Die Cyanat-induzierte Umwandlung von Calciumhydrogenphosphat in Calciumdiphosphat -eine präbiotische Schlüsselreaktion ? / The Conversion of Calcium Hydrogenphosphate into Calcium Diphosphate by Cyanate - a Prebiotic Key Reaction ?

1978 ◽  
Vol 33 (8) ◽  
pp. 873-876 ◽  
Author(s):  
F. Seel ◽  
F. Schinnerling
Keyword(s):  
Calcium Phosphate ◽  
Aqueous Suspension ◽  
Prebiotic Synthesis ◽  
Photochemical Oxidation ◽  
Hydrocyanic Acid ◽  
Dihydrogen Phosphate ◽  
Hydrogen Phosphate

Abstract The conversion of calcium phosphate into calcium diphosphate through cyanate in an aqueous suspension, discovered by Miller and Parris [1], has been reinvestigated thor-oughly. The reaction is initiated through the disproportionation of calcium hydrogen phosphate to give hydroxylapatite and calcium dihydrogen phosphate, which reacts with cyanate via carbamoylphosphate to yield calcium diphosphate and urea. In particular, it could be shown that the process of phosphate condensation may also be initiated when cyanate is generated by a photochemical oxidation of hydrocyanic acid. -The importance of this reaction with respect to the prebiotic synthesis of biopolymers is discussed.

Note on the loss of phosphoric acid during fusion with ammonium fluoride

1916 ◽  
Vol 8 (1) ◽  
pp. 136-138
Author(s):  
William A. Davis ◽  
James Arthur Prescott
Keyword(s):  
Calcium Phosphate ◽  
Alkali Metal ◽  
Phosphoric Acid ◽  
Potassium Dihydrogen Phosphate ◽  
Ammonium Fluoride ◽  
Dihydrogen Phosphate ◽  
Hydrogen Phosphate ◽  
Disodium Hydrogen Phosphate ◽  
Potassium Dihydrogen ◽  
Considerable Loss

1. When salts or minerals containing phosphoric acid are ignited with ammonium fluoride as in the ordinary process of analysis of silicates, considerable loss of the phosphoric acid may occur. It is probable that the phosphorus is volatilised in the form of a phosphorus fluoride.2. The loss is least in the case of salts containing an alkali metal. It is less in the case of disodium hydrogen phosphate than in that of potassium dihydrogen phosphate, and is greatest in the case of phosphates of the alkali earth metals, such as calcium phosphate or apatite.

scholarly journals A Study on the Thermal Properties of Dibasic Calcium Hydrogen Phosphate and Monobasic Calcium Phosphate.

1997 ◽  
Vol 13 (Supplement) ◽  
pp. 413-418 ◽  
Author(s):  
Li-Kuo Lin ◽  
Jinn-Shing Lee ◽  
Chung-King Hsu ◽  
Paou-fang Huang ◽  
Hsiao-Tsung Lin
Keyword(s):  
Thermal Properties ◽  
Calcium Phosphate ◽  
Hydrogen Phosphate ◽  
Monobasic Calcium Phosphate

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 The enantioselective β-keto ester reductions by Saccharomyces cerevisiae

2006 ◽  
Vol 71 (8-9) ◽  
pp. 889-894 ◽  
Author(s):  
Nosrat Mahmoodi ◽  
Hassan Tajik ◽  
Khalil Tabatabaeian ◽  
Mahmood Shahbazi
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Calcium Phosphate ◽  
Potassium Dihydrogen Phosphate ◽  
Dihydrogen Phosphate ◽  
Ammonium Tartrate ◽  
Potassium Dihydrogen ◽  
Keto Ester ◽  
Keto Esters ◽  
Diammonium Salt ◽  
Hydroxy Esters

The enantioselective yeast reduction of aromatic ?-keto esters, by use of potassium dihydrogen phosphate, calcium phosphate (monobasic), magnesium sulfate and ammonium tartrate (diammonium salt) (10:1:1:50) in water at pH7 as a buffer for 72-120h with 45-90 % conversion to the corresponding aromatic ?-hydroxy esters was achieved by means of Saccharomyces cerevisiae.

scholarly journals CAPILLARY ELECTROPHORETIC ANALYSIS OF LOW-MOLECULAR-MASS OF CA SPECIES IN PHLOEM SAP OF Ricinus communis L.

2010 ◽  
Vol 6 (2) ◽  
pp. 181-185 ◽  
Author(s):  
Noor Fitri ◽  
Björn Thiele ◽  
Klaus Günther ◽  
Buchari Buchari
Keyword(s):  
Molecular Mass ◽  
Ricinus Communis ◽  
Ultra Violet ◽  
Electrophoretic Analysis ◽  
Active Species ◽  
Dihydrogen Phosphate ◽  
Hydrogen Phosphate ◽  
Phloem Sap ◽  
Ricinus Communis L ◽  
Capillary Electrophoretic

