Sodium Pyrophosphate Solution Research Articles

Novel biodegradable polymers modified by humic acids

The possibility of using humic acids (HA) as hybrid modifiers is considered. They were taken from lignite using first sodium pyrophosphate solution, then a 1 % solution of NaOH for extraction, and next mineral acid for precipitation. It has shown that in gelatin–HA hybrid systems, the latter mainly join water molecules and “sequester” them to prevent their interaction with gelatin chains. In the hydroxypropyl methylcellulose (HPMC)-HAs systems, the processes of polymer cross-linking through multipoint chelate interaction with the carboxylate group of HAs have been determined. Hybrid polyvinyl alcohol (PVA)-HAs structures are obtained by the matrix synthesis mechanism. Also, during the hybrid modification of PVA with HAs, additional supramolecular interactions, in addition to hydrogen bonds, occur between their functional groups as a result of crystallization. It was found that hybrid modification of HAs within the matrix synthesis of gelatin-based biopolymer hydrogels allows obtaining polymer hydrogels with an increased swelling degree and gives them antibacterial qualities. The optimal content of HAs in biodegradable polymers based on gelatin, PVA and HPMC is 10 % by mass.

Unraveling the persistence of deep podzolized carbon: Insights from organic matter characterization

Over a billion tons of terrestrial carbon (C) is stored in deep soils from the Southeastern Coastal Plain of the United States. While the size and extent of this pool, known as deep podzolized carbon (DPC), have been reported in recent studies, the stabilization mechanisms responsible for its persistence are unclear. The main hypothesis of DPC stabilization is that hydrology, specifically water table fluctuations in the phreatic zone, slow microbial degradation and promote C accumulation. This accounts for the characteristic properties and distribution of DPC and provides a mechanistic distinction between DPC and shallow podzolized C in the region's soils, however it has yet to be tested. We characterized the organic matter composition of the bulk and dissolved fractions of DPC using elemental analysis, solvent extraction, infrared spectroscopy, and high-resolution mass spectrometry. Consistent with past work, the majority of DPC organic matter was extractable by sodium pyrophosphate solution; the influence of metal association was also observable in the water extractable fraction of DPC with large species being preferentially removed and a low compound diversity compared to those from other horizons overlying DPC. Only water extractable species with low molecular mass (m/z < 375 Da) showed significant change in average nominal oxidation state of carbon (NOSC) values, indicative of oxygen-limitation influence on the processing of these species. Infrared spectroscopy revealed an increase in abundance of aliphatic (C-H:C-O) bonds relative to polysaccharide bonds with depth whereas aromatic (C=C:C-O) bonds decreased with depth in DPC relative to other subsurface horizons. Our work shows that DPC is significantly more refractory than overlying surface soil C, and yet slightly more labile than the subsoils above DPC. Together our results suggest that the maintenance of low redox conditions via persistent water saturation contributes to the stabilization and persistence of DPC.

Sequential extraction of labile and recalcitrant fractions of soil organic matter: A case study focusing on antimony (Sb) in humic acids, fulvic acids and humin fractions of long-term aged contaminated soils

Soil organic matter (SOM) plays a key role in environmental chemistry of macro and micro nutrients as well as heavy metal (loids). In this research, a modified sequential extraction scheme was used to isolate labile and recalcitrant SOM from organic rich soils after 18 months of ageing with antimony. Humic substances were extracted with a mixture of 0.5 M sodium hydroxide +0.1 M sodium pyrophosphate solution from soils. Then soils deprived of humic substances were sequentially subjected to extraction with glycerol, citric acid, pre-treated with acid and extracted with boiling alkali mixture. The humic acids (HA) and fulvic acids (FA) of isolated SOM fractions were separated and HAs been characterized using FTIR, 1H NMR, and UV-VIS. Acid-alkali treatment of the most recalcitrant SOM fraction (A1-ROM) led to the extraction of sparingly soluble, highly aromatic compound with considerable amounts of N (44% of the extractable N), possibly due to the breakdown of bounds between aromatic rings and amine functional groups. Nevertheless, the highest content of C and TOC was associated with the glycerol extractable SOM. Substantial amounts of Fe and Al were extracted with glycerol, resulting in a dramatic rise of Sb in SOM extracts. The largest increase (60%) in Sb concentrations was observed after the removal of Fe with citric acid. The humic substances (HS) were responsible for 63% of extractable Sb, whereas even after exhaustive alkali extractions 22% of the total Sb remained in the residual humin fraction. Within the HS fraction, 95% of antimony was associated with the low molecular weight FAs. Antimony concentrations in organic fractions correlated significantly with TOC and N contents, possibly due to the role of amine functional groups in Sb complexation. The results of this research highlight the importance of Fe–Al-SOM bridging and humin fraction in sequestration of Sb in recalcitrant SOM pools.

