insoluble compounds
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2022 ◽  
Vol 2155 (1) ◽  
pp. 012025
Author(s):  
M K Kylyshkanov ◽  
N N Yaroshenko ◽  
I A Khlebnikova

Abstract The task of the research was to study and determine an effective method for the preparation of non-radioactive scandium compounds from uranium In-Situ Recovery (ISR) solutions. The widespread use of scandium is restrained by the high price due to its small production volumes, low content in the raw materials (scandium is a scattered element and does not form its own deposits), as well as the complexity of technological schemes for its extraction. Scandium receiving out of uranium reverses ISR solutions technological scheme was experimental tested, including sorption on MTS 9580 (Purolite’s production) ion exchanger with recurrent ballast impurities desorption and receiving concentrate that contains scandium. New radiation cleaning technological sequencing based on different solubility of radioactive elements and scandium in carbonate solutions, that accompanied by insoluble macro components complex formation, that contains in deactivated scandium concentrate and allows to get scandium oxide with desired component maintenance more than 94 % and less than 0,3 kilobecquerels/kg specific activity level was developed. The developed technology is based on the ability to form soluble carbonate complexes of scandium and radioactive elements, while the main macro components of the concentrate - ferrum, aluminum, calcium, silicon and others under the conditions of carbonation of the concentrate are inert or form insoluble compounds. Optimal radioactive impurity removing from concentrate conditions and scandium leaching from deactivated residue of scandium and macro impurity were studied and identified in laboratory conditions and during pilot tests.


Author(s):  
T. Raja Sekharan ◽  
R. Margret Chandira ◽  
S.C. Rajesh ◽  
Shunmugaperumal Tamilvanan ◽  
C.T. Vijayakumar ◽  
...  

Turmeric is a commonly known natural spice that contains many phytoconstituents. Among which Curcumin is a polyphenol present in turmeric responsible for many pharmacological actions. Curcumin is still used as a traditional medicine in fields such as Ayurvedic, Siddha, and Unani. Though Curcumin has a large number of activities, it has disadvantages, such as small shelf life due to poor chemical stability, poor absorption results in less bioavailability, less water solubility, rapid metabolism results in quick elimination from the systemic circulation. A Deep eutectic solvent (DES) is a new class of solvents. Hydrophobic DES can be used for dissolving water-insoluble compounds. DES can be prepared when two solid components mixed in a particular proportion are converted into liquid. DES can be used as a solvent for dissolving water-insoluble compounds and to increase the stability. In this work initially, curcumin linearity studies were conducted in different buffers. A buffer showing maximum absorbance was selected from the linearity studies. Then, DES was prepared by combining Camphor:Menthol (1:1) (CM-DES), Camphor:Thymol (1:1) (CT-DES) and, Menthol:Thymol (1:1) (MT-DES). The stability of curcumin in different DES was determined from the stock and working solutions in benchtop condition (room temperature) and, refrigerator condition (5±3°C). Only working solution stability was determined in the in vitro media temperature (37±2°C). From this study, it was concluded that 50 mM Sodium dihydrogen orthophosphate with 0.5% SLS at pH 5.5 showed maximum absorbance value compared with other buffers, so it was selected for further studies. From stability studies, it was found that curcumin in CM-DES was found to be stable in both stock and working solutions compared to the other two CT-DES and MT-DES.


Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7899
Author(s):  
Aleksandr Bakhtin ◽  
Nikolay Lyubomirskiy ◽  
Stanisław Fic ◽  
Tamara Bakhtina

Alternative binders activated by forced carbonisation are regarded as one of the potential solutions to reducing greenhouse gas emissions, water, and energy consumption. Such binders, in particular those based on nepheline sludge (a by-product of alumina production), cured in carbon dioxide with subsequent hydration, are clinkerless building materials. The development of such binders contributes to the involvement of multi-tonnage solid industrial waste in the production cycle. This type of waste is capable of binding man-made CO2 and transforming it into stable insoluble compounds, having binder properties. The optimum technological parameters of the forced carbonisation of the nepheline slime binder was determined by the mathematical planning of the experiment. The novelty of the research is the expansion of the secondary raw material base that can bind the man-made CO2 with obtaining the construction products of appropriate quality. It was revealed that the process of active CO2 absorption by the minerals of nepheline slime is observed in the first 120 min of the forced carbonization. Immediately after carbonisation, the resulting material develops compressive strength up to 57.64 MPa, and at the subsequent hydration within 28 days this figure increases to 68.71 MPa. Calcium carbonate is the main binder that determines the high mechanical properties of the samples. During the subsequent hydration of the uncoated belite, gel-like products are formed, which additionally harden the carbonised matrix. Thus, after the forced carbonisation and the following 28 days of hardening, the material with compressive strength in the range 4.38–68.71 MPa and flexural strength of 3.1–8.9 MPa was obtained. This material was characterised by water absorption by mass in the range of 13.9–23.3% and the average density of 1640–1886 kg/m3. The softening coefficient of the material was 0.51–0.99. The results obtained enables one to consider further prospects for research in this area, in terms of the introduction of additional technological parameters to study the process of forced carbonisation of nepheline slime.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2154
Author(s):  
Gye Hwa Shin ◽  
Jun Tae Kim

