scholarly journals Nanomineralogy as a new dimension in understanding elusive geochemical processes in soils: The case of low-solubility-index elements

Geology ◽  
2016 ◽  
Vol 44 (7) ◽  
pp. 515-518 ◽  
Author(s):  
Michael Schindler ◽  
Michael F. Hochella
2016 ◽  
Vol 2 (2) ◽  
pp. 91-95
Author(s):  
Neelima Rani T ◽  
Pavani A ◽  
Sobhita Rani P ◽  
Srilakshmi N

This study aims to formulate solid dispersions (SDs) of Simvastatin (SIM) to improve the aqueous solubility, dissolution rate and to facilitate faster onset of action. Simvastatin is a BCS class II drug having low solubility & therefore low oral bioavailability. In the present study, SDs of simvastatin different drug-carrier ratios were prepared by kneading method. The results showed that simvastatin solubility & dissolution rate enhanced with polymer SSG in the ratio 1:7 due to increase in wetting property or possibly may be due to change in crystallinity of the drug.


1986 ◽  
Vol 4 (1) ◽  
pp. 22-25 ◽  
Author(s):  
A.J. Laiche ◽  
V.E. Nash

Three woody landscape species, Rhododendron indica ‘President Clay’, Ligustrum sinense ‘variegata’, and Ilex crenata ‘compacta’, were grown in media prepared from fresh pine bark, pine bark with wood, and pine tree chips. Although media were variable in physical properties, all exhibited very high hydraulic conductivity and low water holding capacity. The capacity of these media materials to hold fertilizer elements was very low. Nitrogen, potassium, and phosphorus were rapidly removed by leaching while calciuum and magnesium were retained longer because of the low solubility of dolomitic limestone. Pine bark was the best growth media tested for all plant species. Pine bark with wood was less satisfactory than pine bark and growth was poorest in pine tree chips. More research is needed on the use of the organic amendments with greater amounts of wood before being widely used as organic components of growth media.


2020 ◽  
Author(s):  
wenda wu ◽  
Jian Luo ◽  
Fang Wang ◽  
Bing Yuan ◽  
Tianbiao Liu

Aqueous organic redox flow batteries (AORFBs) have become increasing attractive for scalable energy storage. However, it remains challenging to develop high voltage, powerful AORFBs because of the lack of catholytes with high redox potential. Herein, we report methyl viologen dibromide (<b>[MV]Br<sub>2</sub></b>) as a facile self-trapping, bipolar redox electrolyte material for pH neutral redox flow battery applications. The formation of the <b>[MV](Br<sub>3</sub>)<sub>2</sub></b> complex was computationally predicted and experimentally confirmed. The low solubility <b>[MV](Br<sub>3</sub>)<sub>2</sub></b> complex in the catholyte during the battery charge process not only mitigates the crossover of charged tribromide species (Br<sub>3</sub><sup>-</sup>) and addresses the toxicity concern of volatile bromine simultaneously. A 1.53 V bipolar MV/Br AORFB delivered outstanding battery performance at pH neutral conditions, specifically, 100% total capacity retention, 133 mW/cm<sup>2</sup> power density, and 60% energy efficiency at 40 mA/cm<sup>2</sup>.


Alloy Digest ◽  
1994 ◽  
Vol 43 (8) ◽  

Abstract NICROBRAZ 50 is a low-melting, free-flowing filter metal for honeycomb structures and thin-walled tube assemblies. It has low solubility. This datasheet provides information on composition, physical properties, and hardness. It also includes information on corrosion resistance as well as joining. Filing Code: Ni-460. Producer or source: Wall Colmonoy Corporation.


2020 ◽  
Vol 27 ◽  
Author(s):  
Antonis D. Tsiailanis ◽  
Andreas G. Tzakos ◽  
Thomas Mavromoustakos

: Drugs have to overcome numerous barriers to reach their desired therapeutic targets. In several cases drugs, especially the highly lipophilic molecules, suffer from low solubility and bioavailability and therefore their desired targeting is hampered. In addition, undesired metabolic products might be produced or off-targets could be recognized. Along these lines, nanopharmacology has provided new technological platforms, to overcome these boundaries. Specifically, numerous vehicle platforms such as cyclodextrins and calixarenes have been widely utilized to host lipophilic drugs such as antagonists of the angiotensin II AT1 receptor (AT1R), as well as quercetin and silibinin. The encapsulation of these drugs in supramolecules or other systems refines their solubility and metabolic stability, increases their selectivity and therefore decreases their effective dose and improves the therapeutic index. In this minireview we report on the formulations of Silibinin and AT1R antagonist candesartan in a 2-HP-β-cyclodextrin host molecule, which displayed enhanced cytotoxicity and increased silibinin’s and candesartan’s stability, respectively. Moreover we describe the encapsulation of quercetin in gold nanoparticles bearing a calixarene supramolecular host. Also the encapsulation of temozolomide in a calixarene nanocapsule has been described. Finally, we report on the activity enhancement that has been achieved upon using these formulations as well as the analytical and computational methods we used to characterize these formulations and explore the molecular interactions between the host and quest molecules.


2020 ◽  
Vol 8 (6) ◽  
pp. 437-451
Author(s):  
Malkiet Kaur ◽  
Gayatri Devi ◽  
Manju Nagpal ◽  
Manjinder Singh ◽  
Gitika A. Dhingra ◽  
...  

