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模拟降雨条件下泥沙荷载随坡面侵蚀过程的变化(英文)
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作者 孙莉英 方海燕 +4 位作者 蔡强国 杨希华 和继军 周俊良 王训明 《地理学报:英文版》 SCIE CSCD 2019年第6期1001-1020,共20页
It is of great significance to quantify sediment load changing with erosion processes for improving the precision of soil loss prediction. Indoor rainfall experiments were conducted in 2 rainfall intensities(90 mm... It is of great significance to quantify sediment load changing with erosion processes for improving the precision of soil loss prediction. Indoor rainfall experiments were conducted in 2 rainfall intensities(90 mm·h-1 and 120 mm·h-1), four slope gradients(17.60%, 26.80%, 36.40%, 46.60%) and 2 slope lengths(5 m, 10 m). Erosion processes are divided into five stages. Results show that sediment yield is mainly sourced from rill erosion, contributing from 54.60% to 95.70% and the duration of which is extended by slope gradients. Sediment load and sediment concentration are significantly different along erosion stages, with the highest values in rill development stage(SIV). Surface flow velocities(interrill and rill) demonstrate less significant differences along erosion stages. Rainfall intensity increases sediment load in all stages, with up to 12.0 times higher when changing from 90 to 120 mm·h-1. There is an increasing trend for sediment load and sediment concentration with the rising slope gradient, however, fluctuations existed with the lowest values on 26.80% and 36.40%, respectively, among different treatments. The slope gradient effects are enhanced by rainfall intensity and slope length. Results from this study are important for validating and improving hillslope erosion modelling at each erosion stage. 展开更多
关键词 RAINFALL simulation EROSION EXPERIMENTS RILL EROSION interrill EROSION sediment load
不同冲蚀速度与角度下的防砂管冲蚀规律 预览
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作者 吕宁博 翟晓鹏 +2 位作者 张春阳 冯云爽 刘思雨 《化工设计通讯》 CAS 2019年第3期129-130,共2页
高速含砂流体的冲蚀作用造成的防砂管基管破坏是防砂失效的重要原因之一。利用旋转MSH冲蚀仪模拟地层环境,以含砂流体为实验介质,从筛管基管上裁剪出50mm×20mm×2mm的样块作为实验试样,研究其在固液两相流体中不同冲蚀速度与... 高速含砂流体的冲蚀作用造成的防砂管基管破坏是防砂失效的重要原因之一。利用旋转MSH冲蚀仪模拟地层环境,以含砂流体为实验介质,从筛管基管上裁剪出50mm×20mm×2mm的样块作为实验试样,研究其在固液两相流体中不同冲蚀速度与角度下的冲蚀规律。实验发现:相同实验条件下,冲蚀磨损量与冲蚀角度成反比、与冲蚀速度成正比且成指数增长。因此可以调整设计筛管结构以增大含砂流体与筛管基管的冲蚀角度,同时在油田开发前期降低生产速度,减小冲蚀磨损,后期增大生产速度,保证总体产量。 展开更多
关键词 防砂 筛管 冲蚀 固液两相流体 冲蚀角度 冲蚀速度
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An experimental study on the influences of water erosion on wind erosion in arid and semi-arid regions
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作者 YANG Huimin ZOU Xueyong +1 位作者 WANG Jing’ai SHI Peijun 《干旱区科学:英文版》 SCIE CSCD 2019年第2期208-216,共9页
