Fig. 15. Local equivalence ratio, flow velocity level lines and gas temperature profiles along Ezatiostat half height of channel with cavities (2.5 mm ? y ? 4.0 mm) for different longitudinal distance of the quartz combustor at ? = 0.5: (a) local equivalence ratio profiles; (b) flow velocity level lines; (c) gas temperature profiles.Figure optionsDownload full-size imageDownload as PowerPoint slide
AcknowledgementsThis work was supported by the Natural Science Foundation of China (No. 51276073) and the Foundation of State Key Laboratory of Coal Combustion, China (Grant No. FSKLCCA1503).
Nickel carbide; Ni nanoparticles; Carbon nanofibers; Catalytic chemical vapor deposition; Hydrogenation
As one of important carbon nanomaterials, carbon nanofibers (CNFs) have attracted increasing attention because of their unique physicochemical properties including high mechanical strength, good electrical conductivity, unique surface properties, high resistance to acid/basic media and good accessibility of the active phase, which make them suitable as heterogeneous catalyst supports , , ,  and . As catalyst supports, CNFs especially can induce an electronic perturbation to metal crystallites in liquid phase reaction, which greatly modifies the catalytic performance . Undoubtedly, efficient immobilization of guest components through surface modification of CNFs is essential for enhancing the interactions between supports and catalytically active species and thus achieving excellent catalytic performance.
Fig. 12 illustrates the concentration of Compound 56 over the time period of experiments. Ozone concentration is very low at a voltage level of 17 kVPP, regardless of the applied repetition rates, which implies no ozone production by NTP at these levels. When the applied voltage approaches 17 kVPP, ozone concentration increases significantly for all repetition rates. The ozone concentration at 17 kVPP is almost constant over the period of study for 2.5 and 5 kHz. However, it increases slightly at 7.5 kHz and more significantly at 10 kHz. For 19 kVPP, ozone concentration increases at 2.5, 5 and 7.5 kHz with different gradients over the period of study. On the other hand, in the same period of time, ozone concentration has been decreased continuously at 19 kVPP and 10 kHz. This trend is in contrast with the PM concentrating trend obtained from Fig. 11 at the same operating points. Thus, decreasing the ozone concentration, a lesser amount of PM can be removed by the DBD plasma reactor at this state. The same trade-off can be observed between ozone and PM at 21 kVPP for repetition rates of 7.5 and 10 kHz as well. Furthermore, as can be observed in Fig. 10, CO2 concentration at 21 kVPP and 10 kHz will be constant and even increase to some extent at the end of the time period of the experiment. This can be due to the reduction of ozone and also PM oxidation at this state. Therefore, ozone is found to be a key parameter for PM removal from diesel exhaust gas, which should be considered in all plasma emission treatment applications.
Tetrahydrofuran (THF), a well-known thermodynamic hydrate promoter, can be added to the system in order to significantly reduce the equilibrium pressure for gas hydrate formation at a specified temperature , , , , , ,  and . However, THF has several drawbacks for its actual usage in the process, because it is highly volatile and toxic  and . THF can be entrained and mixed with gas mixtures retrieved from the gas hydrate phase after dissociation, indicating that further processes for purification of the gas phase, and for recovery of THF, might be needed.
Since WWTPs can remove IBP from waters with inadequate efficiency, new research efforts are currently being made to find novel and efficient treatments to be integrated within the WWTP schemes. A first line of activities includes the transformation of IBP into harmless compounds through photocatalysis , Chemical Atazanavir , Fenton processes  and , ozonation , sonochemical degradation  and cavitation . All these applications have been put forward only recently and, even if the results are promising, there is still some uncertainty at the genesis of degradation compounds and by-products, which should be further investigated. In order to overcome this drawback and to work out an effective depuration technology, a second line of investigation refers to the application of adsorption processes, mainly conducted on either natural materials  or activated carbons , ,  and .
