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Formation of the Yalong Downstream Terraces in the SE Tibetan Plateau and Its Implication for the Uplift of the Plateau 被引量:4
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作者 HE Zexin ZHANG Xujiao +3 位作者 QIAO Yansong BAO Shuyan LU Chunyu HE Xiangli 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第2期542-560,共19页
The Yalong River is an important river that runs across the abruptly changing terrain of the SE Tibetan Plateau. The terraces and Quaternary sediments in its valleys preserve the information of tectonic uplift, climat... The Yalong River is an important river that runs across the abruptly changing terrain of the SE Tibetan Plateau. The terraces and Quaternary sediments in its valleys preserve the information of tectonic uplift, climate changes, and landform evolution since the Middle Pleistocene. Based on geomorphological, sedimentological, and chronological investigations, 6-8 terraces are identified in the lower reaches of Yalong catchment and its tributary--the Anning River. The electron spin resonance (ESR) or optically stimulated luminescence (OSL) data on the alluvial sediments in the upper portion of terraces indicate that they formed in 1.10, 0.90, 0.72, 0.06-0.04, 0.03-0.02, and 0.01 Ma. Tectonic uplift and the climatic cycle controlled the formation of the Yalong River terraces. The former dominated the dissection depths and incision rates, whereas the latter controlled the transformation between accumulation, which developed during the glacial period, and incision, which developed during the glacial-interglacial transition. The Yalong downstream incised rapidly from 1.10 to 0.72 Ma and rapidly from 0.06 Ma until the present; the terraces developed during these two periods. The incision rates in space during the two periods indicate the uplifting extent of the Jinpingshan area, which decreases toward the east and the south. The results reveal two rapidly uplifting stages in the SE Tibetan Plateau, including an accelerated uplifting since 0.06 Ma. Since the Middle Pleistocene, the tectonic uplift of the SE and NE parts of the Tibetan Plateau is synchronous, according to the same development stages of the river terraces of the Yalong downstream and the Yellow River in the Lanzhou area of the NE Tibetan Plateau. The difference in the horizontal displacement between the Xianshuihe Fault and the Anninghe Fault bend resulted in the rapid uplift of the Jinpingshan area. The incision rate for the spatial distribution of the Yalong downstream is the geomorphologicai response of crustal shortening and uplift differences in the SE margin block of the Tibetan Plateau. The southeastward diffusion process of the Tibetan Plateau was recorded. 展开更多
关键词 Yalong downstream Anning River river terrace tectonic uplift climate change the Tibetan Plateau
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Downstream Development of Baroclinic Waves in the Midlatitude Jet Induced by Extratropical Transition: A Case Study 被引量:3
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作者 CHEN Hua 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第4期528-540,共13页
This study uses eddy kinetic energy analysis and a targeting method to investigate how an extratropical transition(ET)event induced downstream development(the modification of the midlatitude flow downstream of the ... This study uses eddy kinetic energy analysis and a targeting method to investigate how an extratropical transition(ET)event induced downstream development(the modification of the midlatitude flow downstream of the ET system) in the midlatitude jet environment. The downstream development showed distinct characteristics of "coupling development" and being "boundary-trapped". Eddies(potential disturbances) first developed at the upper levels, and these triggered lower-level eddy development, with all eddies decaying away from the tropopause and the surface. Thereafter, a lower-level eddy caught up with the upper-level eddy ahead of it, and they coupled to form a cyclone extending through the whole troposphere. Vertical ageostrophic geopotential flux may be a crucial dynamic factor throughout the eddy's lower-level growth, boundary-trapping,and coupling development.Together with barotropic conversion, the ageostrophic geopotential fluxes that were transported from Hurricane Fabian(2003) to the midlatitudes by the outflow led to downstream ridge development in the upper-level jet. The strong downstream advection of eddy kinetic energy in the exit region of the jet streak triggered downstream trough development. The well-known ridge–trough couplet thus formed. The vertical ageostrophic fluxes that were transported downward from the developed upper-level systems converged near the surface and resulted in lower-level eddy growth. Baroclinic conversion was negligible near the boundaries, while it was the main source of eddy kinetic energy at mid-levels. In the upper-level jet, potential energy was converted to the mean kinetic energy of the jet, which in turn was converted to eddy kinetic energy through barotropic conversion. 展开更多
