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The effect of vitamin D (VD) on the risk of preeclampsia (PE) is uncertain. Few of previous studies focused on the relationship between dietary VD intake and PE risk. Therefore, we conducted this 1:1 matched case–control study to explore the association of dietary VD intake and serum VD concentrations with PE risk in Chinese pregnant women. A total of 440 pairs of participants were recruited during March 2016 to June 2019. Dietary information was obtained using a seventy-eight-item semi-quantitative FFQ. Serum concentrations of 25(OH)D2 and 25(OH)D3 were measured by liquid chromatography–tandem MS. Multivariate conditional logistic regression was used to estimate OR and 95 % CI. Restricted cubic splines (RCS) were plotted to evaluate the dose–response relationship of dietary VD intake and serum VD concentrations with PE risk. Compared with the lowest quartile, the OR of the highest quartile were 0·45 (95 % CI 0·29, 0·71, Ptrend = 0·001) for VD dietary intake and 0·26 (95 % CI 0·11, 0·60, Ptrend = 0·003) for serum levels after adjusting for confounders. In addition, the RCS analysis suggested a reverse J-shaped relationship between dietary VD intake and PE risk (P-nonlinearity = 0·02). A similar association was also found between serum concentrations of total 25(OH)D and PE risk (P-nonlinearity = 0·02). In conclusion, this study provides evidence that higher dietary intake and serum levels of VD are associated with the lower risk of PE in Chinese pregnant women. [ABSTRACT FROM AUTHOR]

Based on the activity data of diverse ammonia sources, the rational estimation method and emission factors were employed, and an anthropogenic ammonia emission inventory was further established to describe the situation of Xi'an in 2013.The results showed that the total anthropogenic ammonia emission reached 47.17×10 3 t in 2013 with an emission intensity of 4.57 t·km -2 ; The livestock breeding and nitrogen fertilizers were the major sources of anthropogenic ammonia emission, which were 20.55×10 3 t and 17.51×10 3 t, respectively, accounting for 80.68% in total; Cow and hog were the major sources, and occupied 75.03% in livestock breeding emission; Lintong District was the heaviest emission area, the total emission was 10.73×10 3 t, which accounted for 23.22%; The emission intensity of Yanliang District reached 14.75 t·km -2 which was considered as the most severe area.

The soil with 500 m distance from an aluminum plant in Baotou was studied. A total of 64 soil samples were taken from the 0-5 cm, 5-20 cm, 20-40 cm and 40-60 cm layers, and the contents of Cu, Pb, Zn, Cr, Cd, Ni and Mn were tested, respectively. The correlation analysis and principal component analysis were used to identify the sources of these heavy metals in soils. The results suggested that the contents of Cu, Pb, Zn, Cr, Cd, Ni and Mn in study area were 32.9, 50.35, 69.92, 43.78, 0.54, 554.42 and 36.65 mg · kg⁻¹ respectively. All seven heavy metals tested were overweight compared with the background values of soil in Inner Mongolia. The spatial distribution of heavy metals showed that the horizontal distribution of heavy metals was obviously enriched in the southwest, while in vertical distribution, the heavy metal content (0 to 5 cm) was highest in the surface soil, and the heavy metal content decreased with increasing depth and tended to be stabilized when the depth was over 20 cm. Source analysis showed that the source of Cu, Zn, Cr and Mn might be influenced by the aluminum plant and the surrounding industrial activity. The source of Pb and Cd might be mainly related to road transportation. The source of Ni may be affected by agricultural activities and soil parent material together.

Using activated carbon as adsorbent, toluene waste gas was treated by adsorption process. After the adsorption process was completed, the adsorbent was desorbed by microwave irradiation; then Cu-Mn oxide composite catalysts were prepared by impregnation and the desorbed toluene gas was treated by catalytic combustion so as to completely purify the pollutant. The concentration of toluene was measured by gas chromatography (GC). The results indicated that it is feasible to add air to provide oxygen to the desorbed gas after the completion of the desorption process, in order to achieve the catalytic combustion; the ratio of desorbed gas and air was 1 : 1 (volume ratio), and the corresponding catalytic space velocity was 2.67 s(-1). Desorption temperature could affect the concentration of toluene in the desorption gas thereby affecting the catalytic combustion efficiency; the results indicated that 400 degrees C was an appropriate temperature for desorbing the activated carbon. When the catalytic combustion was kept at 300 degrees C, the final toluene treatment efficiency was higher than 90%, which was higher than 95% during the most time of the treatment process.

Objective: To study effective active constituents of Cayratia japonica,a genuine herbal medicine from Fujian., Method: Such chromatographic methods as Macroporous, Sephadex LH-20, ODS and normal phase silica gel column chromatography were adopted to separate the chemical components of C. japonica., Result: Thirteen compounds were obtained, and their structures were identified by analyzing multiple spectral data as luteolin(1), apigenin(2), triethyl citrate-(3), 3-formylindole(4), esculetin(5), bis(2-ethylhexyl)-phthalate(6), calendin(7), ethyl-trans-3,4-dihydr-oxycinnamate(8), luteolin7-O-D-glucoside(9),5-hydroxy-3,4-dimethyl-5-pentyl-2(5H-furanone(10),ethyl-3,4-dihydroxybenzoate(11), eriodictyol(12) and daucosterol(13)., Conclusion: Among them, compounds 3-8 and 10-12 were separated from the plant for the first time.

Granular activated carbon (GAC) was modified by microwave irradiation and electrical heating. The characters and toluene adsorption capacity of modified GAC were studied. The results showed that for microwave heating, with the temperature increasing, the activated carbon's ability of toluene adsorption and content of the surface basic functional group were increased, specific surface area was decreased. After heated at 850 degrees C, GAC had the highest ability for toluene adsorption, at 650 degrees C and 450 degrees C, the ability for toluene adsorption of GAC were similar. For the electrical heating, the same results were obtained. But the GAC modified with electrical heating had lower capacity of toluene adsorption than microwave modified GAC. The SEM photos showed that thermal modification made the porous structure of modified GAC smoother than original GAC, but the structure of GAC shrink at high temperature. Finally, all the experimental data and SEM photos were analyzed; it indicated that due to the difference of heating mechanism and heat transmission direction, the modified GAC have different characters.

Used a two-stage bench-scale temperature adjustable biofilter, biological treatment of medium and high concentration waste benzene and toluene vapor was investigated. The inlet vapor concentration (c(i)) was 0.9 - 5.0 g/m3. The results show that the biofilter can obtained good performance at 30 - 40 degrees C, and at 32.8 degrees C for benzene and toluene, the maximum elimination capacity (EC) of 136 g/(m3 x h) and 150 g/(m3 x h) is obtained at an inlet loading of 673.5 g/(m3 x h) and 665.0 g/(m3 x h), respectively. High media moisture is adverse to the biofilter performance. The optimum moisture for the biofilter is about 45% and the biofilter can obtain good performance at the moisture ranging from 40% to 50%. With the biofilter operation, pressure drop is increasing from 18 Pa to 39 Pa and leachate is changing from colorless to yellow, and these phenomena show that bioaccumulation is existent.