Synthesis of chlorine dioxide stable solution by combined reduction and its decomposition kinetics

2020 ◽  
Vol 35 (3) ◽  
pp. 342-352
Author(s):  
Minghui Qi ◽  
Lijie Huang ◽  
Xiaofeng Xu ◽  
Tan Yi ◽  
Hao Xu ◽  
...  
Keyword(s):  
Chlorine Dioxide ◽  
Decomposition Rate ◽  
Reduction Method ◽  
Meat Products ◽  
Stable Solution ◽  
Decomposition Kinetics ◽  
World Health ◽  
Fourth Generation ◽  
Dihydrogen Phosphate ◽  
Sodium Dihydrogen Phosphate

AbstractChlorine dioxide is classified by the World Health Organization as a fourth-generation A1, widely used, safe, and effective disinfectant. It is widely used in bleaching, water treatment, oil extraction, aquaculture, plants, fruits and vegetables, meat products, preservation of aquatic products, food sterilization and sterilization industries. The technology of chlorine dioxide produced by the combination reduction method is widely used in domestic papermaking related companies. In order to promote the application of chlorine dioxide, the effects of storage conditions on the stability of chlorine dioxide solution prepared by the combination reduction method and the experimental study of decomposition kinetics were studied. Experiments have shown that high temperature, high pH and high initial concentration accelerate the decomposition of chlorine dioxide solution, and the addition of sodium dihydrogen phosphate (NaH2PO4) and dimethyl sulfoxide (DMSO) can inhibit the decomposition of chlorine dioxide. The kinetic experiments showed that the decomposition rate of chlorine dioxide was secondary to ClO2 and was −0.406 for [{\mathrm{H}^{+}}]. The apparent activation energy of chlorine dioxide solution decomposition reaction was 26.7 kJ·mol−1, and the decomposition rate equation of chlorine dioxide was established.

scholarly journals Pilot-Scale Production of Chito-Oligosaccharides Using an Innovative Recombinant Chitosanase Preparation Approach

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 290
Author(s):  
Chih-Yu Cheng ◽  
Chia-Huang Tsai ◽  
Pei-Jyun Liou ◽  
Chi-Hang Wang
Keyword(s):  
Cell Density ◽  
Scale Up ◽  
Cost Effective ◽  
Pilot Scale ◽  
Ionic Concentration ◽  
Dihydrogen Phosphate ◽  
Scale Production ◽  
Sodium Dihydrogen Phosphate ◽  
Selective Precipitation ◽  
Pilot Scale Production

For pilot-scale production of chito-oligosaccharides, it must be cost-effective to prepare designable recombinant chitosanase. Herein, an efficient method for preparing recombinant Bacillus chitosanase from Escherichia coli by elimination of undesirable substances as a precipitate is proposed. After an optimized culture with IPTG (Isopropyl β-d-1-thiogalactopyranoside) induction, the harvested cells were resuspended, disrupted by sonication, divided by selective precipitation, and stored using the same solution conditions. Several factors involved in these procedures, including ion types, ionic concentration, pH, and bacterial cell density, were examined. The optimal conditions were inferred to be pH = 4.5, 300 mM sodium dihydrogen phosphate, and cell density below 1011 cells/mL. Finally, recombinant chitosanase was purified to >70% homogeneity with an activity recovery and enzyme yield of 90% and 106 mg/L, respectively. When 10 L of 5% chitosan was hydrolyzed with 2500 units of chitosanase at ambient temperature for 72 h, hydrolyzed products having molar masses of 833 ± 222 g/mol with multiple degrees of polymerization (chito-dimer to tetramer) were obtained. This work provided an economical and eco-friendly preparation of recombinant chitosanase to scale up the hydrolysis of chitosan towards tailored oligosaccharides in the near future.

The Effect of Phosphatic Composite on Magnesium Phosphate Cement Performance

2014 ◽  
Vol 809-810 ◽  
pp. 477-484
Author(s):  
Zhao Qing Qi ◽  
Hong Tao Wang ◽  
Jun Liang Dang ◽  
Shi Hao Zhang ◽  
Jian Hua Ding
Keyword(s):  
Setting Time ◽  
Potassium Dihydrogen Phosphate ◽  
Magnesium Phosphate ◽  
Dihydrogen Phosphate ◽  
Ammonium Dihydrogen Phosphate ◽  
Hydrogen Phosphate ◽  
Sodium Dihydrogen Phosphate ◽  
Disodium Hydrogen Phosphate ◽  
Potassium Dihydrogen ◽  
Sodium Dihydrogen