关键词 downstream development ageostropic geopotential flux boundary-trapping coupling development
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Climate-Vegetation Coverage Interactions in the Hengduan Mountains Area, Southeastern Tibetan Plateau, and Their Downstream Effects
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作者 Congxi FANG Jinlei CHEN +4 位作者 Chaojun OUYANG Lu WANG Changfeng SUN Quan ZHANG Jun WEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期701-716,共16页
Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in ... Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in the world.This study,using multisource datasets(including satellite data and meteorological observations and reanalysis data)revealed the mutual feedback mechanisms between changes in climate(temperature and precipitation)and vegetation coverage in recent decades in the Hengduan Mountains Area(HMA)of the southeastern TP and their influences on climate in the downstream region,the Sichuan Basin(SCB).There is mutual facilitation between rising air temperature and increasing vegetation coverage in the HMA,which is most significant during winter,and then during spring,but insignificant during summer and autumn.Rising temperature significantly enhances local vegetation coverage,and vegetation greening in turn heats the atmosphere via enhancing net heat flux from the surface to the atmosphere.The atmospheric heating anomaly over the HMA thickens the atmospheric column and increases upper air pressure.The high pressure anomaly disperses downstream via the westerly flow,expands across the SCB,and eventually increases the SCB temperature.This effect lasts from winter to the following spring,which may cause the maximum increasing trend of the SCB temperature and vegetation coverage in spring.These results are helpful for estimating future trends in climate and eco-environmental variations in the HMA and SCB under warming scenarios,as well as seasonal forecasting based on the connection between the HMA eco-environment and SCB climate. 展开更多
关键词 Hengduan Mountains Area normalized difference vegetation index climate change net heat flux downstream effects
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Effects of Effluent from a Dumpsite on the Physicochemical Properties of River Achichum in Bamendakwe, Northwest Cameroon
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作者 Mofor Nelson Alakeh Keuwo Tiayong Francois +2 位作者 Nchofua Festus Biosengazeh Mikwa Cyprian Chunkang Njoyim Estella Buleng Tamungang 《Journal of Environmental Protection》 2024年第9期934-947,共14页
This study was aimed to assess the effects of effluent from a dumpsite on the physicochemical properties of river Achichum in Bamendakwe in the Bamenda I municipality, Northwest Region of Cameroon. The quality of wate... This study was aimed to assess the effects of effluent from a dumpsite on the physicochemical properties of river Achichum in Bamendakwe in the Bamenda I municipality, Northwest Region of Cameroon. The quality of water used for domestic purposes by the population of this area is mostly appreciated through its organoleptic assessment while no attention is paid to the physicochemical and microbiological properties. Samples (upstream, effluent, and downstream) were collected in the months of September 2022 and February 2023 and examined for organoleptic, physicochemical and bacteriological characteristics using standard methods. The river was contaminated to different extents by nitrates (28.56 - 149.91 mg/L), sulphates (246.89 - 725.42 mg/L) and heavy metals (0.01 - 0.04 mg/L for lead and 0.98 - 2.15 mg/L for aluminum). This contamination could be due to an inflow of the untreated effluent into the river. The river contained a high pollution level of lead and aluminum. Bacteriological investigations revealed that all the analyzed samples from the river contained indicators of faecal pollution such as Enterobacteria spp., E. coli, Streptococcus spp., Salmonella spp., Shigella spp., Staphylococcus spp. and Vibrio spp. Consequently, its utilization exposes consumers to health risks. Thus, water from the river should be treated prior to consumption. 展开更多
关键词 EFFLUENT UPSTREAM downstream Water Quality Faecal Contamination Bamendakwe
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Interaction between the Wilms tumour factor-1 element in the promoter of Amh and a downstream enhancer is required for a strong expression of the gene in pre-pubertal sertoli cells 被引量:1
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作者 David W. Dresser 《American Journal of Molecular Biology》 2013年第3期165-172,共8页
