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Study on Relative Soil and Water Conservation Benefits of Ridge Tillage in Different Terrain Conditions in the Black Soil Area of Northeast China
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作者 赵玉明 姜洪涛 王世界 《Agricultural Science & Technology》 CAS 2015年第10期2354-2360,共7页
Ridge tillage, which is a very common and important tillage measure in the black soil area of northeast China, has some soil and water conservation bene- fits, but has little attention. It is very important to explore... Ridge tillage, which is a very common and important tillage measure in the black soil area of northeast China, has some soil and water conservation bene- fits, but has little attention. It is very important to explore the spatial distribution of the ridge direction of the arable land and its soil and water conservation benefits in different terrain conditions in the black soil area. So Binxian County of Heilongjiang Province was selected as the study area, and 168 field investigation units were ex- tracted by stratified sampling method and investigated. According to equations of slope gradient factor and slope gradient in ridge direction, and based on the soft- ware of Arcmap, SPSS and Excel, the investigation data of soil and water loss in Binxian County were analyzed and counted, The results show that in plain, hilly and mountainous areas, the average ground slope gradients are 1.92°, 6.20° and 8.27° respectively, and the average slope gradients along ridge direction are 1.33°, 4.52°and 6.45° respectively, which account for about 70%, 73% and 78% of the average ground slope gradients in the same terrain condition; the relative quantities of soil erosion in the present ridge tillage condition account for about 55%, 69% and 67% respectively of that in down-slope ridge tillage conditions, so the present ridge tillage has obviously relative soil and water conservation benefits. Based on these results, the reasons of the present ridge tillage status were analyzed, and some reform measures were proposed. The results could not only help to comprehend the spatial distribution and soil and water conservation benefits of ridge tillage in the black soil area of Northeast China, but also provide scientific references for the layout of local soil and water conservation measures. 展开更多
关键词 The black soil area in northeast China ridge tillage ridge direction soil erosion Investigation of soil and water loss soil and water conservation benefits
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Impacts of long-term ridge culture on aggregate stability in purple paddy soil of Sichuan basin
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作者 唐晓红 《Journal of Chongqing University》 CAS 2010年第4期185-194,共10页
