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EVALUATION OF WATER AND SEDIMENT QUALITIES AT RIVER MOUTHS IN THE HAIHE RIVER SYSTEM
Water and sediment qualities are studied by analyzing samples taking from the mouths of the Haihe, Duliujian, New Ziya and Beipai rivers in the Haihe river basin in north China in 2005 and 2001, in order to find the changes of water and sediment pollutions. The concentrations of heavy metals, arsenic, total nitrogen (TN) and total phosphorus (TP) are analyzed and results have been compared for the two times. The in-situ measurement for Dissolved Oxygen (DO) and Sediment Oxygen Demand (SOD) rates were carried at the Haihe and Duliujian river mouths in 2006. The results show that the waters of the 4 river mouths are still seriously polluted, though much improved in the case of the Haihe and Duliujian rivers. The main pollutants are TP and TN in the New Ziya and Beipai rivers and mercury (Hg) at all 4 river mouths. Compared with those in 2001, the concentrations of almost all metals and arsenic in the 4 river mouths have decreased. Water quality at Haihe and Duliujian shows an improving trend, while the water quality at Beipai is similar to that of 2001. In contrast, water at the New Ziya river mouth is more severely polluted. The sediments in the 4 river mouths are not seriously polluted by heavy metals but are polluted by nitrogen and phosphorus. Most of the pollutant contents in the sediments show little change between 2001 and 2005. The in-situ DO and SOD measurement shows that the waters at the Haihe river mouth is in the state of oxygen depletion, and SOD is important consumer of DO at the river mouths. The overall analysis shows that increasing water pollution and eutrophication in waters far from cities are ongoing causes of concern....
2020-07-08 21:52:19浏览：21
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Assessment of Cu, Pb and Hg Contamination in Bottom Sediments Of Surface Water in XuZhou
Pollution of heavy metals Cu,Pb and Hg is assessed using geo-accumulation index in this paper. The result shows that the bottom sediments of surface water in Xuzhou is polluted by these heavy metals to deferent degrees, of which the Jinma River is the most serious, and then the Kuihe River, the abandoned Yellow River, and the Jinghang Canal. The Yunlong Lake has also been polluted by Hg. The three kinds of heavy metals in the order of concentration is Hg＞Cu＞Pb. The pollution degree and the type of element is closely related with industrial structure in Xuzhou....
2020-07-08 21:52:19浏览：57
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Water quality characteristics along the course of the Huangpu River (China)
Huangpu River is about 114.5 km from upriver Dianfeng to downriver Wusong, near the estuary of the Yangtze River. It plays a key role in supplying water for production, life, shipment and irrigation. With the industrial development, the pollution of the Huangpu River has become serious recently. The biological oxygen demand (BOD), total nitrogen (TN), total phosphorus (TP), oil, phenol and suspended solids (SS) were lower in the upstream sites than in the downstream sites, indicating pollutants being input along its course.Water quality was the worst in the Yangpu site, near the center of Shanghai City. Dissolved oxygen (DO) content was less than 2mg/L in the site of Yangpu in July. Among relations between thirteen characteristics, relations between BOD, DO, TN, TP, NH4+-N,NO3--N and the count of total bacteria or Escherichia coli were significant and interdependent. Inner relationships between these main characteristics in the Huangpu River were studied. High nutrient concentration led to growth of microorganisms, including E. coli.Degradation of organic matters and respiration of bacteria made oxygen concentration decreased in the water body, and DO was a key factor for nitrification-denitrification process of nitrogen. In the Yangpu site, DO was decreased to less than 3.0 mg/L with BOD higher than 7.5 mg/L in May and July. Low DO concentration will decrease nitrification rate. Nitrification need at higher DO value than other organic substrate oxidation. Consequently, river water contains low NO3--N values with high amounts of TN and NH4+-N there. This will block the self-purification of surface water, by decreasing the rate of nitrification-denitrification transformation process in the water body....
2020-07-08 21:52:19浏览：51
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Modulation of leaf conductance by root to shoot signaling under water stress in Arabidopsis
Signal communication between root and shoot plays a crucial role in plant resistance to water stress. While many studies on root to shoot signals have been carried out in many plant species, no information is available for the model plant, Arabidopsis, whose adoption has great significance for further probing the molecular aspects of long distance stress signals. Here, we introduced the establishment of techniques for investigations of root to shoot signals in Arabidopsis. Stomatal movements in relation to root signals were probed by using these techniques. The results show that Arabidopsis is a suitable plant species for partial roots drying (PRD)experiments. In the PRD system, while no significant differences were found in leaf water potential between well-watered and stressed plants, water stress led to a decrease in leaf conductance, which suggests a regulation of stomatal movements by root to shoot signals. While water stress caused a significant increase in the concentration of sap abscisic acid (ABA) of xylem, no increase in xylem sap pH was observed. Moreover, the increase in the ABA content of xylem coincided with the decrease in leaf conductance,which suggests a possible role of ABA in the regulation of stomatal movements. Infrared temperature images showed that leaf temperatures of PRD plant were higher compared with those of well-watered plants, which further indicates that stomatal movements can be modulated by root signals. The confirmation of root to shoot signaling in Arabidopsis has established a basis for further investigation into the molecular mechanisms of the root to shoot signaling under water stress....
