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复方醋酸钠林格注射液中无水葡萄糖含量测定方法的建立及葡萄糖转化现象的探讨
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作者 章娟 石颖 +1 位作者 邱娟 李玮玲 《广东药科大学学报》 CAS 2023年第4期14-19,共6页
目的建立复方醋酸钠林格注射液中无水葡萄糖含量测定方法,并针对方法建立中发现的葡萄糖转化问题开展研究。方法采用氨基硅烷键合硅胶为填充剂的色谱柱;以乙腈-水-氨水(体积比75∶25∶0.1)为流动相;示差折光检测器检测;流速为1.0 mL/min... 目的建立复方醋酸钠林格注射液中无水葡萄糖含量测定方法,并针对方法建立中发现的葡萄糖转化问题开展研究。方法采用氨基硅烷键合硅胶为填充剂的色谱柱;以乙腈-水-氨水(体积比75∶25∶0.1)为流动相;示差折光检测器检测;流速为1.0 mL/min,柱温和检测池温度均为40℃。结果无水葡萄糖浓度在0.4125~8.249 mg/mL范围内线性关系良好(r=1.0000),定量限为101μg/L,平均回收率为100.5%,RSD为0.5%,采用该测定法发现样品中少量葡萄糖转化为果糖。结论建立的方法简单、准确、灵敏度高,不受葡萄糖转化现象的干扰,适用于复方醋酸钠林格注射液中无水葡萄糖的含量测定。 展开更多
关键词 复方醋酸钠林格注射液 无水葡萄糖 葡萄糖转化
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基于含水层-钻孔水量交换的疏水钻孔水量计算 被引量:9
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作者 刘基 靳德武 王皓 《煤炭学报》 EI CAS CSCD 北大核心 2021年第9期2995-3005,共11页
疏水降压是煤矿顶板水害防治的主要工程手段,复合充水含水层中倾斜疏放水钻孔涌水量计算及参数优化是需要解决的关键技术。以“渗流-管流耦合模型”理论及能量守恒定律为基础,以含水层-钻孔间水量交换量为耦合点,构建了煤层顶板复合充... 疏水降压是煤矿顶板水害防治的主要工程手段,复合充水含水层中倾斜疏放水钻孔涌水量计算及参数优化是需要解决的关键技术。以“渗流-管流耦合模型”理论及能量守恒定律为基础,以含水层-钻孔间水量交换量为耦合点,构建了煤层顶板复合充水含水层倾斜疏放水钻孔定降深放水的含水层-钻孔系统耦合模型,利用母杜柴登矿井临时煤仓放水试验数据验证了模型的可靠性。以此为基础,计算了不同钻孔仰角、数量的钻孔涌水量及单位长度涌水量,确定了钻孔的最佳仰角和数量。同时,计算分析了150 m钻场间距下600 m工作面范围内不同疏降水头的钻孔涌水量、工作面内部降深的特征。结果表明:基于含水层-钻孔水量交换的疏放水钻孔水量计算模型充分考虑了疏放水过程中钻孔内的层流和紊流水流特征。模型计算的1个主放水孔水量和2个观测孔水位历时变化和现场实际情况基本一致,模型可靠性好,且能解决倾斜钻孔在复合充水含水层中的水量分配问题。随着疏放水钻孔仰角的增大,单位长度的钻孔涌水量呈现先增加后减小的趋势,在仰角为60°时,钻孔单位涌水量最大,稳定水量为165 m^(3)/h,主要涌水层位为直罗组一段含水层,约占总涌水量的81%。此外,随着钻孔数量增加,单个钻场内钻孔总涌水量不断增加,单位长度的钻孔涌水量呈现逐步减小的趋势,钻孔数量增至5个后总涌水量基本稳定,钻孔稳定总涌水量约为440 m^(3)/h。在150 m钻场间距下600 m工作面范围中,60 d内,780 m定水头疏降时,钻孔总涌水量由1700 m^(3)/h降至170 m^(3)/h,降幅达90%;830和880 m定水头疏降下,钻孔总涌水量由1530,1350 m^(3)/h分别降至153,135 m^(3)/h,降幅均为90%。钻场内钻孔总涌水量受到周边钻场疏降干扰的影响,由两端向内侧影响逐步增大。780 m定水头疏降时,两端钻孔总涌水量约为309 m^(3)/h,最中间钻场钻孔总涌水量约为142 m^(3)/h。工作面内部水头分别降至780,830和880 m的时间分别为155,125和100 d。随着时间推移,不同降深范围逐步增大。随着疏放时间的延续,横剖面呈现以倾斜钻孔为中心的降落漏斗且范围逐步扩大,平面上则呈现以全部钻场范围为中心的降落漏斗且范围逐渐增大。 展开更多
关键词 水层-钻孔水量交换 疏放水钻孔 水量计算 仰角 疏水降压
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影响磷酸二铵产品水分含量因素分析 被引量:1
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作者 李沪萍 罗康碧 +1 位作者 周远清 谭艳霞 《化肥工业》 CAS 2007年第4期30-32,37,共4页
针对预中和反应槽-管式反应器混合工艺生产磷酸二铵产品时,产品水含量波动较大的生产现状进行了分析。造成产品水含量波动的原因主要有原料湿法磷酸的浓度、预中和槽料浆密度及干燥机进、出口风温等。如欲生产合格品和一等品,上述工艺... 针对预中和反应槽-管式反应器混合工艺生产磷酸二铵产品时,产品水含量波动较大的生产现状进行了分析。造成产品水含量波动的原因主要有原料湿法磷酸的浓度、预中和槽料浆密度及干燥机进、出口风温等。如欲生产合格品和一等品,上述工艺条件必须控制在一定的范围内,且波动幅度不能过大。 展开更多
关键词 磷酸二铵 产品 水量含 工艺条件
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钻孔涌水量、漏失量理论计算方法探讨 被引量:2
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作者 聂新明 顾成永 +1 位作者 刘广民 钱迪 《科学技术创新》 2018年第5期111-112,共2页
钻孔涌水量与漏失量在许多钻探工程中需要进行定量分析,传统方法多采用测量泥浆池冲洗液体积的变化来确定钻孔涌水量与漏失量。本文介绍理论计算方法是通过测定冲洗液在钻井中循环一周的时间来计算出钻孔涌水量、漏失量,并在某定向分支... 钻孔涌水量与漏失量在许多钻探工程中需要进行定量分析,传统方法多采用测量泥浆池冲洗液体积的变化来确定钻孔涌水量与漏失量。本文介绍理论计算方法是通过测定冲洗液在钻井中循环一周的时间来计算出钻孔涌水量、漏失量,并在某定向分支孔注浆工程中通过两种测定方法对比验证了理论计算方法的可行性和可靠性。 展开更多
关键词 水层区域注浆改造钻孔涌水量 漏失量 冲洗液循环时间
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Dry Matter Accumulation,Moisture Content in Maize Kernel and Their Influences on Mechanical Harvesting 被引量:17
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作者 阮龙 王俊 +4 位作者 陈义红 王世济 张玮 左晓龙 陈洪俭 《Agricultural Science & Technology》 CAS 2011年第12期1857-1860,共4页
[Objective] The aim of this study was to investigate the dry matter accumulation,moisture content in maize kernel and their influences on mechanical harvesting.[Methods] Using Zhengdan 958,Xianyu 335,Hongda 8 and Liyu... [Objective] The aim of this study was to investigate the dry matter accumulation,moisture content in maize kernel and their influences on mechanical harvesting.[Methods] Using Zhengdan 958,Xianyu 335,Hongda 8 and Liyu 16 as experimental materials,we preliminarily measured the dynamic changes of dry matter accumulation and moisture content with the days after pollination lasted,and investigated the effect of moisture content in kernels on mechanical harvesting of Zhengdan 958 and Liyu 16.