The capacity of 10%, 30%, and 50% ammonium dihydrogen phosphate were replaced with an equal amount of three phosphate (potassium dihydrogen phosphate, sodium dihydrogen phosphate, disodium hydrogen phosphate) respectively. Magnesium phosphate cement was made by phosphate of replaced, which strength, setting time, fluidity, hydration temperature, and the hydration products was researched. The results show that: MPC was made that replaced with the equal amount of three kind of phosphate, which has good mechanical properties. Setting time and fluidity change along with the replacment. Three kind of phosphate replace ammonium dihydrogen phosphate, which change the hydration process of MPC. When ammonium dihydrogen phosphate was replaced by an equal amount of disodium hydrogen phosphate, the temperature of hydration is only 69.4 °C. XRD showed that the diffraction peaks of composite’s magnesium phosphate cement increases.

scholarly journals Sodium Levels of Processed Meat in Australia: Supermarket Survey Data from 2010 to 2017

Nutrients ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1686 ◽  
Author(s):  
Emalie Sparks ◽  
Clare Farrand ◽  
Joseph Santos ◽  
Briar McKenzie ◽  
Kathy Trieu ◽  
...  
Keyword(s):  
Sodium Intake ◽  
Meat Products ◽  
Monitoring And Evaluation ◽  
Sodium Content ◽  
World Health ◽  
Processed Meat ◽  
High Sodium ◽  
Processed Meats ◽  
Health Organization ◽  
Health Dialogue

High sodium intake increases blood pressure and consequently increases the risk of cardiovascular diseases. In Australia, the best estimate of sodium intake is 3840 mg sodium/day, almost double the World Health Organization (WHO) guideline (2000 mg/day), and processed meats contribute approximately 10% of daily sodium intake to the diet. This study assessed the median sodium levels of 2510 processed meat products, including bacon and sausages, available in major Australian supermarkets in 2010, 2013, 2015 and 2017, and assessed changes over time. The median sodium content of processed meats in 2017 was 775 mg/100 g (interquartile range (IQR) 483–1080). There was an 11% reduction in the median sodium level of processed meats for which targets were set under the government’s Food and Health Dialogue (p < 0.001). This includes bacon, ham/cured meat products, sliced luncheon meat and meat with pastry categories. There was no change in processed meats without a target (median difference 6%, p = 0.450). The new targets proposed by the current government’s Healthy Food Partnership capture a larger proportion of products than the Food and Health Dialogue (66% compared to 35%) and a lower proportion of products are at or below the target (35% compared to 54%). These results demonstrate that voluntary government targets can drive nutrient reformulation. Future efforts will require strong government leadership and robust monitoring and evaluation systems.

scholarly journals OFAT versus DOE as two optimization protocols for the chromatographic analysis of some OTC pharmaceuticals carrying negative cardiovascular effects and administered by pregnant and breast-feeding females: Application to dose dependent effect

2020 ◽  
pp. 1-14
Author(s):  
Dina El Sherbiny ◽  
Mary E. K. Wahba
Keyword(s):  
Flow Rate ◽  
Mobile Phase ◽  
Cardiovascular Effects ◽  
Dihydrogen Phosphate ◽  
Sodium Dihydrogen Phosphate ◽  
Pregnancy And Lactation ◽  
Face Centered ◽  
Comparison Of The Results ◽  
Sodium Dihydrogen

Abstract A simple HPLC technique has been utilized for rapid and sensitive quantitative analysis of two mixtures of drugs that are used during pregnancy and lactation. Drugs of the first mixture are used to manage gastrointestinal tract illness that are common during early stages of pregnancy, while pharmaceutical agents of the second mixture are administered over the counter as galactagogues or to overcome postpartum depression. Mixture I includes famotidine (FMT), ranitidine (RNT), nizatidine (NZT), and pantoprazole (PNT), which were separated on a C18 column using a mobile phase composed of methanol: 0.02 M sodium dihydrogen phosphate (60:40, v/v) of pH 6.9, adopting UV detection at 240 nm at a flow rate of 1 mL/min. Mixture II on the other hand, consists of domperidone (DOM), metoclopramide (MET), and sulpiride (SUL). These drugs were eluted using the same column and flow rate as those in mixture I, using a mobile phase consisting of acetonitrile: 0.075 M sodium dihydrogen phosphate (30:70, v/v) of pH 6 adopting a detection wavelength 270 nm. Two optimization protocols were utilized to optimize the chromatographic separation conditions, namely one factor at a time (OFAT) and design of experiments (DOE) where face centered cube response surface experimental design was chosen for this investigation. Comparison of the results obtained from both protocols reveals the accordance between them. Full validation procedure under guidance of United States Pharmacopoeia (USP) was applied to the proposed methods which enabled their application to separate the drugs of both mixtures in spiked rat whole blood samples and in vivo analysis of rat heart blood.