In vitro antibacterial effect of nanomaterial calamine

Calamine can be made into clinical medicinal powder by the traditional calcination water flying method, but its particle size distribution is wide and its specific surface area is small. The application of nanomaterials in traditional Chinese medicine materials shows that part of them can improve the efficacy of traditional Chinese medicine materials. Therefore, this paper attempts to explore the application of nanomaterials in calamine and analyzes the antibacterial effect of nanocalamine in vitro. The experimental results show that the particle size measured by 0.3% sodium pyrophosphate solution is basically consistent with that measured by electron microscope, and polymer dispersity index (PDI) is the smallest. Therefore, 0.3% sodium pyrophosphate solution was selected as the best dispersion medium of calamine nanoparticles. Nanocalamine has the properties of medicinal calamine and nanotraditional Chinese medicine. It shows the active effect of calamine and nanoparticle. The antibacterial activity of nanocalamine is stronger than that of medicinal calamine. The antibacterial activity of calcined calamine is stronger than that of medicinal calamine and weaker than nanocalamine. Alkaline zinc carbonate has no antibacterial activity. Nanocalamine has the characteristics of medicinal calamine and nanotraditional Chinese medicine, which shows the positive role of calamine and nanoparticles.

Inhibition of Mineralization of Urinary Calcium Phosphate Stones by Sodium Pyrophosphate

To understand the biological importance of sodium pyrophosphate and its applicability as inhibitors in urolithiasis disease, we have studied the inhibition efficiency of sodium pyrophosphate towards the mineralization of urinary stone forming minerals like calcium phosphate, in aqueous as well as urinary medium. An attempt has been made to unfold, tentatively, the mechanism of inhibition by this inhibitor. It was Observational experiment. The Study was Conducted in the chemistry lab of university department of chemistry, B N Mandal University, Madhepura (Bihar) An experimental model was designed by taking the salt forming solutions, the whole operation took about 40-50 min. At the end the contents of beaker were digested in a hot water bath, cooled to room temperature and centrifuged in small volumes. The total centrifugate was collected and Calcium and carbonate content of the centrifugate of calcium carbonate mineralization experiments were determined. Sodium pyrophosphate has a moderate inhibition efficiency towards calcium carbonate mineralization. At 0.05 M concentration, sodium pyrophosphate has a net inhibition of 30 % which is 26.65 % more than that of water (blank). Compared to water the percentage inhibition increased by 795.52%. With decreasing concentrations of sodium pyrophosphate, the inhibition efficiency decreases. At very low concentration (0.01 M) its inhibition is only slightly higher than that of water. In urinary medium sodium pyrophosphate seems to function as a better inhibitor of phosphate mineralization. At 0.05 M concentration, sodium pyrophosphate has a net inhibition of 89.22 % which is 75.36 % more than that of urine. It is observed that sodium pyrophosphate solution, under different concentrations, exhibits moderate to good efficiency of inhibition towards mineralization of urinary stone forming minerals like calcium carbonate in aqueous as well as urinary medium.

Quantitative detection of gold nanoparticles in soil and sediment

Ever-growing application of engineering nanoparticles in many sectors of the society requires efficient methods to extract them from soil and sediment, for the sake of environmental protection. In this study, we develop a new method which uses sodium pyrophosphate solution (TSPP, Na4P2O7) as extratant to extract gold nanoparticle (AuNPs) from soil and sediment under optimized parameters through vortexing, water bath oscillation, ultrasonic bath and precipitation. SP-ICP-MS was used for the detection of number concentration, mass concentration and size distribution of AuNPs in soil. UV irradiation was innovatively used to directly degrade soil organic matter to improve the recovery of AuNPs due to their low recovery rate in rich organic soils. It could be found that the mass fraction recovery increased from 36% (without UV digestion) to 83% (with 48h UV digestion). The extraction method is versatile for different coating layers and wide-ranging particle sizes in real soil and sediment. Therefore, the rapid and efficient characterization and quantification of AuNPs in soil and sediment are achieved, and the researches on the extraction method of AuNPs and their behavior and toxicity assessment in soil environment can be enriched.