[Results] During summer growing season,Zhengdan 958 and Liyu 16 became physiologically mature and suitable for harvesting at about 51 days after pollination,Xianyu 335 and Hongda 8 required 58 days to become physiologically mature and suitable for harvesting after pollination.At physiologically mature stage,the moisture contents in kernels of Zhengdan 958,Xianyu 335,Hongda 8 and Liyu 16 were respectively 33.74%,28.86%,32.05% and 35.24%,respectively.Adopting mechanical harvesting at physiologically mature stage,the kernel loss rate of Zhengdan 958 and Liyu 16 was consistent with the range of mechanical operation index(kernel loss rate of 0.84%≤2%),while the percentage of broken kernels did not accord with the range of mechanical operation index(kernel crashing rate of 10.12%≧1%).The results indicate that Zhengdan 958 and Liyu 16 are not suitable for mechanical harvesting using full feeding combine havester.[Conclusion] This study provided theoretical basis for improving the maize harvest index under delayed harvesting. 展开更多
关键词 Maize(Zea mays) Kernel weight Moisture content Physiological mature stage
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Spatial Variation and Sources of Atmospheric Sulfur Deposition in Nanchang 被引量:4
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作者 朱仁果 肖化云 +2 位作者 谢志英 吴亮红 吴代赦 《Agricultural Science & Technology》 CAS 2010年第3期162-165,共4页
[Objective] The paper aimed to discuss the relationship between sulfur contents of mosses and the concentration of SO2-4 and the source of Atmospheric sulfur in Nanchang.[Method] 29 moss samples (Bryohaplocladium mic... [Objective] The paper aimed to discuss the relationship between sulfur contents of mosses and the concentration of SO2-4 and the source of Atmospheric sulfur in Nanchang.[Method] 29 moss samples (Bryohaplocladium micriophyllum (Hedw.) R.Watanabe et Iwats) were collected from four sampling points,including North campus and Qianhu campus of Nanchang Power Station were determined.[Result] The results showed that sulfur contents of mosses tissues in North campus of Nanchang University (0.45±0.059%) were higher than Qianhu campus of Nanchang University (0.26±0.002%),which coincided with the changing law of the concentration of SO2-4.Sulphur isotope of mosses tissues was-0.64‰-9.71‰.Sulphur isotope of mosses tissues in Meling (4.02‰-9.71‰) was higher than Qianhu campus of Nanchang University (0.55‰-0.56‰) and power plant (-0.64‰-0.45‰).[Conclusion] Relationship between sulphur contents and sulphur isotopes of mosses tissues showed sulfur source of sulphur deposition in Nanchang city was mainly affected by 34S-enriched sulphur transported from northerly air masses and biogenic sulfur. 展开更多
关键词 Mosses tissues RAIN Sulphur contents Sulphur isotopes
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Effect of Nitrogen Application on Contents of Different Forms of Nitrogen in Rice Plants 被引量:9
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作者 莫润秀 江立庚 +6 位作者 郭立 胡均铭 刘开强 周佳民 梁天锋 曾可 丁成泉 《Agricultural Science & Technology》 CAS 2011年第10期1484-1489,共6页
[Objective]The paper was to study the effect of different nitrogen application levels and modes on contents of different forms of nitrogen in rice plants.[Method] Using Guichao 2 and Diejiazhan as test materials,with ... [Objective]The paper was to study the effect of different nitrogen application levels and modes on contents of different forms of nitrogen in rice plants.[Method] Using Guichao 2 and Diejiazhan as test materials,with total nitrogen,protein nitrogen,chlorophyll nitrogen,soluble protein nitrogen,Rubisco nitrogen,free amino acid nitrogen as indicators,the effect of nitrogen application on contents of different forms of nitrogen in rice plants were studied.