ca ions
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2021 ◽  
Vol 926 (1) ◽  
pp. 012082
Author(s):  
N Wahyuni

Abstract A high concentration of calcium ions in water is a problem as it can cause blockages in engine pipes. Adsorption is a relatively cheap and straightforward method that can be used to reduce the calcium ion content in water. Kaolin is a mineral that has a potential as an adsorbent and whose adsorption capacity can be increased by activation. This research studied the adsorption capacity of activated kaolin by hydrochloric acid against Ca2+ ions. Kaolin was chemically activated using 6 M HCl solution for 24 hours. The adsorption contact time in batches was varied with time variations of 30, 90, 150, and 180 minutes. The maximum adsorption capacity of activated kaolin to the Ca2+ was determined by varying the initial concentrations of water samples, namely 4, 7, 10, and 13 mg/L. The concentration of Ca2+ was determined by a titration method using ethylene diamine tetraacetate (EDTA). The results showed that the activation of kaolin with 6 M HCl at the optimum contact time of adsorption, namely 150 minutes, increased the percentage of adsorbed Ca ions to 2 times of that of natural kaolin, from 33.3% to 68.3%. Based on the Langmuir equation, the maximum adsorption capacity of calcium ions by activated kaolin HCl 6 M increased 1.7 times from natural kaolin to 0.346 mg/g.


2021 ◽  
Author(s):  
Stefan Rusu ◽  

In the paper is described the mono- and poly-invasions impact on some morpho-functional indices in wild boars. So, in result of the investigation of hematological indices in uninfested mono- and poly-parasitized wild boars, it was established that both the indices of hemoglobin content, of hematocrit, erythrocyte’s number, thrombosis time and ESR (erythrocyte sedimentation rate) vary and are more increased in the I group with uninfested wild boars compared to mono - and poly-parasitized ones. It has been established that at infested boars with S. papillosus from the I group, and in those infested with D. lanceolatum from the II group there is a decrease of hemostatic indices, but their maximum decrease is highlighted in the IV group with wild boars infested with Dicrocoelium lanceolatum, Strongyloides papillosus, Metastrongylus elongatus and Eimeria debliecki. This decrease is due to eliminated exotoxins by parasites, which contain anticoagulants and hemolyzers and which neutralize the fibrinogen, thrombin, Ca+ ions and vitamin K properties from the body.


Vestnik ◽  
2021 ◽  
pp. 208-214
Author(s):  
Б.К. Кайрат ◽  
С.Т. Тулеуханов ◽  
В.П. Зинченко

Ионы Са являются основным мессенджером в регуляции физиологических функций клеток. Внутриклеточном пространстве ионы Ca могут свободно состоянии диффундироваться в различных частях цитоплазмы, в то же время значительное количество Ca в связанном виде накапливается в различных внутриклеточных депо или в составе кальций-связывающих белков. Регуляция физиологических процессов с ионами внутриклеточного Са происходит в диапазоне концентраций 10 М, тогда как концентрация Са во внеклеточном пространстве выше и составляет 10 М, для поддержании градиента концентраций в клетках имеются важные Са транспортирующие системы плазматической мембраны, эндоплазматического ретикулума и митохондрий. В нейронах функционируют внутриклеточные ферменты и белки плазматической мембраны для поддержания Са-гомеостаза и реализации механизмов внутриклеточной сигнализации для обеспечения жизнедеятельности в выживании клеток. Нарушение или гиперактивация одного или нескольких механизмов кальциевой сигнализации может привести к повреждению и гибели нейронов в случае отсутствия компенсаторных механизмов. Ca ions are a key messenger for the regulation of most of the physiological functions of cells. Inside the cell, Ca ions can freely diffuse in various parts of the cytoplasm, but a significant amount of Ca is also bound in various intracellular depots or in the form of calcium-binding proteins. The regulation of physiological processes by intracellular Ca ions occurs in the concentration range of 10 M, and the concentration of Ca in the extracellular space is higher and is 10 M, and to maintain this concentration gradient, cells have Ca-transporting systems of the plasma membrane, endoplasmic reticulum and mitochondria. In neurons, a large number of intracellular enzymes and plasma membrane proteins function to maintain Ca-homeostasis and implement intracellular signaling mechanisms to ensure vital activity in the survival of cells. Violation or hyperactivation of one or more mechanisms of calcium signaling can lead to cell damage and death in the absence of compensatory mechanisms.