Effect of sodium pyrophosphate and understanding microstructure of aqueous LAPONITE® dispersion using dissolution study

In this work, we investigate the physical origin of ergodicity breaking in an aqueous colloidal dispersion of synthetic hectorite clay, LAPONITE®, by performing dissolution and rheological experiments with monovalent salt and tetrasodium pyrophosphate solution. We also study the effect of pH and nature of interface, nitrogen and paraffin oil on the same. Dissolution experiments carried out for dispersions with both the interfaces show similar results. However, for samples with a nitrogen interface, all the effects are observed to get expedited in time compared to a paraffin oil interface. When kept in contact with water, 1.5 wt.% and 2.8 wt.% colloidal dispersion at pH 10 swells at small ages, while it does not swell at large ages. The solution of tetrasodium pyrophosphate, interestingly, dissolves the entire colloidal dispersion sample with pH 10 irrespective of the concentration of clay. Experiments carried out on colloidal dispersions prepared in water having pH 13 demonstrate no effect of water as well as sodium pyrophosphate solution on the same suggesting a possibility of the presence of negative charge on edge at that pH. We believe that all the behaviors observed for samples at pH 10 can be explained by an attractive gel microstructure formed by edge-to-face contact. Furthermore, the absence of swelling in old colloidal dispersion at pH 10 and dissolution of the same by sodium pyrophosphate solution cannot be explained by merely repulsive interactions. This behavior suggests that attractive interactions originating from edge-to-face contact play an important role in causing ergodicity breaking in the colloidal dispersions at pH 10 at all the ages irrespective of the clay concentration. We further substantiate the presence of a fractal network structure formed by interparticle edge–face association using rheological tools and cryo-TEM imaging. We also conduct a comprehensive study of the effect of tetrasodium pyrophosphate on the sol–gel transition of LAPONITE® dispersion.

Regularities of extracting humic acids from soils using sodium pyrophosphate solutions

Regularities of extracting humic acids from different soil types (soddy-podzolic soil, gray forest soil, and all chernozem subtypes) with sodium pyrophosphate solutions at different pH values (from 5 to 13) have been studied. It is found that, regardless of soil type, the process occurs in two stages through the dissociation of carboxylic groups and phenolic hydroxyls, each of which can be described by a logistic function. Parameters of the logistic equations approximating the extraction of humic acids from soils at different pH values are independent of the content and composition of humus in soils. Changes in the optical density of humic acids extracted from soils using sodium pyrophosphate solutions with different pH values are described in the first approximation by the Gaussian function. The optically densest humic acids are extracted using sodium pyrophosphate solutions at pH 10. Therefore, it is proposed to use an extract with pH 10 for the characterization of organic matter with the maximum possible degree of humification in the given soil.

Calcium pyrophosphate powder for production of bioceramics synthesized from pyrophosphoric acid and calcium acetate

Hydrated amorphous calcium pyrophosphate powder was synthesized from an aqueous solution containing pyrophosphoric acid and calcium acetate with the addition of an aqueous solution of ammonia. A distinctive feature of the proposed synthesis consisted in the use of pyrophosphoric acid synthesized by treatment of a sodium pyrophosphate solution with ion exchange resin (H+ form). The phase composition of ceramic fabricated from the powder after the calcination at 600–1000°C was represented by β-Ca2P2O7. The synthesized powder can be recommended for the fabrication of porous biocompatible resorbable ceramic.

Distribution of transformed organic matter in structural units of loamy sandy soddy-podzolic soil

The effect of land use types and fertilizing systems on the structural and aggregate composition of loamy sandy soddy-podzolic soil and the quantitative parameters of soil organic matter has been studied. The contribution of soil aggregates 2–1 mm in size to the total Corg reserve in the humus horizon is higher than the contributions of other aggregates by 1.3–4.2 times. Reliable correlations have been revealed between the contents of total (Corg), labile (Clab), and active (C0) organic matter in the soil. The proportion of C0 is 44–70% of Clab extractable by neutral sodium pyrophosphate solution. The contributions of each of the 2–1, 0.5–0.25, and <0.25 mm fractions to the total C0 reserve are 14–21%; the contributions of each of the other fractions are 4–12%. The chemically labile and biologically active components of humic substances reflect the quality changes of soil organic matter under agrogenic impacts. A conceptual scheme has been proposed for the subdivision of soil organic matter into the active, slow (intermediate), and passive pools. In the humus horizon of loamy sandy soddy-podzolic soil, the active, slow, and passive pools contain 6–11, 34–65, and 26–94% of the total Corg, respectively.