Ridge culture is a special conservation tillage method, but the long-term influence of this tillage system on soil aggregate-size stability in paddy fields is largely unknown in southwest of China. The paper is to eva... Ridge culture is a special conservation tillage method, but the long-term influence of this tillage system on soil aggregate-size stability in paddy fields is largely unknown in southwest of China. The paper is to evaluate soil aggregate stability and to determine the relationship between soil organic carbon (SOC) and soil aggregate stability. Soil samples at 0 cm-20 cm layer were adopted from a long-term (16 a) field experiment including conventional tillage: plain culture, summer rice crop and winter upland crop under drained conditions (PUR-r); and conservation tillage: ridge culture without tillage, summer rice and winter fallow with floodwater layer annually (NTR-f), winter upland crop under drained conditions (NTR-r), and wide ridge culture without tillage, summer rice crop and winter upland crop under conditions (NTRw-r), respectively. Different pretreatments, such as slaking in fast wetting, wetting and subsequent slaking, were applied to simulate the breakdown mechanisms of aggregates in paddy soil. The results show that soil particles contents were mainly consisted of silt (0.050 mm to 1.000 mm) in fraction of 42.9% to 51.2%, sand (0.050 mm to 0.001 mm) in fraction of 28.0% to 31.8%, and clay (<0.001 mm) in fraction of 17.9% to 25.4%. The amount of aggregate-size was greatly observed in fraction of 2.000 mm-6.720 mm under ridge culture in paddy soil (more than 50$) under slaking and wetting pretreatment. The proportion of soil macro-aggregates (>0.250 mm) in conservation tillage was greatly higher than that in conventional tillage under subsequent fast slaking treatment. Minimal differences of aggregate stability between slaking in fast wetting and wetting were observed, while significant differences were found between ridge culture and plain culture. The aggregate stability under slaking treatment ranked in the order of NTR-r>NTRw-r> NTR-f > PUR-r, while under wetting was NTRw-r > NTR-r > NTR-f >PUR-r. There was a positive correlation between the aggregate stability and SOC concentration under wetting, and a low correlation was observed under slaking pretreatment. Soil exposure with tillage and lack of rice/rape-seed stubble inputs caused declines in aggregation and organic carbon, both of which make soil susceptible to water erosion. Adoption of ridge culture with no-tillage integrated with crop rotation and stubble mulch significantly altered soil organic concentration. It was a valuable conservation practice for soil aggregation and soil organic carbon sequestration on paddy soil. 展开更多
关键词 ridge culture ROTATION aggregate stability organic carbon paddy soil
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Mulching broad ridges with a woven polypropylene fabric increases the growth and yield of young pear trees ‘Yuluxiang' in the North China Plain 被引量:1