Complex erosion by wind and water causes serious harm in arid and semi-arid regions. The interaction mechanisms between water erosion and wind erosion is the key to further our understanding of the complex erosion. Th... Complex erosion by wind and water causes serious harm in arid and semi-arid regions. The interaction mechanisms between water erosion and wind erosion is the key to further our understanding of the complex erosion. Therefore, in-depth understandings of the influences of water erosion on wind erosion is needed. This research used a wind tunnel and two rainfall simulators to investigate the influences of water erosion on succeeding wind erosion. The wind erosion measurements before and after water erosion were run on semi-fixed aeolian sandy soil configured with three slopes(5°, 10° and 15°), six wind speeds(0, 9, 11, 13, 15 and 20 m/s), and five rainfall intensities(0, 30, 45, 60 and 75 mm/h). Results showed that water erosion generally restrained the succeeding wind erosion. At a same slope, the restraining effects decreased as rainfall intensity increased, which decreased from 70.63% to 50.20% with rainfall intensity increased from 30 to 75 mm/h. Rills shaped by water erosion could weaken the restraining effects at wind speed exceeding 15 m/s mainly by cutting through the fine grain layer, exposing the sand layer prone to wind erosion to airflow. In addition, the restraining effects varied greatly among different soil types. The restraining effects of rainfall on the succeeding wind erosion depend on the formation of a coarsening layer with a crust and a compact fine grain layer after rainfall. The findings can deepen the understanding of the complex erosion and provide scientific basis for regional soil and water conservation in arid and semi-arid regions. 展开更多
关键词 WIND EROSION WATER EROSION SANDY soil particle size surface ROUGHNESS wind-water EROSION agriculturalpastoral ECOTONE
基于CSLE模型和抽样单元法的县域土壤侵蚀估算方法对比 预览
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作者 李子轩 赵辉 +3 位作者 邹海天 李依珊 刘雨鑫 李骜 《农业工程学报》 EI CAS CSCD 北大核心 2019年第14期141-148,共8页
为提高县域尺度地块(栅格)土壤侵蚀模数估算的准确性,以河北省怀来县为例,基于CSLE模型,分别采用全域覆盖计算和4%密度抽样单元推算方法对全县土壤侵蚀进行计算和对比分析。结果表明:全域覆盖计算比4%抽样单元推算水土流失面积大59.0km... 为提高县域尺度地块(栅格)土壤侵蚀模数估算的准确性,以河北省怀来县为例,基于CSLE模型,分别采用全域覆盖计算和4%密度抽样单元推算方法对全县土壤侵蚀进行计算和对比分析。结果表明:全域覆盖计算比4%抽样单元推算水土流失面积大59.0km^2,相对差异达12.94%。全域覆盖计算可实现空间全覆盖,更准确地反映县域水土流失空间分布特点,适用于中、小尺度土壤侵蚀定量计算,但需要较高精度和全面的数据源保证;抽样单元推算适用于流域、区域等大尺度土壤侵蚀估算,但结果受抽样方法、抽样密度、外推或插值方法等因素影响较大。应进一步加强遥感解译准确性、侵蚀因子精度等对CSLE全域覆盖计算结果影响的研究,完善模型参数数据库,率定因子值,实现参数本地化。 展开更多
关键词 土壤 侵蚀 估算 CSLE模型 全域覆盖计算 抽样单元推算 土壤侵蚀评估 县域
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Partition-coordinated control of soil and water loss for chestnut forests in the Yanshan Mountain Region,China 预览
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作者 Xinhui Ding Guangquan Liu +2 位作者 Xiaoying Liu Yongsheng Xie Zhichun Yue 《国际泥沙研究:英文版》 SCIE 2019年第1期58-64,共7页
Soil erosion from chestnut forests is one of the most important factors causing land degradation in the Yanshan Mountain Region.A 2-year field study was done to compare the effects on erosion of a control plot(CP),a r... Soil erosion from chestnut forests is one of the most important factors causing land degradation in the Yanshan Mountain Region.A 2-year field study was done to compare the effects on erosion of a control plot(CP),a repaired and maintained horizontal ditch built with an engineering baffle every 6m(MP 1),and a