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Topic Review
Liquid Chromatography Separation Mechanism
Separation is a critical process to isolate a particular compound, whether it is a natural product or a synthetic product. Studies of a compound’s characteristics and elucidation structure provides reliable results for pure compounds because there is no interference from other compounds. The primary source of difficulty in a separation process is the high similarity between two or more compounds, such as racemic and homologous mixtures. Liquid chromatography has proven to be an effective solution to those problems. The key to liquid chromatography separation is a sustainable retention and elution process. Stationary phases are essential for separating compounds in liquid chromatography. Various liquid chromatography columns of both preparative and quantitative types have been used and continue to develop. This research will discuss the separation mechanism in liquid chromatography.
  • 1.0K
  • 02 Mar 2022
Topic Review
Development Aspects for Practical Non-aqueous Redox-Flow Batteries
Redox-flow cells can be divided into four basic types: all-liquid redox-flow batteries (ALRFBs), semi-solid redox-flow batteries (SSRFBs), hybrid redox-flow batteries (HRFBs), and single-flow batteries (SFB). These four basic types can be further classified by their cell separation techniques and membrane setups. They range from having no separation membrane to having up to three separation membranes in parallel.
  • 1.0K
  • 20 Feb 2023
Topic Review
Formulation of Marketing Strategies for Cultured Meat
Existing conventional meat production systems have negative environmental effects, coupled with growing public health concerns. Furthermore, growing population has continued to increase the consumer demand for meat. Research suggested the utilization of cultured meat (CUME) grown from animal cells without encompassing the slaughtering process. Additional benefits of CUME include being environmentally friendly, with lower production of greenhouse gases, reduced land, and water usage. Studies were conducted to determine the overall consumer acceptability of CUME. Studies have also elaborated that wide-scale adoption of CUME is dependent on a multitude of factors, including regulatory bodies, economic availability, religion, and media perception of CUME.
  • 1.0K
  • 14 Sep 2022
Topic Review
Ni-Based Bimetallic Catalysts
Metallic Ni shows high activity for a variety of hydrogenation reactions due to its intrinsically high capability for H2 activation, but it suffers from low chemoselectivity for target products when two or more reactive functional groups are present on one molecule. Modification by other metals changes the geometric and electronic structures of the monometallic Ni catalyst, providing an opportunity to design Ni-based bimetallic catalysts with improved activity, chemoselectivity, and durability.
  • 1.0K
  • 07 Feb 2022
Topic Review
Catalytic Activity of Zeolite
Zeolites are microporous aluminosilicates with high surface area and crystallinity. They have been widely applied in many different fields, such as gas storage, water treatment, biomass upgrading, and oil refining, because of their strong acidity, excellent catalytic activity, shape selectivity, and hydrothermal stability. In the past decades, one of the most important applications of zeolites is in fluidized catalytic cracking (FCC) in the petrochemical industry, which accounts for more than 95% of the global zeolite catalyst consumption. It is reported that 400 million tons of olefins are produced annually, and about 59% of olefins are produced by FCC units. Light olefins are critical building blocks in the petrochemical industry, and the demand for olefins and their derivatives has continuously increased over the last decade. Therefore, it is important to understand how to improve the catalytic performance of zeolites. Studies have shown that the performance of zeolite catalysts for cracking reactions is determined by various factors, including the porous size and composition, e.g., the Si/Al ratio and the presence of other heteroatoms or extra-framework aluminum (EFAL) species. Since the range of possible combinations of zeolite structures and compositions is exceedingly large, it is highly desirable to understand the effects of zeolite topology and composition on hydrocarbon cracking in order to improve their activity and selectivity to desired products.
  • 1.0K
  • 09 Oct 2021
Topic Review
Molecular Sensing with Hyperpolarized 129Xe
Hyperpolarized noble gases have been used early on in applications for sensitivity enhanced NMR. 129Xe has been explored for various applications because it can be used beyond the gas-driven examination of void spaces. Its solubility in aqueous solutions and its affinity for hydrophobic binding pockets allows "functionalization" through combination with host structures that bind one or multiple gas atoms. Moreover, the transient nature of gas binding in such hosts allows the combination with another signal enhancement technique, namely chemical exchange saturation transfer (CEST). Different systems have been investigated for implementing various types of so-called Xe biosensors where the gas binds to a targeted host to address molecular markers or to sense biophysical parameters.