2020-07-08 21:52:19浏览：68
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Study on Shanghai Water Management Information Standard and its application
In Shanghai, three trades including water conservancy, water supply and water drainage are managed integratively by Shanghai Water Authority. However, trade division is apparent among them, and information sharing needs to be strengthened.Therefore, lack of information standard is becoming an urgent problem to be solved. According to the strategic objectives of "Golden Water Project" in China and "Digital City" in Shanghai, "Shanghai Water Management Information Standard" is made for normalizing information classifications, codes, terms,GIS symbols and attributed data structures. It not only coincides with national standards,ministerial standards and Shanghai local standards, but also embodies the characteristic of integrated water management in Shanghai. It provides "traffic rule" for resources integrating and information sharing. Some good research ideas such as omni-direction,multi-levels and facing application can be popularized in other provinces and municipalities of China....
2020-07-08 21:52:19浏览：65
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Orthogonal Test About Biogas Upgrading by Pressured Water Scrubbing
Biogas is a kind of regenerable energy which is inexpensive and friendly to the environment, but the potential of biogas is difficult to develop fully in China, for most biogas have badly qualities and the utilization of it is monotonous. The suitable operation term about biogas upgrading by pressurized water scrubbing was researched through the orthogonal test in this study. Two sorts of scrubber packing included the random multidimensional hollow sphere packing and the structured screen packing were also used, and the effects of experiment factors included packing, water temperature, gas flow speed, water flow speed and washing pressure were studied. The results showed that better effect was got when the screen structured packing was used; all the five test factors affected the processing significantly in the arrange as before and had better and better significant effects....
2020-07-08 21:52:19浏览：41
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A New Water Saving Device of Swirling Flow for Cooling Towers
This paper is concerned with water saving for water-loop cooling tower system in power plants.A newly developed water saving device of swirling flow is prevented The key point is that the new water saving device makes the steam swirl up along the device wall rather than engender laminar flow in a corrugated plate.The corrugated plate device can save approximately 10 percent of the total lost water.In contrast to the scale model of corrugated plate water saving device,experimental analyses have demonstrated that the new water saving device of swirlingflow is more efficient,with a capacity of saving more than 20percent of water....
2020-07-08 21:52:19浏览：61
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Discussion about the standard system on urban domestic water saving technology in China
Standard is the technical foundation of national economic and social development, and it is the basic rule of establishing social regulation.Researching and constituting the standard system of urban domestic water saving technology is to offer important science basis for revising standard plan and standardize research plan. This paper introduces the present situation of our urban domestic water saving technical standard system, problem and the development direction in the future, as well as project planning of constructing urban domestic water saving technical standard system....
2020-07-08 21:52:19浏览：60
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Effect of Hot Water Treatment on Postharvest Shelf Life and Quality of Broccoli
Broccoli was stored at 0, 10, or 20℃ after immersion in hot water (38 -52℃ ) for 10 or 30min. Yellowing of broccoli was significantly slowed and shelf life significantly increased when broccoli wastreated with hot water at 42 -46℃ and then stored at 10 or 20℃. Heat injury occurred when treatment washigher than 46℃ in some varieties. Broccoli lasted 2 -3 days longer when stored at 10℃ and 1 -2 days longerwhen stored at 20℃ after hot water treatment at 46℃. There was no significant effect of treatment on shelflife after long time storage at 0℃. Weight loss was reduced by hot water treatment and the respiration behav-ior of the broccoli was also changed....
2020-07-08 21:52:19浏览：65
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Soil Water Distribution and Irrigation Uniformity Under Alternative Furrow Irrigation
Field experiments were conducted to investigate the spatial-temporal distribution and the uni-formity of soil water under alternative furrow irrigation in spring maize field in Gansu Province. Resultsshowed that during the crop growing season, alternative drying and wetting furrows could incur crops to en-dure a water stress, thus the adsorptive ability of root system could be enhanced. As there was no zero fluxplane between irrigated furrows and non-irrigated furrows under alternative furrow irrigation, lateral infiltra-tion of water was obviously increased, thus decreasing the deep percolation. Compared with the conventionalirrigation, although the water consumption in alternative furrow irrigation was reduced, the uniformity of soilwater was not obviously affected....
