-pre- served grape. Red globe grapes were processed with compound coating liquid of chitosan with mass fraction at 1% and natamycin with mass fractions at 0.20% (T1), 0.40% (T2) and 0.60% (T3), respectively. Grapes processed with water (CK3) and 1% chitosan (CK2) were taken as control groups. Rotten rate, seed shattering rate, mass loss rate, respiratory intensity and related physiological quality in test and control groups were compared. The results indicated that respiratory intensity, mass loss rate, rotten rate and seed shattering rate in CK1 were all higher than those in CK2. In addition, T1, T2 and T3 were lower in the indices than CK1 and CK2, but still kept at a high level in fruit hardness. Furthermore, mass fractions of Vc and titratable acid declined more slowly in T1, T2 and T3, compared with CK1 and CK2. Natamycin better preserved grapes and prolonged storage period. In general, natamycin with mass fraction at 0.4% proved best in fresh-keeping. 展开更多
关键词 NATAMYCIN CHITOSAN Red global grape ANTISEPSIS Fresh-keeping
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High resolution GPR and its experimental study 被引量:2
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作者 黄玲 曾昭发 +1 位作者 王牧男 王者江 《Applied Geophysics》 SCIE CSCD 2007年第4期301-307,共7页
We develop a high resolution ground penetrating radar system (LANRCS-GPR) based on the E5071B Vector Network Analyzer (VNA). This system takes advantage of a wideband and adjustable frequency domain ground penetra... We develop a high resolution ground penetrating radar system (LANRCS-GPR) based on the E5071B Vector Network Analyzer (VNA). This system takes advantage of a wideband and adjustable frequency domain ground penetrating radar system and adds the characteristics of a network analyzer with ultra-wideband and high precision measurement. It adopts the LAN mode to concatenate system control that reduces construction cost and makes the system easy to expand. The high resolution ground penetrating radar system carries out real time imaging using F-K migration with high calculation efficiency. The experiment results of the system indicate that the LANRCS-GPR system provides high resolution and precision, high signal-to-noise ratio, and great dynamic range. Furthermore, the LANRCS-GPR system is flexible and reliable to operate with easy to expand system functions. The research and development of the LANRCS-GPR provide the theoretical and experimental foundation for future frequency domain ground penetrating radar production and also can serve as an experimental platform with high data gathering precision, enormous information capability, wide application, and convenient operation for electromagnetic wave research and electromagnetic exploration. 展开更多
关键词 high resolution ground penetrating radar vector network analyzer and frequency domain
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Application of the equivalent offset migration method in acoustic log reflection imaging 被引量:6
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作者 张铁轩 陶果 +2 位作者 李君君 王兵 王华 《Applied Geophysics》 SCIE CSCD 2009年第4期303-310,393,共9页
Borehole acoustic reflection logging can provide high resolution images of nearborehole geological structure. However, the conventional seismic migration and imaging methods are not effective because the reflected wav... Borehole acoustic reflection logging can provide high resolution images of nearborehole geological structure. However, the conventional seismic migration and imaging methods are not effective because the reflected waves are interfered with the dominant borehole-guided modes and there are only eight receiving channels per shot available for stacking. In this paper, we apply an equivalent offset migration method based on wave scattering theory to process the acoustic reflection imaging log data from both numerical modeling and recorded field data. The result shows that, compared with the routine post-stack depth migration method, the equivalent offset migration method results in higher stack fold and is more effective for near-borehole structural imaging with low SNR acoustic reflection log data. 展开更多
关键词 acoustic reflection logging common scatter point gather signal processing nearborehole structure imaging
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Improved spatial resolution in soil moisture retrieval at arid mining area using apparent thermal inertia 被引量:4
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作者 雷少刚 卞正富 +1 位作者 John L.DANIELS 刘东烈 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第6期1866-1873,共8页
A surface soil moisture model with improved spatial resolution was developed using remotely sensed apparent thermal inertia(ATI).The model integrates the surface temperature derived from TM/ETM+ image and the mean ... A surface soil moisture model with improved spatial resolution was developed using remotely sensed apparent thermal inertia(ATI).The model integrates the surface temperature derived from TM/ETM+ image and the mean surface temperature from MODIS images to improve the spatial resolution of soil temperature difference based on the heat conduction equation,which is necessary to calculate the ATI.Consequently,the spatial resolution of ATI and SMC can be enhanced from 1 km to 120 m(TM) or 60m(ETM+).Moreover,the enhanced ATI has a much stronger correlation coefficient(R^2) with SMC(0.789) than the surface reflectance(0.108) or the ATI derived only from MODIS images(0.264).Based on the regression statistics of the field SMC measurement and enhanced ATI,a linear regression model with an RMS error of 1.90%was found. 展开更多