Curcumin nanosuspensions (Cur-NSs), chitosan-coated Cur-NSs (CS-Cur-NSs), and oligochitosan-coated Cur-NSs (OCS-Cur-NSs) were prepared by using an ultrasonic homogenization technique. The mean particle size of Cur-NSs was 210.9 nm and significantly (p < 0.05) increased to 368.8 nm by CS coating and decreased to 172.8 nm by OCS coating. Encapsulation efficiencies of Cur-NSs, CS-Cur-NSs, and OCS-Cur-NSs were 80.6%, 91.4%, and 88.5%, respectively. The mucin adsorption of Cur-NSs was steeply increased about 3–4 times by CS and OCS coating. Morphological changes of these NSs were studied using circular dichroism spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, and transmission electron microscopy (TEM). Thus, CS-Cur-NSs and OCS-Cur-NSs showed great potential as mucoadhesive nano-carriers for the efficient delivery of water insoluble compounds like curcumin to the gastrointestinal system.


Water ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 2912
Author(s):  
Ganesh L. Ghurye

The objective of this research study was to evaluate the feasibility of using a minimum liquid discharge (MLD) desalination approach as an alternate management option for unconventional produced waters (PWs) with a focus on minimizing the generation of solid waste. The feasibility of MLD was evaluated using OLI, a water chemistry software, to model thermal desalination of unconventional PWs from the Delaware Basin in New Mexico (NM). Desalination was theoretically terminated at an evaporation point before halite (NaCl) saturation in the residual brine. Results of this study showed that selectively targeting a subset of higher flow rate and lower TDS wells/centralized tank batteries (CTBs) could yield up to 76% recovery of distillate while generating minimal solid waste. Using a selective MLD approach did reduce the quantity of distillate recovered when compared with ZLD, and left a reduced volume of residual brine which has to be managed as a liquid waste. However, selective MLD also greatly reduced the amount of solid waste. The use of a ZLD approach yielded incrementally greater quantities of distillate but at the cost of large quantities of difficult-to-manage highly soluble waste. Simulation results showed that waste generated before NaCl precipitation was primarily composed of insoluble compounds such as calcite, barite and celestite, which can be disposed in conventional landfills. This study also found a simple empirical linear relationship between TDS and distillate recovery, thus allowing a non-expert to rapidly estimate potential distillate recovery for a given starting PW quality.


2021 ◽  
Vol 1043 ◽  
pp. 163-175
Author(s):  
Ekaterina Suraeva ◽  
Tatyana Elchishcheva ◽  
Dmitry Svetlov ◽  
Vasiliy Smirnov ◽  
Victor Afonin ◽  
...  

The structure of filled cementitious composite materials is formed as a result of hardening with the formation of a crystalline framework. The filler is involved in the building material crystal system structure formation. Chemically active fillers promote intensive release of hydration products that bind into insoluble compounds and increase the system stability. When developing the formulations for dry building mixtures, it is effective to use several fillers with different properties that complement each other, and biocidal additives increasing the materials resistance to environment effects formed by mold fungi. To create modified dry building mixtures based on cement binder, materials such as filler made of quartz sand of various fractions, fillers chrysotile and clinoptilolite and biocidal additives of the Teflex series were used. The composition with sand grains of 0.16–0.315 mm in size showed high strength properties in bending and compression. The introduction of chrysotile in an amount of 3% by weight of cement and quartz sand with a particle size of 0.16–0.315 mm increases the compressive and flexural strength by 7 and 13%, respectively, compared with the control composition. Clinoptilolite, introduced in an amount of 20% of the cement mass instead of one of the quartz sand fractions, increases the compressive strength of the composites up to 5%. The introduction of the Teflex series additives in the amount of at least 1% by weight of the binder ensures the composites’ fungal resistance. The additive “Teflex disinfectant” in an amount of at least 3% of the cement mass gives the composites fungicidal properties, the zone of no fungal growth on the nutrient solution near the infected samples is 4 mm.