Background: Coronavirus has become a life-threatening disease and it is caused by severe acute respiratory syndrome (SARS). This new strain of coronavirus is not completely understood and to date, there is no treatment for coronavirus. Traditional ayurvedic medicines, mainly essential oils and Chinese herbs, have always played a vital role in the prevention and treatment of several epidemics and pandemics. In the meantime, guidelines of the ministry of AYUSH (Ayurveda, yoga, unani, siddha and homoepathy) include a traditional medicinal treatment for flu and fever and also recommended to boost immunity to prevent the spread of coronavirus. It is not possible to find which essential oil will offer the best level of protection. However, it is likely to assume that some essential oils are likely to offer a measurable level of defense in the same way they do with many other known viruses. Methods: Literature relevant to various essential oils having antiviral activity has been collected and compiled. Various nanocarriers of essential oils have also been stated. The database was collected using various search engines such as J-Gate, Google Scholar, Sci-Hub, PubMed, ScienceDirect, etc. Results: Essential oils contain active constituents such as phenolic compounds, terpenoids, alkaloids, phenyl propanoids, etc., which are responsible for their biological properties such as antiviral, antibacterial, antimicrobial, antioxidant activities and many more. However, the use of essential oils has always been limited due to poor solubility, solvent toxicity, volatility and low solubility. Many nanotechnology based carriers especially, liposomes, dendrimers, nanoparticles, nanoemulsion and microemulsion, etc. have been evidenced to overcome limitations associated with essential oils. Conclusion: Several essential oils possess potent antiviral activity and are characterized by fewer side effects and are safe for human use. The nanocarrier systems of these oils have proved the potential to treat viral and bacterial infections. Lay Summary: Current COVID-19 era demands traditional treatment for immunity boost up as support therapy. Traditional ayurvedic medicines, mainly essential oils and Chinese herbs, have always played a vital role in the prevention and treatment of several epidemics and pandemics. Therefore, authors have summarized various essential oils having antiviral activity in current manuscript. Various nanocarriers of essential oils have been reported. Essential oils contain active constituents such as phenolic compounds, terpenoids, alkaloids, phenyl propanoids, etc., which are responsible for their biological properties such as antiviral, antibacterial, antimicrobial, antioxidant activity. However, the use of essential oils has always been limited due to poor solubility, solvent toxicity, volatility and low solubility. Many nanotechnology based carriers especially, liposomes, dendrimers, nanoparticles, nanoemulsion and microemulsion, etc. have been evidenced to overcome limitations associated with essential oils. The nanocarrier systems of these oils have proved the potential to treat viral and bacterial infections.


Spurious kinks in estimated palaeogeotherms may result from small errors in the calibration of the geothermometers and geobarometers. New data indicate that the equilibrium solubility of alumina in enstatite is even less than shown by recent studies, and that the slopes (d T /d P ) of the isopleths of equal alumina content are steeper than hitherto believed. Consequently, pressures of equilibration estimated from current formulations of the orthopyroxene-garnet geobarometer will be too high at high temperatures (> 1200 °C) and too low at low temperatures.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mariusz Sojka ◽  
Adam Choiński ◽  
Mariusz Ptak ◽  
Marcin Siepak

AbstractThe objective of this study was to analyse spatial variability of the trace elements (TEs) and rare earth elements (REEs) concentration in lake bottom sediments in Bory Tucholskie National Park (BTNP); Poland. The following research questions were posed: which factors have a fundamental impact on the concentration and spatial variability of elements in bottom sediments, which of the elements can be considered as indicators of natural processes and which are related to anthropogenic sources. The research material was sediments samples collected from 19 lakes. The concentrations of 24 TEs and 14 REEs were determined. The analyses were carried out using the inductively coupled plasma mass spectrometry (ICP-QQQ). Cluster analysis and principal component analysis were used to determine the spatial variability of the TEs and REEs concentrations, indicate the elements that are the indicators of natural processes and identify potential anthropogenic sources of pollution. The geochemical background value (GBV) calculations were made using 13 different statistical methods. However, the contamination of bottom sediments was evaluated by means of the index of geo-accumulation, the enrichment factor, the pollution load index, and the metal pollution index. The BTNP area is unique because of its isolation from the inflow of pollutants from anthropogenic sources and a very stable land use structure over the last 200 years. This study shows high variability of TE and REE concentrations in lake sediments. The values of geochemical indices suggest low pollution of lakes bottom sediments. It was found that TEs originated mainly from geogenic sources. However, the concentrations of Li, Ni, Sc, Se, Be, Se, Ag, Re, Tl, Cd, Sb and U may be related to the impact of point sources found mainly in the Ostrowite Lake. Almost all REEs concentrations were strongly correlated and their presence was linked to with geochemical processes. The elements allowing to identify natural processes and anthropogenic pollution sources were Cr, Co, Cu, Ag, Cd, Zn, Bi, Re, Ba, Al and Rb in TEs group and Nd, Gd, Yb, Lu, Eu, Dy and Ce in REEs group. The analysis shows high spatial variability of TE and REE concentrations in lake sediments. The values of geochemical indices point to low pollution of lakes sediments. The anthropogenic sources only for two lakes had an impact on concentrations of selected TEs and REEs. The analyses allowed to identify elements among TEs and REEs documenting geochemical processes and those indicating anthropogenic sources of pollution.


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