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Discussion on the Construction of Negotiation Mechanism of Cross-bounder Water Pollution Treatment in Changjiang River 被引量:9
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作者 陈坤 《Meteorological and Environmental Research》 CAS 2010年第12期91-95,共5页
In order to construct cooperation platform for the treatment of water pollution in Changjiang River,thoughts and revolution were performed from both central government and regional area two aspects.From the national l... In order to construct cooperation platform for the treatment of water pollution in Changjiang River,thoughts and revolution were performed from both central government and regional area two aspects.From the national level,Changjiang region water resources management cooperation counsel committee was constructed as the national cooperation platform;from the regional level,Changjiang region water resources management cooperation counsel committee was constructed as the platform of Changjiang cooperation platform.The two platforms built fine interaction mechanism to deal with the national water management and Changjiang regional water management. 展开更多
关键词 Changjiang River cross-boundary water pollution NEGOTIATION China
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图像中的声音表达--中国古代听松图的跨媒介阐释
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作者 刘坛茹 《中国文艺评论》 CSSCI 2024年第6期69-80,I0003,共13页
图像何以表现声音,是一个艺术跨媒介表达的问题。中国古代听松图通过强化主体的听觉性在场、“一主一仆”图式的“合唱队”效果、构图留白隐喻风孔、以题画诗弥补画面松声等手段,使图像的松声得以审美显现。并且,频繁使用临水听松、松... 图像何以表现声音,是一个艺术跨媒介表达的问题。中国古代听松图通过强化主体的听觉性在场、“一主一仆”图式的“合唱队”效果、构图留白隐喻风孔、以题画诗弥补画面松声等手段,使图像的松声得以审美显现。并且,频繁使用临水听松、松下士人图式,以音助圣,敞开自然的审美空间。此外,静听松风也是松声转化为遗音的过程,由实到虚,绵延回旋。对于听松图而言,与其说松声是通过画面空间表现的,不如说是由松声通过艺术动势,召唤空间、创造空间,以时间统领空间,从而完成了跨媒介的艺术表达。 展开更多
关键词 听松图 跨媒介 临水听松 遗音 艺术动势
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Self-Cross-Linked Tannin-Aminated Tannin Surface Coatings for Particleboard
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作者 Bengang Zhang Antonio Pizzi +2 位作者 Mathieu Petrissans Anelie Petrissans Colin Baptiste 《Journal of Renewable Materials》 EI 2023年第12期4097-4121,共25页
Aminated tannins were prepared by reacting mimosa condensed tannin extract with ammonia yielding the substitution of many,if not all of the tannin hydroxyl groups with–NH_(2)groups.A tannin-aminated tannin(ATT)partic... Aminated tannins were prepared by reacting mimosa condensed tannin extract with ammonia yielding the substitution of many,if not all of the tannin hydroxyl groups with–NH_(2)groups.A tannin-aminated tannin(ATT)particleboard coating was then prepared by reacting raw tannin extract with aminated tannin extract and thus cross-linking the two by substituting tannin’s hydroxyl groups with the–NH_(2)groups on the aminated tannin to form–NH-bridges between the two.The resulting particleboard coating gave encouraging results when pressed at 180℃for 3 min.Conversely,the system in which tannin was reacted/cross-liked with urea(ATU)by a similar amination reaction did not perform as well as the ATT system,and this even when a higher curing temperature and longer hot press time were used.In particular its water repellence was worse probably due to the presence of urea and such a system with lower reactivity.Nonetheless,substituting the tannin–OHs with the urea–NH_(2)groups appeared to also take place.ATT gave better results than ATU as regards water repellence and mechanical resistance as shown by the cross cut test.The ATT system was shown to be between 95%and 98%biosourced.The difference appeared to be due,by TMA analysis,to the much faster formation of the ATT hardened network leading to a better cross-linked polymer coating.The chemical species formed for both the ATT and ATU system were studied by MALDI ToF and CP MAS^(13)C NMR. 展开更多