2020-07-08 21:52:19浏览：67
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Residual Stress Improved by Water Jet Peening for A Quenched Gear
In this paper, a running cost is cheap from the thing used for harmless peening treatment to the environment,health which an influence is rare in toward processing material like heat being only water fundamentally, and economical,and the characteristics is hard to get are given. There is some research about the residual stress improvement by water-jet peening during the high-speed water. In this study, a big bubble cloud ceremony water-jet peening which dissolves the problem of the form of the applicable thing by exposing the whole of the applicable thing in the big bubble cloud as the way of dealing with peening efficiently in a short time is proposed by this research. Moreover, the uniform compression residual stress is added around the surface of the processing side, and connected with the remarkable improvement of the fatigue strength of the part. Furthermore, and safety processing is very possible, and it thinks about the thing which has possible high practical use, and writers to get rid of the problems of the way of processing it with peening until now. Water-jet peening was given by this research during high-speed water with big bubble cloud-type water toward tooth gear manufactured by SCr420H3V2 to open the effect of water-jet peening during the high-speed water. A change was measured at the time as the sutra of the residual stress on the surface of the test settlement by the X-ray method, and the validity of this law was verified....
2020-07-08 21:52:19浏览：45
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Comparative experimental investigation of chemical grouting into a fracture with flowing and static
We present a series of experimental tests on chemical grouting into a fracture with flowing and static water, using a transparent fracture grouting experimental device. Variations of seepage pressure and grout propagation were compared in our investigation. The results show that flowing water results in drops of seepage pressure, development of penetration radii in the upstream side and drops of propagation area during the same period, compared with grouting in static water. The propagation area in static water is always round before grouts reach the joint boundaries. However, the propagation shape changes from round to an elliptic shape for grouting into a fracture with flowing water. A theoretical model for the grout penetration radius in a fracture considering flowing velocity was developed and validated by our experimental results. These results are helpful in improving understanding of fracture grouting mechanism and in guiding engineering practices....
2020-07-08 21:52:19浏览：57
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DEVELOPMENT OF TWO-DIMENSIONAL HYDRODYNAMIC AND WATER QUALITY MODEL FOR HUANGPU RIVER
Based on numerical computation model RMA2 and RMA4 with open source code, finite element meshes representing the study domain are created, then the finite element hydrodynamic and water quality model for Huangpu River is developed and calibrated, and the simulation results are analyzed. This developed hydrodynamic and water quality model is used to analyze the influence of discharged wastewater from planning Wastwater Treatment Plant (WWTP) on Huangpu River's water quality....
2020-07-08 21:52:19浏览：47
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A dynamic analysis of water footprint of Jinghe River basin
Water footprint in a region is defined as the volume of water needed for the production of goods and services consumed by the local people. Ecosystem services are a kind of important services, so ecological water use is one necessary component in water footprint. Water footprint is divided into green water footprint and blue water footprint but the former one is often ignored. In this paper water footprint includes blue water needed by agricultural irrigation, industrial and domestic water demand, and green water needed by crops, economic forests, livestock products, forestlands and grasslands. The study calculates the footprint of the Jinghe River basin in 1990,1995, 2000 and 2005 with quarto methods. Results of research show that water footprints reached 164.1 × 108m3, 175.69×108m3 and 178.45×108m3 respectively in 1990, 1995 and 2000 including that of ecological water use, but reached 77.68×108m3, 94.24×108m3, 92.92×108m3 and 111.36×108m3 respectively excluding that of ecological water use. Green water footprint is much more than blue water footprint: thereby, green water plays an important role in economic development and ecological construction. The dynamic change of water footprints stows that blue water use increases rapidly and that the ecological water use is occupied by economic and domestic water use. The change also shows that water use is transferred from primary industry to secondary industry. In primary industry, it is transferred from crops farming to forestry and animal agriculture. The factors impelling the change include development anticipation on economy, government policies, readjustment of the industrial structure, population growth, the raise of urbanization level, and structural change of consumption, low level of water-saving and poor ability of waste water treatment. With blue water use per unit, green water use per unit, blue water use structure and green water use structure, we analyzed the difference of the six ecological function districts of the Jinghe River basin. Future ecological construction may influence on blue water use of District V and District VI at middle and lower reaches. At last some suggestions are given for effective water resource use....
2020-07-08 21:52:19浏览：50
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Study on the changes of water cycle and its impacts in the source region of the Yellow River
The water cycle in the source region of the Yellow River underwent great changes in the 1990s. The major features of the changes are as follows: the gauged runoff declined significantly while the precipitation increased slightly, and the runoff process was more concentrated on the flood season. Water balance analyses indicate that the pondage was kept in the status of negative equilibrium, causing eco-environmental problems. The runoff decrement is due to evaporation increment in this region. Studies show that the runoff process in this region is closely related to that of the other hydrological stations in the upper reaches. When the runoff declines in the source regions, the amount of water also declines in the whole upper reaches of the Yellow River, affecting the balance between water demand and supply. Meanwhile changes will take place in the water cycle of the river course system when the eco-environment deteriorates. The trend of water cycle change in the source region is that the runoff will keep declining with the increment of evaporation caused by temperature rise in the northwest of China in the 21st century. But the hydraulic engineering in the source region will help to mitigate the deterioration of local eco-environment system, though the impacts to the lower reaches of this project may not be the case....
2020-07-08 21:52:19浏览：61
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