Osmolarity of Human Serum and of Chemical Solutions of Biologic Importance

1961 ◽  
Vol 7 (2) ◽  
pp. 156-164 ◽  
Author(s):  
Edward B Hendry
Keyword(s):  
Human Serum ◽  
Freezing Point ◽  
Potassium Dihydrogen Phosphate ◽  
Dihydrogen Phosphate ◽  
Hydrogen Phosphate ◽  
Sodium Dihydrogen Phosphate ◽  
Disodium Hydrogen Phosphate ◽  
Normal Human ◽  
Chemical Solutions ◽  
Sodium Dihydrogen

Abstract With the use of the Fiske Osmometer, the mean total osmolarity of normal human serum was found to be 289 mOsM (S.D., 4), which is equivalent to a mean freezing point of -0.537°. The isosmotic concentrations of some important biologic solutions were determined. It was also found that M/15 solutions of disodium hydrogen phosphate and of potassium dihydrogen phosphate are very hypotonic, and that 3.8% sodium citrate is hypertonic. Hemolysis of erythrocytes in isosmotic ammonium chloride solution can be considerably delayed by the addition of 3.0% glucose to the solution. Isosmotic concentrations of disodium hydrogen phosphate and sodium dihydrogen phosphate were precisely determined, as were pH levels of buffer solutions made from these two salts. The cause of the slight changes in osmolarity that occur when these two isosmotic solutions are mixed is discussed.

Liquid Chromatographic Determination of Fumonisins with 4-Fluoro-7-nitrobenzofurazan

1992 ◽  
Vol 75 (5) ◽  
pp. 829-833 ◽  
Author(s):  
Peter M Scott ◽  
Guillaume A Lawrence
Keyword(s):  
Limit Of Detection ◽  
Potassium Cyanide ◽  
Chromatographic Determination ◽  
Reversed Phase ◽  
Dihydrogen Phosphate ◽  
Corn Meal ◽  
Sodium Dihydrogen Phosphate ◽  
Corn Flakes ◽  
Ground Corn ◽  
Fumonisins B1 And B2

Abstract Fumonisins B1 and B2 are closely related mycotoxins produced by Fusarium moniliforme, F. proliferatum, and related species. Disadvantages of 2 fluorescence derivatizing reagents currently used for liquid chromatography (LC) are instability of the derivatives (with o-phthaldialdehyde-mercaptoethanol) and formation of 2 peaks (with fluorescamine). 4-Fluoro-7-nitrobenzofurazan (4-fluoro-7- nitrobenz-2-oxa-1,3-diazole; NBD-F) was, therefore, investigated. Although a larger molar excess of this reagent is required for fumonisins than for amino acids, the derivatives formed are moderately stable, and as little as 1 ng fumonisins B1 or B2 can be detected, with a linear response up to at least 50 ng injected. Reversed-phase LC (C18 column) was carried out with a mobile phase of methanol- 0.05M sodium dihydrogen phosphate adjusted to pH 5 (1 -1-1), which was mixed with an equal volume of acetonitrile-water (8 + 2) after 5 min. Using a modification of a strong anion exchange cleanup procedure, good recoveries (averages of 94 and 80%, respectively) of fumonisins B1 and B2 from ground corn, corn meal, and corn flakes in the 125̶ 5000 ng/g range were generally obtained; the limit of detection of the overall method was about100 ng/g. Similar results were obtained in studies with ground corn, corn meal, and corn flakes using naphthalene-2,3-dicarboxaldehyde-potassium cyanide (NDA-KCN) for derivatization; average recoveries of fumonisins B1 and B2 were 94 and 83%, respectively.

The Discharge Characteristics of PEO Films in K2ZrF6 with NaH2PO4 Electrolyte

2012 ◽  
Vol 577 ◽  
pp. 115-118
Author(s):  
Wen Fu ◽  
Li Wang ◽  
Li Chen
Keyword(s):  
Oxidation Process ◽  
Dihydrogen Phosphate ◽  
Sodium Dihydrogen Phosphate ◽  
Discharge Characteristics ◽  
Effect Of Additives ◽  
Ceramic Films ◽  
Electrolytic Oxidation ◽  
Plasma Electrolytic ◽  
Different Content ◽  
Sodium Dihydrogen

The discharge characteristics of the potassium fluorozirconate electrolyte during plasma electrolytic oxidation process were investigated. Sodium dihydrogen phosphate was applied as additives. Ceramic films were prepared on magnesium alloy in electrolytes with different content additives under constant voltage. The effect of additives on the pH of the electrolyte and the dissolution of the substrate were investigated. It was found that the additives could influence the pH and dissolved magnesium ions effectively.

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