Influence of Water Exchange in Tide and Wave for Large Harbor with One Entrance

2013 ◽  
Vol 405-408 ◽  
pp. 1411-1414
Author(s):  
Jie He ◽  
Wen Jie Xin
Keyword(s):  
Point Source ◽  
Water Flow ◽  
Tidal Current ◽  
Water Exchange ◽  
Water Environment ◽  
Zhejiang Province ◽  
Polluted Water ◽  
Influence Of Water ◽  
The Waves ◽  
Exchange Flux

For the large coastal harbor with one entrance attacked badly from the waves and sands from the sea, it is advantaged to break waves and produce sands, but not advantaged for the water exchange flux, especially when a point source appearing inside the harbor, the polluted water is difficult to flow into the sea in time and be diluted by the water from outside. The water flow in estuary presents the character of to-and-fro flow, and the polluted source will flow into harbor with the flood tide and pollute the harbor secondly, although it has been outside the harbor at least with the ebb tide. For the harbor with one entrance against waves, the polluted source will be more difficult to be transported to the outside when waves coming, and the water environment capacitance will decline rapidly for the polluted water not to be absorbed. It is Taizhou Wenling harbor for example in Zhejiang province, and the movement of water particle is simulated in tidal current and wave to describe the movement of the point source transported not diffused. The rusults show that the capacity of water exchange for the large harbor wih one entrance will be declined in both tidal current and wave.

scholarly journals Kinetics and isotherm modeling of Pb(II) and Cd(II) sequestration from polluted water onto tropical ultisol obtained from Enugu Nigeria

2021 ◽  
Vol 11 (4) ◽  
Author(s):  
Theresa C. Umeh ◽  
John K. Nduka ◽  
Kovo G. Akpomie
Keyword(s):  
Metal Ions ◽  
Low Cost ◽  
Water Environment ◽  
Standard Technique ◽  
Soil Surface ◽  
Cost Effective ◽  
Polluted Water ◽  
Batch Adsorption ◽  
Lead And Cadmium ◽  
Pseudo Second Order

AbstractDeterioration in soil–water environment severely contributed by heavy metal bioavailability and mobility on soil surface and sub-surface due to irrational increase in wastewater discharge and agrochemical activities. Therefore, the feasibility of adsorption characteristics of the soil is paramount in curbing the problem of micropollutant contamination in the farming vicinity. Soil from a farming site in a populated area in Enugu, Nigeria was collected and tested to measure the lead and cadmium contents using atomic absorption spectrophotometer (AAS). The adsorption potency of the ultisol soil was estimated for identifiable physicochemical properties by standard technique. The mean activity concentration of Pb2+ and Cd2+ was 15.68 mg/kg and 3.01 mg/kg. The pH, temperature, metal concentration and contact time adsorptive effect on the Pb2+ and Cd2+ uptake was evaluated by batch adsorption technique. The Langmuir, Freundlich and Temkin models were fitted into equilibrium adsorption data and the calculated results depict a better and satisfactory correlation for Langmuir with higher linear regression coefficients (Pb2+, 0.935 and Cd2+, 0.971). On the basis of sorption capacity mechanism of the soil, pseudo-second-order model best described the kinetics of both metal ions retention process. The results of the present study indicated that the soil being a low cost-effective adsorbent can be utilized to minimize the environmental risk impact of these metal ions.

Study on Water Quality Improvement of Streams in Baoan District, Shenzhen City, China

2011 ◽  
Vol 347-353 ◽  
pp. 1902-1905
Author(s):  
Hua Li You
Keyword(s):  
Waste Water ◽  
Mathematical Model ◽  
Water Quality ◽  
Fresh Water ◽  
Water Discharge ◽  
Water Environment ◽  
Oxygen Demand ◽  
Polluted Water ◽  
Integrated Analysis ◽  
Shenzhen City

Water is the basis of natural resources and strategic economic resources.Deteriorated water environment of streams in Shenzhen city could have a great impact on ecological safety, people's health,and economic development.Based on the data of field observation and Remote sensing (RS) image,integrated analysis of the water degradation causes,and the changes of biochemical oxygen demand in five days(BOD5）concentration by mathematical model were carried out,which is on basis of percentage of waste water disposal,fresh water transformation,and harbor excavation, respectively.The results show that degradation causes of water quality were resulted from waste water discharge, harbor construction,and ecological environment damage, which could lead to slowly water exchange. Accordingly,the pollution can be easily to store in the bay,which result in water quality changes.The most important improved countermeasure is the control of waste water, which could be had a great effectiveness to decrease pollution.In addition, fresh water must be supplied after polluted water was cut off,which can be better improvement for water quality.This would be extreme improvement for hydrological dynamics due to 15m harbor excavation,which can significantly reduce BOD5 concentration.The innovation points of this paper is to mathematical model,which is based on the basis of qualitative analysis.

scholarly journals Molecular epidemiologic characteristics of hemagglutinin from five waves of avian influenza A (H7N9) virus infection, from 2013 to 2017, in Zhejiang Province, China

2021 ◽  
Author(s):  
Yi Sun ◽  
Haiyan Mao ◽  
Xiuyu Lou ◽  
Xinying Wang ◽  
Yin Chen ◽  
...  
Keyword(s):  
Amino Acid ◽  
Influenza A ◽  
Zhejiang Province ◽  
Personal Genome ◽  
Nucleotide Polymorphisms ◽  
Single Nucleotide ◽  
Amino Acid Mutations ◽  
Influenza Outbreaks ◽  
Epidemiological Characteristics ◽  
The Waves

