Study on Relationship between Groundwater Conductivity and Chemical Characteristics in Seawater Intrusion Area around Laizhou Bay

Based on the monitoring data in the coastal area of Laizhou bay, the paper presents the correlation between groundwater conductivity and chemical characteristics.The results showed that,compared with titration method,application of Diagometer has the advantages of high accuracy,fast speed and simple operation.When the seawater intrusion has not yet occurred or relatively weak,the effect of the application of diagometer is not very obvious.Only when seawater intrusion occurs serious,application of Diagometer can reflect the changes of mineralization degree and chloride ion concentration of groundwater accurately.

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Seawater intrusion vulnerability evaluation and prediction: a case study of Qeshm Island, Iran

Journal of Water and Climate Change ◽

10.2166/wcc.2020.220 ◽

2020 ◽

Cited By ~ 1

Author(s):

Amin Zeynolabedin ◽

Reza Ghiassi ◽

Moharram Dolatshahi Pirooz

Keyword(s):

Seawater Intrusion ◽

Moving Average ◽

Arima Model ◽

Chloride Ion ◽

Absolute Error ◽

Ion Concentration ◽

Qeshm Island ◽

Autoregressive Integrated Moving Average ◽

Dangerous Condition

Abstract Seawater intrusion is one of the most serious issues to threaten coastal aquifers. Tourian aquifer, which is selected as the case study, is located in Qeshm Island, Persian Gulf. In this study, first the vulnerability of the region to seawater intrusion is assessed using chloride ion concentration value, then by using the autoregressive integrated moving average (ARIMA) model, the vulnerability of the region is predicted for 14 wells in 2018. The results show that the Tourian aquifer experiences moderate vulnerability and the area affected by seawater intrusion is wide and is in danger of expanding. It is also found that 0.95 km2 of the region is in a state of high vulnerability with Cl concentration being in a dangerous condition. The prediction model shows that ARIMA (2,1,1) is the best model with mean absolute error of 13.3 mg/L and Nash–Sutcliffe value of 0.81. For fitted and predicted data, mean square error is evaluated as 235.3 and 264.3, respectively. The prediction results show that vulnerability is increasing through the years.

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Chemical characteristics of groundwater and source identification in a coastal city

PLoS ONE ◽

10.1371/journal.pone.0256360 ◽

2021 ◽

Vol 16 (8) ◽

pp. e0256360

Author(s):

Qun Miao ◽

Xuefei Li ◽

Youqin Xu ◽

Chao Liu ◽

Ruikang Xie ◽

...

Keyword(s):

Groundwater Quality ◽

Coastal Area ◽

Concentration Distribution ◽

Ion Concentration ◽

Chemical Characteristics ◽

Hydrochemical Characteristics ◽

Coastal City ◽

Groundwater Sampling ◽

Anions And Cations ◽

Coefficient Method

A coastal city is studied in this paper. Based on 42 groundwater sampling points, a Piper diagram, the Shukarev classification, the Pearson correlation analysis, Gibbs plots and the ion proportional coefficient method are used to analyze the chemical characteristics and material source. The results show that the groundwater quality in the study area varies greatly from north to south. In the northern inland area (AREA I), the main anions and cations are H C O 3 - and Ca2+, and the hydrochemical characteristics are mainly HCO3 − Ca, HCO3 ⋅ SO4 − Ca and HCO3 − Mg. The ion concentration distribution is uniform, and the groundwater quality is good. By using Gibbs plots and the ion proportional coefficient method, the main source of ions is the dissolution of potassium feldspar, albite and carbonate rock. In contrast, in the southern coastal area (AREA II), the main anions and cations are Cl− and Na+, and the hydrochemical characteristics are mainly Cl − Na. The ion concentration distribution presents a strong spatial difference. The closer the groundwater sampling point is to seawater, the worse the overall groundwater quality. Evaporite dissolution, seawater intrusion, cation exchange effects and human activities are the main factors affecting the groundwater quality in this area. In conclusion, the groundwater quality in northern inland area (AREA I) is better, mainly controlled by the dissolution of rocks. The groundwater quality in southern coastal area (AREA II) changes greatly, mainly controlled by seawater.