关键词 soil water content soil temperature difference thermal inertia remote sensing spatial resolution
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Effects of Sand Burial on the Survival, Growth, and Biomass Allocation in Semi-shrub Hedysarum laeve Seedlings 被引量:14
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作者 张称意 于飞海 董鸣 《Acta Botanica Sinica》 CSCD 2002年第3期337-343,共7页
Hedysarum laeve Maxim. (Leguminosae) is one of the major species used frequently in revegetation of dune_field in the sandlands of the northern part of China by means of aerial sowing. Seedlings of the species after e... Hedysarum laeve Maxim. (Leguminosae) is one of the major species used frequently in revegetation of dune_field in the sandlands of the northern part of China by means of aerial sowing. Seedlings of the species after emergence above the sand surface may be buried in sand to various depths during its establishment in late spring and early summer. A study was made to examine the effects of sand burial at different levels of 0 (control), 33%, 67%, 100% and 133% of their shoot height, on the survivorship, growth, and biomass allocation pattern of H. laeve seedlings (one and two weeks old after emergence). When burial depth was up to 100% of their shoot height, about 70% seedlings died; and the burial at depth of 133% of their shoot height led to death of all seedlings. When seedlings was buried at depth of 33% and 67% of their shoot height, respectively, after six_week growth, their biomass of whole plant, blade, and root and relative growth rate were higher than the unburied counterparts. The seedlings in both 33% and 67% sand burial treatments did not significantly change their biomass allocation pattern comparing with the unburied ones. Furthermore, the number of leaves and shoot height of the seedlings in both 33% and 67% sand burial treatments were not significantly different from those of unburied individuals, respectively. The newly born leaves of the surviving seedlings, in 33%, 67%, and 100% burial treatments, during the period of experiment, were significantly more than those in control. 展开更多
关键词 Hedysarum laeve sandland sand burial SEEDLING GROWTH SURVIVAL biomass allocation relative growth rate
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Effects of Different Tillage Techniques on Yield and Water Use Efficiency in Broomcorn Millet 被引量:2
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作者 陈凌 乔治军 +6 位作者 王君杰 王海岗 曹晓宁 田翔 刘思辰 秦慧彬 杨光宗 《Agricultural Science & Technology》 CAS 2017年第3期432-434,437,共4页
[Objective] The effects of different tillage techniques on dry matter accu- mulation, soil water content, water use efficiency and yield of broomcom millet were studied. [Method] With Jinsu 9 as an experiment material... [Objective] The effects of different tillage techniques on dry matter accu- mulation, soil water content, water use efficiency and yield of broomcom millet were studied. [Method] With Jinsu 9 as an experiment material, the effects of deep tillage, traditional tillage and no tillage and rotary tillage on dry matter accumulation, soil water content, water use efficiency and yield of broomcom millet were investi- gated. [Result] Dry matter accumulation rate and accumulated amount were signifi- cantly higher in the deep tillage, no tillage and rotary tillage treatments than in the conventional tillage treatment, and the highest in the deep tillage treatment. The soil water content of the deep tillage treatment at 0-100 cm was higher than those of other tillage techniques, deep tillage also exhibited the highest soil water storage, and water use efficiency values were in order of deep tillage〉rotary tillage〉no tillage〉conventional tillage. The deep tillage treatment also showed the highest grain weight per spike, 1 000-grain weight and yield, while conventional tillage exhibited the lowest values, indicating that deep tillage is most beneficial to improvement of yield and water use efficiency of broomcom millet. [Conclusion] This study provides a scientific basis for water use efficiency of broomcorh millet in its main producing areas. 展开更多
关键词 Tillage techniques Broomcorn Millet Water use efficiency YIELD
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Effect of Surface Potential Barrier on the Electron Energy Distribution of NEA Photocathodes
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作者 邹继军 杨智 +2 位作者 乔建良 常本康 曾一平 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第8期1479-1483,共5页
