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Topic Review
Quercus suber and Cork By-Products
There is a drive within the cosmetic industry towards the development of more sustainable products, supported by consumer awareness of the environmental footprint. The cosmetic industry is rising to meet consumer demand by following practices, such as the use of by-products from agro-industrial waste. Quercus suber is a tree prevalent in the Mediterranean basin. The extraction of cork is considered sustainable, as this process does not harm the tree, and the amount of cork produced increases with the number of extractions. Beyond this, the cork industry produces by-products that are used to sustain the industry itself, such as cork powder, which is reused for generating energy. Additionally, cork and cork by-products contain bioactive compounds mainly with antioxidant activity that can be of use to the cosmetic industry, such as for antiaging, anti-acne, anti-inflammatory, and depigmenting cosmetic products.
  • 537
  • 30 May 2022
Topic Review
Carbon Capture, Utilization, and Storage (CCUS)
Greenhouse gas emission into the atmosphere is considered the main reason for the rise in Earth’s mean surface temperature. According to the Paris Agreement, to prevent the rise of the global average surface temperature beyond two degrees Celsius, global CO2 emissions must be cut substantially. While a transition to a net-zero emission scenario is envisioned by mid-century, carbon capture, utilization, and storage (CCUS) will play a crucial role in mitigating ongoing greenhouse gas emissions. Injection of CO2 into geological formations is a major pathway to enable large-scale storage. 
  • 537
  • 21 Apr 2023
Topic Review
Catalysts in Fischer-Tropsch Synthesis
With an increase in energy consumption globally, Fischer-Tropsch (FT) synthesis is a good alternative for producing fuels and chemicals from coal, natural gas or biomass. Among them, coal to liquids has been put into production in countries that have large coal reserves. In this process, Fe-based catalysts are commonly used due to their earth abundance, comparatively wide operation range and ready availability to handle low H2/CO ratio from coal. 
  • 514
  • 13 Jul 2023
Topic Review
Hydrometallurgy and Germanium Recovery from Secondary Resources
Though nowadays germanium do not reach the range of popularity than other metals, i.e. rare earth elements, its utility in target industries makes of it also a strategic metal. Though germanium can be found in a series of raw materials, the principal source for its recovery is from secondary wastes of the zinc industry, also, the recycle of germanium-bearing waste materials is becoming of interest. In this recovery the size of the target materials because the diffusion and reaction are to be considered, Hydrometallurgy is performing a key role to the successful achievement of this goal. The present work reviews the most recent applications (2023 and 2024 years) of hydrometallurgical operations on the recovery of germanium from different solid and liquid sources.  
  • 512
  • 30 Apr 2024
Topic Review
Electropolishing
Electropolishing of metal surfaces is a benign alternative to mechanical treatment. Ionic liquids are considered as green electrolytes for the electropolishing of metals. They demonstrate a number of advantages in comparison with acid aqueous solutions and other methods of producing smooth or mirror-like surfaces that are required by diverse applications (medical instruments, special equipment, implants and prostheses, etc.).
  • 507
  • 07 Jul 2021
Topic Review
Natural Polymers in Drug Delivery Systems
Natural polymers have received a great deal of interest for their potential use in the encapsulation and transportation of pharmaceuticals and other bioactive compounds for disease treatment. In this perspective, the drug delivery systems (DDS) constructed by representative natural polymers from animals (gelatin and hyaluronic acid), plants (pectin and starch), and microbes (Xanthan gum and Dextran) are provided. In order to enhance the efficiency of polymers in DDS by delivering the medicine to the right location, reducing the medication’s adverse effects on neighboring organs or tissues, and controlling the medication’s release to stop the cycle of over- and under-dosing, the incorporation of Fe3O4 magnetic nanoparticles with the polymers has engaged the most consideration due to their rare characteristics, such as easy separation, superparamagnetism, and high surface area. 
  • 507
  • 07 Feb 2023
Topic Review
Fe3O4-Based Nanocatalysts in Environmental Remediation and Cancer Treatment
Magnetite (Fe3O4) nanomaterials provide a possible way to achieve this goal, due to their magnetism, chemical stability, low toxicity, economic viability, etc. Therefore, Fe3O4-based materials are emerging as an important solid support to load heterogeneous catalysts and immobilize homogeneous catalysts. Moreover, the addition of magnetic character to catalysts will not only make their recovery much easier but also possibly endow catalysts with desirable properties, such as magnetothermal conversion, Lewis acid, mimetic enzyme activity, and Fenton activity.
  • 505
  • 04 May 2023
Topic Review
Prominent Pharmacological Activities of Pistacia lentiscus Polyphenols
Pistacia lentiscus (lentisk) is a plant species of the Anacardiaceae family. It is a medicinal plant that grows wild in the Mediterranean region. The plant P. lentiscus, which is used in traditional medicine, possesses pharmacological attributes and may offer significant potential as a therapeutic agent. The biological and therapeutic potentials of lentisk extracts have been evaluated in terms of antioxidant, antimicrobial, and anti-inflammatory activities. Most of these activities are related to the phenolic composition of this plant. It has been used in traditional medicine for the treatment of several diseases, such as for gastrointestinal diseases, eczema, and throat infections, due to its potent antioxidant, anti-inflammatory, and antimicrobial effects.