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作者 Yang Wu Mingde Sun Songzhong Liu 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第3期414-424,共11页
Unlike traditional ridging, mulching broad ridges with a woven polypropylene fabric (WPF) can reduce soil evaporation during the drought season and avoid long saturation time in the root zone of pear trees during the ... Unlike traditional ridging, mulching broad ridges with a woven polypropylene fabric (WPF) can reduce soil evaporation during the drought season and avoid long saturation time in the root zone of pear trees during the rainy season. In this study, field experiments were conducted from 2017 to 2020 in a pear orchard in the North China Plain to investigate the effects of mulching broad ridges (0.3 m in height and 2 m in width) with WPF on soil temperature and moisture, nitrogen leaching, vegetative and reproductive growth of young pear trees(Pyrus bretschneideri Rehd.‘Yuluxiang’). The experiments involved two treatments, namely, control (traditional no-ridge planting without mulching) and mulching broad ridges with WPF (RM treatment). The results showed that the RM treatment increased soil moisture and temperature and decreased nitrogen leaching, resulting in vigorous growth of the young pear trees. Moreover, the RM treatment increased the tree trunk cross-sectional area and height of the young pear trees by 37%and 8%in 2020, respectively. The nitrate nitrogen content at the soil layer depth of 0-30 cm was significantly higher in the RM than that in control. Furthermore, the RM treatment significantly increased the fruit yield due to larger tree size. In addition, compared with control, significantly higher fruit soluble solid content of RM treatment was detected in 2020. High precipitation (423 mm) occurred during fruit enlargement stage in 2020, RM treatment decreased the rainfall infiltration in the ridge and the soil moisture in root region, resulting in the improvement of fruit quality, compared with control.Therefore, mulching broad ridges with WPF can be implemented to increase soil moisture during drought season, soil temperature, and nitrate nitrogen content, thereby improving the growth and fruit yield of young pear trees. Additionally, it can reduce soil moisture in the root zone during the rainy season and improve the fruit quality of the trees. Finally, it can reduce nitrate nitrogen leaching, thereby reducing environmental pollution. 展开更多
关键词 Pyrus bretschneideri Rehd Mulching broad ridges Trunk cross-sectional area Yield efficiency soil water content soil temperature
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Critical thresholds for stage division of water erosion process in different ridge systems in mollisol region of Northeast China
