Publications by authors named "Chuan-yu Qin"

Background: To evaluate the myocardial microcirculation perfusion of patients with acute ST-segment elevation myocardial infarction (STEMI) with a different index of microcirculatory resistance (IMR) after percutaneous coronary intervention (PCI) by myocardial contrast echocardiography (MCE) and analyse the value of MCE in predicting myocardial perfusion after PCI.

Methods: Fifty-six patients with acute STEMI who underwent an emergency PCI were selected from October 2018 to October 2019 in our hospital. According to the IMR values measured during PCI treatment, the patients were divided into three groups.

View Article and Find Full Text PDF

A two-dimension simulated sand box was set up to investigate the influencing factors, such as the initial groundwater level, aeration rate and the initial groundwater rate, that affect groundwater circulation well (GCW) by determining the intensity of groundwater circulation which was characterized by the variation of groundwater level before and after aeration. The optimal operating parameters were used to remediate nitrobenzene contaminated aquifer. The results demonstrated that: GCW could be well operated under the conditions of 45 cm groundwater level, 0.

View Article and Find Full Text PDF

This paper presents the results of a laboratory investigation of the influence zone (IZ) of air sparging (AS) in different media at different surface tension. Different kinds of media were used in two-dimensional tank experiments, designed to determine (1) the effect of surface tension reduction on the airflow pattern during AS in different air travelling modes (channels and bubbles) in homogeneous aquifer and (2) the airflow distribution and migration characteristics in heterogeneous aquifer at different surface tension during AS. The results demonstrated that in homogeneous gravel aquifer, the IZ was almost identical with or without surfactant addition into groundwater, the air saturation, however, was increased with decreasing surface tension.

View Article and Find Full Text PDF

A two-dimensional laboratory sand tank was installed to study the remediation efficiency of surfactant-enhanced air sparging (-SEAS) coupled with soil vapor extraction (SVE) in nonaqueous phase liquid (NAPL) polluted sites. During initial stages of remediation, it was more reasonable to use conventional air sparging coupled with SVE. When most free NAPLs were removed and contaminant removal rate was maintained at a relatively low level, surfactant was added to the groundwater.

View Article and Find Full Text PDF

In an attempt to enhance the effectiveness of air sparging, two sets of experiments were designed to investigate the mechanisms and effect of surfactant-enhanced air sparging (SEAS). The first set was performed at different surface tensions and with different kinds of surfactants (sodium dodecyl benzene sulfonate and Tween-80 [Uniqema Americas LLC, Wilmington, Delaware]), which were added into the contaminated aquifer of different media (particle distribution size = 0.25 to 0.

View Article and Find Full Text PDF

This paper deals with the influencing factors on removal of chlorobenzene from unsaturated soils by soil vapor extraction (SVE) method. A series of one-dimensional column experiments were conducted to study the influencing factors for SVE method, the factors included extracted vapor flow rate, soil grain size, extraction mode, soil organic matter content and water content. The results indicated that: (1) the increase of vapor flow rate led to higher contaminant removal efficiency, but the increment of removal was not significant at higher flow rate levels; (2) soil grain sizes had a great impact on chlorobenzene removal efficiency, the coarser the sand, the higher the removal rate; (3) pulsed vapor extraction and continuous vapor extraction almost had the same contaminant removal effects in the sand column; (4) the higher organic content in the soil could decrease the removal efficiency; (5) water content in the soil had different impact on the contaminant removal efficiency which related with the organic content in the soil.

View Article and Find Full Text PDF