  • 501
  • 12 Jan 2023
Topic Review
H2 Antagonist
H2 antagonists, sometimes referred to as H2RAs and also called H2 blockers, are a class of medications that block the action of histamine at the histamine H2 receptors of the parietal cells in the stomach. This decreases the production of stomach acid. H2 antagonists can be used in the treatment of dyspepsia, peptic ulcers and gastroesophageal reflux disease. They have been surpassed by proton pump inhibitors (PPIs); the PPI omeprazole was found to be more effective at both healing and alleviating symptoms of ulcers and reflux oesophagitis than the H2 blockers ranitidine and cimetidine. H2 antagonists are a type of antihistamine, although in common use the term "antihistamine" is often reserved for H1 antagonists, which relieve allergic reactions. Like the H1 antagonists, some H2 antagonists function as inverse agonists rather than receptor antagonists, due to the constitutive activity of these receptors. The prototypical H2 antagonist, called cimetidine, was developed by Sir James Black at Smith, Kline & French – now GlaxoSmithKline – in the mid-to-late 1960s. It was first marketed in 1976 and sold under the trade name Tagamet, which became the first blockbuster drug. The use of quantitative structure-activity relationships (QSAR) led to the development of other agents – starting with ranitidine, first sold as Zantac, which has fewer adverse effects and drug interactions and is more potent. H2 blockers, which all end in "-tidine," are not the same as H1 receptor antagonists, which relieve allergy symptoms.
  • 489
  • 31 Oct 2022
Topic Review
Copper-Based Materials for Sustainable Environmental Applications
Copper-based nanomaterials have gained significant attention for their practical environmental applications due to their cost-effectiveness, thermal stability, selectivity, high activity, and wide availability. 
  • 487
  • 21 Jul 2023
Topic Review
Photoswitchable Zirconium MOF
UiO-66-NH2 is a metal–organic framework (MOF), which is constructed of zirconium and amino-terephthalate ions. Modification of MOFs with photochromic compounds allows managing their gas capacity and directing sorption-desorption processes. Photochromic molecules are able to reverse their configuration under UV‐light irradiation affecting available pore volume. The modification of UiO‐66‐NH2 with diarylethene molecules (DAE, 4‐(5‐Methoxy‐1,2‐dimethyl‐1H‐indol‐3‐yl)‐3‐(2,5‐dimethylthiophen‐3‐yl)‐4‐furan‐2,5‐dione) results in the formation of new photoswitchable material for light-driven H2 storage. Most of the DAE molecules inside of the UiO‐66‐pores had an open conformation after synthesis. However, the equilibrium was able to be shifted further toward an open conformation using visible light irradiation with a wavelength of 520 nm. Conversely, UV‐light with a wavelength of 450 nm initiated the transformation of the photoresponsive moieties inside of the pores to a closed modification. We have shown that this transformation could be used to stimulate hydrogen adsorption–desorption processes. Specifically, visible light irradiation increased the H2 capacity of modified MOF, while UV‐light decreased it. A similar hybrid material with DAE moieties in the UiO‐66 scaffold was applied for hydrogen storage for the first time. Additionally, the obtained results are promising for smart H2 storage that is able to be managed via light stimuli.
  • 485
  • 02 Dec 2021
Topic Review
Applications of Luminescent Materials in Visible Light Communication
The growing demand for faster data transference and communication allowed the development of faster and more efficient communication network-based technologies, with wider bandwidth capability, high resilience to electromagnetic radiation, and low latency for information travelling. To provide a suitable alternative to satisfy data transmission and consumption demand, wireless systems were established after studies on this topic. Visible light communication (VLC) processes were incorporated as interesting wireless approaches that make use of a wide frequency communication spectrum to reach higher bandwidth values and accelerate the speed of data/information transmission. For this aim, light converters, such as phosphor materials, are reported to efficiently convert blue light into green, yellow, and red emissions; however, long carrier lifetimes are achieved to enlarge the frequency bandwidth, thereby delaying the data transference rate.
  • 479
  • 28 Jun 2023
Topic Review
Silicon, Organic and Perovskite Solar Cells
The journey of photovoltaic (PV) cell technology is a testament to human ingenuity and the relentless pursuit of sustainable energy solutions. From the early days of solar energy exploration to the sophisticated systems of today, the evolution of PV cells has been marked by groundbreaking advancements in materials and manufacturing processes. The initial phase of solar cell development was characterized by the use of crystalline silicon, a material that has maintained its prominence due to its proven efficiency and durability. The progression from the initial 15% efficiency in the 1950s to the current levels nearing 28% epitomizes the significant strides that have been made in enhancing solar cell performance. This evolution is a clear indicator of how material advancements have been instrumental in propelling the solar industry forward.
  • 478
  • 12 Mar 2024
Topic Review
The Pathways to Create Containers for Bacteriophage Delivery
Antimicrobial resistance is a global public health threat. One of the possible ways to solve this problem is phage therapy, but the instability of bacteriophages hinders the development of this approach. A bacteriophage delivery system that stabilizes the phage is one of the possible solutions to this problem. 