Author(s):  
Christopher J. Hansen ◽  
Shajila Siricilla ◽  
Naoko Boatwright ◽  
Jackson H. Rogers ◽  
Melissa E. Kumi ◽  
...  

AbstractA great need exists to develop tocolytic and uterotonic drugs that combat poor, labor-related maternal and fetal outcomes. A widely utilized method to assess novel compounds for their tocolytic and uterotonic efficacy is the isometric organ bath contractility assay. Unfortunately, water-insoluble compounds can be difficult to test using the physiological, buffer-based, organ bath assay. Common methods for overcoming solubility issues include solvent variation, cosolvency, surfactant or complexion use, and emulsification. However, these options for drug delivery or formulation can impact tissue function. Therefore, the goal of this study was to evaluate the ability of common solvents, surfactants, cosolvents, and emulsions to adequately solubilize compounds in the organ bath assay without affecting mouse myometrial contractility. We found that acetone, acetonitrile, and ethanol had the least effect, while dimethylacetamide, ethyl acetate, and isopropanol displayed the greatest inhibition of myometrial contractility based on area under the contractile curve analyses. The minimum concentration of surfactants, cosolvents, and human serum albumin required to solubilize nifedipine, a current tocolytic drug, resulted in extensive bubbling in the organ bath assay, precluding their use. Finally, we report that an oil-in-water base emulsion containing no drug has no statistical effect beyond the control (water), while the drug emulsion yielded the same potency and efficacy as the freely solubilized drug.


Author(s):  
A.Yu. Kurbatov ◽  
E.N. Kuzin ◽  
Yu.M. Averina ◽  
M.A. Vetrova ◽  
A.V. Sitnikov

The paper aims to investigate hydrodynamic treatment processes of raw (artesian) groundwater to be used for household needs and drinking. The main advantage of hydrodynamic raw water treatment is that a single device, a so-called hydrodynamic vibration generator, is enough to perform the most important processing (deferrization, manganese removal, aeration) without any additional reactants. A hydrodynamic vibration generator contributes to accelerating mass exchange processes without using additional chemical reactants, solely by means of the kinetic energy inherent in the raw water flow undergoing treatment, which is generated when the hydrodynamic properties of the flow itself change dramatically. The generator by itself does not purify water; it processes raw water so as to derive insoluble products by recombining the forms in which the substances to be removed are found in the water, that is, by transforming dissolved manganese and iron compounds into insoluble compounds and decreasing carbon dioxide content in the water so as to precipitate insoluble calcium compounds. The resulting insoluble compounds are easy to remove via further processing in a ceramic membrane filtration system. Hydrodynamic vibration generator efficiency depends on many factors, which means that, when implementing hydrodynamic raw water treatment in real life, obtaining fundamental laws governing the treatment processes as functions of respective parametric characteristics is a necessary stage so as to ensure maximum efficiency. Our experiment confirmed that a phenomenon known as sonoluminescence occurs in raw water subjected to hydrodynamic treatment. We propose a monitoring technology indirectly confirming the efficiency of the hydrodynamic raw water treatment implemented, which is based on recording the sonoluminescence phenomenon via an acoustic technique


Author(s):  
Stefano Covelli ◽  
Elisa Petranich ◽  
Elena Pavoni ◽  
Sergio Signore

AbstractThe sediments in the Gulf of Trieste (northern Adriatic Sea, Italy) are contaminated by mercury (Hg) due to historic mining which took place in Idrija (Slovenia). Despite many studies having been done regarding Hg, no information is available on the potential impact of dredging required along the main channel approaching the Port of Monfalcone. Sixteen surface sediment samples were collected along the channel to determine both total Hg concentration and chemical species using the thermo-desorption (TD) technique. Six samples were also chosen to apply a selective sequential extraction (SSE). The TD technique showed the maximum Hg release approximately at 260 and 335°C, corresponding to metacinnabar (β-HgS) and cinnabar (α-HgS), respectively. The SSE demonstrated that Hg was mainly associated with poorly soluble or insoluble compounds (98.7%). A resuspension event over a limited period of time can be considered of negligible impact to the water column due to the scarce Hg mobility from sediments.


Author(s):  
M. D. Bakaeva ◽  
S. P. Chetverikov ◽  
D. V. Chetverikova ◽  
A. A. Kendzhieva

Herbicide-resistant strains of Pseudomonas and Achromobacter have been isolated. Theу are diazotrophic, can mobilize phosphorus from insoluble compounds and synthesize phytohormones in the presence of herbicides.


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