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Emission control of volatile organic compounds (VOCs) from industrial sources is a frontline defense against air pollution in China. Owing to the complexity of chemical processing technologies and reaction mechanisms of VOCs, it is extremely difficult to pinpoint specific emission sources in a large-scale industrial region due to the synergy of various chemical processes. In this research, a comprehensive on-site emission profile of a representative petrochemical industrial park in East China is set up with measurements conducted using photochemical assessment monitoring stations (PAMSs) and the TO-15 method as per the United States Environmental Protection Agency. This is followed by a quantitative ozone formation potential (OFP) analysis, toxification analysis, and an on-site health risk assessment, covering each of 18 major facilities’ three sections: the refinery, chemical manufacturing zone, and wastewater treatment zone. The number of facilities and detected species studied in this research exceeds that of a former similar study. This study shows that the majority of VOC emissions from those enterprises possessing the largest impact on the environment are hydrocarbons: alkanes, olefin (alkenes, alkynes), and aromatics (91% in total). Aromatics and olefins show the maximum contribution to OFP, which is consistent with the results of similar studies. VOCs, such as 1,3-butadiene, from refineries are key factors leading to long-term health impacts, with aromatics being a leading carcinogenic and noncarcinogenic factor.

The fibrinogen-to-albumin ratio index (FAR) is a valuable tool reflecting the systemic inflammation level and associated with the severity of coronary artery disease. However, the utility of the FAR in predicting the long-term prognosis of patients with ST-elevation myocardial infarction (STEMI) and multivessel disease has remained to be determined. A total of 424 patients diagnosed with STEMI and multivessel disease were recruited for the present study. They were given emergent percutaneous coronary intervention treatment and then completed a follow-up for primary (all-cause mortality) and secondary endpoints (major adverse cardiac events, including MI, stroke, emergent revascularization and rehospitalization due to heart failure). The association between FAR and the Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score was investigated, while receiver operating characteristic curve analysis was adopted to assess the ability of the FAR to predict long-term outcomes. The long-term survival of high and low FAR groups was compared by drawing Kaplan-Meier survival curves. Multivariate Cox regression analysis was adopted to evaluate the risk factors of primary and secondary endpoints. The FAR was revealed to have a linear correlation with the SYNTAX score (y=0.022x+17.737; P=0.015). Furthermore, the FAR was a significant predictor of all-cause death with a cut-off value of 128.4 (area under the curve, 0.832; P

A bolted beam-to-column connection with rib-stiffened splicing plates is presented to facilitate on-site assembly and enhance the stiffness of joints. The joints consist of three modules and are assembled using bolts on site. Cyclic tests and a finite element analysis (FEA) are performed on seven full-scale joints. The influence of the trapezoidal stiffener's size, end-plate connection type, and the number of bolts on the seismic performance of the joints is investigated. The seismic performance of the bolted joints is compared with that of a welded joint. The failure mode, hysteretic curve, energy dissipation capacity, ductility, rotation capacity, bolt tension, friction, strength, and stiffness of the joints are determined via the tests and FEA. The trapezoidal stiffener significantly improves the bearing capacity, stiffness, and energy-dissipation capacity of the joints, making the plastic hinge occur on the beam flange outside the splicing zone. It is preferable to move the web bolts to the beam flange for improved seismic performance. The bolts on the four corners of the column flange have little effect on the seismic performance; thus, the bolts can be eliminated and the flange can be substituted by four small plates to reduce cost. This reasonable design could prevent the slipping of the joint during small-magnitude earthquakes, facilitate energy dissipation via slip during medium-magnitude earthquakes, and facilitate energy dissipation via the slip and plastic deformation of the beams during large-magnitude earthquakes. The formula for the ultimate load is presented, and the corresponding calculation results agree well with the test results.