Assessing Stability of Humus in Soils from Continuous Rice-Wheat and Maize-Wheat Cropping Systems using Kinetics of Humus Desorption

To assess soil quality with respect to carbon sequestration, one should know not only the amount of carbon present in soil but also the strength with which the carbon is held to the mineral surfaces. A chemical method based on batch desorption of adsorbed humus on clay humus complex by sodium hydroxide–sodium pyrophosphate solution was used to assess the stability of humus carbon using soils from two systems of continuous cropping such as rice-wheat and maize-wheat. Humus desorption data were found to be very closely fitted to a linear combination of three first-order equations indicating three different pools of carbon. Humus retention was found to be related to poorly crystalline smectites. Rice-wheat system showed greater contrasting difference in humus stability than maize-wheat system along the depth of the soil profile.

Ferromagnetic Coupling in "Double-Bridged" Dihydrogenpyrophosphate Complexes of Cobalt(II) and Nickel(II).

Three isostructural compounds of the formula {[M(bipy)(H2O)(H2P2O7)]2·2H2O} [bipy = 2,2'-bipyridine; M = Ni (1), Co (2), Mn (3)] have been isolated from aqueous solutions containing the corresponding metal(II) chloride hydrate with a bipy and sodium pyrophosphate solution in a 1:1:2 molar ratio, and their structures were determined by single-crystal X-ray diffraction. The structures of 1-3 consist of neutral aqua(2,2'-bipyridine)metal(II) dinuclear units bridged by two dihydrogenpyrophosphate groups adopting a bidentate/monodentate mode. Each metal ion in 1-3 is six-coordinate in a distorted octahedral geometry, with the reduced value of the angle subtended by the chelating bipy at the metal ion [79.6(1)° (1), 77.32(7)° (2), and 72.9(1)° (3)] being the main source of this distortion. The values of the intramolecular metal-metal separation are 5.271(1) Å (1), 5.3065(8) Å (2), and 5.371(1) Å (3). Magnetic susceptibility measurements on polycrystalline samples of 1-3 in the temperature range 1.9-300 K shows weak intramolecular ferromagnetic [J = +1.86(2) cm(-1) (1) and +0.25(1) cm(-1) (2)] and antiferromagnetic [J = -0.48(1) cm(-1) (3)] coupling, with the spin Hamiltonian being defined as H = -JSM1·SM1a. This rarely observed coordination mode for dihydrogenpyrophosphate leads to ferromagnetic coupling in complexes of nickel(II) or cobalt(II).

Lepkość roztworów pirofosforanu sodu i heksametafosforanu sodu w wodzie destylowanej

Lepkość roztworów pirofosforanu sodu i heksametafosforanu sodu w wodzie destylowanej

Gęstość roztworów pirofosforanu sodu i heksametafosforanu sodu w wodzie

Gęstość roztworów pirofosforanu sodu i heksametafosforanu sodu w wodzie

Composto orgânico com altos teores de níquel e sua biodisponibilidade no sistema solo planta

A utilização de biossólidos industriais na agricultura pode proporcionar aumento de níquel no solo, porém sua biodisponibilidade é influenciada por diversos fatores e, muitas vezes, resíduos com elevados teores de níquel não estão associados à sua alta absorção pela planta. O objetivo foi avaliar a solubilidade do níquel no solo, sua biodisponibilidade e acumulação em plantas. O experimento foi conduzido em vasos em delineamento inteiramente casualizado com seis doses de níquel: 0, 9, 18, 36, 72 e 144 mg de níquel kg-1 de solo, via fonte orgânica (biossólido compostado) e mineral (cloreto de níquel) com 4 repetições. Utilizou-se um Cambissolo Háplico como substrato e o morangueiro como planta indicadora. Avaliaram-se os teores no solo pelos extratores: ácido nítrico + clorídrico concentrado (3:1), nitrato de cálcio a 0,5 mol L-1, ácido nítrico a 1,0 mol L-1 e o pirofosfato de sódio a 0,1 mol L-1 além, ainda, dos teores de níquel na raiz, coroa, parte aérea e fruto. As maiores e menores extrações de níquel no solo foram observadas pela aplicação da fonte orgânica e extração com o ácido nítrico e clorídrico concentrado e pelo nitrato de cálcio, respectivamente. Ambas as fontes aumentaram os teores de níquel nos tecidos avaliados, com menores aumentos para fonte orgânica. Os maiores teores foram observados em raiz e os menores em coroa.

Preparation of titanium phosphates with additives in hydrothermal process and their powder properties for cosmetics

In this study, titanium phosphates were prepared from titanium chloride and phosphoric acid, sodium pyrophosphate and sodium triphosphate solutions with water retention compounds in hydrothermal process as a novel white pigment for cosmetics. Their chemical composition, powder properties, photo catalytic activity, water retention and smoothness were studied. The addition of glycerin in the preparation from sodium pyrophosphate has the useful method to obtain homogenized spherical particles of titanium phosphate pigments for the cosmetics. These titanium phosphates had less photo catalytic activity to protect the sebum on the skin.