  • 477
  • 23 Feb 2022
Topic Review
Squaraine-Based Fluorescent Materials
Squaraine dyes (SQs) are a peculiar class of cyanine dyes. One of the biggest structure differences between SQs and other types of cyanine dyes is that SQs contain an electron-deficient square ring at the center of the polymethine chain, leading to a quadrupolar donor-acceptor-donor (D-A-D) structure with a unique resonance-stabilized zwitterionic feature, as shown ina. In addition, the central square ring can make the polymethine chain rigid and planar to resist the photoisomerization and oxidation, and thus SQs intrinsically exhibit a greater stability over other cyanines.
  • 473
  • 27 May 2022
Topic Review
Enhance the Solvent Potential of Water
Water is considered the greenest solvent. Nonetheless, the water solubility of natural products is still an incredibly challenging issue. Indeed, it is nearly impossible to solubilize or to extract many natural products properly using solely water due to their low solubility in this solvent. 
  • 466
  • 09 Dec 2022
Topic Review
Carbon Dots in Electrochemical Biosensing Composites
Carbon dots (CDs) are zero-dimensional carbon nanomaterials that have been polymerized. CDs have been extensively used as biosensors. CDs are a subclass of nanoparticles, defined by a quasi-spherical morphology with a single unit with a characteristic size < 10 nm. CDs have been extensively used as electrochemical sensing composites due to their interesting chemical, electronic, and mechanical properties giving rise to increased performance.
  • 466
  • 10 May 2023
Topic Review Peer Reviewed
Formulation in Surfactant Systems: From-Winsor-to-HLDN
Formulation is an ancient concept, although the word has been used only recently. The first formulations made our civilization advance by inventing bronze, steel, and gunpowder; then, it was used in medieval alchemy. When chemistry became a science and with the golden age of organic synthesis, the second formulation period began. This made it possible to create new chemical species and new combinations “à la carte.” However, the research and developments were still carried out by trial and error. Finally, the third period of formulation history began after World War II, when the properties of a system were associated with its ingredients and the way they were assembled or combined. Therefore, the formulation and the systems’ phenomenology were related to the generation of some synergy to obtain a commercial product. Winsor’s formulation studies in the 1950s were enlightening for academy and industries that were studying empirically surfactant-oil-water (SOW) systems. One of its key characteristics was how the interfacial interaction of the adsorbed surfactant with oil and water phases could be equal by varying the physicochemical formulation of the system. Then, Hansen’s solubility parameter in the 1960s helped to reach a further understanding of the affinity of some substances to make them suitable to oil and water phases. In the 1970s, researchers such as Shinoda and Kunieda, and different groups working in Enhanced Oil Recovery (EOR), among them Schechter and Wade’s group at the University of Texas, made formulation become a science by using semiempirical correlations to attain specific characteristics in a system (e.g., low oil-water interfacial tension, formulation of a stable O/W or W/O emulsion, or high-performance solubilization in a bicontinuous microemulsion system at the so-called optimum formulation). Nowadays, over 40 years of studies with the hydrophilic-lipophilic deviation equation (HLD) have made it feasible for formulators to improve products in many different applications using surfactants to attain a target system using HLD in its original or its normalized form, i.e., HLDN. Thus, it can be said that there is still current progress being made towards an interdisciplinary applied science with numerical guidelines. In the present work, the state-of-the-art of formulation in multiphase systems containing two immiscible phases like oil and water, and therefore systems with heterogeneous or micro-heterogeneous interfaces, is discussed. Surfactants, from simple to complex or polymeric, are generally present in such systems to solve a wide variety of problems in many areas. Some significant cases are presented here as examples dealing with petroleum, foods, pharmaceutics, cosmetics, detergency, and other products occurring as dispersions, emulsions, or foams that we find in our everyday lives.
  • 464
  • 23 Sep 2022
Topic Review
Sol-Gel Materials for Electrochemical Applications
Modified electrodes for sensors and supercapacitors as well as anti-corrosion are described. Sol-gel synthesis expands the capabilities of technologists to obtain highly porous, homogeneous, and hybrid thin-film materials for supercapacitor electrode application. The widespread materials are transition metal oxides, but due to their low conductivity, they greatly impede the rate capability of electrochemical supercapacitors. The way to optimize their properties is the production of complex oxides or different composites. Among the new materials, a special place is occupied by perovskites and materials with an olivine-type structure, which can be easily obtained by the sol-gel method. The sol-gel coating process has demonstrated excellent chemical stability to advance the corrosion resistance of the various metal alloy substrates. 
  • 464
  • 29 Nov 2022
Topic Review
Photocatalytic Transformation of Biomass and Biomass Derived Compounds
Biomass and biomass-derived compounds have become an important alternative feedstock for chemical industry. They may replace fossil feedstocks such as mineral oil and related platform chemicals. These compounds may also be transformed conveniently into new innovative bioactive products, for example, for the medicinal or the agrochemical domain.
  • 464
  • 27 Jun 2023
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