关键词 Biocoatings PARTICLEBOARD aminated tannin cross-linked tannin-aminated tannin tannin-urea cross links water repellence cross cut test MALDI ToF ^(13)C NMR
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The diffusive fluxes of inorganic nitrogen across the intertidal sediment-water interface of the Changjiang Estuary in China 被引量:5
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作者 HOU Lijun LIU Min +3 位作者 XU Shiyuan LU Jianjian OU Dongni YU Jie 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第3期48-57,共10页
Ammonium and nitrate concentrations were analyzed in near-bottom water and pore water collected from ten stations of the intertidal flat of the Changjiang Estuary during April, July, November and February. The magnitu... Ammonium and nitrate concentrations were analyzed in near-bottom water and pore water collected from ten stations of the intertidal flat of the Changjiang Estuary during April, July, November and February. The magnitudes of the benthic exchange fluxes were determined on the basis of concentration gradients of ammonium and nitrate at the near-bottom water and interstitial water interface in combination with calculations of a modified Fick' s first law. Ammonium fluxes varied from - 5.05 to 1.43 μg/( cm^2·d) and were greatly regulated by the production of ammonium in surface sediments, while nitrate fluxes ranged from - 0. 38 to 1.36 μg/ ( cm^2·d) and were dominated by nitrate concentrations in the tidal water. It was found that ammonium was mainly released from sediments into water columns at most of stations whereas nitrate was mostly diffused from overlying waters to intertidal sediments. In total, 823.75 t/a ammonium-N was passed from intertidal sediments to water while about 521.90 t/a nitrate-N was removed from overlying waters to intertidal sediments. This suggests that intertidal sediments had the significant influence on modulating inorganic nitrogen in the tidal water. 展开更多
关键词 AMMONIUM NITRATE sediment - water interface intertidal flat Changjiang Estuary
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Study on Filling Cross-Roadway in Fully-Mechanized Coal Faces with High Water-Content Material 被引量:1
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作者 周华强 王光伟 +2 位作者 雷文成 曲庆贺 李峰 《Journal of China University of Mining and Technology》 2001年第2期113-117,共5页
A new method using high water content material to mechanically fill cross roadways to form artificial bottom for coal faces was introduced. The reasonable determination of filling range, the optimization of the compou... A new method using high water content material to mechanically fill cross roadways to form artificial bottom for coal faces was introduced. The reasonable determination of filling range, the optimization of the compounding ratio of high water content material, and the filling technique were discussed in detail. This new method has been spread after industrial testing in Baodian Colliery. Compared with the traditional method, the manual wooden chock method, the new one decreases about 40% of the filling range and cost in dealing every one set of cross roadway in the testing condition. 展开更多
