Preparation and application of an innovative integrated agent product for phosphorus control and oxygen release

Abstract In this study, an oxygen-releasing and phosphorus-controlling agent (ORPC) consisting of calcium peroxide (CaO2), bentonite, cement, stearic acid (SA), citric acid (CA) and fine sand was synthesized successfully and used to purify rich-phosphorus river water. The removal of phosphorus using ORPC was studied in actual river water and the results found that over 75.0% phosphorus was removed by adding ORPC at 30 mL h−1 flow rate in the initial phosphorus concentrations of 0.76 mg L−1. The ORPC was further used to evaluate the changes of aluminum phosphate (Al-P), ferric phosphate (Fe-P) and calcium phosphate (Ca-P) in sediment. Fe-P, Al-P, and Ca-P in the sediment increased from 0.14, 0.196, and 1.63 mg g−1 to 0.159, 0.372, and 2.74 mg g−1 respectively within 28 days, indicating that the total dissolved phosphorus in the overlying water could be adsorbed by ORPC and further transformed into Al-P, Ca-P, and Fe-P in the sediment, thus inhibiting the release of endogenous phosphorus in sediment to water. Besides, the performance of ORPC with various contents of SA and CaO2 was investigated. In summary, ORPC can be employed to adsorb phosphorus in water and prevent phosphorus release from sediment, therefore achieving the purpose of controlling phosphorus and maintaining DO at a reasonable level.

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Phosphorus Release Processes in Nearshore Southern Lake Michigan

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f86-149 ◽

1986 ◽

Vol 43 (6) ◽

pp. 1201-1207 ◽

Cited By ~ 17

Author(s):

Michael A. Quigley ◽

John A. Robbins

Keyword(s):

Pore Water ◽

Lake Michigan ◽

Sampling Site ◽

Soluble Reactive Phosphorus ◽

Fine Sand ◽

Phosphorus Release ◽

Fickian Diffusion ◽

Phosphorus Cycle ◽

Release Rates ◽

Overlying Water

We determined soluble reactive phosphorus (SRP) release rates from intact, medium-fine sand cores obtained from an 11-m-deep sampling site in nearshore Lake Michigan during July–October 1980. Mean SRP release ranged from 0.17 ± 0.03 (SE) to 0.57 ± 0.04 mg PO4-P∙m−2∙d−1. Pore water analysis indicated that, despite high dissolved oxygen concentrations in the uppermost 6 cm of sediment, SRP concentrations increased rapidly with depth throughout this zone. Moreover, a Fickian diffusion equation based on the SRP pore water gradient and physical sediment features predicted a release rate (1.12 mg PO4-P∙m−1∙d−1) that was 2–7 times higher than release rates measured from intact cores. Results suggest that nearshore sediments provide a ready pathway for the return of SRP to overlying water, and this process warrants inclusion in future conceptual models of Lake Michigan's phosphorus cycle.

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Numerical Simulation of Phosphorus Release with Sediment Suspension under Hydrodynamic Condition in Mochou Lake, China

Water ◽

10.3390/w11020370 ◽

2019 ◽

Vol 11 (2) ◽

pp. 370 ◽

Cited By ~ 1

Author(s):

Yu Bai ◽

Jinhua Gao ◽

Tianyi Zhang

Keyword(s):

Lattice Boltzmann ◽

Phosphorus Release ◽

Hydrodynamic Condition ◽

Sediment Suspension ◽

Hydrodynamic Conditions ◽

Lake Water Quality ◽

Overlying Water ◽

Dissolved Phosphorus ◽

Experimental Process ◽

Boltzmann Method

Phosphorus is a major cause of lake eutrophication. Understanding the characteristics regarding the release of phosphorus from sediments under hydrodynamic conditions is critical for the regulation of lake water quality. In this work, the effects of sediment suspension on the release characteristics of phosphorus from sediment were investigated under different hydrodynamic conditions. The experimental results showed that in the experimental process, the phosphorus was at first released quickly into the overlying water but then slowed down. Furthermore, the process of dissolved phosphorus (DP) release under hydrodynamic conditions with and without sediment suspension was simulated using a lattice Boltzmann method. The simulation showed satisfying results.

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Development of A Nano-Apatite Based Composite Sealer for Endodontic Root Canal Filling

Journal of Composites Science ◽

10.3390/jcs5010030 ◽

2021 ◽

Vol 5 (1) ◽

pp. 30

Author(s):

Angelica Bertacci ◽

Daniele Moro ◽

Gianfranco Ulian ◽

Giovanni Valdrè

Keyword(s):

Citric Acid ◽

Liquid Phase ◽

Calcium Phosphate ◽

Root Canal ◽

Acid Attack ◽

Root Canal Filling ◽

Bioactive Materials ◽

Dentinal Tubules ◽

Sealing Capacity ◽

Endodontic Sealers

Recently, endodontic sealers based on injectable bioactive materials were proposed to improve the filling of anatomical irregularities during root canal obturation. In this context, this preliminary work investigated the possibility of realizing a new calcium phosphate-based composite sealer for root canal filling with an optimized composition on setting kinetics and dentin tubules occlusion. Several calcium phosphate/liquid phase mixtures were initially evaluated for their workability, finding two suitable formulations. Both of them contained 66 wt.% of a nano-apatite-based cement (solid powdered phase). The liquid phase (34 wt.%) comprised 13.6% propanediol and 20.4% PEG 1000 (formulation 1), and formulation 2 comprised 27.2% glycerin and 6.8% PEG 200 (formulation 2). Then, these formulations were tested by means of permeability measurements and observation by scanning electron microscopy of treated model dentin samples. Both formulations succeeded in occluding dentinal tubules: the first one was able to create a full-bodied layer on dentin surface and, moreover, to resist, at least to a large extent, against citric acid attack. The second one showed a lower effectiveness after citric acid exposure. The composite compound that better satisfied the overall required characteristics of use, workability and sealing capacity was formulation 1.