repaired and maintained horizontal ditch built with an engineering baffle every 8m(MP 2).The results showed that the slope runoff of chestnut forests was influenced by rainfall characteristic factors.No single rainfall characteristic factor showed dominance for hill slope runoff.The runoff reduction effect of the partition-coordinated erosion control measures(MP 1 and MP 2)was substantial for chestnut forests under high rainfall intensity conditions.However,the runoff reduction efficiency was higher under the conditions of heavy rainfall and low average rainfall intensity than for storms with higher intensity and lower total rainfall.The reduction effect of the partition-coordinated erosion control measures on the runoff and sediment yield of chestnut forest slopes was MP 2 4 MP 1 4 CP.The runoff reduction rate and erosion reduction rate of MP 2 reached 61.70%and 97.41%,respectively,and that for MP 1 was 54.15%and 85.31%,respectively.Therefore,after a comprehensive comparison,MP 2 was determined to be more effective for soil erosion control for a sloping chestnut forest. 展开更多
关键词 CHESTNUT forest Soil and water loss EROSION control RUNOFF REDUCTION RATE EROSION REDUCTION RATE
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Use of incipient motion data for backward erosion piping models 预览
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作者 Vera M. van Beek Bryant A. Robbins +2 位作者 Gijs J.C.M. Hoffmans Adam Bezuijen Leo C. van Rijn 《国际泥沙研究:英文版》 SCIE 2019年第5期401-408,共8页
Backward erosion piping involves the gradual removal of granular material under the action of water flow from the foundation of a dam or levee, whereby shallow pipes are formed that grow in the direction opposite to t... Backward erosion piping involves the gradual removal of granular material under the action of water flow from the foundation of a dam or levee, whereby shallow pipes are formed that grow in the direction opposite to the flow. This pipe-forming process can ultimately lead to failure of a water-retaining structure and is considered one of the most important failure mechanisms for dikes and levees in the Netherlands and the United States. Modeling of this mechanism requires the assessment of hydraulic conditions in the pipe, which are controlled by the particle equilibrium at the pipe wall. Since the pipe's dimensions are controlled by the inflow to the pipe from the porous medium, the flow through the pipe is thought to be laminar for fine- to medium-grained sands. The literature provides data for incipient motion in laminar flow, which is reviewed here and complemented with data from backward erosion experiments. The experiments illustrate the applicability of the laminar incipient motion data to determine the erosion pipe dimensions and corresponding pipe hydraulics for fine- to medium-grained sands, for the purpose of backward erosion piping modeling. 展开更多
关键词 Internal EROSION BACKWARD EROSION PIPING CYLINDRICAL test Incipient motion DIKES LEVEES
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陕北子洲“7·26”暴雨后坡耕地细沟侵蚀及其影响因素分析 预览