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作者 JIAO Jian QIN Wei +3 位作者 LI Kun-heng XU Hai-chao YIN Zhe HOU Shu-yan 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1540-1560,共21页
Extreme rainfall events on a slope under ridge tillage systems cause concentrated stream soil loss.To analyse the critical thresholds for different stages of water erosion process of ridge systems,simulated rainfall-e... Extreme rainfall events on a slope under ridge tillage systems cause concentrated stream soil loss.To analyse the critical thresholds for different stages of water erosion process of ridge systems,simulated rainfall-erosion experiments for the contour wide ridge(CWR),contour narrow ridge(CNR),longitudinal wide ridge(LWR),and longitudinal narrow ridge(LNR)were conducted under four rainfall intensities,with slope gradients of 3°and 5°.For the runoff event,the runoff depth order was LNR>LWR>CWR>CNR;the soil loss order was CNR>LNR>CWR>LWR.The product of slope factor(S)and rainfall erosivity(R)or runoff depth(D),can be adopted as critical thresholds for different stages of runoff and soil erosion process.For the longitudinal ridge systems,R values were provided for LWR and LNR and were the beginning of sheet flow,whereas the product of rainfall erosivity and slope factor(RS)values were provided for LWR and LNR as the beginning of the accelerated concentrated flow.For the contour ridge systems,R values were provided for CWR and CNR as critical thresholds for the beginning of overflow.The product of runoff depth and slope factor(DS)values were 9.98 and 7.73 mm for CWR and CNR,respectively,and were critical thresholds for the beginning of ridge failure;the DS values were 18.45 and 12.75 mm for CWR and CNR,respectively,and were critical thresholds for the beginning of the formation of ephemeral gully erosion.The critical thresholds can distinguish different stages of soil erosion process modelling. 展开更多
关键词 RUNOFF soil loss THRESHOLD ridge failure Artificial rainfall simulation
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Applying seepage modeling to improve sediment yield predictions in contour ridge systems
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作者 LIU Qianjin MA Liang ZHANG Hanyu 《Journal of Arid Land》 SCIE CSCD 2020年第4期676-689,共14页
Contour ridge systems may lead to seepage that could result in serious soil erosion. Modeling soil erosion under seepage conditions in a contour ridge system has been overlooked in most current soil erosion models. To... Contour ridge systems may lead to seepage that could result in serious soil erosion. Modeling soil erosion under seepage conditions in a contour ridge system has been overlooked in most current soil erosion models. To address the importance of seepage in soil erosion modeling, a total of 23 treatments with 3 factors, row grade, field slope and ridge height, in 5 gradients were arranged in an orthogonal