New insight on the combined effects of hydrothermal treatment and FeSO4/Ca(ClO)2 oxidation for sludge dewaterability improvement: From experimental to theoretical investigation

In this theoretical investigation, we have examined the combined effects of nonthermally revamped polarization force on modulational instability MI of dust acoustic waves DAWs and evolution of different kinds of dust acoustic (DA) breathers in a dusty plasma consisting of negatively charged dust as fluid, Maxwellian electrons, and ions obeying Cairns’ nonthermal distribution. The nonthermality of ions has considerably altered the strength of polarization force. By employing the multiple-scale perturbation technique, the nonlinear Schrödinger equation NLSE is derived to study modulational MI instability of dust acoustic waves DAWs. It is noticed that influence of the polarization force makes the wave number domain narrow where MI sets in. The rational solutions of nonlinear Schrödinger equation illustrate the evolution of DA breathers, namely, Akhmediev breather, Kuznetsov–Ma breather, and Peregrine solitons (rogue waves). Further, the formation of super rogue waves due to nonlinear superposition of DA triplets rogue waves is also discussed. It is analyzed that combined effects of variation in the polarization force and nonthermality of ions have a comprehensive influence on the evolution of different kinds of DA breathers. It is remarked that outcome of present theoretical investigation may provide physical insight into understanding the role of nonlinear phenomena for the generation of various types of DA breathers in experiments and different regions of space (e.g., the planetary spoke and cometary tails).

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Influence of Persulfate on Transformation of Phosphorus and Heavy Metals for Improving Sewage Sludge Dewaterability by Hydrothermal Treatment

10.21203/rs.3.rs-431772/v1 ◽

2021 ◽

Author(s):

Qiao Xiong ◽

Jing Xia ◽

Xiang Wu ◽

Xu Wu ◽

Haobo Hou ◽

...

Keyword(s):

Heavy Metals ◽

Sewage Sludge ◽

Hydrothermal Treatment ◽

Hydrothermal Process ◽

Treatment Technique ◽

Capillary Suction ◽

Hydrothermal Temperature ◽

Persulfate Oxidation ◽

Sludge Dewaterability ◽

Temperature Time

Abstract Activated persulfate oxidation has been proven to be an efficient advanced sludge treatment technique to improve sludge dewaterability. This study investigates the influence of persulfate on the transformation of phosphorus (P) and heavy metals (HMs) during the hydrothermal treatment of sewage sludge. The hydrothermal temperature, time, and persulfate concentration are optimized by a Box-Behnken design to obtain the best sludge dewaterability, which is expressed by capillary suction time (CST). The highest CST reduction efficiency is 90.5% at the optimal hydrothermal temperature, time and concentration of persulfate, which are 145 °C, 2 h, and 150 mg/g DS, respectively. The distribution and transformation of P and HMs with different persulfate concentrations (100-200 mg/g DS) during the hydrothermal process are investigated. Results show that more than 90% of the P and HMs in the sludge are retained in sludge cakes after the hydrothermal treatment. The addition of SPS can make the P in the sludge cakes transform into more stable P species according to the extraction capacity of sequential extracts. It can be found from the ecological risk indexes of the HMs that the addition of SPS during the hydrothermal treatment of sludge can reduce the environmental risk of HMs. This study provides insights into the P and HM distribution and transformation during hydrothermal treatment with persulfate, providing a reference for sludge recovery strategies.

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Fe(II)-activated sodium percarbonate for improving sludge dewaterability: Experimental and theoretical investigation combined with the evaluation of subsequent utilization

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.149382 ◽

2021 ◽

pp. 149382

Author(s):

Xiao Ling ◽

Jing Deng ◽

Cheng Ye ◽

Anhong Cai ◽

Shuyu Ruan ◽

...

Keyword(s):

Theoretical Investigation ◽

Sodium Percarbonate ◽

Sludge Dewaterability

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Effects of Retinoic Acid and 1,25-Dihydroxyvitamin D3 on IFN-gamma Secretion by Mononuclear Leukocytes from Nulliparous and Postparturient Dairy Cattle

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831.70.3.92 ◽

2000 ◽

Vol 70 (3) ◽

pp. 92-101 ◽

Cited By ~ 14

Author(s):

Burim Ametaj ◽

Brian Nonnecke ◽

Ronald Horst ◽

Donald Beitz

Keyword(s):

Retinoic Acid ◽

Dairy Cattle ◽

Dairy Cows ◽

Dairy Cow ◽

Pokeweed Mitogen ◽

Mononuclear Leukocytes ◽

Combined Effects ◽

Ifn Gamma ◽

Dihydroxyvitamin D ◽

1,25 Dihydroxyvitamin D

Individual and combined effects of several isomers of retinoic acid (RA) and 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) on interferon-gamma (IFN-gamma) secretion by blood mononuclear leukocytes (MNL) from nulliparous and postparturient Holstein cattle were evaluated in vitro. In the first experiment, effects on incubation period (24 to 72 hours) and time of supplementation (0 to 32 hours) with all-trans, 9-cis, 13-cis-, and 9,13-dicis-RAs (0 to 100 nM) on IFN-gamma secretion by pokeweed mitogen (PWM)-stimulated (0 and 10 mug/ml) MNL from nulliparous cattle were evaluated. In the second experiment, MNL from postparturient cows (bled at 0, 2, 4, and 16 days postpartum) were stimulated with PWM (0 and 10 mug/ml) in the presence of RA isomers (9-cis- or 9,13-dicis-RA; 0 to 100 nM), 1,25-(OH)2D3 (0 to 100 nM), or with combinations of these metabolites. The results show that individual isomers of RA had no effect on IFN-gamma secretion by PWM-stimulated MNL from nulliparous or postparturient cows. Furthermore 1,25-dihydroxyvitamin D3 inhibited IFN-gamma secretion by MNL from nulliparous and postparturient dairy cows; however, the degree of inhibition was greater when 9-cis- and 9,13-dicis-RA were also present in the cultures. Finally mononuclear leukocytes from postparturient dairy cows produced substantially less IFN-gamma than did MNL from nulliparous cattle. It is concluded that retinoic acids individually did not affect the capacity of leukocytes from dairy cattle to secrete IFN-gamma. This result is in marked contrast to studies in monogastric species indicating that RAs inhibit IFN-gamma secretion by peripheral blood T cells. Inhibition of IFN-gamma secretion by 1,25-(OH)2D3 was potentiated by 9-cis- and 9,13-di-cis-retinoics acids, suggesting that an excess of dietary vitamins A and D may compromise further the naturally immunosuppressed postparturient dairy cow. Additional research is necessary to determine if the combined effects of these metabolites on IFN-gamma secretion represent an increased susceptibility of the dairy cow to infectious diseases during the periparturient period. Lower secretion of IFN-gamma by MNL from postpartutient dairy cows, relative to nulliparous cattle, suggests that recently-calved cows are naturally immunosuppressed.

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