[Result] The contents of total nitrogen,protein nitrogen,chlorophyll nitrogen,soluble protein nitrogen,Rubisco-N,free amino nitrogen of rice plant during heading and maturity stage increased with the increasing application amount of nitrogen,and their contents would be high under heavy application of spike fertilizer when the application amount of nitrogen was the same.However,application of nitrogen had different impact on different forms of nitrogen,which showed obvious impact on the contents of Rubisco-N and free amino nitrogen.The differences of Rubisco-N and free amino nitrogen content of two varieties during heading and maturity stage under different nitrogen application modes all reached significant or extremely significant level.Correlation analysis showed that total nitrogen content of rice plant had extremely significant correlation with protein nitrogen content during heading and maturity stage in both early and late seasons.[Conclusion] The study provided a theoretical basis for clarifying the regulatory role of nitrogen application on nitrogen absorption and utilization. 展开更多
关键词 Rice(Oryza sativa L.) Nitrogen content Nitrogen application Nitrogen forms
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Water content and modulus relationship of a compacted unsaturated soil 被引量:4
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作者 章定文 刘松玉 张涛 《Journal of Southeast University(English Edition)》 EI CAS 2012年第2期209-214,共6页
In order to assess the performance of the embankment soil under various climate conditions during the period of service, the modulus behaviour of an unsaturated compacted soil is evaluated using the constant water con... In order to assess the performance of the embankment soil under various climate conditions during the period of service, the modulus behaviour of an unsaturated compacted soil is evaluated using the constant water content triaxial test. Since the water content measurement method is simple and economical and it is used widely in engineering, the soil suction is replaced by the water content and the relationship between the water content and the modulus is developed. The compacted samples are prepared with different compacted water contents, and samples with a similar water content subjected to drying or wetting procedures prior to the triaxial test are also investigated. The effect of the water content and the confining pressure on the modulus is analyzed. The results show that the modulus decreases with the increase in the water content and a power function can be proposed to quantitatively describe the relationship between the modulus and the water content in the range of the measured water content. The modulus increases with the increase in the confining pressure of the compacted soil. However, the effect of the water content on the modulus is more pronounced than that of the confining pressure. This research can be referenced for the compacted embankment soil assessment in-service period. 展开更多
关键词 MODULUS water content unsaturated compacted soil
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Effects of Land Cover on Soil Temperature,Humidity and Moisture in Phoebe bournei Forest 被引量:9
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作者 吴际友 陈明皋 +5 位作者 董春英 黄小飞 黄明军 程勇 刘球 吴其军 《Agricultural Science & Technology》 CAS 2015年第12期2725-2729,共5页
Under the condition of high temperature, the effects of five cover patterns (clean tillage, film mulching, weed covering, branches and leaves covering and growing grass covering) on soil properties in young Phoebe b... Under the condition of high temperature, the effects of five cover patterns (clean tillage, film mulching, weed covering, branches and leaves covering and growing grass covering) on soil properties in young Phoebe boumei forest were in- vestigated. The results showed that the five cover patterns all showed significant ef- fects on soil properties in young Phoebe bournei forest under the condition of high temperature. Land cover increased land temperature in Phoebe boumei forest. Un- der the film mulching, the land temperature was increased most rapidly with the largest increment. However, weed covering, branches and leaves covering and growing grass covering decreased land temperature. Among