A series of H2O2 decomposition experiments were performed in the presence of Cu-MSMs without PhACs (Fig. 7) where H2O2 finally decomposed into O2. The decomposition rate had the order of M1 < M2 < M3 < M4, suggesting that GKPIPNPLLGLDST these catalysts exhibited the opposite reactivity for the decomposition of H2O2 compared to the degradation of PhACs, and the rate of H2O2 disappearance increased with increasing the ratio of extraframework copper in Cu-MSMs. M2 exhibited the highest catalytic activity toward the PhACs degradation and lower activity for the H2O2 decomposition, indicating that the framework copper species in Cu-MSMs were extremely selective for promoting Fenton chemistry with minor spurious decomposition of H2O2 to O2. Since oxygen vacancies took part in the decomposition of H2O2 into O2, M4 showed the highest activity for the decomposition of H2O2 due to its higher concentration of oxygen vacancies, which were produced by the extraframework copper species in the form of aggregated copper oxide clusters. In our previous study , no OH formation was determined with the decomposition of H2O2 in aqueous CuOx–H2O2 suspension, confirming this mechanism.
The following materials were used: one type of cement complying with NP EN 197-1  (cement type I-42.5 R with specific gravity of 3.14) whose chemical composition and grading are provided in Table 1 and Table 2, respectively; two mineral admixtures: fly ash (FA) complying with NP EN 450-1  and NP EN 450-2  with specific gravity of 2.30 and limestone filler (LF) complying with specification LNEC-E466  with specific gravity of 2.72, whose chemical composition and grading are given in Table 1 and Table 2, respectively; two limestone coarse Sulfo-NHS-Biotin complying with NP EN 12620 , gravel 1 with specific gravity of 2.59, Dmax of 11 mm and water absorption of 1.46% and gravel 2 with specific gravity of 2.64, Dmax of 20 mm and water absorption of 0.78%; two siliceous sands complying with NP EN 12620 , one coarse (0/4) with specific gravity of 2.55, fineness modulus of 3.70 and water absorption of 1.10% and one fine (0/1) with specific gravity of 2.58, fineness modulus of 2.03 and water absorption of 0.70%; a third-generation high-range/strong water-reducing admixture (Sp) complying with NP EN 934-1  and NP EN 934-2  (a modified polycarboxylic high-range water-reducing admixture in liquid form with a density of 1.07) and tap water complying with NP EN 1008 .
Further process disturbances, starvation and alkalization, were investigated at the HRT of 8 h. In order to keep the reactor in starvation conditions, the feeding pump was stopped for 1 day. Thus, feed was not provided to the microbes, leading to a starvation period. This is, to the best of the authors’ knowledge, the first report of starvation condition in biohydrogen fermentation. The HPR dropped down to 5.0 L/L-d during the starvation phase, but recovered to 11.6 L/L-d in 5 days after the substrate was fed again. During this gamma-Secretase inhibitor IX period, the biohydrogen content was not largely affected, ranging between 38% and 53%. The effect was studied only for a shorter period of 5 days. It may be worthy of mention that the day after starvation occurred, the issue was rectified. However, significant changes were not noted in the biomass concentration, with only slight variation between 4.68 and 4.74 g VSS/L. This could clearly explain that the amount of substrate feed in to the reactor or the remaining feed in the reactor are very important and critical factors for the better production performance. The effluent pH also showed little variation from the maintained value of 5.5. In addition, the sugar utilization rate did not change much, ranging over 99% degradation. The VFA pattern was slightly changed, which will be discussed further below.
Appendix A. Supplementary data
Supplementary data 1.
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Immobilization; Heavy metals; Sodium sulfide (Na2S); Sodium diethyl dithiocarbamate (DDTCNa); Metal sulfide precipitates
Heavy metals such as copper and zinc are essential micronutrients and vital to all living organisms. However, elevated heavy metal concentrations in soil may cause toxic effects on soil organisms and can affect soil Apicidin functioning  and . Recently, with the rapid development of industrialization and economic, indiscriminate waste disposal practices have led to significant build–up in soils of a wide range of metals, and many health authorities are becoming increasingly concerned about the effects of heavy metals on environment and human health ,  and .