Amh (anti-Müllerian hormone) is a single copy gene which is expressed strongly in Sertoli cells in the foetal testis and participates in the onset of sexual differentiation. Its promoter driving the expression of... Amh (anti-Müllerian hormone) is a single copy gene which is expressed strongly in Sertoli cells in the foetal testis and participates in the onset of sexual differentiation. Its promoter driving the expression of a reporter gene (d2EGFP) has been used to analyse the role of certain defined putative elements and a downstream enhancer element in gene expression. These experiments were carried out in vitro using a line of pre-pubertal mouse Sertoli cells, transienly transfected with circular DNA constructs with variously mutated promoter elements. A downstream enhancer element, situated immediately 3’ of the polyadenylation (PA) signal for Amh, has been inserted in an equivalent position in the d2EGFP construct. When the Amh promoter is unmodified, the downstream enhancer (DE) is positively associated with a large increase in EGFP expression. This is at least partly the consequence of an increased rate of expression by individual cells. Experiments using variously truncated Amh promoters indicate that an upstream region (-214 to -336) may play a minor role in facilitating enhancement. However mutation of the Wilms tumour factor-1 element, situated between the tata box and the start of translation, results in an almost complete suppression of enhancement. 展开更多
关键词 Mouse Cell Lines In Vitro AMH PROMOTER SMAT Pre-Pubertal Sertoli downstream ENHANCER Wilms Tumour Factor ELEMENT
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The analysis on reservoir sediment deposition and downstream river channel scouring after impoundment and operation of TGP 被引量:1
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作者 Lu Jinyou Huang Yue Wang Jun 《Engineering Sciences》 EI 2011年第3期113-120,共8页
According to the measured data after impoundment and operation of the Three Gorges Reservoir,the reservoir sediment deposition and downstream river channel scouring are described briefly and compared with the research... According to the measured data after impoundment and operation of the Three Gorges Reservoir,the reservoir sediment deposition and downstream river channel scouring are described briefly and compared with the research results achieved in the demonstration stage.It is indicated through analysis that the reservoir sediment deposition and downstream river channel scouring during 8-year impoundment and operation are still within the original forecast,so the original forecasting results are feasible.The further observation and comparison should be conducted because the comparison between the observed data and the original forecast is not so sufficient in time and the prototype observation and related research work should be strengthened in the future. 展开更多
关键词 Three Gorges Project (TGP) trial impoundment reservoir sediment deposition downstream river channel scouring
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Comparative Assessment of the Upstream and Downstream Water Qualities of River Tano in Ghana
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作者 Jackson Adiyiah Helena Aboagye-Larbi Mike Agbesi Acheampong 《Journal of Environmental Science and Engineering(A)》 2013年第5期283-292,共10页
River Tano, located in the Brong Ahafo region of Ghana, has a number of socio-ecological functions. Anthropogenic activities such as farming, washing, and discharge of industrial effluents into the river pose serious ... River Tano, located in the Brong Ahafo region of Ghana, has a number of socio-ecological functions. Anthropogenic activities such as farming, washing, and discharge of industrial effluents into the river pose serious threat to human health. In view of this, water quality campaign was carried out for a period of 12 months by taking samples from the source and the downstream end of the river and analysing for some physico-chemical parameters. The results showed that most of the physico-chemical parameters such as pH, fluoride, nitrite, manganese and temperature were not within the regulatory safe limit. Although the levels of total alkalinity, total iron, ammonia and phosphate kept fluctuating along the course of the river, the difference were not statistically significant apart from fluoride and phosphate which showed significant difference between the upstream and downstream levels. This may be attributed to anthropogenic activities such as farming and washing in the river which implies that human activities have impacted slightly on the water quality. It is recommended that the relevant stakeholders should come together to enforce the environmental laws regarding protection of water bodies and do continuous monitoring for early detection of any change in quality of the River Tano. 展开更多
关键词 PHYSICO-CHEMICAL water resources water quality River Tano UPSTREAM downstream.