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作者 王颢霖 焦菊英 +4 位作者 唐柄哲 陈一先 白雷超 王楠 张意奉 《农业工程学报》 EI CAS CSCD 北大核心 2019年第11期122-130,共9页
细沟侵蚀研究多数基于模拟降雨条件,野外自然状态下的研究相对较少,而极端暴雨条件下的细沟侵蚀研究更为鲜见。该文对陕西子洲2017年"7·26"特大暴雨条件下坡耕地发育的细沟开展调查,研究坡位(距分水岭距离)、坡度和坡形... 细沟侵蚀研究多数基于模拟降雨条件,野外自然状态下的研究相对较少,而极端暴雨条件下的细沟侵蚀研究更为鲜见。该文对陕西子洲2017年"7·26"特大暴雨条件下坡耕地发育的细沟开展调查,研究坡位(距分水岭距离)、坡度和坡形对坡耕地细沟侵蚀特征的影响。结果表明:通过对35个样方的143条细沟统计,细沟宽度和细沟深度分别为0.5~60 cm和0.5~35 cm;细沟侵蚀强度、细沟密度和细沟割裂度分别为2 289~110 976 t/km^2、0.3~3.95 m/m^2和0.002~0.441。随距分水岭距离(17~58 m)的增加,细沟先快速发育,坡面破碎程度加剧,距分水岭58m后,细沟发育减慢,坡面破碎程度减弱。坡度在不同的坡位对细沟侵蚀的影响程度不同:随坡度增大,上坡位(距分水岭20~40m),细沟侵蚀强度陡升,坡面破碎程度加剧;下坡位(距分水岭60~80m),细沟侵蚀强度增加较缓慢,坡面破碎程度减弱。凸形坡中部为细沟侵蚀(10 292t/km^2)最为严重区域,下部(8 141t/km^2)次之,上部无细沟发生;细沟密度、细沟割裂度和细沟平均宽度先增大后减小,细沟平均深度递增。浅沟地形细沟侵蚀随距分水岭距离的增加而增加,但退耕地的存在减缓了细沟侵蚀发育程度。直形坡因坡度最大其细沟侵蚀最严重,细沟形态同其他坡形基本相同,但最大沟宽和沟深均大于其他坡形。研究结果可为黄土高原坡耕地的水土流失防治提供参考。 展开更多
关键词 土壤 侵蚀 暴雨 细沟侵蚀 坡耕地 坡形 坡度 距分水岭距离
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鞍钢高炉炉缸异常侵蚀的原因及对策探析
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作者 姜喆 车玉满 +2 位作者 郭天永 谢明辉 李建军 《炼铁》 北大核心 2019年第2期5-8,共4页
对鞍钢近年来高炉炉缸破损调查情况进行了阐述。从炉缸侵蚀的状况来看,铁水环流、炭砖应力破坏、化学氧化侵蚀和炭素胶泥的质量不合格是鞍钢高炉炉缸异常侵蚀的主要原因。另外,基于对炉衬侵蚀原因和特征的分析.提出了应从设计、制造与... 对鞍钢近年来高炉炉缸破损调查情况进行了阐述。从炉缸侵蚀的状况来看,铁水环流、炭砖应力破坏、化学氧化侵蚀和炭素胶泥的质量不合格是鞍钢高炉炉缸异常侵蚀的主要原因。另外,基于对炉衬侵蚀原因和特征的分析.提出了应从设计、制造与施工、烘炉、开炉和日常生产操作等方面采取有措施,以延长高炉炉缸使用寿命。 展开更多
关键词 高炉 炉缸 侵蚀 铁水环流 化学侵蚀
冲蚀磨损机理及抗冲蚀涂层研究进展 预览
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作者 李力 魏天酬 +1 位作者 刘明维 周超 《重庆交通大学学报:自然科学版》 CAS CSCD 北大核心 2019年第8期70-74,91,共6页
冲蚀磨损现象广泛存在于工程结构中,是许多行业结构破坏与装备失效的主要原因之一,每年造成能源与材料上的巨大经济损失。综合评述了微切削理论、变形磨损理论、磨损脱层理论、二次冲蚀理论和锻造挤压理论等塑性材料冲蚀理论以及弹性压... 冲蚀磨损现象广泛存在于工程结构中,是许多行业结构破坏与装备失效的主要原因之一,每年造成能源与材料上的巨大经济损失。综合评述了微切削理论、变形磨损理论、磨损脱层理论、二次冲蚀理论和锻造挤压理论等塑性材料冲蚀理论以及弹性压痕理论等脆性材料冲蚀理论,并且针对现有主要冲蚀防护方法中的涂层保护法抗冲蚀原理作出介绍,最后提出了目前冲蚀磨损相关研究中的主要问题和未来的研究重点。 展开更多
关键词 航道工程 冲蚀磨损 冲蚀理论 涂层
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不同沙埋程度下带状沙障的防风固沙效果研究 预览
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作者 袁立敏 黄海广 +1 位作者 闫德仁 胡小龙 《农业工程学报》 EI CAS CSCD 北大核心 2019年第16期172-179,共8页
沙障在防护过程中,易发生沙障沙埋现象。为了对比分析不同沙埋程度下沙障的防风固沙效果差异,该文通过风洞模拟和野外试验相结合的方法,研究了沙袋沙障在裸露、浅埋、深埋3种状态下,防护区近地层风流场、输沙通量等风沙运动规律,并以未... 沙障在防护过程中,易发生沙障沙埋现象。为了对比分析不同沙埋程度下沙障的防风固沙效果差异,该文通过风洞模拟和野外试验相结合的方法,研究了沙袋沙障在裸露、浅埋、深埋3种状态下,防护区近地层风流场、输沙通量等风沙运动规律,并以未设置沙障的流沙区作为对照,明确了沙埋过程中沙障的防风固沙效果变化规律。结果表明,沙障在经历裸露至深埋过程中:1)对过境气流的防护距离、防护高度逐渐减小,近地层风速廓线变化趋势与对照相同,并逐渐服从对数函数;2)沙障防护区输沙分布高度显著降低(P<0.01),输沙分布高度由42 cm(裸露)降低至34 cm(浅埋),最终降至28 cm(深埋),而对照的输沙分布高度为24 cm;3)近地层输沙率分布曲线逐渐服从对数函数,0~50 cm高度范围输沙量也呈现递增趋势;4)3种埋设深度野外试验说明,经过两个风季后,裸露、浅埋、深埋的沙袋沙障防护区土壤风蚀呈现降低趋势,风蚀深度分别比对照降低了18.53%、72.97%、80.40%。研究可以为沙障高度优化及应用技术提升提供理论依据。 展开更多
关键词 土壤 侵蚀 沙障 风蚀 风速流场 风速廓线 输沙量
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基于三维重建技术的坡面细沟侵蚀演变过程研究 预览
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作者 吴淑芳 刘勃洋 +4 位作者 雷琪 孙立全 郭慧莉 冯喆 钱阔 《农业工程学报》 EI CAS CSCD 北大核心 2019年第9期114-120,共7页
