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C12H13N3O, triclinic, P1̄ (no. 2), a = 10.2233(9) Å, b = 10.2902(9) Å, c = 24.2253(19) Å, α = 86.607(7)°, β = 88.529(7)°, γ = 62.515(9)°, V = 2256.9(4) Å3, Z = 8, Rgt(F) = 0.0425, wRref(F2) = 0.1239, T = 291(2) K. [ABSTRACT FROM AUTHOR]

A new sesquiterpene lactone, 3β-O-β-d-glucopyranosyl-8α-hydroxy-11α,13-dihydrozaluzanin C (1), and a novel trinorguaiane-type sesquiterpene, 4β,10α-dimethyl-1β,5α-bicycle[3,5,0]dec-6-en-4α,10β-diol (2), together with three known compounds, glucozaluzanin C (3), 11α,13-dihydrozaluzanin C (4), and 8α-hydroxy-11α,13-dihydrozaluzanin C (5), were isolated from the whole plant of Ainsliaea fragrans Champ. The structures of 1 and 2 were elucidated on the basis of detailed spectral analysis. Structures of the known compounds were identified by comparison of its spectral data with those values in the literature. [ABSTRACT FROM AUTHOR]

Two new triterpenoid saponins, named ilexsaponins B4 (1) and C (2), have been isolated from the roots of Ilex pubescens. Their structures have been established as ilexgenin B 3-O-α-l-arabinopyranosyl-(2 → 1)-β-d-glucopyranosyl-(2 → 1)-β-d-xylopyranoside (1) and 3-O-β-d-xylopyranosyl spathodic acid 28-β-d-glucopyranosyl ester (2) by means of spectral and chemical methods. [ABSTRACT FROM AUTHOR]

Abstract: It has been a puzzle that transition metals can unexpectedly react with lithium-based matrixes of LiF and Li2O in the potential versus Li/Li+ range from 0.01 to 3.5V at room temperature. The electrochemical and theoretical investigations on the reactions of transition metals M (M=Co, Fe and Ni) with LiF and Li2O were carried out. The electrochemical reactivity of metal cobalt with LiF and Li2O has been examined by the discharge and charge, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) measurements. Density functional theoretical calculation results suggested that the stable compounds MLiF and MLi2O could be formed by the insertion of transition metal (M) in lithium-based matrixes with exothermic as an intermediate. The theoretical calculations provide an understanding in chemical reaction of M with LiF and Li2O. The small molecular or clusters reaction may play an important role in the electrochemical reaction of metal with transition Li2O or LiF, which could be used to explain for the unexpectedly reaction of transition metal with LiF and Li2O. [Copyright &y& Elsevier]

Background: Exposure to air pollutants has been related to preterm birth, but little evidence can be available for PM2.5, O3 and CO in China. This study aimed to investigate the short-term effect of exposure to air pollutants on risk preterm birth during 2014-2016 in Ningbo, China.Methods: We conducted a time-series study to evaluate the associations between daily preterm birth and major air pollutants (including PM2.5, PM10, SO2, NO2, O3 and CO) in Ningbo during 2014-2016. A General Additive Model extend Poisson regression was used to evaluate the relationship between preterm birth and air pollution with adjustment for time-trend, meteorological factors and day of the week (DOW). We also conducted a subgroup analysis by season and age.Results: In this study, a total of 37,389 birth occurred between 2014 and 2016 from the Electronic Medical Records System of Ningbo Women and Children's Hospital, of which 5428 were verified as preterm birth. The single pollutant model suggested that lag effect of PM2.5, PM10, NO2 reached a peak at day 3 before delivery and day 6 for SO2, and no relationships were observed for O3 and preterm birth. Excess risks (95% confidence intervals) for an increase of IQR of air pollutant concentrations were 4.84 (95% CI: 1.77, 8.00) for PM2.5, 3.56 (95% CI: 0.07, 7.17) for PM10, 3.65 (95% CI: 0.86, 6.51) for SO2, 6.49 (95% CI: 1.86, 11.34) for NO2, - 0.90 (95% CI: -4.76, 3.11) for O3, and 3.36 (95% CI: 0.50, 6.30) for CO. Sensitivity analyses by exclusion of maternal age < 18 or > 35 years did not materially alter our results.Conclusions: This study indicates that short-term exposure to air pollutants (including PM2.5, PM10, SO2, NO2) are positively associated with risk of preterm birth in Ningbo, China. [ABSTRACT FROM AUTHOR]

The thermal decomposition and de-hydroxylation process of dickite-potassium acetate (KAc) intercalated complex was studied using thermogravimetric (TG), differential thermal analysis (DTA), XRD and FTIR. The stability of intercalated complex was affected by heat treatment directly. The TG-DTA results showed that four changes had occurred at 64.5, 118, 301 and 406 °C, which can be attributed to (a) the loss of adsorbed water, (b) loss of the water linked to acetate ion in the layer of dickite, (c) decomposition of KAc, and (d) loss of water through de-hydroxylation, respectively. The XRD and FTIR results showed that when the heating temperature exceeded 400 °C, inner surface hydroxyls and inner hydroxyls lost gradually, generating amorphous meta-dickite. Further researches demonstrated that phase transition temperature of meta-dickite and mullite changed a lot through the intercalated KAc. [ABSTRACT FROM AUTHOR]