them, growing grass covering showed the best cooling effect. The film mulching, weed covering, branch- es and leaves covering and growing grass covering all increased land humidity. The film mulching showed the best moisture-preserving effect in the early period, but in the late period, the humidity in the film mulching treatment group was lower than that in the clean tillage treatment group. Among the five mulching patterns, moisture loss in the film mulching treatment group was slowest and least, followed by those in the weed covering and branches and leaves covering treatment groups, and moisture loss in the growing grass covering treatment group was fastest and most. 展开更多
关键词 Soil management Land cover Land temperature Land humidity Soil moisture
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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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Regression Relationship between WI and FMC at Different Growth Periods of Sawtooth Oaks Leaf 被引量:2
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作者 费鲜芸 张志国 +2 位作者 卢霞 高祥伟 何润昭 《Agricultural Science & Technology》 CAS 2010年第7期49-52,共4页
[Objective] The aim was to study the regression relationship between water index (WI) and fuel moisture content (FMC) of different growth periods of sawtooth oaks leaf.[Method] Taking sawtooth oaks in Huaguo Mount... [Objective] The aim was to study the regression relationship between water index (WI) and fuel moisture content (FMC) of different growth periods of sawtooth oaks leaf.[Method] Taking sawtooth oaks in Huaguo Mountain,Lianyungang City as research object,the sensitivity of WI to leaf FMC was studied at leaf level,and statistical characteristics were analyzed.[Result] The WI of sawtooth oaks leaves was sensitive to the changes of FMC,and the line regression level between them was significant.A fitting curve between leaf FMC and WI was obtained.[Conclusion] The research provides reference for acquisition methods of vegetation water remote sensing within the range of study area. 展开更多
关键词 High spectral Fuel moisture index Water content Regression analysis Swatooth oaks leaf
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Effect of water content on corrosion inhibition behavior of self-assembled TDPA on aluminum alloy surface 被引量:1
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作者 屈钧娥 陈庚 +1 位作者 王海人 聂德键 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第10期3137-3144,共8页
Self assembled monolayers (SAMs) of 1-tetradecylphosphonic acids (TDPA, CH3(CH2)13P(O)(OH)2 ) were formed on the 2024 aluminum alloy surface in TDPA-containing ethanol-water solutions with different water co... Self assembled monolayers (SAMs) of 1-tetradecylphosphonic acids (TDPA, CH3(CH2)13P(O)(OH)2 ) were formed on the 2024 aluminum alloy surface in TDPA-containing ethanol-water solutions with different water content. The adsorption and corrosion protection properties of the SAMs for 2024 alloy in 0.1 mol/L H2SO4 solution were examined and characterized by potentiodynamic polarization, electrochemical impedance spectrum (EIS), Fourier transformed infrared spectroscopy (FTIR), Auger electron spectra (AES) and atomic force microscopy (AFM). FTIR and AES results show that the TDPA molecules were successfully adsorbed on the 2024 aluminum alloy surface, and the density of the SAMs increased with the increasing water content in the assembly solution. The results of electrochemical studies and corrosion morphologies observed by AFM show that a 4 h modification resulted in maximal inhibition efficiency, and the higher the water content in the assembly solution is, the better the inhibition performance of the SAMs can be achieved. The effect of water content in TDPA solutions on the performance of the SAMs is related to the hydration reaction of the metal surface. 展开更多
关键词 1-tetradecylphosphonic acid self-assembled monolayer aluminum alloys corrosion inhibition water content