关键词 fully mechanized coal face cross roadway high water content material FILLING artificial bottom
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Water Vapor Transport and Cross-Equatorial Flow over the Asian-Australia Monsoon Region Simulated by CMIP5 Climate Models 被引量:7
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作者 宋亚娟 乔方利 +1 位作者 宋振亚 姜春飞 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第3期726-738,共13页
The summer mean water vapor transport (WVT) and cross-equatorial flow (CEF) over the Asian- Australian monsoon region simulated by 22 coupled atmospheric-oceanic general circulation models (AOGCMs) from the Worl... The summer mean water vapor transport (WVT) and cross-equatorial flow (CEF) over the Asian- Australian monsoon region simulated by 22 coupled atmospheric-oceanic general circulation models (AOGCMs) from the World Climate Research Programme's Coupled Model Intercomparison Project Phase 5 (CMIP5) were evaluated. Based on climatology of the twentieth-century simulations, most of models have a reason- ably realistic representation of summer monsoon WVT characterized by southeast water vapor conveyor belt over the South Indian Ocean and southwest belt from the Arabian Sea to the East Asian. The correlation coefficients between NCEP reanalysis and simulations of BCC-CSMI-1, BNU-ESM, CanESM2, FGOALS-s2, MIROC4h and MPI-ESM-LR are up to 0.8. The simulated CEF depicted by the meridional wind along the equator includes the Somali jet and eastern CEF in low atmosphere and the reverse circulation in upper atmosphere, which were generally consistent with NCEP reanalysis. Multi-model ensemble means (MME) can reproduce more reasonable climatological features in spatial distribution both of WVT and CEF. Ten models with more reasonable WVT simulations were selected for future projection studies, including BCC- CSMI-1, BNU-ESM, CanESM2, CCSM4, FGOALS-s2, FIO-ESM, GFDL-ESM2G, MRIOCS, MPI-ESM-LR and NorESM-1M. Analysis based on the future projection experiments in RCP (Representative Concentra- tion Pathway) 2.6, RCP4.5, RCP6 and RCP8.5 show that the global warming forced by different RCP scenarios will results in enhanced WVT over the Indian area and the west Pacific and weaken WVT in the low latitudes of tropical Indian Ocean. 展开更多
关键词 CMIP5 AOGCMs water vapor transport cross-equatorial flow future projection
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Sacrificial piles as a countermeasure against local scour around underwater pipelines
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作者 Forough Raeisi Seyed Mohammad Ali Zomorodiann +1 位作者 Masih Zolghadr Hazi Mohammad Azamathulla 《Water Science and Engineering》 EI CAS CSCD 2024年第2期187-196,共10页
Local scour around pipelines crossing rivers or in marine environments is a significant concern.It can lead to failure of the pipelines resulting in environmental side effects and economic losses.This study developed ... Local scour around pipelines crossing rivers or in marine environments is a significant concern.It can lead to failure of the pipelines resulting in environmental side effects and economic losses.This study developed an experimental method to reduce local scour around pipelines with a steady flow of clear water by installing cylindrical and cubical