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Experimental Investigation on the Shape and Depth of Local Scour Hole Downstream of the Release Structure
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作者 Vouchleang Hong Genguang Zhang +1 位作者 Xinqiang Wang Anbin Li 《World Journal of Engineering and Technology》 2020年第1期104-120,共17页
Local scour downstream of the release structure is a critical problem to the safe and stable operation of water resources and hydropower engineering. In order to investigate the shape and depth of the scour hole under... Local scour downstream of the release structure is a critical problem to the safe and stable operation of water resources and hydropower engineering. In order to investigate the shape and depth of the scour hole under the equilibrium state of erosion and deposition downstream of an apron, a group of 16 experiments from the hydraulic similarity model test of Dangka Hydropower Station?was conducted with the non-cohesive sediment of different median particle sizes under different flow rates in this study. The control variable method was?to?study the influence of the flow rate and sediment size on the shape of the scour hole to define the number of experiment times of each test group. The results showed that the plane shape of the scour hole was irregular ellipse or semi-ellipse. The depth and size of the scour hole increased with the increase of the flow rate, and decreased with the increase of the sediment size;?the downstream longitudinal slope ratio of the scour hole increased with the increase of the sediment size. The coefficients of the upstream and downstream slope ratio of the local scour hole were 1/2 to 1/6 and about 1/10, respectively. 展开更多
关键词 LOCAL SCOUR downstream Noncohesive SEDIMENT Bed SEDIMENT Size FLOW Rate FLOW Pattern Dangka HYDROPOWER Station
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Study the Effectiveness of ISO 27001 to Mitigate the Cyber Security Threats in the Egyptian Downstream Oil and Gas Industry
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作者 Mohamed Shohoud 《Journal of Information Security》 2023年第2期152-180,共29页
As Egyptian oil and gas downstream information technology has grown digitally over the past decade, security breaches against these digitally connected systems have also increased. These cyber security threats could h... As Egyptian oil and gas downstream information technology has grown digitally over the past decade, security breaches against these digitally connected systems have also increased. These cyber security threats could have devastating effects on the operations and reputation of these companies. Preventing such cyberattacks is crucial. Especially, with the significance of the Egyptian oil and gas downstream sector to the local economy and the fact that many of these connected systems are sometimes managed remotely. This paper examines the value of the ISO 27001 standard in mitigating the effect of cyber threat and seeks to inspire decision-makers to the importance of the proactive measures to strengthen their organization’s cybersecurity posture and protect information critical assets. The study stresses the importance of improving the local educational system to bridge the gap between supply and demand for cybersecurity specialists by implementing a structured approach that emphasizes behavior modification to get a high return on investment in cybersecurity awareness. 展开更多
关键词 downstream Cyberattack Cyber Security Mitigate Decision-Makers Proac-tive Measure Critical Assets Behavior Modification
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Vegetation Influence Investigation of GangnanHuangbizhuang Reservoir Downstream River and Recovery Strategies
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作者 张茹春 郑振华 +1 位作者 崔建军 张韬 《Agricultural Science & Technology》 CAS 2015年第11期2552-2554,共3页
The research selected three typical areas for plant investigation, including upper reaches of Gangnan Reservoir, the area between Gangnan and downstream of Huangbizhuang Reservoir, and Huangbizhuang Reservoir. The res... The research selected three typical areas for plant investigation, including upper reaches of Gangnan Reservoir, the area between Gangnan and downstream of Huangbizhuang Reservoir, and Huangbizhuang Reservoir. The results showed that affected by water, plant species, species diversity and species richness were all decreasing in varying degrees as the distance with watercourse upper reaches was increasing, but the ratio of Anthropochory plants was growing. The research finally proposed countermeasures, including increasing wetland area, constructing forests and artificial water landscape of Hutuo River and reinforcing watercourse compre- hensive management. 展开更多
