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The urban stormwater flood and its ecological effects are becoming increasingly prominent underlying the rapid urbanization of China. Nanning is a typical southern city with frequent flood disasters and an urgent need to conduct quantitative research and explore effective countermeasures. Therefore, the quantitative contributions of rainfall, evapotranspiration (ET), and landscape patterns to urban stormwater runoff are analysed using the Budyko framework in this paper. The results show that the rainfall, landscape pattern, evapotranspiration and runoff in Nanning have significant synergistic interaction. The change of rainfall has a positive effect on runoff increment, accounting for 5.9~12.3% of the annual rainfall. The change of the underlying surface parameter (n) has a negative effect on runoff decrement, accounting for −14.8%. Evidently, the blue (water space), green and grey infrastructure of the underlying surface and its spatial pattern largely determine the quantity and spatial distribution of storm runoff in Nanning City. [ABSTRACT FROM AUTHOR]

Di‐n‐pentyl phthalate (DPeP) is an endocrine‐disrupting phthalate plasticizer. The objective of this study was to investigate the effect of DPeP on adrenocortical function in adult male rats following in utero exposure. DPeP (0, 10, 50, 100, and 500 mg/kg/day) was administered by gavage to pregnant Sprague–Dawley rats from gestational day 14 to 21. The morphology and function of the adrenal cortex in 56‐day‐old male offspring were studied. DPeP at 100 and 500 mg/kg/day significantly reduced serum aldosterone levels and at 500 mg/kg/day markedly reduced corticosterone and adrenocorticotropic hormone levels. DPeP at 10–500 mg/kg markedly reduced the thickness of zona glomerulosa without affecting the thickness of zona fasciculata. DPeP significantly downregulated the expression of Agtr1a, Mc2r, Scarb1, Cyp11a1, Hsd3b1, Cyp21, Cyp11b1, Cyp11b2, Nr5a1, Nr4a2, and Bcl2 genes as well as their proteins. DPeP at 500 mg/kg/day significantly increased phosphorylated AMPK, while DPeP at 100 mg/kg/day and higher doses reduced phosphorylated AKT1 and total SIRT1 level. DPeP at 100 and 500 μM markedly induced reactive oxygen species and apoptosis in H295R cells after 24 h of culture. In conclusion, in utero exposure to DPeP disrupts adrenocortical function of the adult male offspring by (1) increasing AMPK phosphorylation and decreasing AKT1 phosphorylation and SIRT1 levels, (2) reducing adrenocorticotropic hormone levels, and (3) possibly inducing oxidative stress and apoptosis. [ABSTRACT FROM AUTHOR]

Phthalates may interfere with the biosynthesis of steroid hormones in the adrenal cortex. Bis (2‐butoxyethyl) phthalate (BBOP) is a phthalate containing oxygen atoms in the alcohol moiety. In this study, 35‐day‐old male Sprague–Dawley rats were daily gavaged with BBOP (0, 10, 100, 250, and 500 mg/kg body weight) for 21 days. BBOP did not affect the weight of body and adrenal glands. BBOP significantly reduced serum corticosterone levels at 250 and 500 mg/kg, and lowered aldosterone level at 500 mg/kg without affecting adrenocorticotropic hormone. BBOP did not alter the thickness of the adrenal cortex. BBOP significantly down‐regulated the expression of steroidogenesis‐related genes (Scarb1, Star, Cyp11a1, Cyp21, Cyp11b1, Cyp11b2, Nr5a1, Nr4a1, and Nr4a2) and proteins, and antioxidant enzymes (Sod1, Sod2, Gpx1, and Cat) and their proteins, while up‐regulating the expression of Mc2r and Agtr1a at various doses. BBOP reduced the phosphorylation of AKT1, AKT2, and ERK1/2, as well as the levels of SIRT1 and PGC1α without affecting the phosphorylation of AMPK. BBOP significantly induced the production of reactive oxygen species and apoptosis rate in H295R cells at 100 μM and higher after 24 h of treatment. In conclusion, male rats exposed to BBOP in puberty have significant reduction of steroid biosynthesis with a potential mechanism that is involved in the decrease in the phosphorylation of AKT1, AKT2, ERK1/2, as well as SIRT1 and PGC1α and increase in ROS. [ABSTRACT FROM AUTHOR]

More and more polyimide (PI) mixed matrix membranes (MMMs) have been reported for gas separation. In this study, a novel PI MMM, named as PI/SNW-1 and composed of PI and Schiff base network (SNW) type covalent organic frameworks (COFs) SNW-1, was used for gas permeation measurements of carbon dioxide (CO2) and methane (CH4). The prepared PI/SNW-1 was investigated by the Fourier transform infrared spectroscopy, the field emission scanning electron microscopy, and the thermal gravimetric analysis. The results indicated that PI/SNW-1 had maintained a high thermal stability and uniform distribution of filler. Compared with the pure PI membrane, MMMs showed an increment of 48.7% in ideal selectivity of CO2/CH4 and an enhancement of 106.4% in CO2 permeability at 5 wt% SNW-1. The enhancement of permeability and selectivity was mainly attributed to the high porosity of SNW-1, the specific sorption affinity for CO2, and the close interface interaction with the PI matrix. It can be seen that PI/SNW-1 has a great potential for actual gas separation. [ABSTRACT FROM AUTHOR]

A shape-persistent macrocycle consisting of 2,6-disubstituted aniline linked by acetylene, butadiyne, and an inner tetraethylene glycol bridge was prepared by Pd/Cu homocoupling oxidation reaction. The morphology of the resulting macrocycle was demonstrated and discussed, indicating the establishment of channels with amine functional groups inside the pores. Polarized optical microscopy (POM) observation of the macrocycle indicated the formation of liquid crystals (LCs) in the heating and cooling processes. [ABSTRACT FROM AUTHOR]

Abstract: A typical of network-like polyimide/silica composite microspheres with a high SiO2 content was successfully prepared by a suspension polymerization method. The microstructure, morphology, surface composition and thermal property were characterized by infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analyzer (TGA), respectively. The results showed that the size of PI/SiO2 composite microspheres with 20–25μm presented rough surface and an interpenetrating network had formed inside the spheres. The temperature of 5% weight loss was at about 503°C, having higher thermal stability than pure PI. [Copyright &y& Elsevier]