rotatable central composite design. The second-order polynomial regression model for predicting the sediment yield was improved by using the measured or predicted seepage discharge as an input factor, which increased the coefficient of determination(R^2) from 0.743 to 0.915 or 0.893. The improved regression models combined with the measured seepage discharge had a lower P(0.007) compared to those combined with the predicted seepage discharge(P=0.016). With the measured seepage discharge incorporated, some significant(P<0.050) effects and interactions of influential factors on sediment yield were detected, including the row grade and its interactions with the field slope, ridge height and seepage discharge, the quadratic terms of the field slope and its interactions with the row grade and seepage discharge. In the regression model with the predicted seepage discharge as an influencing factor, only the interaction between row grade and seepage discharge significantly affected the sediment yield. The regression model incorporated with predicted seepage discharge may be expressed simply and can be used effectively when measured seepage discharge data are not available. 展开更多
关键词 soil erosion model contour ridge SEEPAGE geometry factors rainfall simulation
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一种快速分析土壤样品中^(90)Sr的方法 被引量:9
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作者 舒复君 杨金玲 +3 位作者 杨志红 丁有钱 梁小虎 张生栋 《核化学与放射化学》 CAS CSCD 北大核心 2013年第1期14-18,共5页
为了对核设施及周边环境的放射性污染水平进行有效监测,需要对大量土壤样品中的90 Sr进行分析。本工作以对锶有特效选择性的Sr.Spec树脂为主要分离纯化材料,结合浸取或全溶解预处理、草酸盐沉淀以及时间校准法与双标记法液闪测量,建立... 为了对核设施及周边环境的放射性污染水平进行有效监测,需要对大量土壤样品中的90 Sr进行分析。本工作以对锶有特效选择性的Sr.Spec树脂为主要分离纯化材料,结合浸取或全溶解预处理、草酸盐沉淀以及时间校准法与双标记法液闪测量,建立了快速分析土壤样品中90Sr的方法。全流程对Sr的化学回收率约为60%,分析时间小于6h,方法的最小可探测比活度为8Bq/kg。 展开更多
关键词 土壤 90sr sr·Spec树脂 液闪测量
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激光诱导击穿光谱技术分析土壤中的Cr和Sr 被引量:27
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作者 黄基松 陈巧玲 周卫东 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2009年第11期3126-3129,共4页
采用波长1064nm的调Q脉冲Nd∶YAG激光器和多通道小型光纤光栅光谱仪,建立了一套激光诱导击穿光谱分析装置。记录了系列土壤标准样品的激光诱导等离子体发射光谱,详细研究了重金属原子Cr和Sr的特征辐射谱线信号强度、标准偏差与数据采样... 采用波长1064nm的调Q脉冲Nd∶YAG激光器和多通道小型光纤光栅光谱仪,建立了一套激光诱导击穿光谱分析装置。记录了系列土壤标准样品的激光诱导等离子体发射光谱,详细研究了重金属原子Cr和Sr的特征辐射谱线信号强度、标准偏差与数据采样方式以及采样平均次数的关系,首次采用300个激光脉冲轰击样品表面同一点,并取其中最大光谱信号后的200次激光轰击等离子体发射光谱的平均值进行分析的取样平均方式,发现能较好地把对重金属Cr和Sr浓度分析测量的相对标准偏差(RSD)分别减小到9.02%和10.5%,并得到了定量分析Cr和Sr等金属的定标曲线,对Cr和Sr元素的检测灵敏度分别为25.3和15.2μg.g-1,优于目前国内外报道的结果。研究表明我们的采用的数据采集、分析定标方法对提高了LIBS技术在土壤中金属检测检测灵敏度和精密度具有很好的应用价值。 展开更多
关键词 激光诱导击穿光谱 土壤 CR sr 光谱分析
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东天山白鑫滩含铜镍矿镁铁-超镁铁岩体的岩石成因:年代学、岩石地球化学和Sr-Nd同位素证据 被引量:14
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作者 赵冰冰 邓宇峰 +5 位作者 周涛发 袁峰 张达玉 邓刚 李卫东 李跃 《岩石学报》 SCIE EI CAS CSCD 北大核心 2018年第9期2733-2753,共21页