sacrificial piles.Three sizes of sacrificial piles were examined in a linear arrangement.Sacrificial piles were installed on the upstream side of the pipeline at three distances.Maximum scour depth reduction rates below the pipeline were computed.The results showed that sacrificial piles could protect a pipeline from local scour.A portion of scoured sediment around the sacrificial piles was deposited beneath the pipeline.This sediment accumulation reduced the scour depth beneath the pipeline.Analysis of the experimental results demonstrated that the size of piles(d),the spacing between piles,and the distance between the pipe and piles(Xp)were the variables that reduced the maximum scour beneath the pipeline with a diameter of D.For the piles with d=0.40D and 0.64D,X_(p)=4OD was the optimal distance to install a group of piles,and cubical piles could mitigate scour more effectively than cylindrical piles under similar conditions.For the piles with d=D,the greatest reduction in scour depth was achieved at X_(p)=50D with any desired spacings between piles,and cylindrical piles in this dimension could protect the pipeline against scour more effectively than cubical piles. 展开更多
关键词 Clear water River crossing pipeline Local scour Self-burial process Sediment transport
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基于DPSIR-对称交互熵的泰安市水—城地人产系统协调性评价
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作者 潘慧民 门宝辉 +3 位作者 王红瑞 李一阳 李永坤 王丽晶 《水电能源科学》 北大核心 2024年第5期80-83,18,共5页
为将四水四定落到实处,构建了基于DPSIR-对称交互熵的水—城地人产系统评价模型,通过构建山东省泰安市评价指标体系,开展协调性发展综合评价,进而建立耦合协调度模型评价各子系统间发展协调性。研究表明,各子系统综合评价值呈现波动上... 为将四水四定落到实处,构建了基于DPSIR-对称交互熵的水—城地人产系统评价模型,通过构建山东省泰安市评价指标体系,开展协调性发展综合评价,进而建立耦合协调度模型评价各子系统间发展协调性。研究表明,各子系统综合评价值呈现波动上升趋势,其中状态(S)和响应(R)子系统波动上升趋势最为稳定,最不稳定的为压力(P)子系统;按照历年系统耦合协调度将2006年以来泰安市水—城地人产系统发展划分为过渡阶段(2006~2010年)、协调发展阶段(2011~2019年)、高质量发展阶段(2020年以后);宁阳县、东平县协调度仍有待提高,未来应当着重推进泰安市水网建设、供、用水结构优化和产业结构升级等工作。研究结果可为泰安市国土空间规划及水利高质量发展提供支持。 展开更多
关键词 四水四定 DPSIR模型 对称交互熵 耦合协调度模型 协调性评价
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交联型聚(联苯-哌啶)阴离子交换膜制备与电解槽性能研究
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作者 张安然 李黎明 +3 位作者 马颖 肖文涛 李非凡 张玉广 《低碳化学与化工》 CAS 北大核心 2024年第9期82-87,96,共7页
为制备出同时具备高电导率和高稳定性的阴离子交换膜(AEM),以1,6-二溴己烷为交联剂,采用浇铸法制备了不同交联度的交联型聚(联苯-哌啶)AEM(PBP-Pip-x%膜,x代表交联度,取值分别为5、10和15)。分别采用^(1)H NMR和AFM对PBP-Pip-x%膜的结... 为制备出同时具备高电导率和高稳定性的阴离子交换膜(AEM),以1,6-二溴己烷为交联剂,采用浇铸法制备了不同交联度的交联型聚(联苯-哌啶)AEM(PBP-Pip-x%膜,x代表交联度,取值分别为5、10和15)。分别采用^(1)H NMR和AFM对PBP-Pip-x%膜的结构和形貌等进行了表征,并以未交联的聚(联苯-哌啶)AEM(PBP-Pip膜)作为对照组,研究了PBP-Pip-x%膜的性能。结果表明,PBP-Pip-15%膜具有更好的微相分离结构,其电导率(99.14 mS/cm)较PBP-Pip膜的电导率(49.89 mS/cm)明显提高。PBP-Pip-15%膜表现出较好的碱稳定性,在1 mol/L KOH溶液中于80℃浸泡300 h后,其电导率为37.50 mS/cm,电导率保留率为79.73%。在设定条件(温度为80℃、1 mol/L KOH溶液中和小室电压为2.0 V)下,PBP-Pip-15%膜的电流密度为0.5 A/cm^(2),并且在100 h内稳定性未发生明显改变。 展开更多
关键词 交联结构 聚(联苯-哌啶) 阴离子交换膜 水电解技术
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矿井涌水量预测方法及对比分析-以新疆东沟煤矿为例
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作者 周全超 王丹丹 +5 位作者 党志伟 霍超 苏杰 刘春宇 顾雷雨 李继升 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第S01期211-220,共10页
矿井涌水量的预测对煤矿的安全生产具有重要意义。水文地质参数的准确选择、计算方法的选择对矿井涌水量的准确预测影响巨大,同时考虑到矿井开采实际,涌水量不是从开采初期就稳定不变的,而是动态变化的。为提升涌水量预测的准确度,更好... 矿井涌水量的预测对煤矿的安全生产具有重要意义。水文地质参数的准确选择、计算方法的选择对矿井涌水量的准确预测影响巨大,同时考虑到矿井开采实际,涌水量不是从开采初期就稳定不变的,而是动态变化的。为提升涌水量预测的准确度,更好地为煤矿开采服务,在分析新疆东沟煤矿地质及水文地质条件,选取准确水文地质参数的基础上,选择了2种适用于东沟煤矿的涌水量预测方法进行了对比分析。计算结果表明:①非稳定流释水-断面流法计算得到的涌水量呈现动态变化特征,采掘强度稳定后,变化幅度变小,最后趋于稳定;②采用大井法、非稳定流释水-断面流法计算得到的预测涌水量分别为3396、599.87~612.9 m^(3)/d与实际涌水量480 m^(3)/d分别相差607.5%>24.97%~27.69%;③根据矿井实际开采产生的涌水量数据验证分析,采用非稳定流释水-断面流法计算得到的涌水量与实际开采产生的涌水量基本吻合,涌水量预测结果的准确度依次为非稳定流释水-断面流法>大井法;④在资料充足、参数准确的情况下,建议优先选择非稳定流释水-断面流法计算涌水量,在补水边界条件差且符合大井法要求的条件下建议首先选用大井法。本次计算结果一方面充分验证了非稳定流释水-断面流法的准确度,另一方面为煤矿矿井涌水量计算提供了借鉴,同时也为东沟煤矿的安全生产提供了数据支撑。 展开更多
