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The power supply accident caused by the corrosion of metal materials in the substation has become an important issue that affects the safe operation of the power grid. The corrosion of copper T2 was the most serious. The corrosion behaviour of copper T2 in SO2- and H2S-containing atmospheric environments was investigated using electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), and X-ray diffraction (XRD), and the nonequidistant grey GM(1,1) model was established of which the precision and forecast dependability were evaluated. Results indicated that the corrosion rate of copper in the SO2 environment increased in the early stages of corrosion and then gradually decreased at the later stages. In contrast, the corrosion rate of copper in the H2S environment slowly increased in the early stages of corrosion and then sharply increased at the later stages. The corrosion products in the SO2 environment consisted of cuprite (Cu2O) and brochantite [Cu4(OH)6SO4], whereas the corrosion products in the H2S environment were Cu2O and chalcocite (Cu2S). The mathematical model has good prediction dependability and higher forecast reliability.

Flammability in esters is one of the most important features for preparation, storage, safe processing, handling and shipping of a substance. In this study, a new accurate group contribution-based method was presented for estimation of the flash points of ester compounds. The predicted flash points for a dataset of 80 esters were in good agreement with the experimental values. The obtained results showed the squared correlation coefficient (R2) of 0.9902, root mean square error (RMS) of 5.371K, and average absolute relative deviation (AARD) of 1.22% for the experimental values. To propose a predictive model, 30 ester compounds in testing set were investigated. The average percent error of 1.96% for the predicted flash point of the investigated compounds was found from the corresponding experimental values. The established model was validated and tested through the use of leave-one-out cross validation method, Y-randomization and applicability domain analysis. The results demonstrated the improved accuracy of the presented method with respect to previously proposed methods in open literatures. Therefore, the model can be well used to predict the flash points of a wide range of ester compounds, which is an accurate method for potential application.

A new nano-TiO_2 multiplex photocatalyst codoped with Eu~(2+)and Gd~(3+)was prepared by a modified acidic sol-gel process.TEM and XRD results demonstrate that as-produced samples are anatase structure,and the crystallite size has relationship only with total doped Eu~(2+)/Gd~(3+)content and the minimum size appeares at 1% doped content.UV-Vis absorption spectra show that Eu~(3+)/Gd~(3+) codoping can enhance the visible light response of the TiO_2.The photocatalyst activity of Eu~(2+)/Gd~(3+) codoped TiO_2 is evaluated by photodegradation of methyl orange in an aqueous solution under natural light irradiation,A synergetic effect is observed due to Eu~(2+)/Gd~(3+)codoping,and the optimal doping concentration for Gd~(3+)and Eu~(2+)are in the range from 0.1% to 1.0% and 0.5% to 1.5% respectively. The relationship and function between Eu~(2+),Gd~(3+)and TiO_2 are also discussed.

The title compound was prepared by using α-SiW 9 as precursor and was characterized by IR, UV–Vis–NIR spectroscopy. Its crystal structure was determined by X-ray diffraction. The compound crystallized in monoclinic system, space group P 2 1 with a =12.599(3), b =12.649(4), c =17.814(4)A, γ =90.11(3)°, V =2838.9(10)A 3 , Z =2, Mr =2966.24 g mol −1 , D c =3.467 g cm −3 , λ (MoK α )=0.71073 A, μ =19.279 mm −1 , F (000)=2634. The final R =0.0666, Rw =0.0865. The title compound consists of heteropoly anions, potassium ions and water molecules. The anion has the well-known Keggin structure and the 12 metal atoms in the anion were in a random distribution.

The main objective of this paper was to investigate the extraction process of ethanol extract of Radix Semiaquilegiae, as well as its inhibitory activity on human hepatoma HepG-2 and SMMC-7721 cells, and to compare the inhibitory effects of different concentrations of ethanol extracts against these two hepatoma cells. Ethanol reflux extraction and ultrasound-assisted extraction with ethanol at room temperature were used in the extraction process, and MTT assay was mainly used in the activity experiment to perform in-vitro anti HepG-2 and SMMC-7721 cell activity screening of ethanol extract, and to calculate the cell inhibition rates of the extracts. The results showed that among the two types of extracts, ethanol reflux extract had more superior antitumour activity to that of the ultrasonic extract, but all of the extracts obtained had certain anti-cancer activities, and the anti-proliferative activity increased with the increase of concentration.

Prostate cancer is the second most common cause of mortality. Gallic acid (GA) is a natural polyphenol, and we tested its in-vitro cytotoxicity after 24 h in prostate cancer LNCaP cells.GA autoxidation was measured fluorimetrically for H(2)O(2), and O(2)(•-) radicals by chemiluminescence. Intracellular reactive oxygen species (ROS) levels were detected with 2',7'-dichlorodihydrofluorescein diacetate. Cytotoxicity was evaluated by crystal-violet, while apoptosis and mitochondrial membrane potential were determined by flow cytometry. Cytochrome c release was detected by enzyme-linked immunosorbent assay, and caspase-8, -9 and -3 activities were measured calorimetrically.GA autoxidation produced significant levels of H(2)O(2) and O2.-. Increased intracellular ROS levels with GA were reduced by N-acetyl-L-cysteine (NAC) and L-glutathione (GSH). Cells were protected against GA cytotoxicity when pretreated with increasing levels of superoxide dismutase/catalase mixture, NAC, or GSH for 3 h. The number of apoptotic cells increased with GA dose. GA caused mitochondrial potential loss, cytochrome c release, and activation of caspases 3, 8 and 9.The ROS-dependent apoptotic mechanism of GA kills malignant cells effectively; it is likely that GA could be a good anticancer agent.

Prostate cancer is one of the most commonly diagnosed solid malignancies among US men. We identified gallic acid (GA) as a major bioactive cytotoxic constituent of a polyherbal Ayurvedic formulation - triphala (TPL). Both TPL and GA were evaluated on (AR)(+) LNCaP prostate cancer and normal epithelial cells.Total polyphenols in TPL were determined using Folin and Ciocalteu method, followed by GA quantitation by high performance liquid chromatography. Cell toxicity was evaluated by crystal violet after 24, 48, 72 and 96 h.TPL contains 40% unidentified polyphenolic acids, of which 2.4% comprised GA. GA induced severe morphological alterations and was about 3-fold more cytotoxic towards cancer cells than TPL. This activity increased further in the presence of dihydrotestosterone. GA toxicity on normal cells was low at 72 h. Combination of GA with flutamide caused higher toxicity to cancer cells than either of the compounds alone.GA appears to have promising anticancer activity.

Two distinct types of debranching enzymes have been identified in developing pea (Pisum sativum L.) embryos using native gel analysis and tests of substrate preference on purified or partially purified activities. An isoamylase-like activity capable of hydrolyzing amylopectin and glycogen but not pullulan is present throughout development and is largely or entirely confined to the plastid. Activities capable of hydrolyzing pullulan are present both inside and outside of the plastid, and extraplastidial activity increases relative to the plastidial activity during development. Both types of debranching enzyme are also present in germinating embryos. We argue that debranching enzymes are likely to have a role in starch metabolism in the plastid of the developing embryo and in starch degradation during germination.