Sodium diethyl dithiocarbamate (DDTCNa), which has been widely used as a collector in sulfide mineral flotation  and , has strong chelating reactions with some heavy metals such as Cu, Pb, Co, and Zn to form four-membered ring chelates . Therefore, radially symmetrical may present potential stabilization effect on mobile heavy metals via the generation of sulfide compounds. And compared with the existing dithiocarbamate immobilization agents, DDTCNa is much cheaper and accessible. However, there is little research about its immobilization effect on heavy metals. Thus, the purpose of this study is to evaluate the immobilization effect of DDTCNa on Cu(II) and Zn(II) through column leaching experiments in laboratory, accompanying with the data for sodium sulfide (Na2S) for comparison, and to reveal the immobilization mechanism.
3.3. Formation of ineffective chlorine during chlorination of humic acid
Fig. 3. Formation of ineffective chlorine during the chlorination of humic uk101 solutions with DOC ranged from 0 to 15 mg-C/L (OC: Organic chloramines; initial free chlorine = 5 mg/L as Cl2; chlorination time = 30 min; pH = 7.0, phosphate buffer concentration = 5 mM; temperature = 25 ± 1 °C).Figure optionsDownload full-size imageDownload as PowerPoint slide
3.4. Proportions of ineffective chlorine in different water samples
Fig. 4. Proportions of different chlorine species in water samples collected from (a) DWTP1, (b) TW, (c) DWTP2 and (d) DWTP3 (OC: Organic chloramines, IC: Ineffective chlorine; pH = 7.0, phosphate buffer concentration = 5 mM; temperature = 25 ± 1 °C).Figure optionsDownload full-size imageDownload as PowerPoint slide
3.5. Formation of ineffective chlorine over time in finished water
In this Z-Lys(Z)-OH work different control strategies based on MPC + FF and affine, linear and exponential functions have been tested in a biological wastewater treatment process with the aim of avoiding effluent violations and decreasing EQI and OCI.
The correct variation of the DO set points of the aerated tanks given by the higher level affine function tuned by a trade-off analysis and the tracking of the DO set points by MPC + FF controllers result in a satisfactory EQI and OCI reduction in comparison with the default control strategy. The improvement of the denitrification process, by adding qEC1qEC1, achieves the complete elimination of Ntot,eNtot,e violations. The implemented affine function with a sliding window allows to dosage the minimum qEC1qEC1 necessary for this aim. Finally, the improvement of the nitrification process by manipulating QrinQrin with the combination of a linear function and an exponential function makes possible the NHeNHe violations removal.
The ratios of C-to-N (C/N) was negatively correlated with all CGP-41251 P content parameters (p < 0.05) with the exception of MBP. As one of the important humification parameters, the humification degree increased with decreasing C/N ( Wei et al., 2014a), which may also be combined with increasing levels of TP, IP and AP (Olsen P, WSP and CAP). Significant positive correlations were found between DON and all phosphorus indexes except the proportions of MBP and MAP&NAP ( Table 2). Here, the proportion of MBP had significant correlations with some of the physicochemical and biological parameters during composting. The proportion of MBP in TP was positively correlated with moisture content (MC) (r = 0.431, p < 0.05), C/N (r = 0.402, p < 0.05), organic matter (OM) (r = 0.483, p < 0.01) and NH4–N (r = 0.436, p < 0.05), but it was negatively correlated with germination index (GI) (r = −0.460, p < 0.05). The parameters for dissolved organic carbon (DOC), dissolved organic nitrogen (DON) and the preceding WSP significantly correlated with MBP content ( Fig. 4 and Table 2), suggesting that the movement of dissolved organic matter (DOM) appears to be related to microbial activities.