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Research Progress of Evaluation Index of Soil Moisture 被引量:2
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作者 林坡 马友华 +4 位作者 江朝晖 王强 王静 黄浩 江宏 《Agricultural Science & Technology》 CAS 2016年第4期968-971,988,共5页
In modern agriculture, accurate and effective measurements of soil water content lays foundation for promotion on precision irrigation technology and improvement on water use efficiency. The research reviewed soil moi... In modern agriculture, accurate and effective measurements of soil water content lays foundation for promotion on precision irrigation technology and improvement on water use efficiency. The research reviewed soil moisture indices at home and abroad and classified the indices into two categories in order to make prediction on soil moisture and take measures. Specifically, single indices included precipitation index, soil moisture index, and crop drought index and overall indices included supply/demand water index of crops, overall water index, PDSI, crop water shortage index. Soil moisture index was analyzed in terms of advantages and disadvantages,as well as adaptability in agriculture, providing references for relieving and predicting adverse effects on agriculture and formulating scientific policies. 展开更多
关键词 Soil moisture index Soil moisture PROCESS EVALUATION
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Research on the Factors Affecting Nitrification Inhibition of Dicyandiamide(DCD) in Latosol 被引量:3
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作者 史云峰 赵牧秋 张丽莉 《Agricultural Science & Technology》 CAS 2011年第10期1505-1508,1516,共5页
[Objective] This research aimed at studying the effects of application amount of DCD and physics and chemistry characteristics of soil such as temperature,moisture content,organic matter content and pH on the inhibiti... [Objective] This research aimed at studying the effects of application amount of DCD and physics and chemistry characteristics of soil such as temperature,moisture content,organic matter content and pH on the inhibition of nitrification when applying nitrification inhibitor DCD in latosol.[Method] The experiment was carried out under aerobic incubated conditions.[Result] A significant delay period of nitrification was observed when the application amount of DCD was 10 mg/kg soil,and the inhibition can at least last for 56 d.When the cultural temperature had increased from 10 to 30 ℃,the duration of nitrification inhibition was shortened from 90 to 30 d.The nitrification inhibition of DCD was reduced with the increasing soil moisture content,organic matter content and soil pH,while the duration of nitrification inhibition was prolonged with the decreasing soil moisture content,organic matter content and soil pH.[Conclusion] Nitrification inhibition of DCD can be improved by increasing the application amount or reducing soil temperature,moisture content,organic matter content and pH. 展开更多
关键词 Nitrification inhibitor DICYANDIAMIDE LATOSOL TEMPERATURE Moisture content
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Effects of Different Plastic films Mulching on Soil Temperature and Moisture, the Growth and Yield of Sugarcane 被引量:3
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作者 许树宁 吴建明 +5 位作者 黄杏 谢金兰 罗亚伟 梁阗 黄家雍 李杨瑞 《Agricultural Science & Technology》 CAS 2015年第9期2073-2076,F0003,共5页
[Objective] The effects of different plastic films mulching on soil temperature and moisture, and growth and yield of sugarcane were discussed in order to provide references for using different plastic film in sugarca... [Objective] The effects of different plastic films mulching on soil temperature and moisture, and growth and yield of sugarcane were discussed in order to provide references for using different plastic film in sugarcane pro-duction. [Method]Four kinds of plastic films viz., normal colorless transparent plastic film, milky photodegradation weeding plastic film, black plastic film and gray-black