关键词 the reservoir downstream river VEGETATION Gangnan-Huangbizhuangreservoir Vegetation restoration
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GEOCHEMICALLY CONTROLLED CALCITE PRECIPITATION BY CO_2-OUTGASSING: FIELD MEASUREMENTS OF PRECIPITATION RATES IN COMPARISON TO THEORETICAL PREDICTIONS 被引量:21
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作者 W.Dreybrodt D.Buhmann +1 位作者 J.Michaelis E.Usdowski 《中国岩溶》 CAS CSCD 北大核心 1992年第S1期9-24,共16页
A small spring fed stream precipitates calcite by outgassing of CO<sub>2</sub> due to chemically controlled inorganic processes. The chemical composition of the water was measured along 9 stations downstre... A small spring fed stream precipitates calcite by outgassing of CO<sub>2</sub> due to chemically controlled inorganic processes. The chemical composition of the water was measured along 9 stations downstream with respect to Ca<sup>2+</sup>, Mg<sup>2+</sup>, Na<sup>+</sup>,K<sup>+</sup>, Cl<sup>-</sup>, carbonate alkalinlty, and SO<sub>4</sub><sup>2-</sup>. Temperature and pH were measured in situ. Small rectangular shaped tablets of limestone from the area were immersed into the stream for short periods and water analyses were carried out at the same time. From weight increase of the tablets, precipitation rates 展开更多
关键词 CARBONATE LIMESTONE downstream chemically dissolution immersed TABLETS inorganic shaped STRATA
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Performance of the Wind Farm Parameterization Scheme Coupled with the Weather Research and Forecasting Model under Multiple Resolution Regimes for Simulating an Onshore Wind Farm 被引量:5
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作者 Rajabu J.MANGARA Zhenhai GUO Shuanglin LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第2期119-132,共14页
We use the Wind Farm Parameterization(WFP) scheme coupled with the Weather Research and Forecasting model under multiple resolution regimes to simulate turbulent wake dynamics generated by a real onshore wind farm and... We use the Wind Farm Parameterization(WFP) scheme coupled with the Weather Research and Forecasting model under multiple resolution regimes to simulate turbulent wake dynamics generated by a real onshore wind farm and their influence at the local meteorological scale. The model outputs are compared with earlier modeling and observation studies. It is found that higher vertical and horizontal resolutions have great impacts on the simulated wake flow dynamics. The corresponding wind speed deficit and turbulent kinetic energy results match well with previous studies. In addition, the effect of horizontal resolution on near-surface meteorology is significantly higher than that of vertical resolution. The wake flow field extends from the start of the wind farm to downstream within 10 km, where the wind speed deficit may exceed 4%. For a height of 150 m or at a distance of about 25 km downstream, the wind speed deficit is around 2%. This indicates that, at a distance of more than 25 km downstream, the impact of the wind turbines can be ignored. Analysis of near-surface meteorology indicates a night and early morning warming near the surface, and increase in near-surface water vapor mixing ratio with decreasing surface sensible and latent heat fluxes. During daytime, a slight cooling near the surface and decrease in the near-surface water vapor mixing ratio with increasing surface sensible and latent heat fluxes is noticed over the wind farm area. 展开更多
关键词 UPSTREAM downstream WIND FARM impact WIND FARM PARAMETERIZATION scheme WAKE flow dynamics
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Nonplanar post-buckling analysis of simply supported pipes conveying fluid with an axially sliding downstream end 被引量:6
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作者 Tianli JIANG Huliang DAI +1 位作者 Kun ZHOU Lin WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2020年第1期15-32,共18页
