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Introduction
Published in Arthur W. Hounslow, Water Quality Data, 2018
A major concern with water quality is human health and disease. Cancer may result from excessive Cd, Ni, and Pb. The study of potential carcinogens involves massive data collection and interpretation. Cardiovascular disease is also of great interest, and this involves the study of Ca, Mg, and water softening. Urolithiasis, that is, the occurrence of kidney stones, because of the build-up of Ca oxalate and Ca phosphate is also of continuing interest. The hydrosphere contains the drinking water of the world. Therefore, the primary interest is to keep drinking water supplies free of toxic contaminants, whether they be heavy metals or trace amounts of toxic organic contaminants. In addition to the detection and attenuation of these compounds, the major concern is in the determination of their mobility.
Solid-Phase Heavy-Metal Separation with Selective Ion Exchangers
Published in Arup K. Sengupta, Ion Exchange and Solvent Extraction, 2017
Sukalyan Sengupta, Tabish Nawaz
Another experiment was conducted in a higher suspended solids content reactor. The solid phase in this experiment was prepared by mixing 5 g of CaCO3(s), 45 g of fine sand (−200 mesh), 13.4g of Na2C2O4, and 0.38g of CuO(s). One liter of DI water was added to this mixture, and the pH was adjusted to 9.0. The aqueous-phase oxalate concentration was 4000 mg/L, and <1% CuO(s) was present in the solid phase of the sludge. Sorption/desorption steps were subsequently carried out for 10 cycles, with Cu(II), Ca(II), and oxalate being analyzed after each cycle. Oxalate was analyzed using an ion chromatography with conductivity detector and standard carbonate/bicarbonate eluent.
Monodispersed fine particles of calcium oxalate: morphological dynamics with tuning of the experimental parameters
Published in Journal of Dispersion Science and Technology, 2023
Khalida Akhtar, Shahana Abad, Hina Khalid, Naila Zubair, Syed Sajjad Ali Shah
In particular, calcium oxalate, a calcium salt of oxalate (CaC2O4·xH2O, where x varies from 0 to 3) is the most common biominerals in nature and the most complete group of living materials found in hydrothermal veins. It can crystallize into three forms, that is, monohydrate, dihydrate, and trihydrate, while the monohydrate occurs naturally in the form of minerals in plants forming envelope-shaped crystals and it is thermodynamically stable. Calcium oxalate is one of the major inorganic components of renal stones.[9] Thus, in renal stones, only monohydrate and dihydrate forms were found. These three different forms of calcium oxalate show properties that end up being the focus of various fields of material sciences namely cultural heritage and biomedicine.[10] It is used as a precursor for calcium carbonate and calcium oxide, as it thermally decomposes at different temperatures into these compounds.[11] Furthermore, calcium oxide finds its application in the manufacturing of paper, cement, and high-grade steel and is widely used for medical purposes. While calcium carbonate is used in environmentally friendly items such as drug delivery, microcapsules, and bone-filling materials.[12]
Optimization of oxalate-free starch production from Taro flour by oxalate oxidase assisted process
Published in Preparative Biochemistry & Biotechnology, 2021
Moni Philip Jacob Kizhakedathil, Suraksha Suvarna, Prasanna D. Belur, Rungtiwa Wongsagonsup, Esperanza Maribel G. Agoo, Jose Isagani B. Janairo
The response surface plots considering two factors at a time, while maintaining the other factor at a fixed level, are helpful in understanding the adequacy of the range selected. The response surface curves for the oxalate removal from the produced starch are shown in Fig. 2. In all the figures, curves are convex in nature indicating that the range selected for all the variables are adequate and the true optimum lies in the design space. The shapes of the contour plots indicate the nature and extent of the interactions. Enzyme load and taro flour concentration are found to exhibit prominent interactions and hence having an elliptical contour plot, whereas the less prominent or negligible interactions produced circular contour plots (Fig. 2). The positive signs of squared coefficients indicated that the parabola would be open upwards (suggesting a maximum point). Response optmizer was used to determine the optimal treatment conditions for taro flour. Based on the predictions by software, it was predicted that 4% taro flour (w/v) (4 g of taro flour suspened in 100 ml buffer) with an enzyme load of about 100 U/mg incubated for period of 150 min can effectively reduce the oxalate content. Validation experiments were carried out based on the predictions by the optimizer. After the extraction of starch, HPLC analysis was performed in duplicates in order to estimate the oxalate content. HPLC analysis of the starch thus produced, indicated that the oxalate content was about 38 mg/100 g starch, which is about 98.37% reduction in the total oxalate content when compared with taro flour. This oxalate content is 54% less than the maximum permissible oxalate content in the food, which is about 71 mg/100 g (on dry weight basis).[10]
Comparison of the adhesion and endocytosis of calcium oxalate dihydrate to HK-2 cells before and after repair by Astragalus polysaccharide
Published in Science and Technology of Advanced Materials, 2019
Jin Han, Da Guo, Xin-Yuan Sun, Jian-Min Wang, Jian-Ming Ouyang, Bao-Song Gui
The inhibitory effect of APS on COD adhesion was confirmed by SEM (Figure 7). The amount of adhered crystals on the cell surface of the injury group was greater than that of the control group. The amount of crystal adhesion of each polysaccharide repair group was between that of the injury and control groups. APS1, which had the strongest ability to repair damaged cells, had the strongest ability to inhibit nano-COD adhesion. APSs inhibited the adhesion of calcium oxalate crystals and may hinder the formation of kidney stones.