By calculating the energy distribution of electrons reaching the photocathode surface and solving the Schrodinger equation that describes the behavior of an electron tunneling through the surface potential barrier,we ... By calculating the energy distribution of electrons reaching the photocathode surface and solving the Schrodinger equation that describes the behavior of an electron tunneling through the surface potential barrier,we obtain an equation to calculate the emitted electron energy distribution of transmission-mode NEA GaAs photocathodes. Accord- ing to the equation,we study the effect of cathode surface potential barrier on the electron energy distribution and find a significant effect of the barrier-Ⅰ thickness or end height,especially the thickness,on the quantum efficiency of the cath- ode. Barrier Ⅱ has an effect on the electron energy spread, and an increase in the vacuum level will lead to a narrower electron energy spread while sacrificing a certain amount of cathode quantum efficiency. The equation is also used to fit the measured electron energy distribution curve of the transmission-mode cathode and the parameters of the surface barri- er are obtained from the fitting. The theoretical curve is in good agreement with the experimental curve. 展开更多
关键词 NEA photocathode surface potential barrier transmission coefficient electron energy distribution quantum efficiency
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Effects of Different Management Modes on Yield and Nutrient Efficiency of Ginger
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作者 郑福丽 张柏松 +4 位作者 高燕 田叶 马征 谭德水 江丽华 《Agricultural Science & Technology》 CAS 2015年第6期1222-1226,共5页
In order to establish high-yield and high-efficient cultivation technology for ginger in the central region of Shandong Province, the effects of different manage-ment modes on yield of ginger, nutrient efficiency and ... In order to establish high-yield and high-efficient cultivation technology for ginger in the central region of Shandong Province, the effects of different manage-ment modes on yield of ginger, nutrient efficiency and soil nitrate were carried out by field experiment. Four management modes were farmer convention mode, high yield and high efficiency mode, super high yield mode and super high yield and high efficiency mode, in which farmer convention mode was local farmers ’ conven-tional cropping methods, the other three management modes were optimized combi-nations of al management measures under a certain goal of increasing yield and efficiency. The results were as fol ows: ginger yield and nitrogen fertilizer efficiency under such three optimized management measures combinations as high yield and high efficiency mode, super high yield mode and super high yield and high efficien-cy mode were al higher than these of farmer convention mode, moreover, com-pared with farmer convention mode, the yield increased by 11.85%, 25.75% and 23.34%, respectively, and nitrogen fertilizer efficiency increased by 47.94%, 11.24%and 33.14%, respectively. Thereinto, the yield under super high yield mode were the greatest,and nitrogen fertilizer efficiency under high yield and high efficiency mode was the highest. 展开更多
关键词 Different management modes GINGER YIELD Nutrient efficiency
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Effects of Different Irrigation Amounts on Water Consumption and Water Use Efficiency of Greenhouse Cucumber 被引量:6
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作者 郭生虎 孔德杰 +2 位作者 张源沛 郑国宝 朱金霞 《Agricultural Science & Technology》 CAS 2010年第9期217-220,共4页
[Objective] This study was to investigate the effects of different irrigation amount on water consumption and water use efficiency of greenhouse cucumber.[Method]Under the condition of drip irrigation with different w... [Objective] This study was to investigate the effects of different irrigation amount on water consumption and water use efficiency of greenhouse cucumber.[Method]Under the condition of drip irrigation with different water amounts in sunlight greenhouse of the arid areas in Ningxia,the soil water was measured and the water consumption of crop was calculated.[Result]When irrigation amount was 563 mm,the water consumption as a whole gradually increased with the delay of growth period,reached peak during the thriving stage of fruit setting,and then gradually declined;in each treatment,the daily water consumption increased with the increasing of irrigation amount during each growth period.However,the consumption of soil moisture reduced with the significant increase of irrigation.563 mm of irrigation amount could meet the water requirements of cucumber and began to add water to soil,and water utilization efficiency could reach 33.4 kg/m3.[Conclusion]The research had provided theoretical basis for water management in the production process of greenhouse cucumber. 展开更多
关键词 GREENHOUSE CUCUMBER Irrigation amount Water consumption Water utilization efficiency
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Nutrient Limiting Factor and Agronomic Efficiency of Wheat in Fluvo-aquic Soil District in Northwest of Shandong Province 被引量:1
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作者 马征 魏建林 +4 位作者 郭洪海 张柏松 董晓霞 徐长英 崔荣宗 《Agricultural Science & Technology》 CAS 2013年第8期1191-1194,共4页
[Objective] This study aimed to provide basis for rational fertilizer application of wheat in fluvo-aquic soil in the northwest of Shandong Province.[Method] In this paper,the treatments of reduced N,P and K were set ... [Objective] This study aimed to provide basis for rational fertilizer application of wheat in fluvo-aquic soil in the northwest of Shandong Province.[Method] In this paper,the treatments of reduced N,P and K were set in order to explore the effects of fertilizer recommendation based on ASI systematic approach on wheat yield,agronomic efficiency and recovery rate of nutrients.[Result] Nitrogen was the main limiting factor for wheat production in that area,followed by phosphorus,and the third was potassium.Compared with the optimum treatment (OPT),the reduction of N,P and K reduced the grain yield obviously,which came up to 22.4%,14.4% and 13.4% respectively.There were no obvious differences in grain yield among Farmer's Fertilization Practice (FP),60% OPT-N and OPT treatment.[Conclusion] Agronomic efficiency of N,P and K was 6.3,12.9 and 10 kg/kg respectively.The recovery rates of N,P and K in wheat season were 16.41%,17.27% and 27.27% respectively. 展开更多