作为黄土高原地区沟头溯源侵蚀和水流汇集发源地的梁峁坡面,在强降雨下其产流产沙对沟缘线以下坡面及沟道侵蚀有着重大影响。该研究根据野外实地考查构建5°~35°变坡段实体模型,进行6场间歇性人工模拟降雨试验,并借助基于三维... 作为黄土高原地区沟头溯源侵蚀和水流汇集发源地的梁峁坡面,在强降雨下其产流产沙对沟缘线以下坡面及沟道侵蚀有着重大影响。该研究根据野外实地考查构建5°~35°变坡段实体模型,进行6场间歇性人工模拟降雨试验,并借助基于三维重建技术的PhotoScan软件获取坡面DEM,将其侵蚀演化过程进行图形化、数字化,定性定量揭示其侵蚀形态演变特征。研究表明:1)梁峁坡面细沟侵蚀历经4个阶段:面蚀阶段,即产生一系列呈串珠状分布的侵蚀跌坑,宽度5~9cm,深度1~4cm;细沟形成阶段,由面蚀所产生的微小跌坑在径流作用下长、宽、深均不断增大,最大分别达到266、7.6、13.8cm;细沟网形成阶段,细沟出现分叉及联通,有明显流路;小切沟形成阶段,伴随沟壁崩塌、沟壁加宽和沟底下切,最大沟长及最大沟深较细沟形成时增大3倍以上。2)对比次降雨过程基于三维建模所计算侵蚀量与实测侵蚀量,第1场降雨试验因地表疏松颗粒较多导致实测侵蚀量比建模计算侵蚀量大而引起较大偏差(20.82%),其他场次偏差均在10%左右或以下,总体来说,该技术可以较好地应用于侵蚀发育过程的研究。该研究实现侵蚀演变关键过程图形化、数字化,有助于人们定性、定量了解和认识梁峁坡面侵蚀过程,且对于创新侵蚀过程研究方法亦具有实践指导价值。 展开更多
关键词 土壤 侵蚀 照片重建 人工模拟降雨试验 细沟侵蚀 演化过程
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墨西哥海岸线演变
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作者 VALDERRAMA-LANDEROS Luis H. MARTELL-DUBOIS Raúl +3 位作者 RESSL Rainer SILVA-CASARíN Rodolfo CRUZ-RAMíREZ Cesia J. MUNOZ-PEREZ Juan J. 《地理学报:英文版》 SCIE CSCD 2019年第10期1637-1654,共18页
The goal of our work was to locate and quantify changes that occurred in 66% of the Mexican coastline, based on four land cover maps generated by the Mexican Mangrove Monitoring System(SMMM) of the National Commission... The goal of our work was to locate and quantify changes that occurred in 66% of the Mexican coastline, based on four land cover maps generated by the Mexican Mangrove Monitoring System(SMMM) of the National Commission for the Knowledge and Use of Biodiversity(CONABIO) for the years 1970/81, 2005, 2010, and 2015. Our results showed overall dominance of erosion over accretion processes, beaches being the most affected coastal land cover. Emphasis was placed on identification and description of coastline sites in which land was either continuously lost(erosion) or gained(accretion) during the studied time periods. These sites were defined as continuous unidirectional dynamic sites and were compared with previous knowledge about the geodynamics of Mexican coasts. Continuous unidirectional dynamic sites were distributed throughout the study area and within all land cover types, but predominantly corresponded to areas covered by mangroves in the states of Campeche and Nayarit. Finally, we found an intensification of coastal erosion-accretion processes over time;coastline change rates having duplicated between the earliest(1970/81–2005) and the two more recent(2005–2010, and 2010–2015) analysed time periods, with erosion rates for each corresponding period of –3 m/yr,–7.5 m/yr, and –7.3 m/yr,and accretion rates of 2.8 m/yr, 7.3 m/yr, and 6.9 m/yr, respectively. 展开更多
关键词 CHANGES in MEXICAN COASTLINE Mexico COAST EROSION COAST ACCRETION
Sea-level rise impact on the evolution of a microtidal Mediterranean coastline without human-made structures——a case of the Port aux Princes-Sidi Daoued coastline, Gulf of Tunis,NE-Tunisia 预览
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作者 Hanen Sa?di Fouad Zargouni 《海洋学报:英文版》 SCIE CAS CSCD 2019年第3期72-77,共6页