plastic film were used in sugarcane cultivation by using no film mulching as the control. Soil temperature and moisture were measured during plastic film mulching period, and sugarcane agronomic traits such as emergence rate, tillering rate, plant hight, stalk diameter and effective stalk number were investigated during growth period, the cane yield and economic benefits were calculated during harvest period. [Result] The results showed that plastic film mulching could significantly increase soil temperature and moisture. Com-pared with the control, soil temperature was increased by 0.3-0.8 ℃ in three plastic films mulching treatment except for gray-black plastic film mulching. The soil moisture of all mulching treatments was 10.1%-17.4% higher than the control. Furthermore, the seedling emergence rate, tillering rate, effective stalk number and cane yield also could be improved using plastic film mulching,which were increased by 0.8%-9.9%, 20.6%-34.9%, 5190-10980 stalks/hm^2and6.4%-14.9% as compared to the control,while plant height and stalk diameter were found to be no significant effect by plastic film mulching. The results of benefit analysis indicated that, milky photodegradation weeding film mulching had the highest economic benefit, the second were normal colorless transparent plastic film mulching and black plastic film mulching, which were 5 987.2, 1 876.5 and 1 813.5 Yuan/hm^2 higher than the control. The gray-black film mulching treatment had poor benefit.[Conclusion] The milky photodegradation weeding plastic film could be vigorously extended in sugarcane production. Normal colorless transparent plastic film and black plastic film could be ex-tended gradually as a new kind of plastic film. The grayblack film should not be used for its higher cost and more thickness. 展开更多
关键词 Plastic film mulching Soil temperature Soil moisture SUGARCANE YIELD Economic benefit
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Variations in Composition and Water Use Efficiency of Plant Functional Groups Based on Their Water Ecological Groups in the Xilin River Basin 被引量:15
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作者 陈世苹 白永飞 韩兴国 《Acta Botanica Sinica》 CSCD 2003年第10期1251-1260,共10页
Major plant species in the Xilin River Basin were grouped into six plant functional groups (PFGs) based on their water ecological groups: xerophytes, mesoxerophytes, xeromesophytes, mesophytes, hygromesophytes and hyg... Major plant species in the Xilin River Basin were grouped into six plant functional groups (PFGs) based on their water ecological groups: xerophytes, mesoxerophytes, xeromesophytes, mesophytes, hygromesophytes and hygrophytes. We surveyed the composition, delta(13)C values and proline concentration of PFGs in eight different plant communities along a soil moisture gradient. Results show that: (1) PFGs occurred variously in eight steppe communities with different soil moisture status. In wetter habitats, hygromesophytes and hygrophytes were more abundant and accounted for the majority of aboveground biomass, whereas xerophytes and mesoxerophytes became more conspicuous in dryer habitats; (2) the numerical order of the mean delta(13)C values of PFGs is as follows: xerophytes (-26.38parts per thousand) = mesoxerophytes (-26.51parts per thousand) > xeromesophytes (-27.02parts per thousand) > mesophytes (-27.56parts per thousand) = hygromesophytes and hygrophytes (-27.80parts per thousand); (3) xerophytes maintained relative higher delta(13)C values and water use efficiency (WUE) in habitats of different water availability, whereas delta(13)C values of xeromesophytes were more sensitive to change in soil water availability; (4) From xerophytes to hygrophytes, their proline content markedly increased. Significantly positive correlations existed between proline and biomass or delta(13)C values of different water ecological groups. 展开更多
关键词 delta C-13 value water ecological groups soil moisture gradient water use efficiency PROLINE leaf water content (LWC)