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First Attempts of the Use of 195Pt NMR of Phenylbenzothiazole Complexes as Spectroscopic Technique for the Cancer Diagnosis

Molecules ◽

10.3390/molecules24213970 ◽

2019 ◽

Vol 24 (21) ◽

pp. 3970 ◽

Cited By ~ 1

Author(s):

Bruna T. L. Pereira ◽

Mateus A. Gonçalves ◽

Daiana T. Mancini ◽

Kamil Kuca ◽

Teodorico C. Ramalho

Keyword(s):

Cancer Treatment ◽

Cancer Diagnosis ◽

Density Functional ◽

Chemical Shifts ◽

Chloride Ion ◽

Platinum Complexes ◽

Dft Method ◽

Ion Concentration ◽

Implicit Solvent ◽

Early Cancer Diagnosis

Platinum complexes have been studied for cancer treatment for several decades. Furthermore, another important platinum characteristic is related to its chemical shifts, in which some studies have shown that the 195Pt chemical shifts are very sensitive to the environment, coordination sphere, and oxidation state. Based on this relevant feature, Pt complexes can be proposed as potential probes for NMR spectroscopy, as the chemical shifts values will be different in different tissues (healthy and damaged) Therefore, in this paper, the main goal was to investigate the behavior of Pt chemical shifts in the different environments. Calculations were carried out in vacuum, implicit solvent, and inside the active site of P13K enzyme, which is related with breast cancer, using the density functional theory (DFT) method. Moreover, the investigation of platinum complexes with a selective moiety can contribute to early cancer diagnosis. Accordingly, the Pt complexes selected for this study presented a selective moiety, the 2-(4′aminophenyl)benzothiazole derivative. More specifically, two Pt complexes were used herein: One containing chlorine ligands and one containing water in place of chlorine. Some studies have shown that platinum complexes coordinated to chlorine atoms may suffer hydrolyses inside the cell due to the low chloride ion concentration. Thus, the same calculations were performed for both complexes. The results showed that both complexes presented different chemical shift values in the different proposed environments. Therefore, this paper shows that platinum complexes can be a potential probe in biological systems, and they should be studied not only for cancer treatment, but also for diagnosis.

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Broadband dielectric spectroscopy for monitoring temperature-dependent chloride ion motion in BiOCl plates

Scientific Reports ◽

10.1038/s41598-020-79018-2 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Adrian Radoń ◽

Dariusz Łukowiec ◽

Patryk Włodarczyk

Keyword(s):

Electrical Conductivity ◽

Dielectric Spectroscopy ◽

Low Frequency ◽

Chloride Ion ◽

Ion Source ◽

Chloride Ions ◽

Ion Concentration ◽

Broadband Dielectric Spectroscopy ◽

Free Chloride ◽

Structure Rebuilding

AbstractThe dielectric properties and electrical conduction mechanism of bismuth oxychloride (BiOCl) plates synthesized using chloramine-T as the chloride ion source were investigated. Thermally-activated structure rebuilding was monitored using broadband dielectric spectroscopy, which showed that the onset temperature of this process was 283 K. This rebuilding was related to the introduction of free chloride ions into [Bi2O2]2+ layers and their growth, which increased the intensity of the (101) diffraction peak. The electrical conductivity and dielectric permittivity were related to the movement of chloride ions between plates (in the low-frequency region), the interplanar motion of Cl− ions at higher frequencies, vibrations of these ions, and charge carrier hopping at frequencies above 10 kHz. The influence of the free chloride ion concentration on the electrical conductivity was also described. Structure rebuilding was associated with a lower concentration of free chloride ions, which significantly decreased the conductivity. According to the analysis, the BiOCl plate conductivity was related to the movement of Cl− ions, not electrons.

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