In this study,the nonplanar post-buckling behavior of a simply supported fluid-conveying pipe with an axially sliding downstream end is investigated within the framework of a three-dimensional(3 D)theoretical model.Th... In this study,the nonplanar post-buckling behavior of a simply supported fluid-conveying pipe with an axially sliding downstream end is investigated within the framework of a three-dimensional(3 D)theoretical model.The complete nonlinear governing equations are discretized via Galerkin’s method and then numerically solved by the use of a fourth-order Runge-Kutta integration algorithm.Different initial conditions are chosen for calculations to show the nonplanar buckling characteristics of the pipe in two perpendicular lateral directions.A detailed parametric analysis is performed in order to study the influence of several key system parameters such as the mass ratio,the flow velocity,and the gravity parameter on the post-buckling behavior of the pipe.Typical results are presented in the form of bifurcation diagrams when the flow velocity is selected as the variable parameter.It is found that the pipe will stay at its original straight equilibrium position until the critical flow velocity is reached.Just beyond the critical flow velocity,the pipe would lose stability by static divergence via a pitchfork bifurcation,and two possible nonzero equilibrium positions are generated.It is shown that the buckling and post-buckling behaviors of the pipe cannot be influenced by the mass ratio parameter.Unlike a pipe with two immovable ends,however,the pinned-pinned pipe with an axially sliding downstream end shows some different features regarding post-buckling behaviors.The most important feature is that the buckling amplitude of the pipe with an axially sliding downstream end would increase first and then decrease with the increase in the flow velocity.In addition,the buckled shapes of the pipe varying with the flow velocity are displayed in order to further show the new post-buckling features of the pipe with an axially sliding downstream end. 展开更多
关键词 fluid-conveying pipe axially sliding downstream end NONPLANAR postbuckling behavior
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Monitoring and Analysis on Impact of Gezhouba Hydroproject on Downstream River Course 被引量:5
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作者 TANG Cong-shengSenior Engineer, Jingjiang Hydrologic and Water Resources Survey Bureau, Changjiang Water Resources Commission, Jingzhou 434002, China SONG Shi-jieEngineer, Jingjiang Hydrologic and Water Resources Survey Bureau, Changjiang Water Resources Commission, Jingzhou 434002, China WANG Wei-guoSenior Engineer, Jingjiang Hydrologic and Water Resources Survey Bureau, Changjiang Water Resources Commission, Jingzhou 434002, China HU Chun-pingSenior Engineer, Jingjiang Hydrologic and Water Resources Survey Bureau, Changjiang Water Resources Commission, Jingzhou 434002, China 《人民长江》 北大核心 2002年第S1期46-49,共4页
Gezhouba hydroproject was impounded and put into operation in 1981. In order to analyse the impact on the downstream river course, Jingjiang Hydrologic and Water Resources Survey Bureau of Changjiang Water Resources C... Gezhouba hydroproject was impounded and put into operation in 1981. In order to analyse the impact on the downstream river course, Jingjiang Hydrologic and Water Resources Survey Bureau of Changjiang Water Resources Commission has conducted prototype observation on the Yichang-Chenglingji river stretch. On basis of the observed data, the change in river regime and scour-sedimentation evolution and water surface profile below the dam are analysed systematically. The results show that the scouring of downstream river course mainly stretches from Yichang to Ouchikou, mainly occurring in 1980~1987; the scourring mainly takes place in the river channel and the water surface profile drops significantly in dry season,but not quite in high flood season. 展开更多
关键词 downstream RIVER channel monitoring and analysis RIVER REGIME evolution scour-sediment computation variation of water surface Gezhouba hydroproject
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Key Technologies of the Hydraulic Structures of the Three Gorges Project 被引量:6
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作者 马洪琪 迟福东 《Engineering》 SCIE EI 2016年第3期340-349,共10页