AbstractThere have been five waves of influenza A (H7N9) epidemics in Zhejiang Province between 2013 and 2017. Although the epidemiological characteristics of the five waves have been reported, the molecular genetics aspects, including the phylogeny, evolution, and mutation of hemagglutinin (HA), have not been systematically investigated. A total of 154 H7N9 samples from Zhejiang Province were collected between 2013 and 2017 and sequenced using an Ion Torrent Personal Genome Machine. The starting dates of the waves were 16 March 2013, 1 July 2013, 1 July 2014, 1 July 2015, and 1 July 2016. Single-nucleotide polymorphisms (SNPs) and amino acid mutations were counted after the HA sequences were aligned. The evolution of H7N9 matched the temporal order of the five waves, among which wave 3 played an important role. The 55 SNPs and 14 amino acid mutations with high frequency identified among the five waves revealed the dynamic occurrence of mutation in the process of viral dissemination. Wave 3 contributed greatly to the subsequent epidemic of waves 4 and 5 of H7N9. Compared with wave 1, wave 5 was characterized by more mutations, including A143V and R148K, two mutations that have been reported to weaken the immune response. In addition, some amino acid mutations were observed in wave 5 that led to more lineages. It is necessary to strengthen the surveillance of subsequent H7N9 influenza outbreaks.

The Influence of water flow rate on Pumping Rate in Mytilus Edulis using a Refined Direct Measurement Apparatus

1976 ◽  
Vol 56 (2) ◽  
pp. 311-319 ◽  
Author(s):  
D. I. Hildreth
Keyword(s):  
Water Flow ◽  
Direct Measurement ◽  
Water Flow Rate ◽  
Mantle Cavity ◽  
Water Current ◽  
Ciliary Activity ◽  
Pumping Rate ◽  
Influence Of Water ◽  
Food Particles ◽  
Flow Through

INTRODUCTIONWork on pumping and filtration rates of bivalve molluscs was initially concerned with the physiological concept of pumping water through the mantle cavity. Comprehensive reviews are given by Winter (1970) and Ali (1971). The methods are of two kinds; direct, in which the flow of exhaled water itself is measured, and indirect, in which the rate of clearance of food particles is used to calculate water flow through the gills.There is a disadvantage in the indirect method when used to calculate volumes of water pumped because it involves the assumption that a fixed percentage (often 100% with large particles) of the particulate matter passing through the gill system is retained. Pumping rate is thus estimated as a function of the particle collecting properties of the latero-frontal cirri, whereas the water current is produced by the lateral cilia. Although the structure of the latero-frontal cirri is now well documented (Moore, 1971), their efficiency in particle retention can alter under certain conditions (Dral, 1967). There is need, therefore, for direct measurement of the quantity of water pumped. Recent advances in the understanding of branchial innervation and the control of lateral ciliary activity also reinforce this point (Aiello, 1960, 1962, 1970; Paparo, 1972, 1973).The constant level chamber for direct measurement of pumping rate was devised by Galtsoff (1926), to ensure that separation of the exhalant water current from the bivalve was not interfered with by pressure differences produced by the process of separation. The apparatus has been used in various forms by Galtsoff (1926, 1928, 1946), Nelson (1935, 1936), Collier & Ray (1948), Loosanoff & Engle (1947), Loosanoff & Nomejko (1946) and more recently by Drinnan (1964) and Davids (1964).

Influence of water flow on pipe inspection

2005 ◽  
Author(s):  
Rais Ahmad ◽  
Sourav Banerjee ◽  
Tribikram Kundu
Keyword(s):  
Water Flow ◽  
Pipe Inspection ◽  
Influence Of Water

Study of water exchange in Kerch strait using NEMO model of Black Sea

2021 ◽  
Author(s):  
Roman Sedakov ◽  
Barnier Bernard ◽  
Jean-Marc Molines ◽  
Anastasiya Mershavka
Keyword(s):  
Water Flow ◽  
Black Sea ◽  
Water Exchange ◽  
Discharge Rate ◽  
The Black Sea ◽  
External Forcing ◽  
Sea Of Azov ◽  
The Sea Of Azov ◽  
The North ◽  
Kerch Strait

<p>The Sea of Azov is a small, shallow, and freshened sea that receives a large freshwater discharge. Under certain external forcing conditions brackish water from the Sea of Azov flow into the north-eastern part of the Black Sea through the narrow Kerch Strait and form a surface-advected buoyant plume. Water flow in the Kerch Strait also regularly occurs in the opposite direction, which results in the spreading of an advected plume of saline and dense water from the Black Sea into the Sea of Azov. Using a regional Black Sea Azov Sea model based on NEMO we study physical mechanisms that govern water exchange through the Kerch Strait and analyze the dependence of its direction and intensity on external forcing conditions. We show that water exchange in the Kerch Strait is governed by a wind-induced barotropic pressure gradient. Water flow through the shallow and narrow Kerch Strait is a one-way process for the majority of the time. Outflow from the Sea of Azov to the Black Sea is induced by moderate and strong northerly winds, while flow into the Sea of Azov from the Black Sea is induced by southerly winds. The direction and intensity of water exchange have wind-governed synoptic and seasonal variability, and they do not depend on the variability of river discharge rate to the Sea of Azov on an intraannual timescale.</p>

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