JOURNAL OF CONTAMINANT HYDROLOGY
·
2020
·
IF 2.347
Xinran Song,Jiajun Chen,Qi Xu,Yiti Wang
To study the interactions between remediation agent injection and hydrodynamic dispersion as well as the expansion of a contamination plume, a two-dimensional sandbox experiment was conducted to simulate and monitor the mixing of a remediation agent in the contamination plume and the expansion of the contamination plume over time. Potassium permanganate is a purple solution, and it represents the remediation agent; Perchloroethylene (PCE), is dyed green and was used to observe the migration and diffusion of the contaminant and the overlap of contamination and the agent-plume. Six quantitative characterization parameters: migration distance, ( d M ), migration area, ( A M ), initial area ratio, ( K i ), spreading speed difference, ( SSD ), area ratio, ( K A ) and migration distance ratio, ( K d ), are proposed to comprehensively analyse the influence of the three factors of injection pressure, particle size and viscosity change on the mixing of a remediation agent and the expansion of the contamination plume over time. The results show that these six parameters can effectively characterize the mixing of the remediation agent and the expansion of the contamination plume, where d M , A M and K i characterize the expansion and the other three parameters characterize the mixing. The factors increasing the expansion of the contamination plume follow the order: 40 cm > 30 cm > 20 cm, for injection pressure (water head); coarse sand > medium sand > fine sand for particle size; and no polymer added > added polymer 200 mg/L > added polymer 800 mg/L > added polymer 400 mg/L for viscosity adjustment. The factors that intensify the mixing of the remediation agent in the contamination plume follow the order: 20 cm > 30 cm > 40 cm (water head); coarse sand > medium sand > fine sand; and added polymer 400 mg/L > added polymer 200 mg/L > no polymer added> added polymer 800 mg/L. Finally, conclusions from the TOPSIS method show that under optimal injection conditions, mixing is enhanced without increasing plume expansion and that the optimum injection conditions are injection pressure = 20 cm, use of a coarse sand medium, and added polymer concentration = 400 mg/L.
研究领域:
环境科学
·
水文学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2019
·
IF 3.021
Shengchao Xu,Wenbo Zhao,Muyuan Chai,Tian Si,Yuan Chen,Qingming Jia
As phase change absorption of CO2 could drastically reduce energy consumption, a liquid–liquid phase change absorption process of SO2 was developed in the present work using N,N-dimethylethanolamine (DMEA) as absorbent and hexadecane as solvent. The homogeneous solution was split into two immiscible phases when the absorption capacity reached 0.02 mol/mol. The phase change mechanism was attributed to the formation of a zwitterionic compound, through the reaction of SO2 with DMEA and its separation from the solution. The viscosity of the absorption product was related to the absorption capacity and temperature, which is described by an Arrhenius-type equation. The gravimetric absorption capacity was found to be 1.56 g SO2/g DMEA at 1.0 atm, which is the highest value reported in the literature. At 0.02 atm, its capacity still reached 0.59 g/g, which is also much higher than those of other absorbents at similar conditions. The distribution of DMEA, hexadecane, and SO2 in the two phases is described by two differential equations and material balance. Ternary phase diagram representation was used to provide an intuitive visual of the phase separation behavior. High temperature was found to play a role in weakening phase separation. Ultimately, DMEA was chemically regenerated by the reaction of the absorption product and cyclohexene oxide.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2022
·
IF 8.008
Weijia Xu,Senyao Liu,Zhaoming Chen,Fapu Wu,Wenwen Cao,Yang Tian,Hu Xiong
Simultaneous detection of different diseases via a single fluorophore is challenging. We herein report a bichromatic fluorophore named Cy-914 for the simultaneous diagnosis of non-alcoholic fatty liver disease (NAFLD) and metastatic intestinal cancer by leveraging its NIR-I/NIR-II dual-color imaging capability. Cy-914 with a pKa of 6.98 exhibits high sensitivity to pH and viscosity, showing turn-on NIR-I fluorescence at 795 nm in an acidic tumor microenvironment, meanwhile displaying intense NIR-II fluorescence at 914/1030 nm under neutral to slightly basic viscous conditions. Notably, Cy-914 could sensitively and noninvasively monitor viscosity variations in the progression of NAFLD. More importantly, it was able to simultaneously visualize NAFLD (ex/em = 808/1000–1700 nm) and intestinal metastases (ex/em = 570/810–875 nm) in two independent channels without spectral cross interference after topical spraying, further improving fluorescence-guided surgery of tiny metastases less than 3 mm. This strategy may provide an understanding for developing multi-color fluorophores for multi-disease diagnosis.
研究领域:
医学影像学
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分子生物学
·
病理学
✓ 已验证
DOI
高影响因子
PLoS One
·
2024
·Vol. 19
·期 9
·e0308424
·
IF 2.9
Yulin Liu,Longzhan Dong,Wenli Wu,Jiantao Ping,Jingbo Chen,Qiongzheng Hu
Hardness is one of the basic parameters of water, and a high-level hardness of drinking water may be harmful to human health. Thus, it is very important to monitor drinking water hardness. In this work, a portable lateral flow distance-based paper sensor for the semi-quantitative detection of drinking water hardness is demonstrated. In the presence of Ca 2+ /Mg 2+ , the hydrogel can be formed via the chelation between sodium alginate and Ca 2+ /Mg 2+ , inducing a phase separation process. The viscosity change of the sodium alginate solution is directly related to the Ca 2+ /Mg 2+ concentration and can be determined by the water lateral flow distance on test strips. The sensor successfully realizes the quantification of Ca 2+ and Mg 2+ in the range of 0–10 mmol L -1 and 4–20 mmol L -1 , respectively. The recoveries are found varied from 95% to 108.9%. The water hardness is acceptable for drinking if the C r values lies in the range of 0.259 to 0.419, and it is high with the C r value above 0.595. Remarkably, the performance of the sensor is comparable with the commercial kit for real water samples, which avoids the subjective judgment. Overall, this method provides a portable approach for semi-quantitative detection of drinking water hardness with the merits of convenience and low cost, which shows great potential for the potential application.
研究领域:
环境科学
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分析化学
·
水质监测
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）