关键词 矿井涌水量预测 大井法 非稳定流释水-断面流法 小东沟煤矿
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Vegetation Formation in Estuarine Tidal Flats: Influences of Basin Scale and River-Crossing Structures of the Eight Rivers of Ise Bay in Mie and Aichi Prefectures, Japan
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作者 Korehisa Kaneko Seiich Nohara 《Open Journal of Ecology》 2014年第15期974-988,共15页
In this study, we examined the influences of the differences in basin scale and river-crossing structures of 8 rivers of Ise Bay in Mie and Aichi Prefectures, Japan on the vegetation in the estuarine tidal flats of th... In this study, we examined the influences of the differences in basin scale and river-crossing structures of 8 rivers of Ise Bay in Mie and Aichi Prefectures, Japan on the vegetation in the estuarine tidal flats of these rivers. The dominant plant communities of the estuarine tidal flats formed from rivers of large-scale river basins (exceeding 300 km2) were determined. In the Miya River, the dominant plant community was the Suaeda maritima and Artemisia fukudo community. In the Kushida River, the dominant plant community was composed of Phacelurus latifolius, Artemisia fukudo, Phragmites australis, and bamboo. In the Kumozu River, the dominant community was composed of the coastal plants Calystegia soldanella, Lathyrus japonicus, and Carex pumila and the exotic plant of Lolium multiflorum. The plant community of Suzuka River was dominated by the exotic plant of Eragrostis curvula. Among the estuarine tidal flats influenced by a small-scale river basin (50 km2 or less), the plant community of Shinbori River (Fukue tidal flat) was dominated by Suaeda maritima, and the plant communities of the Shio and Harai Rivers were dominated by Phragmites australis. The plant community of Tanaka River was dominated by Phragmites australis and coastal plants. Regarding the relationship between the vegetation and the river environment for each study site, we hypothesised that in a large basin area with few structures crossing the river, the river water catchment in the estuary after heavy rains caused large areas of disturbance and formed bare land, providing suitable habitat for an annual salt marsh plant community. In contrast, in cases with many structures crossing the river, a stable channel, an excavated riverbed and the suppression of runoff and the resulting disturbance of the estuary, flooding did not occur during high tide. Moreover, we hypothesised that in a small basin with many structures crossing the river, disturbance to the estuary was not likely, and the perennial salt marsh plant community of Phragmites australis would be widely distributed, except for a river type such as the Shinbori River, in which tide and river flow were managed by a final closure. 展开更多
关键词 Annual SALT MARSH PLANT PERENNIAL SALT MARSH PLANT RIVER-crossing Structure water Level River Basin
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HEC-RAS模型在南水北调中线洪水推求中的运用
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作者 陈嘉敏 郑晓阳 《陕西水利》 2024年第11期21-23,27,共4页