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Phytase and Citric Acid Supplementation in Whole-Wheat Bread Improves Phytate-phosphorus Release and Iron Dialyzability

Journal of Food Science ◽

10.1111/j.1365-2621.2001.tb04610.x ◽

2001 ◽

Vol 66 (4) ◽

pp. 614-619 ◽

Cited By ~ 39

Author(s):

J.M. Porres ◽

P. Etcheverry ◽

D.D. Miller ◽

X.G. Lei

Keyword(s):

Citric Acid ◽

Phosphorus Release ◽

Wheat Bread ◽

Acid Supplementation ◽

Whole Wheat ◽

Phytate Phosphorus ◽

Whole Wheat Bread

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Comparison of potassium citrate, citric acid and placebo on calcium phosphate stones recurrence: Preliminary results

European Urology Supplements ◽

10.1016/s1569-9056(18)31156-4 ◽

2018 ◽

Vol 17 (2) ◽

pp. e439-e440

Author(s):

S. Doizi ◽

J. Poindexter ◽

M. Pearle ◽

K. Sakhaee ◽

N. Maalouf

Keyword(s):

Citric Acid ◽

Calcium Phosphate ◽

Potassium Citrate ◽

Preliminary Results

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Enhanced Phosphorus Release from Phosphate Rock Activated with Lignite by Mechanical Microcrystallization: Effects of Several Typical Grinding Parameters

Sustainability ◽

10.3390/su11041068 ◽

2019 ◽

Vol 11 (4) ◽

pp. 1068

Author(s):

Xian-mei Zhang ◽

Yi Li ◽

Cheng Hu ◽

Zhen-quan He ◽

Ming-xing Wen ◽

...

Keyword(s):

Citric Acid ◽

Phosphate Rock ◽

Phosphorus Release ◽

The Sustainable Development ◽

Enhanced Dissolution ◽

Granule Morphology ◽

Soluble P ◽

The Relationship ◽

Direct Use ◽

Activation Property

Recently, microcrystallization technology has gained much interest because of the enhanced dissolution of the target sample and promotion of the sustainable development of agriculture. Phosphorus (P) is one of the most important nutrients for increasing crop yield; the increase in effective P ratio directly from raw phosphate rock (PR) powder by mechanical grinding to increase its microcrystallinity is believed to be the best choice for this purpose. This study reports the improvement in the activation property of PR powder with different lignite ratios (1%, 2%, 3%, and 5%), particularly the relationship between particle-size distribution, specific surface area, granule morphology, and the citric acid-soluble P. It was found that a 3% lignite addition was the optimal treatment for increasing the release of citric acid-soluble P. The maximum total amount of dry matter from rapeseed cultivation and the available P after the test increased by 56.1% and 89.6%, respectively, with direct use of PR and microcrystallized PR powder (PR2), compared with the control test without any addition of phosphate minerals.

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Feeding behavior of the cirratulid Cirriformia filigera (Delle Chiaje, 1825) (Annelida: Polychaeta)

Brazilian Journal of Biology ◽

10.1590/s1519-69842004000200014 ◽

2004 ◽

Vol 64 (2) ◽

pp. 283-288 ◽

Cited By ~ 5

Author(s):

E. V. Pardo ◽

A. C. Z. Amaral

Keyword(s):

Feeding Behavior ◽

Substrate Surface ◽

Fine Sand ◽

Middle Part ◽

Sediment Surface ◽

Ventral Region ◽

Overlying Water ◽

Shaped Tube ◽

Food Particles ◽

Made In

Observations of the feeding behavior of Cirriformia filigera (Delle Chiaje, 1825) (Annelida: Polychaeta) from the intertidal zone of São Francisco and Engenho D'água beaches (São Sebastião, State of São Paulo) were made in the laboratory. This species, like other cirratulids, is a deposit feeder, feeding mainly on sediment surface with the aid of its grooved and ciliated palps, which are used to capture food particles. The worm lies just beneath the substrate surface in a J-shaped tube. When feeding, it extends up to 4 palps over the sediment surface, capturing food particles which pass down the groove of each palp directly to the mouth. Only fine sand grains are ingested. The worm frequently extends 4 branchial filaments into the overlying water for aeration. When it moves with the prostomium sideways, it collects and transports sand grains that pass backwards along its ventral region until reaching the middle part of its body. Next, the parapodia and palps move the sand grains to the dorsal posterior end of the animal, covering this area with sand. Some sand grains are also ingested as the worm moves.

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Electrophoretic Deposition of Green Parts for LPS SiC-Based Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.314.45 ◽

2006 ◽

Vol 314 ◽

pp. 45-50 ◽

Cited By ~ 3

Author(s):

Saša Novak ◽

Goran Dražič ◽

Katja Mejak

Keyword(s):

Silicon Carbide ◽

Citric Acid ◽

Liquid Phase ◽

Deposition Rate ◽

Electrophoretic Deposition ◽

Aluminum Phosphate ◽

Sintering Additives ◽

Solids Loading ◽

Solids Content

Electrophoretic deposition of silicon carbide in ethanol suspensions was studied with the aim to fabricate liquid-phase sintered (LPS) SiC-based ceramics densified at temperatures below 1500°C. The effect of suspensions composition (solids content, pH, sintering additives) on the deposition rate and the properties of the deposits was analysed. The consistency of deposits and their solids loading was found to be significantly dependent on composition of the starting suspension: the highest solids loading (54.5 vol. %) for pure SiC was obtained with the addition of citric acid, while for the suspension containing aluminum phosphate the deposition was more successful from alkaline suspensions.

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