A capillary electrophoretic (CE) analysis with ultra-violet (UV) detection was performed for further separation of low-molecular-mass (LMM) calcium species in phloem sap of Ricinus communis L. Two different background electrolytes (BGE) were used for the separation; these are (1) hydrogen phosphate/dihydrogen phosphate buffer containing cetyltrimethylammonium bromide (CTAB) as an electro-osmotic flow (EOF) modifier, and (2) boric acid buffer containing CTAB. Various parameters affecting the analysis, including the composition and pH of the BGE were systematically studied. The sensitivity, resolution, baseline noise, migration time of the species peaks, and reproducibility of the method were evaluated under optimised condition. At least 13 UV-active species were optimally separated within about ten minutes. The optimised measurement condition was also achieved using 10 mM hydrogen phosphate/10 mM dihydrogen phosphate containing 0.5 mM CTAB at pH 8.0 as BGE, and by applying voltage of ‑20 kV and temperature of 14°C. Evidently, the analytical method was successfully used for the separation of LMM calcium species in phloem sap of R. communis L.   Keywords: capillary electrophoresis, calcium species, phloem sap, Ricinus communis

scholarly journals Hydrogen Phosphate Selectively Induces MDA-MB-231 Breast Cancer Cell Death in vitro

2021 ◽  
Author(s):  
Aya Shanti ◽  
Kenana Al Adem ◽  
Cesare Stefanini ◽  
Sungmun Lee
Keyword(s):  
Breast Cancer ◽  
Cell Death ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Dihydrogen Phosphate ◽  
Human Breast ◽  
Hydrogen Phosphate ◽  
Cancer Cell Death ◽  
Phosphate Ions

Abstract Phosphate ions are the most abundant anions inside the cells, and they are increasingly gaining attention as key modulators of cellular function and gene expression. However, little is known about the effect of inorganic phosphate ions on cancer cells, particularly breast cancer cells. Here, we investigated the toxicity of different phosphate compounds to triple-negative human breast cancer cells (MDA-MB-231) and compared it to that of human monocytes (THP-1). We found that, unlike dihydrogen phosphate (H2PO4−), hydrogen phosphate (HPO42−) at 20 mM or lower concentrations induced breast cancer (MDA-MB-231) cell death more than immune (THP-1) cell death. We correlate this effect to the fact that phosphate in the form of HPO42− raises pH levels to alkaline levels which are not optimum for transport of phosphate into cancer cells. The results in this study highlight the importance of further exploring hydrogen phosphate (HPO42−) as a potential therapeutic for the treatment of breast cancer.

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.

scholarly journals Existing form and distribution of fluorine and phosphorus in phosphate rock acid-insoluble residue

2021 ◽  
Author(s):  
Rui Li ◽  
Wei Long He ◽  
Jiangfei Duan ◽  
Shengxia Feng ◽  
Ziyu Zhu ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Phosphate Rock ◽  
Insoluble Residue ◽  
Metal Fluoride ◽  
Dihydrogen Phosphate ◽  
Hydrogen Phosphate ◽  
Wet Process ◽  
New Type ◽  
Probe Spectroscopy ◽  
Existing Form

Abstract The phosphorus-sulfur two-step production process was developed in the wet-process phosphoric acid industry to solve phosphogypsum pollution. However, phosphate rock acid-insoluble residue is produced during this process as a new type of solid waste, which had a high potential for recycling. For process reasons, this type of residue still contains a certain amount of fluorine and phosphorus, which has a massive impact on the potential uses of phosphate rock acid-insoluble residue. Therefore, X-ray photoelectron spectroscopy, Raman, electron probe spectroscopy and scanning electron microscopy were used to examine the existing form and distribution of fluorine and phosphorus in phosphate rock acid-insoluble residue. The mass fraction of F and P2O5 were 9.407% and 11.862%, respectively. Fluorine existed mainly in the form of fluorite, fluorapatite and metal fluoride. Phosphorus existed mainly in the form of fluoroapatite, phosphate, hydrogen phosphate and dihydrogen phosphate. The total phosphate, hydrogen phosphate and dihydrogen phosphate contents were much higher than that of fluoroapatite, whereas the fluoroapatite content was higher than that of fluorite and metal fluoride. Fluorine and phosphorus were distributed in the form of agglomerates in the phosphate rock acid-insoluble residue. Fluorine and phosphorus were partially correlated, showing a weak relationship in the high phosphorus area.

Synthesis of sodium ammonium hydrophosphate and sodium dihydrophosphate based on extraction phosphoric acid from Central Kyzylkum phosphorites

2021 ◽  
pp. 19-25
Keyword(s):  
Phosphoric Acid ◽  
Sodium Carbonate ◽  
Gaseous Ammonia ◽  
Dihydrogen Phosphate ◽  
Hydrogen Phosphate ◽  
Sodium Dihydrogen Phosphate ◽  
Ammonium Hydrogen ◽  
Ammonium Hydrogen Phosphate ◽  
Sodium Dihydrogen ◽  
Extraction Phosphoric Acid

The aim of the research is the synthesis of sodium ammonium hydrogen phosphate and sodium dihydrogen phosphate based on purified extraction phosphoric acid. The acid was purified from accompanying impurities by precipitation methods using sodium carbonate and metasilicate, washed burnt phosphoconcentrate, barium carbonate, acid neutralization with gaseous ammonia. Pre-neutralization of the purified solution of monoammonium phosphate with sodium carbonate to the ratio Na2O:P2O5 = 0.44 and subsequent drying at a temperature of 50 °С allows to obtain sodium ammonium hydrogen phosphate tetrahydrate, and at 100 °С sodium dihydrogen phosphate monohydrate. The individuality and purity of the synthesized substances was established by the methods of X-ray diffraction, IR spectroscopy, thermogravimetry and scanning electron microscope.

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