The evolution of the natural and pristine Mediterranean coastline Port aux Princes-Sidi Daoued(Gulf of Tunis,NE-Tunisia) is studied during the period of 1887–2010 on the basis of an ancient minute of bathymetry(1887)... The evolution of the natural and pristine Mediterranean coastline Port aux Princes-Sidi Daoued(Gulf of Tunis,NE-Tunisia) is studied during the period of 1887–2010 on the basis of an ancient minute of bathymetry(1887) and aerial photographs treated by numerical photogrammetric methods. Morphological changes of the coastline shows a general retreat despite the absence of the various anthropogenic actions. Adding to the drift currents and the currents of high energy that are generated by the N-W dominant waves along steeply sub-marine funds, the erosion is mainly due to the sea level rise which increased since the beginning of the 2000 s. The Port aux PrincesSidi Daoued coastline works as a single littoral cell limited by Jbel Korbous to the SW and the fishing harbor of Sidi Daoued to the N-E. 展开更多
关键词 Mediterranean COASTLINE erosion sea level rise LITTORAL cell GULF of TUNIS Tunisia
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内蒙古浑善达克沙地南缘^137Cs、^210Pbex复合示踪研究
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作者 胡云锋 张云芝 《地理学报:英文版》 SCIE CSCD 2019年第10期1655-1669,共15页
Wind-driven soil erosion results in land degradation, desertification, atmospheric dust, and sandstorms. The Hunshandake Sandy Land, an important part of the Two Barriers and Three Belts project, plays important roles... Wind-driven soil erosion results in land degradation, desertification, atmospheric dust, and sandstorms. The Hunshandake Sandy Land, an important part of the Two Barriers and Three Belts project, plays important roles in preventing desert and sandy land expansion and in maintaining local sustainability. Hence, assessing soil erosion and soil accumulation moduli and analyzing the dynamic changes are valuable. In this paper, Zhenglan Banner,located on the southern margin of the Hunshandake Sandy Land, was selected as the study area. The soil erosion and accumulation moduli were estimated using the ^137Cs and ^210Pbex composite tracing technique, and the dynamics of soil erosion and soil accumulation were analyzed during two periods. The results are as follows:(1) the regional ^137Cs reference inventory was 2123.5±163.94 Bq/m^2, and the regional ^210Pbex reference inventory was 8112±1787.62 Bq/m^2.(2) Based on the ^137Cs isotope tracing analysis, the erosion moduli ranged from –483.99 to 740.31 t·km^-2·a^-1. Based on the ^210Pbex isotope tracing analysis, the erosion moduli ranged from –441.53 to 797.98 t·km^-2·a^-1.(3) Compared with the earliest 50 years, the subsequent 50 years exhibited lower soil erosion moduli and accumulation moduli.Therefore, the activities of local sand dunes weakened, and the quality of the local ecological environment improved. The multi-isotope composite tracing technique combining the tracers ^137Cs and ^210Pbex has potential for similar soil erosion studies in arid or semiarid regions around the world. 展开更多
关键词 wind erosion isotope TRACING reference INVENTORY quantitative estimation SANDY land
化机浆碱回收中非过程元素氯和钾的来源、影响以及去除方法 预览
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作者 黄再桂 马平原 王爱荣 《中华纸业》 CAS 2019年第14期41-46,共6页
