Influence of potential range selection on the SnS@C/rGO anodes in potassium ion battery

The Prussian Blue analogue K2−δMn[Fe(CN)6]1−ɣ∙nH2O is regarded as a key candidate for potassium-ion battery positive electrode materials due to its high specific capacity and redox potential, easy scalability, and low cost. However, various intrinsic defects, such as water in the crystal lattice, can drastically affect electrochemical performance. In this work, we varied the water content in K2−δMn[Fe(CN)6]1−ɣ∙nH2O by using a vacuum/air drying procedure and investigated its effect on the crystal structure, chemical composition and electrochemical properties. The crystal structure of K2−δMn[Fe(CN)6]1−ɣ∙nH2O was, for the first time, Rietveld-refined, based on neutron powder diffraction data at 10 and 300 K, suggesting a new structural model with the Pc space group in accordance with Mössbauer spectroscopy. The chemical composition was characterized by thermogravimetric analysis combined with mass spectroscopy, scanning transmission electron microscopy microanalysis and infrared spectroscopy. Nanosized cathode materials delivered electrochemical specific capacities of 130–134 mAh g−1 at 30 mA g−1 (C/5) in the 2.5–4.5 V (vs. K+/K) potential range. Diffusion coefficients determined by potentiostatic intermittent titration in a three-electrode cell reached 10−13 cm2 s−1 after full potassium extraction. It was shown that drying triggers no significant changes in crystal structure, iron oxidation state or electrochemical performance, though the water level clearly decreased from the pristine to air- and vacuum-dried samples.

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Myrsinane and related diterpenes from Euphorbia falcata with selective potassium ion channel activity

Planta Medica ◽

10.1055/s-0035-1565539 ◽

2015 ◽

Vol 81 (16) ◽

Author(s):

A Vasas ◽

P Orvos ◽

L Tálosi ◽

P Forgo ◽

G Pinke ◽

...

Keyword(s):

Ion Channel ◽

Potassium Ion ◽

Channel Activity ◽

Potassium Ion Channel

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Corrosion monitoring and root cause identification in high solids concentrators

TAPPI Journal ◽

10.32964/tj15.7.467 ◽

2016 ◽

Vol 15 (7) ◽

pp. 467-477

Author(s):

PASI NIEMELAINEN ◽

MARTTI PULLIAINEN ◽

JARMO KAHALA ◽

SAMPO LUUKKAINEN

Keyword(s):

Paper Industry ◽

Black Liquor ◽

Construction Materials ◽

Open Circuit ◽

Process Conditions ◽

Potential Range ◽

Corrosion Monitoring ◽

General Corrosion ◽

High Solids ◽

Passive Area

Black liquor high solids (about 80%) concentrators have often been found to suffer from aggressive corrosion. In particular, the first and second effect bodies are susceptible to corrosion attacks resulting in tube leaks and wall thinning, which limit the availability and lifetime of evaporator lines. Corrosion dynamics and construction materials have been studied extensively within the pulp and paper industry to understand the corrosion process. However, it has been challenging to identify root causes for corrosion, which has limited proactive measures to minimize corrosion damage. Corrosion of the first phase concentrator was studied by defining the potential regions for passive area, stress corrosion cracking, pitting corrosion, and general corrosion. This was achieved by using a technique called polarization scan that reveals ranges for the passive area in which the equipment is naturally protected against corrosion. The open circuit potential, also known as corrosion potential, and linear polarization resistance of the metal were monitored online, which allowed for definition of corrosion risks for stainless steel 304L and duplex stainless steels 2205 and SAF 2906. An online temperature measurement added insight to the analysis. A process diagnostics tool was used to identify root causes of the corrosion attacks. Many of the root causes were related to process conditions triggering corrosion. Once the metal surface was activated, it was difficult to repassivate the metal naturally unless a sufficient potential range was reached.

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Modeling drive wheels of hoisting machines with rubber cables

MINING INFORMATIONAL AND ANALYTICAL BULLETIN ◽

10.25018/0236-1493-2020-6-0-105-114 ◽

2020 ◽

pp. 105-114

Author(s):

V. E. Perekutnev ◽

V. V. Zotov

Keyword(s):

Stress State ◽

Safety Factor ◽

Numerical Models ◽

Design Parameters ◽

Potential Range ◽

Capital Costs ◽

Reducing Gear ◽

Reduce Risk ◽

Steel Cables ◽

Sidewall Surface

Upgrading of hoisting machines aims to improve their performance, to reduce risk of accidents, and to cut down operational and capital costs. One of the redesign solutions is replacement of steel cables by rubber cables. This novation can extend life of pulling members, decrease diameters of drive and guide wheels and, consequently, elements of the whole hoisting machines: rotor, reducing gear, motor. This engineering novation needs re-designing of hoisting machines; thus, the new design should be validated, in particular, strength characteristics of the machine members. This article considers a drive wheel of a hoisting machine with a pulling belt. In order to justify the potential range of design parameters with regard to safety factor, the numerical models of different-design drive wheels are developed and their operation with pulling belt (rubber cable) is simulated in the SolidWorks environment. The data on the stress state of the wheel elements are analyzed, the most loaded points are identified, and the maximal stresses on the sidewall surface and in the spokes of wheels of different designs are plotted.

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Biocompatibility of Silver Nano Bio-conjugates from Vitis vinifera Seeds and its Major Component Resveratrol

International Journal of Drug Delivery Technology ◽

10.25258/ijddt.v6i3.8896 ◽

2016 ◽

Vol 6 (3) ◽

Author(s):

R. Preethi ◽

P. Padma

Keyword(s):

Zeta Potential ◽

Vitis Vinifera ◽

Silver Ions ◽

Seed Extract ◽

Polydispersity Index ◽

Potential Range ◽

Visible Spectroscopy ◽

Grape Seeds ◽

X Ray ◽

Uv Visible

The study focused on the green synthesis of silver nanobioconjugates (AgNPs) from phenolic-rich fruit source, Vitis vinifera seed extract and its major component phenolic, resveratrol respectively. Sunlight exposure for 20 minutes was the method of choice for the synthesis of AgNPs of the extract as well as the phenolic, resveratrol. The synthesized nanobioconjugates were characterized using UV-Visible spectroscopy, Transmission electron microscopy (TEM), Energy dispersive X-ray analysis (EDAX), X-ray diffraction (XRD), Polydispersity index, Zeta potential and Fourier transform infrared spectroscopy (FTIR). The reduction of silver ions was confirmed by UV-visible spectroscopy with peaks at 440nm for both nanobioconjugates synthesized from seed extract and compound. The nanobioconjugates showed the spherical in shape with 14-35nm in size and crystalline in nature. The conjugates are well dispersed with 0.301 and 0.287 polydispersity index and the zeta potential range at -13.6 and -14.3mV for stability. The FTRI data proved that the components in grape seeds act as good reductants and stabilizers for the silver nanobioconjugate synthesis. All the synthesized nanobioconjugates exhibited steady and sustained release of the medicinal components conjugated, proving their druggability, and were biocompatible with human cells, demonstrating their safety. The findings of the study validate the anticancer properties of silver nanobioconjugates of Vitis vinifera and its active component resveratrol.

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