To date,the Three Gorges Project is the largest hydro junction in the world.It is the key project for the integrated water resource management and development of the Changjiang River.The technology of the project,with... To date,the Three Gorges Project is the largest hydro junction in the world.It is the key project for the integrated water resource management and development of the Changjiang River.The technology of the project,with its huge scale and comprehensive benefits,is extremely complicated,and the design difficulty is greater than that of any other hydro project in the world.A series of new design theories and methods have been proposed and applied in the design and research process.Many key technological problems regarding hydraulic structures have been overcome,such as a gravity dam with multi-layer large discharge orifices,a hydropower station of giant generating units,and a giant continual multi-step ship lock with a high water head. 展开更多
关键词 Three Gorges Project Large orifice gravity dam Penstock on dam downstream surface Tailrace tunnel with sloping ceiling Stable archFully lined ship lock
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THE SIMULATION OF LIQUID DISTRIBUTION BASED ON MARKOV PROCESS 被引量:2
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作者 张泽廷 余国琮 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1990年第1期112-121,共10页
The Markov process with discrete state and time is used to simulate the distribution of liquid flow in apacked column.The theoretical prediction agrees well with the experimental data.
关键词 Probability RADIAL downstream STEPS illustrated DOWNWARD designated flowing RADIUS UNIFORMLY
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Raman spectroscopy as process analytical tool in downstream processing of biotechnology 被引量:2
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作者 Yu Kiat Lin Hui Yi Leong +2 位作者 Tau Chuan Ling Dong-Qiang Lin Shan-Jing Yao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第2期204-211,共8页
Downstream processing or product recovery plays a vital role in the development of bioprocesses.To improve the bioprocess efficiency,some unconventional methods are much required.The continuous manufacturing in downst... Downstream processing or product recovery plays a vital role in the development of bioprocesses.To improve the bioprocess efficiency,some unconventional methods are much required.The continuous manufacturing in downstream processing makes the Process Analytical Technologies(PATs)as an important tool.Monitoring and controlling bioprocess are an essential factor for the principles of PAT and quality by design.Spectroscopic methods can apply to monitor multiple analytes in real-time with less sample processing with significant advancements.Raman spectroscopy is an extensively used technique as an analytical and research tool owing to its modest process form,non-destructive,non-invasive optical molecular spectroscopic imaging with computer-based analysis.Generally,its application is essential for the analysis and characterization of biological samples,and it is easy to operate with minimal sample.The innovation on various types of enhanced Raman spectroscopy was designed to enhance the Raman analytical technique.Raman spectroscopy could couple with chemometrics to provide reliable alternative analysis method of downstream process analysis.Thus,this review aims to provide useful insight on the application of Raman spectroscopy for PAT in downstream processing of biotechnology and Raman data analysis in biological fields. 展开更多
关键词 Raman spectroscopy Process analytical technology downstream bioprocessing BIOTECHNOLOGY
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From basic researches to new achievements in therapeutic strategies of KRAS-driven cancers 被引量:2
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作者 Mahsa Saliani Razieh Jalal Mohammad Reza Ahmadian 《Cancer Biology & Medicine》 SCIE CAS CSCD 2019年第3期435-461,共27页
