Search

• The perovskite film was prepared by ultrasonic spraying method. • Isopropyl alcohol (IPA), a green solvent with low boiling point, was introduced into perovskite precursor solution. • IPA-based PSCs exhibit the champion device efficiency of 22.43 %. The ultrasonic spray coating has been shown to be an effective technique for scaling up production. The nucleation and crystallization process of the perovskite film prepared by the ultrasonic spraying approach is more complicated than that by the spin coating, but they are essential to gaining efficient perovskite solar cells (PSCs). At the same time, the green solvent is the primary problem that must be solved in the process of PSCs commercialization. In this paper, the low boiling point and green solvent isopropyl alcohol (IPA) is introduced into the perovskite precursor solution to prepare FAPbI 3 perovskite by ultrasonic spraying. The addition of IPA enhanced the saturated vapor pressure of the precursor solution, which can create the local chemical microenvironment on the film surface and subsequently retard the nucleation rate from 8.31 s to 8.54 s at nucleation stage. The local chemical improves the initial homogeneity of the sol–gel phase and then leads to improved structural and optoelectronic properties within the FAPbI 3 film via sufficient crystallization from the sol–gel phase to α-FAPbI 3. Ultimately, IPA-based PSCs exhibit the champion device efficiency of 22.43 %. The good long-term stability of PSCs (maintain more than 90 % of the initial efficiency after 1000 h, and keep 80 % after 400 h) in ambient conditions. [ABSTRACT FROM AUTHOR]

• 124 volatile compounds during the storage of organic green tea by SDE-GC–MS were identified. • Variations of volatile compounds in organic green tea during storage (1–16 years) were explored. • Key volatile compounds related to the storage years were screened. • The content of six volatile compounds showed good predictive ability for the storage years. In the present study, the volatile compounds in organic green tea with a continuous storage period (ranging from 1 to 16 years) were comprehensively analyzed and compared through SDE-GC–MS and chemometrics. The results revealed that the total of 124 volatiles were identified, and their total amount was increased with the prolongation of the storage years. Ketones, alcohols, esters, and aromatic hydrocarbons were the main types of volatiles in organic green tea, among which 26 volatile compounds were significantly correlated with storage years, and six volatile compounds that were most seriously affected by the storage years. The results of the support vector machine classification combined with multiple linear regression analysis showed that the content-period prediction model for the six volatile compounds can accurately predict the storage years of organic green tea. Therefore, this study offers novel insights into volatile compounds changes during the storage of green tea. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome (mitogenome) of the Ectropis obliqua (Lepidoptera: Geometridae) was sequenced and compared with other species of Geometridae. The mitochondrial genome of E. obliqua is 15,475 bp long and contains 37 genes including 13 protein coding genes (PCGs), 22 transfer RNA genes, 2 ribosomal RNA genes and an A + T-rich region. Gene cluster trnI - trnQ - trnM rearranged to trnM - trnI - trnQ comparing with the ancestral mitogenome of insects. All tRNA genes have typical cloverleaf secondary structure except for trnS (AGN). All the sequenced mitogenomes from Geometridae have negative AT-skews and positive GC-skews except for Biston suppressaria . The synonymous and nonsynonymous substitutions ratios (Ka/Ks) indicated variable selective pressures among 13 PCGs. The phylogenetic relationship among 11 species of Geometridae was recovered based on 13 protein coding genes and 2 rRNA genes using Bayesian inference. E. obliqua is grouped with other Ennominae species and recovered to be sister-relationship with Abraxas suspecta . [ABSTRACT FROM AUTHOR]

Abstract: Hot-water extracts of low-grade green tea were precipitated with ethanol, deproteinized with trichloroacetic acid, neutralized with NaOH and fractionated by DEAE-cellulose DE-52 column chromatography to yield three (3) of unexplored polysaccharide-conjugate fractions termed gTPC1, gTPC2 and gTPC3. Monosaccharide and amino acid composition, contents of total neutral sugars, proteins and moistures, HPGPC distribution and Zeta potentials of gTPC1–3 were investigated. Exposure of human umbilical vein endothelial (HUVE) cells to high glucose (33mM) for 12h significantly decreased cell viability relative to normal glucose control (p <0.001). As compared with cell injury group, gTPC1–3 at all of three dose levels (50, 150 and 300μg/mL) were found to possess remarkably protective effects on HUVE cells against impairments induced by high glucose in a dose-dependent manner (p <0.05, p <0.001). To contribute toward our understanding of the cell-based protection mechanism of gTPC1–3, the latter were subjected to self-oxidation of 1,2,3-phentriol assay, and their scavenging effects were observed as 55.1%, 47.6% and 47.9% at the concentration of 300μg/mL, respectively. On the basis of the fact that high glucose-induced endothelial dysfunction involves in the overproduction of reactive oxygen species (ROS) and contributes to the vascular complications in patients with diabetes, inhibitory effects of gTPC1–3 on high glucose-mediated HUVE cell loss are, at least in part, correlated with their potential scavenging potency of ROS. Taken together, gTPC1–3 could be developed as non-cytotoxic candidates of therapeutic agent for diabetic vascular complications. [Copyright &y& Elsevier]