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Topic Review
Multivariable Formulation of Surfactant-Oil-Water Systems
Surfactant-Oil-Water (SOW) systems are found in nature and synthetic products. They usually result in two immiscible phases, e.g., for two liquids, a water phase (often a brine), and an oily phase (which could be extremely complex as petroleum). Surfactant partitions between the two phases according to some physicochemical rules due to molecular interactions. There is a very particular formulation case in which SOW systems can form three immiscible phases, that is, two excess phases (water and oil) in equilibrium with a  so-called middle phase (because of an intermediate density that places it in the middle of a test tube). This middle phase is a so-called bicontinuous microemulsion which has no droplets dispersed in an external phase as a typical emulsion, but a complex single-phase structure similar to a disordered liquid crystal. When stirred, SOW systems can form multiple dispersed systems that can be described as macroemulsions or nanoemulsions depending on the drop size (O/W or W/O) or multiple emulsions (w/O/W or o/W/O) with droplets inside larger drops. Since the beginnings of the 20th century with Bancroft’s rule, the properties of these systems have been related to many thermodynamic variables, generally with one effect at a time. Nowadays, the generalized physicochemical concept of SOW systems with many formulation variables involved allows to make predictions in various application cases, even for very complex systems, as in enhanced oil recovery (EOR), crude oil dehydration, paints, foods, cosmetics and pharmaceutical formulations, that requires the control on 6-8 variables or even more. This is mainly because of the presence of mixtures of oils from linear alkanes to triglycerides or complex molecules perfumes, or a mixture of salts with cations from sodium to calcium or aluminum, and anions like chloride to phosphate. The complexity is even worse with mixtures of very different surface-active species, resulting in non-linear interactions.
  • 2.6K
  • 17 Aug 2021
Topic Review
Social Media Addiction
Social media addiction is a kind of psycho-social issues in the context of the increasing use of social media. What can be effective in reducing social media addiction, which causes social and economic problems, is an important issue today. It was determined that satisfaction with life had a mediation role in the effect of self-esteem and education level on social media addiction. Self-esteem and education level improved satisfaction with life, and increased satisfaction with life resulted in less social media addiction. These results demonstrate the importance of implementing specific practices based on self-esteem and education, especially for vulnerable groups, to minimize the problems that may arise with the excessive use of digital apps and social media.
  • 2.6K
  • 29 Sep 2021
Topic Review
Heavy Metals and Metalloids
The contamination of soil by heavy metals and metalloids is a worldwide problem due to the accumulation of these compounds in the environment, endangering human health, plants, and animals. Heavy metals and metalloids are normally present in nature, but the rise of industrialization has led to concentrations higher than the admissible ones. They are non-biodegradable and toxic, even at very low concentrations. Several techniques have been developed over the years: - physical remediation (e.g., washing, thermal desorption, solidification), - chemical remediation (e.g., adsorption, catalysis, precipitation/solubilization, electrokinetic methods), - biological remediation (e.g., biodegradation, phytoremediation, bioventing), and combined remediation (e.g., electrokinetic–microbial remediation; washing–microbial degradation).
  • 2.6K
  • 20 May 2021
Topic Review
Wireless Sensor Network
Wireless Sensor Network (WSN) is one of the most effective methods for many real-time applications, due to its compactness, cost-effectiveness, and ease of deployment. The function of the WSN is to monitor the field of interest, collect the data, and transmit it to the base station (Access point) for post-processing analysis.
  • 2.6K
  • 21 Jul 2022
Topic Review
1994 Scotland RAF Chinook Crash
On 2 June 1994, a Chinook helicopter of the Royal Air Force (RAF), serial number ZD576, crashed on the Mull of Kintyre, Scotland, in foggy conditions. The crash resulted in the deaths of all twenty-five passengers and four crew on board. Among the passengers were almost all the United Kingdom's senior Northern Ireland intelligence experts. The accident is the RAF's worst peacetime disaster. In 1995, an RAF board of inquiry ruled that it was impossible to establish the exact cause of the accident. This ruling was subsequently overturned by two senior reviewing officers, who stated the pilots were guilty of gross negligence for flying too fast and too low in thick fog. This finding proved to be controversial, especially in light of irregularities and technical issues surrounding the then-new Chinook HC.2 variant which were uncovered. A Parliamentary inquiry conducted in 2001 found the previous verdict of gross negligence on the part of the crew to be 'unjustified'. In 2011, an independent review of the crash cleared the crew of negligence.
  • 2.6K
  • 14 Nov 2022
Topic Review
Quinolones
Fluoroquinolones (FQs) are arguably among the most successful antibiotics of recent times. They have enjoyed over 30 years of clinical usage and become essential tools in the armoury of clinical treatments. FQs target the bacterial enzymes DNA gyrase and DNA topoisomerase IV, where they stabilise a covalent enzyme-DNA complex in which the DNA is cleaved in both strands. This leads to cell death and turns out to be a very effective way of killing bacteria. However, resistance to FQs is increasingly problematic, and alternative compounds are urgently needed.
  • 2.6K
  • 25 Dec 2020
Topic Review
ZnO Photocatalysts for the Treatment of Wastewater
The presence of contaminants in wastewater, surface water, groundwater, and drinking water is a serious threat to human and environmental health. Their toxic effects and resistance towards conventional water treatment methods have compelled the scientific community to search for an environmentally friendly method that could efficiently degrade toxic contaminants. In this regard, visible light active photocatalysts have proved to be efficient in eliminating a wide variety of water toxins. A plethora of research activities have been carried out and significant amounts of funds are spent on the monitoring and removal of water contaminants, but relatively little attention has been paid to the degradation of persistent water pollutants. In this regard, nanoparticles of doped ZnO are preferred options owing to their low recombination rate and excellent photocatalytic and antimicrobial activity under irradiation of solar light. 
  • 2.6K
  • 18 Feb 2022
Topic Review
Powered Hang Glider
A foot-launched powered hang glider (FLPHG), also called powered harness, nanolight, or hangmotor, is a powered hang glider harness with a motor and propeller in pusher configuration. An ordinary hang glider is used for its wing and control frame, and the pilot can foot-launch from a hill or from flat ground, needing a length of about a football field to get airborne, or much less if there is an oncoming breeze and no obstacles.
  • 2.6K
  • 04 Nov 2022
Topic Review
Metal Oxides for CO2 Capture and Conversion
Metal oxides are essential in determining the overpotential and product selectivity in the CO2reduction reactions (CO2RR). In contrast, developing efficient and stable metal oxides is a significant challenge that must be achieved to lower the production cost of fuels in the practical implementation of CO2RR technologies. 
  • 2.6K
  • 14 Apr 2022
Topic Review
MMP-13 in Osteoarthritis Treatment
Osteoarthritis (OA) is a common degenerative disease characterized by the destruction of articular cartilage and chronic inflammation of surrounding tissues. Matrix metalloproteinase-13 (MMP-13) is the primary MMP involved in cartilage degradation through its particular ability to cleave type II collagen. Hence, it is an attractive target for the treatment of OA.
  • 2.6K
  • 07 May 2021
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