Special features of humus acids extraction from soils by sodium pyrophosphate solutions of different alkalinity

The regularities of extracting humus acids from soils of different types with solutions of sodium pyrophosphate at the equilibrium pH values of 5–13 were studied. The increase in the humus acids yield from the soils with the increasing alkalinity of the solution applied is directly related to the capability of acid functional groups (carboxyl and phenol hydroxyl) for dissociation at definite pH values. The regularities of the changes in the chemical nature and degree of humification of humus acids extracted from the soils related to the pH of the solution were revealed. A sodium pyrophosphate solution (pH 10) was suggested for extracting the humus acids most active in the given soil.

Elemental and Fourier Transform-Infrared Spectroscopic Analysis of Water- and Pyrophosphate-Extracted Soil Organic Matter

Abstract Soil organic matter (SOM) plays an important role in soil fertility and, thus, in sustaining potato production. To investigate the impact of crop rotation on SOM composition, we sequentially extracted SOM by water (WEOM) and sodium pyrophosphate solution (PEOM) from different 3-year potato crop rotations with or without irrigation and quantified its elemental compositions. Different contents of P, Ca, Al, and Fe were observed among the PEOM fractions from fields with different crop rotations. Elemental contents in PEOM from irrigated treatments were consistently lower than those from the corresponding rainfed treatments. The structural features of these WEOM and PEOM samples were further characterized by Fourier transform-infrared (FT-IR) spectroscopy. Generally, the impacts of rotation and irrigation practices reflected on the changes of FT-IR band intensities in 3,020-2,800 cm−1 (aliphatic groups) and 1,640-1,600 cm−1 (aromatic compounds) of WEOM samples. The FT-IR spectroscopic analysis indicated that PEOM was more enriched in aliphatic, carboxyl, and aromatic compounds than WEOM. However, neither crop rotation nor irrigation changed the relative abundance of these functional groups in PEOM. This research improves our understanding of how the properties of SOM may be impacted by crop management.

A novel method of synthesizing solid phase adsorbent silica modified with xylenol orange: application for separation, pre-concentration and determination of uranium in calcium rich hydro-geochemical samples and sea water—Part 1

A novel, single-step route has been developed for the synthesis of solid phase adsorbent silica modified with xylenol orange. The addition of cationic surfactant cetyl tri-methylammonium bromide during the synthesis of the adsorbent supports the formation of a stable coating of xylenol orange on silica. The adsorbent showed no signs of degradation in contact with organic solvents and with solutions of varying pH between 1 and 9. This adsorbent has been used for separation and pre-concentration of uranium from hydro-geochemical samples with high calcium content and from sea water. Quantitative sorption of uranium was observed above pH 3 and complete desorption can be achieved using 0.2 M sodium pyrophosphate solution. The uranium content in the extract was determined by laser fluorimetric technique. The equilibration time is 30 min. The sorption capacity of the adsorbent for uranium is 10 mg g−1. An enrichment factor of 50 was obtained by this procedure taking 500 mL of sample solution. Uranium concentrations down to 0.05 ng mL−1 can be determined after pre-concentration using this method. The relative standard deviation at an 0.1 ng mL−1 level is ±15%.

Buoyancy weighing-bar method: A particle size distribution measurement using a new settling method

The buoyancy weighing-bar method is a new settling method of a particle size distribution measurement. Using this method, we measured the particle size distributions of the test powders standardized by Japanese Industrial Standards. The particle size distributions of the JIS Test Powders 1, class 4 (Talc), class 5 (Fly ash), class 8 (KANTO (Japanese) loam) measured using sodium pyrophosphate solution or ethanol as a dispersed liquid. The particle sizes of the JIS Test Powders 1, class 4 (Talc) and class 8 (KANTO (Japanese) loam) could be measured from 5 to 75μm in 2 h of measuring time. The particle size distribution of JIS Test Powders 1, class 4 (KANTO (Japanese) loam) measured by this method was close to those measured by the other settling methods and the laser diffraction/scattering method. However, the particle size distributions of the JIS Test Powders 1, class 4 (Talc) and the JIS Test Powders 2, No. 4 (White fused alumina) measured by this method were different from those measured by the laser diffraction/scattering method. There is no effect of the particle concentration on the particle size distribution when the particle concentrations of the JIS Test Powders 2, No. 4 (White fused alumina) are 10kg/m3 or less.