  • 1.0K
  • 19 Oct 2020
Topic Review
Transition Metal Oxide Electrode Materials
The rising use of nonrenewable fossil fuels in recent decades has put human existence in grave danger. As a result, it is imperative to design environmentally friendly and cost-effective energy storage devices. Supercapacitors are a promising energy device because of their high power density, outstanding cycle stability, and quick charge/discharge process. However, supercapacitors' energy density is still lower than that of conventional batteries'. Supercapacitors' electrochemical performance is heavily influenced by the electrode materials, as is well-known to everyone.
  • 1.0K
  • 19 Apr 2022
Topic Review
Current Challenges and Perspectives for Biomass Catalytic Pyrolysis
Lignocellulosic biomass is an excellent alternative of fossil source owing to the fact that it is low-cost, plentiful and environmentally friendly. Through pyrolysis, lignocellulosic biomass can be converted into the potential precusor of liquid fuel or platform chemicals. Therefore, the detailed knowledge and mechanism about biomass conversion should be overviewed and concluded. We have reviewed several factors which impact the conversion of biomass, including the properties of biomass, operational parameters of catalytic pyrolysis and different types of pyrolysis equipment. Meantime, some perspectives for future development have been proposed in the end.
  • 1.0K
  • 13 Dec 2022
Topic Review
Insight on Mercapto-Coumarins
Mercapto (or sulfanyl)-coumarins are heterocycles of great interest in the development of valuable active structures in material and biological domains. They represent a highly exploitable class of compounds that open many possibilities for further chemical transformations.
  • 1.0K
  • 07 Apr 2022
Topic Review
Ionic-Liquid-Based Materials for Protein-related Applications
Supported ionic liquids (SILs) have been investigated as alternative supports for enzymes in biocatalysis and as new supports in preparative liquid chromatography for the purification of high-value proteins and enzymes. SILs are materials in which ionic liquids are introduced to modify the surface and properties of materials, e.g. as ligands covalently bond or physiosorbed.
  • 1.0K
  • 23 Nov 2021
Topic Review
CRM for Additive Manufacturing
The term “critical raw materials” (CRMs) refers to various metals and nonmetals that are crucial to Europe’s economic progress. Modern technologies enabling effective use and recyclability of CRMs are in critical demand for the EU industries. The use of CRMs, especially in the fields of biomedicine, aerospace, electric vehicles, and energy applications, is almost irreplaceable. Additive manufacturing (also referred to as 3D printing) is one of the key enabling technologies in the field of manufacturing which underpins the Fourth Industrial Revolution. 3D printing not only suppresses waste but also provides an efficient buy-to-fly ratio and possesses the potential to entirely change supply and distribution chains, significantly reducing costs and revolutionizing all logistics. This review provides comprehensive new insights into CRM-containing materials processed by modern additive manufacturing techniques and outlines the potential for increasing the efficiency of CRMs utilization and reducing the dependence on CRMs through wider industrial incorporation of AM and specifics of powder bed AM methods making them prime candidates for such developments.
  • 1.0K
  • 05 May 2021
Topic Review
Non-Titania Based Semiconductor Hetero-Nanoarchitectures
Plasmonic photocatalysts combining metallic nanoparticles and semiconductors have been aimed as versatile alternatives to drive light-assisted catalytic chemical reactions beyond the ultraviolet (UV) regions, and overcome one of the major drawbacks of the most exploited photocatalysts (TiO2 or ZnO). The strong size and morphology dependence of metallic nanostructures to tune their visible to near-infrared (vis-NIR) light harvesting capabilities has been combined with the design of a wide variety of architectures for the semiconductor supports to promote the selective activity of specific crystallographic facets. The search for efficient heterojunctions has been subjected to numerous studies, especially those involving gold nanostructures and titania semiconductors. In the present review, we paid special attention to the most recent advances in the design of gold-semiconductor hetero-nanostructures including emerging metal oxides such as cerium oxide or copper oxide (CeO2 or Cu2O) or metal chalcogenides such as copper sulfide or cadmium sulfides (CuS or CdS). These alternative hybrid materials were thoroughly built in past years to target research fields of strong impact, such as solar energy conversion, water splitting, environmental chemistry, or nanomedicine.
  • 996
  • 15 Apr 2021
Topic Review
Adsorption Effect Modification of Lithium–Sulfur Batteries
Lithium–sulfur batteries (LSBs) have high theoretical specific capacity (1675 mAh g−1) and high energy density (2600 Wh kg−1), and the cathode sulfur is low cost, abundant, and environmentally friendly. The “shuttle effect” refers to the phenomenon that Li2Sx (4 ≤ x ≤ 8) produced by the positive electrode diffuses to the negative electrode during the charging and discharging process, and is reduced to solid Li2S2/Li2S on the negative electrode surface and attached to the negative electrode.