自20世纪70年代以来,新疆东天山觉罗塔格构造带库姆塔格沙垅以东地区发现了大量的镁铁-超镁铁岩体和岩浆铜镍硫化物矿床,但是在沙垅以西地区没有大的找矿突破。白鑫滩含铜镍矿镁铁-超镁铁岩体为近几年在库姆塔格沙垅以西地区发现的岩浆... 自20世纪70年代以来,新疆东天山觉罗塔格构造带库姆塔格沙垅以东地区发现了大量的镁铁-超镁铁岩体和岩浆铜镍硫化物矿床,但是在沙垅以西地区没有大的找矿突破。白鑫滩含铜镍矿镁铁-超镁铁岩体为近几年在库姆塔格沙垅以西地区发现的岩浆铜镍硫化物矿床,研究工作薄弱,本文通过对白鑫滩岩体的岩石学、年代学、岩石地球化学和Sr-Nd同位素分析来解释其岩石成因。白鑫滩岩体不同岩相中矿物的粒径和含量的变化规律说明岩体为三期岩浆侵入作用形成,第一期为顶部的角闪辉长岩;第二期的橄榄辉长岩、斜长二辉橄榄岩和含长橄榄二辉岩,矿物种类相同,含量呈渐变关系;第三期为底部为的辉长岩,矿物粒径相对顶部的角闪辉长岩较小。白鑫滩岩体与黄山东、黄山西岩体具有相似的稀土元素和微量元素配分型式,大离子亲石元素(Rb、Ba、U、K)相对富集,而部分高场强元素(Nb、Ta、Ti)相对亏损,稀土元素呈轻稀土略微富集的右倾样式,均表现出岛弧火山岩的地球化学性质,εNd(t)值(2. 84~5. 05)和(^(87)Sr/^(86)Sr)(t)值(0. 704113~0. 705682)介于软流圈地幔与岩石圈地幔之间。但是与黄山东、黄山西岩体相比,白鑫滩岩体不相容元素含量更高,且εNd(t)值更低,(87Sr/86Sr)(t)值更高,还具有较高的La/Nb(2. 00~3. 33),较低的La/Ba(0. 02~0. 15),这些特征说明白鑫滩岩体的原始岩浆为岩石圈与软流圈物质相互作用的产物,且白鑫滩岩体的原始岩浆中软流圈物质相对于黄山东和黄山西岩体加入的比例更小。白鑫滩橄榄辉长岩年龄为287±3Ma,晚于该地区蛇绿岩(336~503Ma)、岛弧火山岩(320~322Ma)、岛弧花岗岩(316~328Ma)和含矿斑岩侵入体(326~334Ma)的年龄,与A型花岗岩和双峰式火山岩(284~294Ma)的年龄基本一致,而且白鑫滩岩体单斜辉石的化学成分与拉张裂谷环境的堆晶岩相似,因此推断白鑫滩岩体形成于后碰撞拉张环境。 展开更多
关键词 库姆塔格沙垅以西 白鑫滩镁铁-超镁铁岩体 sr-ND同位素 岩石圈地幔 后碰撞拉张 东天山
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SRSC垄宽和垄高对日光温室甜椒生长及产量的影响 被引量:5
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作者 傅国海 杨其长 +1 位作者 刘文科 闫文凯 《西北农业学报》 CAS CSCD 北大核心 2017年第9期1344-1348,共5页
为了探究不同宽度(基质或土壤体积)和高度的SRSC垄对甜椒生长及产量的影响,进而确定最优的SRSC栽培垄参数。以甜椒为试验材料,并以土壤栽培垄为对照(CK),分别设置10cm(W10)、35cm(W35)和40cm(W40/H15)不同宽度及0cm(H0)、10cm(H10)和15c... 为了探究不同宽度(基质或土壤体积)和高度的SRSC垄对甜椒生长及产量的影响,进而确定最优的SRSC栽培垄参数。以甜椒为试验材料,并以土壤栽培垄为对照(CK),分别设置10cm(W10)、35cm(W35)和40cm(W40/H15)不同宽度及0cm(H0)、10cm(H10)和15cm(W40/H15)不同高度的SRSC栽培垄,测定采收时甜椒的生长及产量指标。结果表明:不同宽度的SRSC垄中,CK与W35和W40/H15的甜椒的各项生长指标没有显著差异,而W10的甜椒的株高、茎粗和地上干鲜质量低于其他处理,生长最差,但其产量高于CK;W40/H15的甜椒产量最高,比CK高34.2%;不同高度的SRSC栽培垄中,H10甜椒的株高、茎粗及地上干鲜质量显著低于CK,生长最差,而H0和W40/H15甜椒的株高、茎粗、地上及地下干鲜质量没有显著差异,且二者的甜椒生长优于H10。H0的产量最低,而W40/H15的产量最高,比H0高60.4%,同时比CK高34.2%。综上,W40/H15对甜椒生长的影响相对较优,并且对其产量的提升效果最好,即SRSC垄宽为40cm,垄高为15cm时,生产性能最优。 展开更多
关键词 srSC垄 垄宽 垄高 甜椒 产量
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利用土壤Sr-Pb同位素差异性判别山药原产地研究 被引量:4
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作者 李向辉 陈云堂 +5 位作者 吕晓华 崔建勇 遆永周 杨保安 黄伦基 苑素华 《核农学报》 CAS CSCD 北大核心 2018年第3期515-522,共8页
为研究利用土壤Sr-Pb同位素差异性判别山药原产地的可行性,以山药表面附着土壤为对象,将其划分为5组,采用热电离质谱(TIMS)测定土壤和部分山药的Sr-Pb同位素比率,结合统计分析,进行山药产地判别研究。结果表明,采自于不同地域的I组和II... 为研究利用土壤Sr-Pb同位素差异性判别山药原产地的可行性,以山药表面附着土壤为对象,将其划分为5组,采用热电离质谱(TIMS)测定土壤和部分山药的Sr-Pb同位素比率,结合统计分析,进行山药产地判别研究。结果表明,采自于不同地域的I组和II组土壤样品Sr-Pb同位素差异不显著(P>0.05),表明其可能有共同的物质来源。两组样品采样地点均临近黄河,沙化严重,且均具有与黄河沉积物相似的同位素特征,I组、II组土壤样品都可能来源于黄河的沉积,应归为一类。不同产地土壤中Sr-Pb同位素差异显著(P<0.01),其中I组和II组土壤具有低的^(87)Sr/^(86)Sr比值(0.715195~0.715623);III组同时具有高的^(87)Sr/^(86)Sr比值(0.717906~0.718594)和高的^(206)Pb/^(204)Pb(18.643~18.765)、^(207)Pb/^(204)Pb比值(15.649~15.689);IV组同时具有中等的^(87)Sr/^(86)Sr比值(0.716004~0.716747)和中等的^(206)Pb/^(204)Pb(18.642~18.700)、^(207)Pb/^(204)Pb比值(15.634~15.650);V组具有较高的^(87)Sr/^(86)Sr比值(0.716081~0.718581)和最低的^(206)Pb/^(204)Pb(18.504~18.638)、^(207)Pb/^(204)Pb比值(15.572~15.614)。利用该差异可有效判别山药的原产地,产地判别准确率达到94.1%。本研究丰富了农产品原产地溯源判别体系。 展开更多