Adsorption has been widely used for water, groundwater or wastewater treatment, because endothermic combines good efficiencies with a reliable and robust process configuration  and . It is a very versatile process that can be used for organic compounds and heavy metal capture thanks to a wide spectrum of adsorption targets ,  and  as well as for single or multiple contaminations  and . The wide application of the adsorption process is also due to the possibility of using different kinds of adsorbents, including natural and waste materials either raw or activated , ,  and .
The objectives of this study are (1) to compare different reduction reagents used as quenchers for total chlorine, (2) to optimize the quenching condition for ineffective chlorine determination using NaAsO2, (3) to examine the formation of ineffective chlorine during chlorination of Suwanne River humic Sulfo-NHS-LC-Biotin and in finished waters from DWTPs, and (4) to investigate the sterilization efficacy of ineffective chlorine by comparing with other residual chlorine species.
2. Materials and methods
All reagents used were at least of analytical grade. Sodium hypochlorite (NaOCl, 4–4.99%), ammonium chloride (NH4Cl, ?99.5%), DPD sulfate (?99.0%), potassium iodide (KI, ?99.0%), potassium phosphate monobasic (KH2PO4, ?99.0%) and sodium phosphate dibasic (Na2HPO4, ?99.0%) were all purchased from Sigma–Aldrich (USA). Suwannee River humic acid (standard II) was purchased from International Humic Substances Society (IHSS, USA). Other chemicals including sodium sulfite (Na2SO3), sodium hydrogen sulfite (NaHSO3), sodium thiosulfate (Na2S2O3), sodium arsenite (NaAsO2) and ascorbic acid were obtained from Sinopharm Chemical Reagent Co., Ltd. (China) without further purification. All solutions were prepared using ultrapure water produced from a Milli-Q water purification system (Millipore, USA) with total chlorine content under the method detection limit (MDL).
2.4. Quantitative analysis of microbial cluster size
Fifty microliter mixed sludge medium were collected from each reactor at 0, 3, 9, 12, and 24 h after inoculation, respectively, and were then analyzed. We employed 3-Deazaneplanocin A optical microscope system (Olympus BX41, Japan) to analyze microbial clusters sizes via image acquisition, and ten slides of each sample were recorded for size analysis. Microbial cluster size was represented by its projected area on the slide  and .
2.5. Extraction and analysis of EPS
2.6. Surface charge
The surface charge of microbial clusters was determined using colloid titration modified from Mikkelsen . Polybrene and polyvinyl sulfate potassium salt (PVSK) were used as positive and negative colloidal reagents, respectively. First, 5.0 mL of 0.001 N polybrene was added to 100.0 mL diluted sample (containing 1.0 mL mixed sludge). The excess polybrene was back titrated with 0.0005 N PVSK to a community simplification colourimetric endpoint indicated by toluidine blue. Equal volumes of polybrene in centrifuged supernatant without microbial clusters were used as blanks.
Acetone is a polar solvent with an electronegative carbonyl group. This carbonyl group disrupts hydrogen bonds in GW788388 and causes protein denaturation. Therefore, when acetone was applied to the aerobic granules, it reacted with cellular proteins and the EPS. As a result, the EPS proteins were denatured and removed. However, acetone was only able to disrupt the tertiary bonds of the protein; the primary bonds of the protein remained intact (Simpson and Beynon, 2009). This could be a likely reason for the incomplete removal of the EPS.
3.2.4. Sodium chloride
3.3. EPS removal – PHA dissolving step
3.4. PHA recovery
Fig. 3(a) shows the amounts of recovered PHA from aerobic granules using three different volumes of sodium hypochlorite. The highest PHA recovery yield was 89% of the cell dry weight (CDW) and was observed when using 12.5 mL of NaOCl. As complete removal of EPS was observed for NaOCl method, guanine is postulated that all PHA has been extracted out from aerobic granules by using 12.5 mL of NaOCl. Based on this PHA recovery yield, it can be inferred that aerobic granules possesses high capacity in accumulating PHA. It matches the highest PHA yield in mixed culture that has been reported to date (Johnson et al., 2009).