为提高南水北调中线工程防洪度汛科学性,提升防汛抢险决策水平,有效计算交叉河流过流情况,最大限度减少南水北调交叉河道洪水造成的人员伤亡和工程损失,保障工程正常运行,开展南水北调中线工程交叉河道水文计算工作非常有必要。以南水... 为提高南水北调中线工程防洪度汛科学性,提升防汛抢险决策水平,有效计算交叉河流过流情况,最大限度减少南水北调交叉河道洪水造成的人员伤亡和工程损失,保障工程正常运行,开展南水北调中线工程交叉河道水文计算工作非常有必要。以南水北调中线交叉河道净肠河倒虹吸河道计算为例,运用HEC-RAS水动力模型对净肠河倒虹吸河道水文复核,根据24小时洪水情况,对交叉河道断面部位洪水流量及水位进行计算,复核验算结论超标洪水问题,为南水北调工程防洪度汛提供信息支撑,以期对其他类似工程科学预防,避免水毁、减小损失能够有所帮助。 展开更多
关键词 南水北调 交叉河道 水动力模型 洪水计算
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GPS-RTK联合数字测深仪在凤河河道横断面测量中的应用
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作者 林方建 《陕西水利》 2024年第5期159-161,165,共4页
以台山市新昌水凤河河道横断面测量为例,由于水下地形复杂,传统的河道横断面测量方法效率低、精度差,已无法满足现代水利建设的需要。为了能够提高河道横断面的测量精度和效率,减少误差,采用GPS RTK技术联合测深仪进行河道横断面测量,... 以台山市新昌水凤河河道横断面测量为例,由于水下地形复杂,传统的河道横断面测量方法效率低、精度差,已无法满足现代水利建设的需要。为了能够提高河道横断面的测量精度和效率,减少误差,采用GPS RTK技术联合测深仪进行河道横断面测量,可以快速、准确地获取凤河河道横断面的位置坐标、水深、高程等数据。通过两种技术的联合应用,实现对新昌水(凤河)河道横断面的精确测量,为新昌水(凤河)治理工程的设计和建设提供准确的数据支持。 展开更多
关键词 GPS RTK 测深仪 河道横断面测量 新昌水(凤河)
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HEC-RAS模型在河道治理工程水面线推求中的应用
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作者 张冬梅 潘安琪 陈吼 《云南水力发电》 2024年第6期138-140,共3页
为掌握山区复杂流态河流暴雨洪水特性,以吴上湾河大埠口村段河道治理工程为例,利用HEC-RAS软件构建迭代推演水面线分析模型,并结合流域特征值及设计洪水成果,模拟获得控制断面治理前后10年一遇洪水条件下的河道水面线数据。分析结果表明... 为掌握山区复杂流态河流暴雨洪水特性,以吴上湾河大埠口村段河道治理工程为例,利用HEC-RAS软件构建迭代推演水面线分析模型,并结合流域特征值及设计洪水成果,模拟获得控制断面治理前后10年一遇洪水条件下的河道水面线数据。分析结果表明:治理前河道滩地上沙场侵占行洪断面,导致河道水位壅高。通过主河槽扩挖补偿和混凝土挡土墙护岸等措施治理后,河道流速降低、行洪能力增加。HEC-RAS软件对于天然河道复杂流态水文水力计算具有较强适用性,推求数据合理可信。 展开更多
关键词 行洪断面 设计洪水 水面线 HEC-RAS模型
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Three-dimensional hydrodynamic model of Xiamen waters 被引量:5
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作者 WenShenghui CaiSong +1 位作者 TangJunjian CaiQifu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2003年第2期151-170,共20页
A semi-implicit and Eulerian - Lagrangian finite difference method for three-dimensionalshallow flow has been extended to a more complete system of equations incorporating second-moment turbulence closure model and tr... A semi-implicit and Eulerian - Lagrangian finite difference method for three-dimensionalshallow flow has been extended to a more complete system of equations incorporating second-moment turbulence closure model and transport equations of salinity and temperature. The simulation for flooding and drying of mudflats has been improved. The model is applied to Xiamen waters. Based on extensive survey data, water level elevation, temperature and salinity field along the eastern open boundary and at the Jiulong River inlets and runoffs are analyzed, specified and calibrated. The computed results show good agreement with the measured data, reproduce flooding, emergence of large and complex mudflat region. 展开更多
关键词 Semi-implicit finite difference scheme Eulerian - Lagrangian approach three-dimensional shallow water flow Xiamen waters
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Using irrigation intervals to optimize water-use efficiency and maize yield in Xinjiang,northwest China 被引量:7
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作者 Guoqiang Zhang Dongping Shen +10 位作者 Bo Ming Ruizhi Xie Xiuliang Jin Chaowei Liu Peng Hou Jun Xue Jianglu Chen Wanxu Zhang Wanmao Liu Keru Wang Shaokun Li 《The Crop Journal》 SCIE CAS CSCD 2019年第3期322-334,共13页
Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yiel... Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yield and water use efficiency(WUE) of high-yield maize under conditions of mulching and drip irrigation.A field experiment was conducted using three irrigation intervals in 2016: 6, 9, and 12 days(labeled D6, D9, and D12) and five irrigation intervals in 2017: 3, 6, 9, 12, and 15 days(D3, D6, D9, D12, and D15).In Xinjiang, an optimal irrigation quota is 540 mm for high-yield maize.The D3, D6, D9, D12, and D15 irrigation intervals gave grain yields of 19.7, 19.1–21.0, 18.8–20.0, 18.2–19.2, and 17.2 Mg ha^-1 and a WUE of 2.48, 2.53–2.80, 2.47–2.63, 2.34–2.45, and 2.08 kg m-3, respectively.Treatment D6 led to the highest soil water storage, but evapotranspiration and soil-water evaporation were lower than other treatments.These results show that irrigation interval D6 can help maintain a favorable soil-moisture environment in the upper-60-cm soil layer, reduce soilwater evaporation and evapotranspiration, and produce the highest yield and WUE.In this arid region and in other regions with similar soil and climate conditions, a similar irrigation interval would thus be beneficial for adjusting soil moisture to increase maize yield and WUE under conditions of mulching and drip irrigation. 展开更多
关键词 Irrigation frequency Soil moisture MAIZE High yield(>15 Mg ha^(-1)) water use efficiency
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Layer regrouping for water-flooded commingled reservoirs at a high water-cut stage 被引量:2
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作者 Chuan-Zhi Cui Jian-Peng Xu +3 位作者 Duan-Ping Wang Zhi-Hong Liu Ying-song Huang Zheng-Ling Geng 《Petroleum Science》 SCIE CAS CSCD 2016年第2期272-279,共8页
Layer regrouping is to divide all the layers into several sets of production series according to the physical properties and recovery percent of layers at high water-cut stage, which is an important technique to impro... Layer regrouping is to divide all the layers into several sets of production series according to the physical properties and recovery percent of layers at high water-cut stage, which is an important technique to improve oil recovery for high water-cut multilayered reservoirs. Dif- ferent regroup scenarios may lead to different production performances. Based on unstable oil-water flow theory, a multilayer commingled reservoir simulator is established by modifying the production split method. Taking into account the differences of layer properties, including per- meability, oil viscosity, and remaining oil saturation, the pseudo flow resistance contrast is proposed to serve as a characteristic index of layer regrouping for high water-cut multilayered reservoirs. The production indices of multi- layered reservoirs with different pseudo flow resistances are predicted with the established model in which the data are taken from the Shengtuo Oilfield. Simulation results show that the pseudo flow resistance contrast should be less than 4 when the layer regrouping is implemented. The K-means clustering method, which is based on the objec- tive function, is used to automatically carry out the layer regrouping process according to pseudo flow resistances. The research result is applied to the IV-VI sand groups of the second member of the Shahejie Formation in the Shengtuo Oilfield, a favorable development performance is obtained, and the oil recovery is enhanced by 6.08 %. 展开更多
关键词 water-flooded reservoirs Layer regrouping.Flow resistance - High water cut Reservoir simulation