关键词 WHEAT Fluvo-aquic soil YIELD Nutrient limiting factor Agronomic efficiency
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Effect of Continuous Application of Controlled Release Nitrogen Fertilizer in Various Types of Soil in Dong-Ting Lake Region under Double Rice Cropping System
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作者 鲁艳红 廖育林 +3 位作者 聂军 谢坚 杨曾平 戴平安 《Agricultural Science & Technology》 CAS 2012年第2期351-356,379,共7页
[Objective] This study aimed to explore the effects of continuous application of controlled release nitrogen fertilizer under double rice cropping system. [Method] By modeling three types of paddy soils in Dong-Ting L... [Objective] This study aimed to explore the effects of continuous application of controlled release nitrogen fertilizer under double rice cropping system. [Method] By modeling three types of paddy soils in Dong-Ting Lake area, four treatments as no fertilizer (CK), urea, controlled release nitrogen fertilizer (CRNF) and 70% controlled release nitrogen fertilizer (70% CRNF) were designed in the micro-plot trials from 2005 to 2008. [Result] The rice yield in treatment CRNF at N 150 kg/hm2 was increased by 10.3%, 8.0% and 2.4% compared with treatment of urea, in alluvial sandy loamy paddy soil (ALS), purple calcareous clayey paddy soil (PCS), and reddish yellow loamy paddy soil (RYS), respectively; and the yield in treatment of 70% CRNF was increased by 6.1%, 2.6% and -0.8%, respectively. The ranking order of nitrogen uptake amount by plant in early rice and late rice was CRNF 70% CRNF urea CK in all three types of soil. Nitrogen utilization efficiency of CRNF in above three types of soil was 60.7%, 59.6% and 56.3%, increased by 23.8%, 19.4% and 16.3% compared with that in treatment of urea, respectively. Nitrogen utilization efficiency of CRNF in early rice was increased year by year, and was higher than that of 70% CRNF during the whole experiment stage, while that in late rice was increased first and then decreased from the 3rd year. [Conclusion] Continuous application CRNF could alleviate the decreasing of soil nitrogen fertility and organic carbon especially in ALS, increase rice yield and nitrogen utilization efficiency in double-rice cropping system. 展开更多
关键词 Double cropping rice Controlled release nitrogen fertilizer Continuous fertilization YIELD Fertilizer use efficiency Soil fertility
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Effects of Different Irrigation Amounts on Water Consumption and Water Use Efficiency of Dripirrigated Celery
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作者 杨军 廉晓娟 +2 位作者 王艳 张余良 王正祥 《Agricultural Science & Technology》 CAS 2016年第9期2090-2095,共6页
This study aimed to investigate the effects of different irrigation amounts on water consumption and water use efficiency of celery under the condition of drip irrigation, so as to provide a scientific basis for high-... This study aimed to investigate the effects of different irrigation amounts on water consumption and water use efficiency of celery under the condition of drip irrigation, so as to provide a scientific basis for high-yielding, high-quality and highefficiency cultivation and water-saving irrigation of greenhouse celery. Total five irrigation amounts were designed, 117.5 (T1), 160.0 (T2), 202.5 (T3), 245.0 (T4) and 287.5 (CK) mm/hm2, and the effects of different irrigation amounts on yield, water consumption and water use efficiency of celery were studied by plot experiment. The results showed that at the soil depth of 0-40 cm, the soil water storages of different treatments ranked as T3's〉T4's〉CK's〉T2's〉T1's, and the celery water consumptions ranked as CK's〉T4's〉T3's〉T2's〉T1's. At the same time, the soil water storage in different treatment group declined with the growth of celery, and finally increased at the harvest period. Among different irrigation amounts, the water use effi- ciency and irrigation water use efficiency all ranked as T1's〉T2's〉T3's〉T4's〉CK's. The water consumption of celery was positively related to irrigation amount (P〈 0.01), and was negatively related to water use efficiency (P〈0.01) and irrigation water use efficiency (P〈0.05). When the irrigation amount was below 253 mm/hm2, the celery yield was positively related to irrigation amount (P〈0.01). There was also a positive correlation between celery output and irrigation amount. Compared with those of CK, the benefit of the T4 treatment group was equal, and the water consumption was reduced by 14.78%. In high-efficiency solar greenhouse, the irrigation amount of drip-irrigated celery is recommended as 245 mm/hm2. 展开更多
关键词 Drip irrigation CELERY Irrigation amount Water consumption Water use efficiency
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