关键词 山药 sr-Pb 土壤 鉴别 产地
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稳定元素Sr在土柱中的迁移 被引量:8
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作者 杨月娥 李洋 +2 位作者 潘伟 王志明 倪世伟 《原子能科学技术》 EI CAS CSCD 北大核心 2006年第3期292-296,共5页
文章涉及稳定元素Sr在现场进行的水平土柱示踪实验和在实验室进行的垂直土柱模拟实验的实验方法和实验结果。实验结果表明:黄土对Sr有较强的吸附能力;实验室垂直土柱模拟实验的轴心纵向延迟系数略小于外侧纵向的数值;含水层水平土柱中S... 文章涉及稳定元素Sr在现场进行的水平土柱示踪实验和在实验室进行的垂直土柱模拟实验的实验方法和实验结果。实验结果表明:黄土对Sr有较强的吸附能力;实验室垂直土柱模拟实验的轴心纵向延迟系数略小于外侧纵向的数值;含水层水平土柱中Sr的延迟系数略小于实验室垂直土柱模拟实验的结果,这可能是由于土柱中的水流速度和土壤的密度不同而造成的。 展开更多
关键词 土柱 sr 实验场示踪实验 实验室模拟实验 延迟系数
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极低放废物填埋场土壤对U、Sr的吸附及影响 被引量:7
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作者 康厚军 张东 谢凌 《原子能科学技术》 EI CAS CSCD 北大核心 2009年第5期412-420,共9页
为了解U、Sr在极低放废物预选场址土壤中的吸附行为,分别以238U和90Sr溶液为示踪剂,用静态吸附法测定吸附分配系数,并研究pH、共存离子、胶体等条件的影响。研究结果表明:场址土壤对U、Sr的最大分配系数分别为11 300和723 mL/g;U... 为了解U、Sr在极低放废物预选场址土壤中的吸附行为,分别以238U和90Sr溶液为示踪剂,用静态吸附法测定吸附分配系数,并研究pH、共存离子、胶体等条件的影响。研究结果表明:场址土壤对U、Sr的最大分配系数分别为11 300和723 mL/g;U、Sr的吸附均符合Fruendlich等温吸附方程;当pH为4~8时,铀的吸附分配比最大,而锶的分配系数最小;Ca^2+和Mg^2+的引入均能降低土壤对U、Sr的吸附,且对Sr的影响大于对铀的影响;在CO3^2-和C2O4^2-浓度很低时,能显著降低U的吸附分配系数;而CO3^2-的存在能够增大其对Sr的吸附;Fe(OH)3胶体的存在使U、Sr的吸附分配系数显著降低;腐殖酸(HA)的存在使土壤对U的吸附减弱,但能够增大Sr在土壤中的吸附。 展开更多
关键词 极低放废物 土壤 吸附 U sr 腐殖酸
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~3H和^(90)Sr示踪剂在土壤包气层示踪实验中的应用 被引量:1
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作者 武清华 冀绍伟 +5 位作者 刘莲英 赵英杰 张华 王玉兵 李云峰 黄庆春 《同位素》 CAS 2001年第3期179-183,共5页
本工作测定了土壤包气层中 3 H和 90 Sr在天然条件和人工喷淋条件下的扩散系数 ,并研究了 3 H和 90 Sr示踪剂在黄土包气层中的迁移行为。结果表明 ,在华北地区黄土高原天然条件下 ,包气层中氚示踪剂以 0 .0 3cm/d速度迁移 ,纵向扩散系数... 本工作测定了土壤包气层中 3 H和 90 Sr在天然条件和人工喷淋条件下的扩散系数 ,并研究了 3 H和 90 Sr示踪剂在黄土包气层中的迁移行为。结果表明 ,在华北地区黄土高原天然条件下 ,包气层中氚示踪剂以 0 .0 3cm/d速度迁移 ,纵向扩散系数 Dx 为 0 .5 2 cm2 /d;在 2 m× 2 m实验坑中 ,以 5 mm/h喷淋强度每天喷淋 3h的条件下 ,氚示踪剂以 2 .2 7cm/d的速度向下迁移 ,纵向扩散系数 Dx 为 7.75cm2 /d。包气层中天然条件下 90 Sr基本没有迁移 ;人工喷淋条件下 ,90 Sr以 3.7× 10 -3 cm/d速度迁移 ,纵向扩散系数 Dx 为 0 .0 3m2 展开更多
关键词 ^3H ^90sr 示踪实验 土壤包气层 放射性废物 浅地层处置 安全分析 锶90 核素迁移
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土壤中^(90)Sr含量测定的改进方法 被引量:10
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作者 贾国纲 《辐射防护》 CAS CSCD 北大核心 1996年第3期224-232,共9页
本文介绍了土壤90Sr含量测定的改进方法。重点研究了210Bi对90Sr测定于扰的去除,采用Bi2S3沉淀和1mol/LHCl洗涤的方法,使对铋的去污因子由12.2提高到1050;分析50g土壤时,钇的化学回收率平均... 本文介绍了土壤90Sr含量测定的改进方法。重点研究了210Bi对90Sr测定于扰的去除,采用Bi2S3沉淀和1mol/LHCl洗涤的方法,使对铋的去污因子由12.2提高到1050;分析50g土壤时,钇的化学回收率平均为(72.9±17.3)%,检测限为0.27Bq/kg;将土壤样品分别用快速法和放置法进行测定,得到的90Sr含量的测定结果基本一致。 展开更多
关键词 土壤 锶90 含量测定
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^(90)Sr、^(137)Cs在某种包气带土壤中的迁移研究 被引量:9
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作者 杨勇 苑国琪 张东 《四川环境》 2004年第3期85-89,共5页
本文叙述了放射性废物中具有代表性的裂变核素90Sr,137Cs在某种包气带土壤中的迁移情况研究。使用小型土柱的氚水淋洗实验研究土壤水力学性质,最后进行大型土柱实验研究核素在该包气带土壤中的迁移,并对实验情况进行了数学模拟。用该土... 本文叙述了放射性废物中具有代表性的裂变核素90Sr,137Cs在某种包气带土壤中的迁移情况研究。使用小型土柱的氚水淋洗实验研究土壤水力学性质,最后进行大型土柱实验研究核素在该包气带土壤中的迁移,并对实验情况进行了数学模拟。用该土壤原状土进行小型土柱的氚水淋洗试验,测得了土壤的水力弥散度为0 32cm,土壤有效孔隙度为0 35。经过290天的大型柱迁移试验表明,土壤对90Sr的阻滞系数为220 4,在模拟实际降雨量的情况下,90Sr的平均迁移速度为0 63cm/y,137Cs在大型柱试验中没有明显迁移。数值模拟90Sr、137Cs迁移,得出经过上述大型柱试验相同的条件下,90Sr、137Cs迁移的峰位置基本和大型柱试验结果相同。 展开更多
