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Copyright of Acta Petrologica et Mineralogica / Yanshi Kuangwuxue Zazhi is the property of Acta Petrologica et Mineralogica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chinese Institute of Food Science & Technology / Zhongguo Shipin Xuebao is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Three pH values(5.0, 7.0, 9.0) were set to investigate the growth and algal toxin production of Microcystis aeruginosa under stress of low concentration pyrene (0.001 5 mg/L). The results showed that the growth of Microcystis aeruginosa under low concentration pyrene stress was significantly promoted under the condition of pH value, while the effect of toxin production was different under different pH value, with the expression as the cell density of the treatment group under low con- centration pyrene stress higher than that of the blank control group, and when pH is 9.0, the specific growth rate of Microcystis aeruginosa is the highest, and its generation time is also the shortest. The content of Chlorophyll a in the treatment group with low concentration of pyrene stress was lower than that in the blank control group, and at pH 9.0 and pH 7.0, the increase of Chlorophyll a was significantly greater than that at pH 5.0. Pyrene at low concentration at pH 7.0 inhibited the yield of intracellular and extracellular Microcystin-LR. Under the condition of pH 9.0, pyrene of low concentration promoted the yield of Microcystin-LR in and out of cells. The results showed that the growth of Microcystis aeruginosa and the yield of Microcystin-LR would be affected by pH value when there was low concentration of PAHs in water. Therefore, the pH value should not be ignored when assessing the risk of chemicals that promote Microcystin-LR production in eutrophic water. [ABSTRACT FROM AUTHOR]

According to the principles of simultaneous equilibria and mass equilibria, CuInSe2 (CIS) were prepared by total aqueous process at normal pressure and room temperature. A series of thermodynamic equilibrium equations were deduced for the complex system of Cu+-In3+-Se2--NH3-L2--Cl--H2O (T=298 K), and the equilibrium curves of lgc-pH were drawn. It was found from these equilibrium diagrams that[NH3]T primarily affected the[Cu+]T concentration,[L2-]T influenced the[In3+]T concentration, and[Cl-]T had impact on both. The highest precipitation coefficient was obtained at pH 7.0-8.5. As a result, based on the principles of simultaneous equilibria and mass equilibria of the Cu+-In3+-Se2--NH3-L2--Cl--H2O system (T=298 K) and used total aqueous process at normal pressure and room temperature, CIS nanoparticles can be synthesized by adjusting the pH value to 7.0-8.5, and their size is about 20 to 50 nm.

The effect of pH values on the corrosion behavior of Q235 steel in simulated acidic soils was investigated by weight-loss measurement, scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis and polarization curve analysis. When the pH values are 4.0, 4.5 and 5.1, the corrosion rate of Q235 steel are 0.68, 0.48 and 0.42 mm·a-1, respectively. With the increase of soil pH values, the rust becomes more compact and the etch pits change from narrow and deep to wide and shallow. All the corrosion products are mainly composed of SiO2, α-FeOOH, γ-FeOOH, Fe2O3 and Fe3O4, and the mass ratio of α-FeOOH/γ-FeOOH in the corrosion products is higher with increasing pH values. Additionally, polarization curve analysis shows that when the soil pH value rises, the corrosion potential of Q235 steel increases, the corrosion current density decreases, and the corrosion rate becomes lower.

Objective: To study the influence of environmental factors on the two-species biofilm formed by the combinations of Streptococcus oligofermentans (So) with Streptococcus mutans (Sm) and Streptococcus sanguinis (Ss) with Sm so as to evaluate the role of So in maintaining the microecological balance of the oral cavity. Methods: Single-and two-species biofilms were grown on saliva-coated surfaces (glass tube and 96-well plate). Colony-counting method and safranin staining method were used to measure the biofilms formed under various oxygen conditions (aerobic and anaerobic), sucrose conditions (0%, 1% and 5% sucrose concentrations) and pH conditions (5.5, 6.0, 6.5, 7.0, 7.5 and 8.0). Results: Comparing the numbers of Sm in two co-cultures under various conditions, Sm counts in So+Sm group [(7.70±2.46)×10(8) CFU/ml] were significantly lower than those in Ss+Sm group [(9.00±1.13)×10(8) CFU/ml] in aerobic environment ( P< 0.05). Sm counts in So+Sm group [(2.80±0.52)×10(8) CFU/ml] were also significantly lower than those in the Ss+Sm group [(4.00±1.25)×10(8) CFU/ml] in anaerobic environment ( P< 0.05). The Sm counts in So+Sm group [(8.90±0.82)×10(8) CFU/ml] were significantly higher than those in Ss+Sm group [(7.50±1.73)×10(8) CFU/ml] in 0% sucrose environment ( P< 0.05). The Sm counts in So+Sm group [(5.70±2.94)×10(8) CFU/ml] were significantly lower than those in Ss+Sm group [(10.30±3.21) ×10(8) CFU/ml] in 1% sucrose environment ( P< 0.05). The Sm counts in So+Sm group [(6.10±1.71)×10(8) CFU/ml] were also significantly lower than those in Ss+Sm group [(7.40±1.20)×10(8) CFU/ml] in 5% sucrose environment ( P< 0.05). The Sm counts in So+Sm group [(3.50±1.50)×10(8) CFU/ml] were significantly lower than those in Ss+Sm group [(10.70±2.80)×10(8) CFU/ml] in pH7.0 environment ( P< 0.05). Comparing the formation of biofilm after 24 h cultivation, the Sm counts in So+Sm group were significantly lower than those in Ss+Sm group both in aerobic and anaerobic environments ( P< 0.05). The Sm counts in So+Sm group were significantly higher than those in Ss+Sm group in 0% sucrose environment ( P< 0.05). The Sm counts in So+Sm group were significantly lower than those in Ss+Sm group in 1% and 5% sucrose and pH 7.0 environments ( P< 0.05). Both So and Ss had no inhibitory effect on Sm in pH5.5 and pH8.0 environments. Conclusions: In the in vitro two-species co-culture systems, So showed stronger inhibitory effects than Ss on Sm and its inhibitory ability might influenced by various environmental factors.