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The Coupling Coordination Evolution Research of Economy - Ecology - Society System in Xinjiang:Based on the Interaction Perspective of Water Resources 被引量:1
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作者 Chen Junke Li Hong +1 位作者 Wang Xibo Ma Yongren 《Meteorological and Environmental Research》 CAS 2017年第5期73-77,共5页
Under the water resources perspective,coupling coordination of economy-ecology-society system in Xinjiang was taken as the research object. By building the coupling evaluation index system of the water resources-econo... Under the water resources perspective,coupling coordination of economy-ecology-society system in Xinjiang was taken as the research object. By building the coupling evaluation index system of the water resources-economy-ecology-society system,quantitative evaluation and analysis of the coupling coordination of the water resources-economy-ecology-society system from 2001 to 2014 were conducted. The results showed that benefit indexes of economic system and social system grew rapidly,while benefit indexes of water resources system and ecosystem fluctuated smoothly from 2001 to 2014; coupling state of the whole system was at rival stage,and coupling coordination was reluctant coordination type,and the coupling index was slightly higher than the coupling coordination index. Moreover,it showed that the more the coupling systems,the lower indices of coupling and the coupling coordination. 展开更多
关键词 water resources - ECONOMY - ECOLOGY - SOCIETY SYSTEM COUPLING coordination Evolution XINJIANG
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PERVAPORATION PROPERTIES OF PDMS MEMBRANES CURED WITH DIFFERENT CROSS-LINKING REAGENTS FOR ETHANOL CONCENTRATION FROM AQUEOUS SOLUTIONS 被引量:5
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作者 李继定 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2009年第4期533-542,共10页
Ethanol perm-selective PDMS/PVDF composite membranes were prepared by curing polydimethylsiloxane (PDMS) with various cross-linking reagents,such as tetraethoxylsilane(TEOS),γ-aminopropyltriethoxylsilane(APTEOS), phe... Ethanol perm-selective PDMS/PVDF composite membranes were prepared by curing polydimethylsiloxane (PDMS) with various cross-linking reagents,such as tetraethoxylsilane(TEOS),γ-aminopropyltriethoxylsilane(APTEOS), phenyltrimethoxylsilane(PTMOS) and octyltrimethoxylsilane(OTMOS) as well.The cross-linking density and surface properties of the PDMS active layer were adjusted by varying cross-linking reagents.The pervaporation performance of PDMS membranes cured with different cross-linking reagents was investig... 展开更多
关键词 cross-linking PDMS Mass transfer coefficient ETHANOL/water PERVAPORATION
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仿生水-空跨介质航行器控制系统研究 被引量:1
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作者 李宏源 邹勇 +2 位作者 邹宇城 吕鹏宇 段慧玲 《舰船科学技术》 北大核心 2023年第20期79-82,共4页
随着海洋技术与装备的快速发展,对海上无人装备的作战能力提出更高要求。为了有效提高无人系统的跨域作战能力,亟需突破多模态跨域控制技术,实现多系统间的协同配合。基于上述背景,本文首先对国内外跨介质航行器的跨域控制技术进行梳理... 随着海洋技术与装备的快速发展,对海上无人装备的作战能力提出更高要求。为了有效提高无人系统的跨域作战能力,亟需突破多模态跨域控制技术,实现多系统间的协同配合。基于上述背景,本文首先对国内外跨介质航行器的跨域控制技术进行梳理,并提出适用于仿生水-空跨介质航行器的两栖多模态切换控制技术和复杂海洋环境下的自抗扰控制技术。研究表明,该技术能够有效提升航行器跨域控制的鲁棒性与自抗扰能力。其次,初步设计与跨域控制技术相匹配的仿生水-空跨介质航行器软硬件系统,并论证航行器跨域控制系统的可行性。最后,对本文提出的控制技术进行总结分析,为新型水-空跨介质航行器的跨域控制技术研究提供新的思路。 展开更多
关键词 仿生水-空跨介质航行器 两栖多模态跨域运动控制 自抗扰控制 软硬件系统
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