2021 ◽  
Author(s):  
Katarzyna Jadwiga Stanienda-Pilecki

Abstract The results of researches of the selected trace elements: Ti, Sr, Ba, Zn, and also Cr, Ni, Cu, Zr, Mo, Pb, Rb, Mn, Na, K, P, Y and REE (REY) content were presented in this article. The elements were measured in the carbonate minerals of Muschelkalk (Middle Triassic) limestones of the Opole Silesia in Poland, using two methods: ICP MS spectrometry and X-ray fluorescence. These methods are characterized by very high precision and sensitivity of measurements. The results of researches show that the content of analyzed trace elements varies in from value below 1 ppm up to some hundreds ppm. However, the highest contents were measured for strontium and barium, elements characteristic for aragonite carbonate phase which is transformed such as high-Mg calcite into low magnesium calcite during diagenesis. So as Sr and Ba indicate the presence of aragonite in the primary carbonate material. The other trace elements probably form substitutions in clay or carbonate minerals. Some of trace elements such as Zn, Pb, Cu, Mo, Ni may also be associated with sulfide minerals and Ti, Cr, Mn, with oxides. Some measured REY elements- Ce, Nd, Sm, Gd, Dy, Er and Y are found in the rocks in very small quantities. So their content is really very low. It varies in from value below 1 ppm up to 6 ppm. REY usually substitute Ca ions in calcite.


Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3642
Author(s):  
Massimiliano Bartolomei ◽  
Paul Martini ◽  
Ricardo Pérez de Tudela ◽  
Tomás González-Lezana ◽  
Marta I. Hernández ◽  
...  

We present a combined experimental and theoretical investigation on Ca+ ions in helium droplets, HeNCa+. The clusters have been formed in the laboratory by means of electron-impact ionization of Ca-doped helium nanodroplets. Energies and structures of such complexes have been computed using various approaches such as path integral Monte Carlo, diffusion Monte Carlo and basin-hopping methods. The potential energy functions employed in these calculations consist of analytical expressions following an improved Lennard-Jones formula whose parameters are fine-tuned by exploiting ab initio estimations. Ion yields of HeNCa+ -obtained via high-resolution mass spectrometry- generally decrease with N with a more pronounced drop between N=17 and N=25, the computed quantum HeNCa+ evaporation energies resembling this behavior. The analysis of the energies and structures reveals that covering Ca+ with 17 He atoms leads to a cluster with one of the smallest energies per atom. As new atoms are added, they continue to fill the first shell at the expense of reducing its stability, until N=25, which corresponds to the maximum number of atoms in that shell. Behavior of the evaporation energies and radial densities suggests liquid-like cluster structures.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Fatemeh Bitarafan ◽  
Mehrnoosh Khodaeian ◽  
Elham Amjadi Sardehaei ◽  
Fatemeh Zahra Darvishi ◽  
Navid Almadani ◽  
...  

Abstract Background Ca2+ as a universal second messenger regulates basic biological functions including cell cycle, cell proliferation, cell differentiation, and cell death. Lack of the protein mitochondrial calcium uptake1 (MICU1), which has been regarded as a gatekeeper of Ca ions, leads to the abnormal mitochondrial Ca2+ handling, excessive production of reactive oxygen species (ROS), and increased cell death. Mutations in MICU1 gene causes a very rare neuromuscular disease, myopathy with extrapyramidal signs (MPXPS), due to primary alterations in mitochondrial calcium signaling which demonstrates the key role of mitochondrial Ca2+ uptake. To date, 13 variants have been reported in MICU1 gene in 44 patients presented with the vast spectrum of symptoms. Case presentation Here, we report a 44-year-old Iranian patient presented with learning disability, muscle weakness, easy fatigability, reduced tendon reflexes, ataxia, gait disturbance, elevated hepatic transaminases, elevated serum creatine kinase (CK), and elevated lactate dehydrogenase (LDH). We identified a novel nonsense variant c.385C>T; p.(R129*) in MICU1 gene by whole exome sequencing (WES) and segregation analysis. Conclusions Our finding along with previous studies provides more evidence on the clinical presentation of the disease caused by pathogenic mutations in MICU1. Finding more variants and expanding the spectrum of the disease increases the diagnostic rate of molecular testing in screening of this kind of diseases and in turn improves the quality of counseling for at risk couples and helps them to minimize the risks of having affected children.


