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The structure parameter of the forward osmosis membrane has been defined as the characteristics of the support membrane, not related to the separation layer. Therefore, studies for improving the performance of the forward osmosis (FO) membranes have been focused on the optimization of the support structure. This study demonstrates that the separation thin-film polyamide (PA) layer has a strong impact on the performance of the FO membrane thus the structure parameters (S). We intentionally utilized a polyethersulfone hollow fiber substrate and two types of active separation skin were prepared at the inner surface: the first MPD/TMC and the second by adding triethylamine (TEA) into the aqueous phase during the interfacial polymerization (IP). By adding TEA, a rough PA layer with a leaf-like structure and a high crosslinking degree was obtained followed with high FO flux and low reverse salt flux attributed to the increased effective filtration area and crosslinking degree. The structure parameter of the FO membrane was reduced from 0.78 mm (for MPD/TMC system) to 0.45 mm (for MPD-TEA/TMC system). The result indicated that for the same substrate, lower structure parameter corresponded to the skin layer with higher permeance and rejection. This study confirmed that the structure parameter is more an inherent property of the entire TFC FO membrane than the character of the porous substrate. Future design for FO membranes needs to regulate the substrate, but more importantly to optimize the separation layer. • An approaching ratio (α) was designed as a simple guideline for control the structure parameter of FO membranes. • Diethylene glycol was used as the nonsolvent to control the approaching ratio. • Lowest structure parameter and highest FO performance were obtained at α = 50 %. • The optimized TFC membrane is of practical interest for lithium concentration. [ABSTRACT FROM AUTHOR]

Objective To explore the correlation between metabolic syndrome (MS) and noise-induced hearing loss (NIHL) in noise-exposed workers. Methods Using the convenient sampling method, a total of 850 male noise-exposed workers in an automobile manufacturing enterprise were studied. The questionnaire survey and occupational health examination were combined to collect general demographic data, physical examination data, and other information. According to the results of high-frequency hearing loss, the noise-exposed workers were divided into the hearing loss group (326 workers) and the normal hearing group (524 workers). The single-factor analysis was used to compare the above data differences between the two groups. The binary multiple-factor logistic regression model was used to analyze the influencing factors of NIHL in noise-exposed workers. Results The non-compliance rate of noise intensity in the enterprise was 39.47% (15/38), with the highest occurrences in the welding and painting posts. The morbidity of hearing loss was 38.35% (326/850), and the MS morbidity was 27.53% (234/850). The frequency of obesity, high-level triglyceride, high-level fasting blood glucose, hypertension, MS,and the contact noise level in the hearing loss group were higher than those in the normal hearing group (P < 0.05). The results of multiple-factor logistic regression showed that, compared with the workers with a noise exposure duration ≤ 5 years, the risk of NIHL in the workers with a noise exposure duration of 11 - 15 years or > 15 years increased to 1.553 and 1.727 times, respectively (P < 0.001). Compared with the workers without MS, the risk of NIHL in the workers with MS increased to 1.863 times (P < 0.001). The risk of NIHL increases by 1.567 times for each 1 dB(A) increase in noise level (P < 0.001). Conclusions There was a correlation between MS and NIHL. In addition to emphasizing control of noise level in the workplace, attention should also be paid to adopting a low-sugar, low-salt, and low-sodium diet, reducing the intake of saturated fatty acids, and strengthening physical exercise to effectively control the blood pressure, blood sugar, and blood lipid levels of workers so as to reduce the risk of NIHL. [ABSTRACT FROM AUTHOR]