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Preliminary Study on Spectra Diagnosis Model for Nitrogen Nutrition in Rice Leaf 被引量:4
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作者 李晓利 刘明博 +1 位作者 楼佳 唐延林 《Agricultural Science & Technology》 CAS 2011年第2期168-170,共3页
[Objective] The aim was to build spectral diagnosis model for nitrogen nutrition in rice leaf.[Method] Through determination of transmission,absorption spectra and nitrogen content on rice leaves of different rice var... [Objective] The aim was to build spectral diagnosis model for nitrogen nutrition in rice leaf.[Method] Through determination of transmission,absorption spectra and nitrogen content on rice leaves of different rice varieties(Xiangyou 109 and Shanyou 98),different growth periods and different nitrogen levels,we analyzed the correlation between leaf spectra and their nitrogen contents,and built prediction model of spectral index for nitrogen content in rice leaf.[Result] The detection precision of this model was above 80% that can be used on diagnosing of rice nitrogen nutrition.[Conclusion] The study provided evidence for monitoring nitrogen nutrition status of rice. 展开更多
关键词 RICE LEAF Nitrogen content Spectral index MODEL
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Physiological characteristics changes of Aesculus chinensis seeds during natural dehydration 被引量:8
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作者 喻方圆 杜艳 沈永宝 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期103-106,共4页
A study was conducted to determine the physiological characteristics changes of Aesculus chinensis seeds during natural dehydration in 2003. The results showed that A. chinensis seeds were recalcitrant with being high... A study was conducted to determine the physiological characteristics changes of Aesculus chinensis seeds during natural dehydration in 2003. The results showed that A. chinensis seeds were recalcitrant with being highly desiccation-sensitive. The seed moisture content of fresh fruits was higher than 60%. When the seeds were naturally dried for 30 days, their moisture content declined to 30.2% and their viability was completely lost. The seed germination percentage had a small increase at the beginning of desiccation and then decreased rapidly. The relative electrical conductivity of the A. chinensis seeds increased along with a decrease in seed moisture content. However, there was an abnormal increase in relative electrical conductivity when the seed moisture content was between 53.7% and 50.9%. Superoxide dismutase (SOD) activity decreased rapidly in the period of desiccation except for an abnormality when the seed moisture content was between 53.7% and 50.9%. Malondialdehyde (MDA) content increased slowly at the early stage of desiccation and then rose rapidly after the moisture content was below 50.9%. The soluble sugar content in seeds slowly increased with the increasing period of desiccation. The seed germination percentage was at the high level when seed moisture content was in range of 47%- 60%, which suggests that this was the optimum moisture content for maintaining A. chinensis seed viability. 展开更多
关键词 Aesculus chinensis SEEDS Air drying Physiological characteristics Seedmoisture content Seed germination percentage Superoxide dismutase (SOD) activity Malondialdehyde(MDA) content Seed electrical conductivity
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Effect of Deep Loosening on Soil Structure and Maize Root Activity 被引量:2
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作者 闫伟平 边少锋 +6 位作者 谭国波 赵洪祥 李海 张丽华 方向前 孟祥盟 孙宁 《Agricultural Science & Technology》 CAS 2016年第11期2539-2542,2545,共5页