Among the numerous oncogenes involved in human cancers, KRAS represents the most studied and best characterized cancerrelated genes.Several therapeutic strategies targeting oncogenic KRAS(KRASonc) signaling pathways h... Among the numerous oncogenes involved in human cancers, KRAS represents the most studied and best characterized cancerrelated genes.Several therapeutic strategies targeting oncogenic KRAS(KRASonc) signaling pathways have been suggested,including the inhibition of synthetic lethal interactions, direct inhibition of KRASonc itself, blockade of downstream KRASonc effectors, prevention of post-translational KRASonc modifications, inhibition of the induced stem cell-like program, targeting of metabolic peculiarities, stimulation of the immune system, inhibition of inflammation, blockade of upstream signaling pathways,targeted RNA replacement, and oncogene-induced senescence.Despite intensive and continuous efforts, KRASonc remains an elusive target for cancer therapy.To highlight the progress to date, this review covers a collection of studies on therapeutic strategies for KRAS published from 1995 to date.An overview of the path of progress from earlier to more recent insights highlight novel opportunities for clinical development towards KRASonc-signaling targeted therapeutics. 展开更多
关键词 Direct inhibition downstream EFFECTORS oncogenic KRAS drug target sites small GTPASES signal TRANSDUCTION targeting synthetic lethal interactions therapeutic strategies
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Influence of Hydrodynamic Conditions and Water Chemistry on the Formation of Tufa in Huanglong, Sichuan 被引量:1
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作者 W.Dreybrodt U.Svensson 《中国岩溶》 CAS CSCD 北大核心 1992年第S1期87-101,共15页
In order to study the origin of the local tufa deposits hydrochemical and hydrodynamic investigations have been carried out at a mainly spring-fed stream during two field campaigns, Preliminary results, supported by ... In order to study the origin of the local tufa deposits hydrochemical and hydrodynamic investigations have been carried out at a mainly spring-fed stream during two field campaigns, Preliminary results, supported by δ13C data. suggest that calcite precipitation is entirely controlled by inorganic processes. The evolution of hydrochemistry with respect to major ions was measured at diffe- 展开更多
关键词 entirely HYDRODYNAMIC inorganic carbonate PLANNED shaped tempera cooperation downstream ISOTOPE
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N-myc downstream regulated gene 1 inhibition of tumor progression in Caco2 cells 被引量:2
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作者 Yi-Xiao He Hong Shen +5 位作者 Yu-Zhu Ji Hai-Rong Hua Yu Zhu Xiang-Fei Zeng Fang Wang Kai-Xin Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2022年第12期2313-2328,共16页
BACKGROUND Invasion and migration are the irreversible stages of colorectal cancer(CRC).The key is to find a sensitive,reliable molecular marker that can predict the migration of CRC at an early stage.N-myc downstream... BACKGROUND Invasion and migration are the irreversible stages of colorectal cancer(CRC).The key is to find a sensitive,reliable molecular marker that can predict the migration of CRC at an early stage.N-myc downstream regulated gene 1(NDRG1)is a multifunctional gene that has been tentatively reported to have a strong relationship with tumor invasion and migration,however the current molecular role of NDRG1 in CRC remains unknown.AIM To explore the role of NDRG1 in the development of CRC.METHODS NDRG1 stably over-expressed Caco2 cell line was established by lentiviral infection and NDRG1 knock-out Caco2 cell line was established by CRISPR/Cas9.Furthermore,the mRNA and protein levels of NDRG1 in Caco2 cells after NDRG1 over-expression and knockout were detected by real-time polymerase chain reaction and western blot.The cell proliferation rate was measured by the cell counting kit-8 method;cell cycle and apoptosis were detected by flow cytometry;invasion and migration ability were detected by the 24-transwell method.RESULTS NDRG1 over-expression inhibited Caco2 proliferation and the cell cycle could be arrested at the G1/S phase when NDRG1 was over-expressed,while the number of cells in the G2 phase was significantly increased when NDRG1 was knocked out.This suggests that NDRG1 inhibited the proliferation of Caco2 cells by arresting the cell cycle in the G1/S phase.Our data also demonstrated that NDRG1 promotes early cell apoptosis.Invasion and migration of cells were extensively inhibited when NDRG1 was over-expressed.CONCLUSION NDRG1 inhibits tumor progression in Caco2 cells which may represent a potential novel therapeutic strategy for the treatment of CRC. 展开更多
关键词 N-myc downstream regulated gene 1 Caco2 Colorectal cancer Tumor progression CRISPR/Cas9 Lentivirus infection
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