化机浆系统中非过程元素氯和钾主要来源是主原料(木材)、清水和副原料(化学品),其会在生产系统中积累,造成碱炉燃烧时碱灰熔点下降,进而加速锅炉受热面积灰和结焦,造成碱炉运行周期缩短,生产效率下降.氯含量累积升高也会造成系统中设备... 化机浆系统中非过程元素氯和钾主要来源是主原料(木材)、清水和副原料(化学品),其会在生产系统中积累,造成碱炉燃烧时碱灰熔点下降,进而加速锅炉受热面积灰和结焦,造成碱炉运行周期缩短,生产效率下降.氯含量累积升高也会造成系统中设备和管道的腐蚀.如何降低非过程元素氯和钾的积累成为急需解决的问题.一些大型浆厂近几年已有实际应用的除氯、钾系统,包括:析滤、蒸发/结晶、冷却结晶和离子交换等方法,而目前应用较多的是蒸发/结晶法. 展开更多
关键词 化机浆 碱回收炉 碱灰 腐蚀 去除率 回收率
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Erosion probability model of base-soil particle migration into agranular lter under local ow 预览
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作者 Yuan Wei Mei-li Zhan +3 位作者 Qing-fu Huang Jin-chang Sheng Yulong Luo Qing Zhou 《国际泥沙研究:英文版》 SCIE 2019年第5期455-460,共6页
To avoid soil erosion, lters often are installed in the downstream cross section of dams. However, the probability of piping failure and the lter effect both are related to the soil pore network. Previous erosion prob... To avoid soil erosion, lters often are installed in the downstream cross section of dams. However, the probability of piping failure and the lter effect both are related to the soil pore network. Previous erosion probability models for a base soil- lter system do not consider the effect of local ow. Therefore, in this study, an improved erosion probability model is established, in which the deviation between the main ow direction of the soil and the local ow direction in the lter was considered based on a previous model. The improved model was validated by numerical simulation. The erosion probability was found to affect the reasonable evaluation of lter effects and the optimal selection of lter thickness. The controlling con- striction size in a granular lter was increased to Dc* Dc5 with a lter thickness of 59 Dm. 展开更多
关键词 GRANULAR filter PORE network EROSION PROBABILITY LOCAL flow Deviation PROBABILITY
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东北漫川漫岗和山地丘陵黑土区侵蚀沟形态特征遥感分析 预览
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作者 李镇 秦伟 +4 位作者 齐志国 尚国琲 马庆涛 郭乾坤 殷哲 《农业工程学报》 EI CAS CSCD 北大核心 2019年第14期133-140,共8页
侵蚀沟形态特征反映其侵蚀发生发展的环境条件,探究侵蚀沟形态参数特征及空间分异规律对深入理解侵蚀沟的侵蚀进程具有重要意义。该文选择漫川漫岗和山地丘陵2个典型黑土地貌类型区,基于高分遥感影像(QuickBird(0.61m)、GeoEye-1(0.5m)... 侵蚀沟形态特征反映其侵蚀发生发展的环境条件,探究侵蚀沟形态参数特征及空间分异规律对深入理解侵蚀沟的侵蚀进程具有重要意义。该文选择漫川漫岗和山地丘陵2个典型黑土地貌类型区,基于高分遥感影像(QuickBird(0.61m)、GeoEye-1(0.5m)及Worldview 2(0.5m))和地形数据(ASTGTM2(30m分辨率)),采用目视解译法提取计算侵蚀沟沟长、沟宽、周长和面积等形态参数值,分析侵蚀沟形态特征;探究地形因子影响下侵蚀沟形态参数的分异规律。研究结果显示:1)2个典型区的各形态参数间存在显著性差异,漫川漫岗区侵蚀沟各形态参数均大于山地丘陵区;2)侵蚀沟形态呈现“细长状”,和漫川漫岗区相比,山地丘陵区侵蚀沟更细长,沟缘位置更复杂;3)侵蚀沟形态参数随坡度的增加总体上呈先增大后减小的趋势,在3°~6°范围内参数值达到最大,坡度越小侵蚀沟沟缘位置越复杂;坡向上,漫川漫岗区和山地丘陵区的侵蚀沟的形态参数值在SE或SW上值最大,说明阳坡或半阳坡侵蚀沟发育强烈。该研究结果对于侵蚀沟易发区确定及防治具有重要意义。 展开更多
关键词 遥感 侵蚀 形态特征 侵蚀沟 地形因子 漫川漫岗区 山地丘陵区
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钻井用浮箍结构冲蚀安全优化数值模拟研究 预览
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作者 陈新海 豆惠萍 +4 位作者 王乐顶 李立昌 李毅 王锐 杨恺 《安全与环境工程》 CAS 北大核心 2019年第1期170-176,共7页
针对固井过程中套管用浮箍、浮鞋等附件频频发生失效事故,开展固井浮箍、浮鞋冲蚀优化的数值模拟研究。通过建立浮箍流场CFD有限元模型,定量模拟研究不同阀芯开度下含有固相颗粒的多相流对浮箍阀体的冲蚀速率,建立了冲蚀速率与固相颗粒... 针对固井过程中套管用浮箍、浮鞋等附件频频发生失效事故,开展固井浮箍、浮鞋冲蚀优化的数值模拟研究。通过建立浮箍流场CFD有限元模型,定量模拟研究不同阀芯开度下含有固相颗粒的多相流对浮箍阀体的冲蚀速率,建立了冲蚀速率与固相颗粒含量、固相颗粒大小、阀芯开启度的关系曲线。结果表明:弹簧式浮箍在开启高度L大于或等于40mm,舌板式浮箍在阀板开启角度大于50°时,能使其冲蚀速率显著减小。 展开更多