[Objective] This study was conducted to explore the effects of deep loos- ening on soil structure and the activity of maize root system, to provide a theoreti- cal basis for the efficient and rational use of water res... [Objective] This study was conducted to explore the effects of deep loos- ening on soil structure and the activity of maize root system, to provide a theoreti- cal basis for the efficient and rational use of water resources. [Method] Three differ- ent loosening treatments for maize in ridges were performed in field trials as fol- lows: conventional ridge tillage, loosening the cm in spring (deep loosening in spring), and depth of 30 cm in autumn (deep loosening in soils between rows to a depth of 30 oosening the soils between rows to a autumn). Then the soil properties and the development of root system were measured to evaluate the effects of different loosening methods. [Result] Soil compactness was significantly reduced after deep loosening in spring, There were significant differences in soil compactness in 0-20 cm depth and soil bulk density in 0-40 cm depth between deep loosening in spring and deep loosening in autumn, deep loosening in spring and conventional ridge tillage. The soil water holding capacity was also significantly different between the two deep loosening treatments and conventional ridge tillage. Moreover, the root ac- tive absorption area of maize of deep loosening in spring was higher than that of conventionai ridge tillage. [Conclusion] Deep loosening can reduce soil compactness, bulk density, and improve soil water holding capacity, soil water content and the root activity of maize. Deep loosening in spring is better in soil improvement be- cause spring is closer to the growth period of crops than autumn. So, deep loosen- ing is conducive to the improvement of soil compactness and structure. 展开更多
关键词 Deep loosening Soil compactness Soil water content Root active ab- sorotion area
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Seasonal changes of soil respiration in Betula platyphylla forest in Changbai Mountain, China 被引量:2
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作者 刘颖 韩士杰 林鹿 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第4期367-371,I0007,共6页
A stdudy was conducted to determine the seasonal changes of soil respiration and the contribution of root respiration to soil respiration in Betula plaophylla forest in Changbai Mountain from May to September in 2004.... A stdudy was conducted to determine the seasonal changes of soil respiration and the contribution of root respiration to soil respiration in Betula plaophylla forest in Changbai Mountain from May to September in 2004. Results indicated that the total soil respiration, root-severed soil respiration and the root respiration followed a similar seasonal trend, with a high rate in summer due to wet and high temperature and a low rate in spring and autumn due to lower temperature. The mean rates of total soil respiration, root-severed soil respiration and root respiration were 4.44, 2.30 and 2.14 μmol.m^-2.s^-1, respectively during the growing season, and they were all exponentially correlated with temperature. Soil respiration rate had a linear correlation with soil volumetric moisture. The Q10 values for total soil respiration, root-severed soil respiration and root respiration were 2,82, 2.59 and 3. 16, respectively. The contribution rate of root respiration to the total soil respiration was between 29.3% and 58.7% during the growing season, indicating that root is a major component of soil respiration. The annual mean rates of total soil respiration, root-severed soil respiration and root respiration were 1.96, 1.08, and 0.87 μmol.m^-2.s^-1, or 741.73 408.71, and 329.24 g.m^-2.a^-1, respectively. Root respiration contributed 44.4% to the annual total soil respiration. The relationship proposed for soil respiration with soil lemperature was useful for understanding and predicting potential changes in Changbai Mountain B. platyphylla forest ecosystem in response to forest management and climate change. 展开更多
关键词 root respiration seasonal variations soil respiration soil temperature soil water content
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