Author(s):  
T. Makarova

Unsatisfactory physical condition of the soil in the village Oleksandrivka (Dniprovskyi district, Dnipropetrovsk region, Ukraine) necessitated a long-term research to find out the cause of this phenomenon. The type of soil of the experimental plot is established – chernozem ordinary low-humus leached on loamy forest. There are the soil section, the results of the spectral analysis of the soil, the humus content and the physicochemical properties of the soil of the research area. The article has the highlights results of chemical analysis of irrigation water from the reservoir on the Samara River. According to the results of the analysis, irrigated water belonged to the II quality class – "Limitedly suitable" in the all years of research. To establish the effect of class II water irrigation, the chemical composition of the water extract was determined. These researches showed on the anionic composition of the increase in SO4 ions relative to the option without irrigation for all years of observation. It was due to the entry of these ions into the soil along with irrigation water. Without irrigation the amount of sulfates gradually decreased. It was 2.25 meq/100 g of soil in the fifth year. There was a clear tendency to increase chlorine ions in irrigation option. The amount of chlorine increased to 1.5 times compared to the non-irrigated option. Therefore, the chemistry of the site was chloride-sulfate and sulfate. According to the cationic composition, the largest amount was accounted for by sodium ions. The amount of Na + 1 in the irrigated option increased by 34% on average when comparing with the control option. In the absence of irrigation, the site is slowly desalinated by reducing the ratio of Na/Ca ions by an average of 8.7 units compared to irrigated options. For some years of research the soil without irrigation option was referred to the slightly saline type.


2021 ◽  
Vol 58 (1) ◽  
pp. 19-26
Author(s):  
Ecaterina Matei ◽  
Andra Mihaela Predescu ◽  
Maria Rapa ◽  
Andreea Turcanu ◽  
Cristian Predescu ◽  
...  

The present paper reported the obtaining of an environmental friendly adsorbent based on sodium alginate, chitosan and glass bubbles. CaCl2 was used as crosslinking agent for sodium alginate favoring the interactions by physical bonds between the negative groups (-COO) of biopolymer and the Ca ions. The experimental study to determine the Cu(II) uptake using an atomic absorption spectrometer was conducted in the testing stand at the 1:50 and 1:100 ratios between the adsorbent mass and the amount of pollutant in solution. The number of cycles of regeneration of the adsorbent material was also evaluated. The characterization of alginate/chitosan/glass bubbles adsorbent by scanning electron microscopy (SEM) coupled with energy dispersive spectrometer (EDS) and Fourier transform infrared spectroscopy (FTIR) showed that the Cu(II) was found out on the surface of adsorbent.


2021 ◽  
Vol 587 ◽  
pp. 229-239
Author(s):  
Bassam I. El-Eswed ◽  
Mahmoud Sunjuk ◽  
Raed Ghuneim ◽  
Yahya.S. Al-Degs ◽  
Maha Al Rimawi ◽  
...  

2021 ◽  
Vol 69 (1) ◽  
pp. 37-42
Author(s):  
Md Mazharul Islam ◽  
Md Hossan Sohid Shoraoardy Bhuiyan ◽  
Rakibul Islam ◽  
Mohammad Shoeb ◽  
Md Iqbal Rouf Mamun ◽  
...  

This study was aimed to measure sediment and water quality parameter such as moisture and ash content, pH, TOC, TSS, BOD, TOC, DO, Electrical Conductivity (EC) and Na, K, Ca and Cr metal ions from Dhaleshwari River close to the Savar Tannery Estate (STE). The moisture and ash content of sediments were 23.45-31.42% and 2.09-5.80%, respectively. The pHs of sediment and water samples were 5.20-6.21 and 7.68-8.03, respectively. The average of Ca-hardness, DO and BOD in water were 885.9±88.8, 1.80±0.10 and 16.70± 1.43 mg/L, respectively. The EC of the sediment and water were 24.60-374.00 μS/cm and 32.80-39.50 mS/cm, respectively. The amount of TOC in sediment and water samples were 1.29-3.25g/100g and 2.28-2.70 mg/kg which are very low indicating the fewer amounts of plant and animal residues and sediment biota. TSS in water was 776-936 mg/L which is higher than the permissible limit (600 mg/kg). The Cr content was determined by AAS which implies that the sediment has significantly higher Cr content (38.78-681.62 mg/kg) compared to water (< 0.005 mg/L). The amount of Na and Ca ions were 26.81-45.00 and 16.04-27.36 mg/L, respectively while K ion was very negligible in water. Dhaka Univ. J. Sci. 69(1): 37-42, 2021 (January)


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