关键词 固井 浮箍 冲蚀 安全优化 数值模拟
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宝钢1号高炉炉缸温度升高的治理
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作者 王波 陈永明 +1 位作者 宋文刚 王士彬 《炼铁》 北大核心 2019年第4期19-23,共5页
宝钢1号高炉2017年以来炉缸温度出现4次异常升高的现象,认为主要是炉体热负荷波动及崩滑料、炉前作业状况不稳定、处理上不够果断等引起的。通过采取改善炉缸状态消除局部不均匀侵蚀、优化炉前作业制度稳定铁口区工作状态、建立炉缸温... 宝钢1号高炉2017年以来炉缸温度出现4次异常升高的现象,认为主要是炉体热负荷波动及崩滑料、炉前作业状况不稳定、处理上不够果断等引起的。通过采取改善炉缸状态消除局部不均匀侵蚀、优化炉前作业制度稳定铁口区工作状态、建立炉缸温度异常预警机制等措施,高炉技术经济指标改善,同时炉缸温度处于安全、稳定受控范围。炉缸温度2号铁口测温点由最高的680℃下降至130℃,3号铁口测温点由最高的615℃下降至150℃。 展开更多
关键词 大型高炉 炉缸温度 侵蚀 操作制度 顺行 铁口
Determination of the particle load based on detailed suspended sediment measurements at a hydropower plant 预览
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作者 Anant Kumar Rai Arun Kumar 《国际泥沙研究:英文版》 SCIE 2019年第5期409-421,共13页
Suspended sediment particles contained in inflows of water systems of hydropower plants (HPPs) cause hydro-abrasive erosion of the hydraulic turbines and structures leading to significant maintenance costs, efficiency... Suspended sediment particles contained in inflows of water systems of hydropower plants (HPPs) cause hydro-abrasive erosion of the hydraulic turbines and structures leading to significant maintenance costs, efficiency reductions, and downtime. Relevant parameters such as suspended sediment concentration (SSC), particle size distribution (PSD), shape, and mineralogical composition were measured with an online multi-frequency acoustic instrument and based on manually taken samples from the end of the sand trap of the Toss HPP in the Himalayan region, India. In the laboratory, the samples were analyzed using the gravimetric method, laser diffraction, turbidity, dynamic digital image processing, scanning electron microscope, petrography analysis, energy-dispersive X-ray spectroscopy, and X-ray diffraction. The online instrument and the samples provided measurement results at a single point. To investigate vertical gradients in concentration and particle sizes, additional samples were collected 9 times at 7 relative water depths. The SSC, most particle sizes, and particle shape were found to be evenly distributed over depth except d90, i.e. the diameter which is not exceeded by 90% of the particle mass. d90 measured at 76% of the water depth was in the range of fine sand and was multiplied by 1.05 to obtain an average value representative for the entire depth. Improved methodologies to quantify both particle shape and size in an analytical model for hydro-abrasive erosion are proposed. Also, the PSD measuring performance of laser diffraction and dynamic imaging was studied and similar values of the median particle sizes were obtained from both instruments. Further, multi-frequency acoustic, turbidity and laser diffraction techniques were found suitable for SSC measurement at the test case HPP. 展开更多
关键词 Suspended sediment concentration Hydro-abrasive EROSION HYDROPOWER PARTICLE size distribution PARTICLE shape MINERALOGICAL composition
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