  • 995
  • 30 Aug 2022
Topic Review
Nanofilms
Nanofilms are thin films that are composed of nanoscale materials and have thicknesses typically ranging from a few nanometers to a few hundred nanometers. Nanofilms have unique properties that make them useful in a wide range of applications, including electronics, biomedicine, manufacturing, food, surface protection, and environmental protection. Nanofilms can be made from a variety of materials, including metals, ceramics, polymers, and composites. They can be designed with specific properties, such as high surface area, improved mechanical and chemical stability, and tailored optical and electrical properties. These unique properties of nanofilms make them useful in a wide range of applications.
  • 992
  • 06 Feb 2023
Topic Review
Hydrogels Combined with Silver Nanoparticles against Antimicrobial Resistance
The development of multidrug-resistant (MDR) microorganisms has increased dramatically as a natural consequence of the misuse and overuse of antimicrobials. The World Health Organization (WHO) recognizes that this is one of the top ten global public health threats facing humanity today, demanding urgent multisectoral action. In this sense, metallic nanoparticles (such as silver nanoparticles) have emerged as promising alternatives due to their outstanding antibacterial and antibiofilm properties. The efficient delivery of the nanoparticles (NPs) is also a matter of concern, and studies have demonstrated that hydrogels present an excellent ability to perform this task.
  • 982
  • 03 Feb 2023
Topic Review
Impact of Wort Amino Acids on Beer Flavour
The process by which beer is brewed has not changed significantly since its discovery thousands of years ago. Grain is malted, dried, crushed and mixed with hot water to produce wort. Yeast is added to the sweet, viscous wort, after which fermentation occurs. The biochemical events that occur during fermentation reflect the genotype of the yeast strain used, and its phenotypic expression is influenced by the composition of the wort and the conditions established in the fermenting vessel. Although wort is complex and not completely characterized, its content in amino acids indubitably affects the production of some minor metabolic products of fermentation which contribute to the flavour of beer. 
  • 975
  • 29 May 2023
Topic Review
Plant-Derived Metal Nanoparticles
Plant-derived metal nanoparticles (PDMNPs) have gained considerable interest because of their tremendous and remarkable potential as therapeutic agents as well as development of less expensive, safer, and easier biomedical equipment. PDMNPs are synthesized from metal salts or oxides by using plant extracts because plants have diversified bioactive compounds that can act as reducing and stabilizing agents at the time of nanoparticle synthesis. Besides, PDMNPs take advantages over the nanoparticles synthesized by other methods because of their low cost, environmental friendliness, and sustainability. 
  • 974
  • 23 Mar 2023
Topic Review
Seaweeds Compounds
Seaweeds’ compounds present important qualities for cosmetic application, such as low cytotoxicity and low allergens content. Several seaweeds’ molecules already demonstrated a high potential as a cosmetic active ingredient (such as, mycosporine-like amino acids, fucoidan, pigments, phenolic compounds) or as a key element for the products consistency (agar, alginate, carrageenan). Moreover, it focuses on the ecological and sustainable scope of seaweed exploitation to guarantee a safe source of ingredients for the cosmetic industry and consumers.
  • 968
  • 17 Jan 2022
Topic Review
Metal Phosphates and Pyrophosphates as Proton Conductors
It is about the progress in metal phosphate structural chemistry focused on proton conductivity properties. Attention is paid to structure–property relationships, which ultimately determine the potential use of metal phosphates and derivatives in devices relying on proton conduction. The origin of their conducting properties, including both intrinsic and extrinsic conductivity, is rationalized in terms of distinctive structural features and the presence of specific proton carriers or the factors involved in the formation of extended hydrogen-bond networks.
  • 960
  • 19 Apr 2022
Topic Review
Molecular Iodine Capture by Covalent Organic Frameworks
Covalent organic frameworks (COFs) are a class of extended crystalline porous polymers that possess unique architectures with high surface areas, long-range order, and permanent porosity. It is known that the possible radioactive iodine species in the environment are iodate (IO3−), molecular iodine (I2), and organic iodine species (e.g., methyl iodide (CH3I) and ethyl iodide (CH3CH2I)). Different iodine species need to be handled in different ways.
  • 958
  • 14 Feb 2023
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