关键词 核素迁移 包气带土壤 ^90sr、^137Cs
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发烟硝酸-萃取色层法测定土壤中的^(90)Sr 被引量:3
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作者 刘扬 顾明杰 《湿法冶金》 CAS 2001年第1期44-46,共3页
以发烟硝酸萃取色层法测定土壤中^(90)Sr简单 ,快速 ,结果精密度较好。给出了分析步骤。
关键词 发烟硝酸 萃取色层 土壤
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土壤样品中^(90)Sr测定的前处理 被引量:1
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作者 玄光善 金文昌 +1 位作者 许大成 李兴洛 《湿法冶金》 CAS 2005年第1期48-51,共4页
用硝酸沉淀法处理环境土壤样品时,经多次沉淀和溶解过程,使90 Sr有部分损失。跟踪90 Sr 的损失过程,可从中找出提高90Sr浸出率的方法。在生成碳酸盐沉淀后,用离心法在 3 000 r/min条件下,分离出含有腐殖酸的上层清液。土壤前处理过程中,... 用硝酸沉淀法处理环境土壤样品时,经多次沉淀和溶解过程,使90 Sr有部分损失。跟踪90 Sr 的损失过程,可从中找出提高90Sr浸出率的方法。在生成碳酸盐沉淀后,用离心法在 3 000 r/min条件下,分离出含有腐殖酸的上层清液。土壤前处理过程中,90 Sr浸出率下降最大的是在草酸盐沉淀生成过程中,特别是在 pH为4.0、生成褐色沉淀时,下降得更为明显。加入过量的草酸使生成白色沉淀并对上层澄清液进行再沉淀,可将90Sr回收率提高到80%~90%。 展开更多
关键词 沉淀 土壤样品 环境土壤 腐殖酸 前处理 离心法 回收率 硝酸 草酸 碳酸盐
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ICP-AES法测定土壤和地下水中Sr、Nd、Ce 被引量:2
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作者 焦志兰 孟莉萍 《辐射防护通讯》 2005年第1期32-35,共4页
采用酸法消解样品,分析了用ICPAES法测定环境土壤和地下水中Sr、Nd、Ce的工作条件。方法对Sr、Nd、Ce的检出限分别为0.001、0.04和0.04μg/mL,相对标准偏差<5%。用国家标准物质GSS1和GSS8的测定结果表明,测定值与推荐值一致,能够满... 采用酸法消解样品,分析了用ICPAES法测定环境土壤和地下水中Sr、Nd、Ce的工作条件。方法对Sr、Nd、Ce的检出限分别为0.001、0.04和0.04μg/mL,相对标准偏差<5%。用国家标准物质GSS1和GSS8的测定结果表明,测定值与推荐值一致,能够满足环境土壤和水中Sr、Nd、Ce的测定要求。 展开更多
关键词 电感耦合等离子体发射光谱法 土壤地下水 sr ND CE
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萃取色层法分离测定放射性污染土样品中^(238-240)Pu、^(241)Am和^(90)Sr 被引量:1
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作者 靳小军 李绪平 《广州化工》 CAS 2021年第22期69-72,共4页
建立了萃取色层法测定放射性污染土样品中^(238-240)Pu、^(241)Am和^(90)Sr的方法。1.0g放射性污染土样品经高压消解,采用串联的TEVA、TRU和SR萃取色层柱分离富集溶解液中^(238-240)Pu、^(241)Am和^(90)Sr,经不同的淋洗液解析后,α能谱... 建立了萃取色层法测定放射性污染土样品中^(238-240)Pu、^(241)Am和^(90)Sr的方法。1.0g放射性污染土样品经高压消解,采用串联的TEVA、TRU和SR萃取色层柱分离富集溶解液中^(238-240)Pu、^(241)Am和^(90)Sr,经不同的淋洗液解析后,α能谱法测定^(238-240)Pu和^(241)Am,切伦科夫计数法测定^(90)Sr。结果表明:方法对^(238-240)Pu加标回收率在81.4%~96.5%之间,精密度为13.1%;对^(241)Am加标回收率在88.0%~94.0%之间,精密度为12.9%;对^(90)Sr加标回收率在89.0%~96.1%之间,精密度为8.4%。 展开更多
关键词 萃取色层法 放射性污染土 ^(238-240)Pu 、^(241)Am ^(90)sr
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朝阳凤凰山古土壤剖面Rb、Sr的分布及Rb/Sr比值对土壤风化成壤作用的指示意义
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作者 郭月 刘素花 王圆方 《农业科技与装备》 2010年第4期9-11,共3页
通过对辽宁省朝阳市凤凰山古土壤剖面中各地层土壤Rb、Sr含量的测定,分析Rb和Sr的分布特征并通过Rb/Sr比值判断土壤的风化成壤作用强弱。结果表明,在整个剖面中,Sr含量变化幅度明显大于Rb的变化幅度;Rb/Sr比值的变化与Sr含量变化呈显著... 通过对辽宁省朝阳市凤凰山古土壤剖面中各地层土壤Rb、Sr含量的测定,分析Rb和Sr的分布特征并通过Rb/Sr比值判断土壤的风化成壤作用强弱。结果表明,在整个剖面中,Sr含量变化幅度明显大于Rb的变化幅度;Rb/Sr比值的变化与Sr含量变化呈显著的负相关系,且黄土层的Rb/Sr比值明显低于古土壤层;Rb/Sr比值可指示土壤风化成壤作用强弱,在朝阳凤凰山古土壤剖面中,S4层经受的风化成壤作用最强,而L1层经受的风化成壤作用最弱。 展开更多
关键词 RB sr RB/sr 古土壤 成壤作用 朝阳
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