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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.
  • 1.4K
  • 13 Dec 2022
Topic Review
Nanocomposites: Brief Overview
Nanocomposites are composite materials consisting of nanoscale building blocks and a matrix. Nanocomposites are materials composed of a polymer matrix reinforced with nanoparticles, typically with dimensions ranging from 1 to 100 nanometers. These nanoparticles can be made of various materials, such as metals, ceramics, and carbon-based materials, and they can be dispersed uniformly throughout the polymer matrix They have unique properties that make them useful in a wide range of applications, including water remediation, energy storage and conversion, packaging, sensors, biomedicine, environmental monitoring, and coatings. The properties of nanocomposites can be tailored by controlling the size, shape, and composition of the nanoscale building blocks and the matrix material. Some of the key properties of nanocomposites include high surface area-to-volume ratio, improved mechanical properties, enhanced electrical and thermal conductivity, improved barrier properties, and biocompatibility. The study of nanocomposites is a rapidly growing field with many exciting opportunities for new and improved applications.These articles provide a comprehensive overview of the synthesis, structure, properties, and applications of nanocomposites, including their use in water remediation.
  • 1.4K
  • 23 Mar 2023
Topic Review
Biodiesel as Renewable Biofuel in Current Diesel Engines
Many countries are immersed in several strategies to reduce the carbon dioxide (CO2) emissions of internal combustion engines. One option is the substitution of these engines by electric and/or hydrogen engines. However, apart from the strategic and logistical difficulties associated with this change, the application of electric or hydrogen engines in heavy transport, e.g., trucks, shipping, and aircrafts, also presents technological difficulties in the short-medium term. In addition, the replacement of the current car fleet will take decades. This is why the use of biofuels is presented as the only viable alternative to diminishing CO2 emissions in the very near future. Nowadays, it is assumed that vegetable oils will be the main raw material for replacing fossil fuels in diesel engines.
  • 1.4K
  • 13 May 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.
  • 1.4K
  • 09 Oct 2021
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.
  • 1.4K
  • 02 Mar 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.
  • 1.4K
  • 23 Nov 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.
  • 1.4K
  • 30 Aug 2022
Topic Review
Kaolinitic Raw Materials for Ceramics
Eight kaolinitic materials from the Lokoundje River at Kribi were sampled and investigated for their physical, chemical, mineralogical and thermal characteristics in order to evaluate their potential suitability as raw materials in ceramics. The Lokoundje kaolinitic materials are clayey to silty clayey and are predominantly composed of kaolinite and quartz. The alkali (Na2O + K2O) content ranges between 1 and 2.5 wt.%; these low values do not favor vitrification of the ceramics but may be improved through flux amendment. The presence of goethite in some samples limits their utilization in white ceramics. The minerals content, color, metallic sound, cohesion, linear shrinkage, flexural strength, bulk density, water absorption and microstructure were determined. The XRD data reveal that kaolinite and goethite were transformed, respectively, into mullite and hematite. The colors of the fired products are characteristic of their mineral assemblage. The metallic sound is indicative of low vitrification which is confirmed by the presence of cracks due to low flux contents. The cohesion is good to very good, due to the abundance of kaolinite. The physicomechanical properties increase with temperature as well as densification. The geochemical data show that the Lokoundje alluvial clays are suitable for the manufacture of white stoneware tiles. 
  • 1.4K
  • 09 Jul 2021
Topic Review
Use of Plant Extracts as Sustainable Corrosion Inhibitors
Corrosion inhibitors have traditionally been utilised to protect copper alloy sculptures from corrosion despite the recognised environmental and human health risks. Knowing the associated toxicity, ongoing extensive research seeks alternative substances for corrosion reduction, giving rise to the emergence of green inhibitors. In this pursuit, plant extract inhibitors have gained attention, particularly in the heritage field. 
  • 1.4K
  • 28 Feb 2024
Topic Review
SBA-15 synthesis variables
SBA-15 synthetized at different values of time and temperature of the hydrothermal treatment were mixture with tobacco in order to determine the capacity of reduction of toxic and carcirogenic compounds on tobacco smoke. The effect of temperature is not significative but time presents a remarked effect. And a parameter not frequently studied, the aparent density, has been shown the most relevant relation with the results on smoking experimentos. Finally, the effect of reduce the supernatant liquor also has been studied and the results have shown that the material properties remain practically unchanged.
  • 1.4K
  • 01 Nov 2020
Topic Review
Chitosan Nanostructures
Chitosan (CS) is a natural polymer with a positive charge, a deacetylated derivative of chitin. Chitosan nanostructures (nano-CS) have received increasing interest due to their potential applications and remarkable properties. 
  • 1.4K
  • 04 Nov 2021
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.
  • 1.4K
  • 14 Sep 2022
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.
  • 1.3K
  • 19 Apr 2022
Topic Review
Sol-Gel and Layer-by-Layer Coatings
The use of urface-engineered coatings for the fire protection of cotton fabrics is continously growing. In this context, two main approaches have been extensively investigated, namely sol-gel derived coatings and layer-by-layer assemblies. These approaches are both capable of providing treated fabrics with outstanding flame-retardant features, when exposed to a flame or an irradiative heat flux.  This review work aims at discussing the recent progresse with respect to both strategies, highlighting current limitations, open challenges, and possible further developments.
  • 1.3K
  • 01 Nov 2020
Topic Review
Molecular Mechanisms of OER for Artificial Photosynthesis
Addressing the global environmental problem of water splitting to produce hydrogen fuel by solar energy is receiving so much attention. In water splitting, the essential problem to solve is the development of efficient catalysts for oxygen production. In the generation of hydrogen by water splitting, molecular oxygen should be evolved at the same time. However, it is not so easy to artificially achieve photosynthetic oxygen generation by developing novel systems in a short period of time, which took one billion years in the natural world. The oxidation of water to produce oxygen, i.e., oxygen evolution reaction (OER), involves transfers of four electrons and four protons, while the reduction of water to produce hydrogen, i.e., hydrogen evolution reaction (HER), is a reaction of two electrons and two protons.
  • 1.3K
  • 06 Dec 2023
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.
  • 1.3K
  • 07 Feb 2022
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.
  • 1.3K
  • 19 Oct 2020
Topic Review
2D Nanomaterials for Optical Limiting
Due to the outstanding physical, chemical, electronic, and optical properties, ultra-thin 2D materials can be potentially utilized in a wide spectrum of applications, including catalysis, energy storage, sensors, biomedicine and electronics/optoelectronics, etc. 
  • 1.3K
  • 18 Nov 2021
Topic Review
Ambient Mass Spectrometry Imaging and Its Applications
Ambient mass spectrometry imaging (AMSI) has attracted much attention in recent years. As a kind of unlabeled molecular imaging technique, AMSI can enable in situ visualization of a large number of compounds in biological tissue sections in ambient conditions. In this review, the developments of various AMSI techniques are discussed according to one-step and two-step ionization strategies. In addition, recent applications of AMSI for lipid and metabolite analysis (from 2016 to 2021) in disease diagnosis, animal model research, plant science, drug metabolism and toxicology research, etc., are summarized. Finally, further perspectives of AMSI in spatial resolution, sensitivity, quantitative ability, convenience and software development are proposed. 
  • 1.3K
  • 29 Mar 2022
Topic Review
Photocatalytic Desulfurization
Desulfurization of fuels such as diesel, gasoline, kerosene, and jet fuel has been a challenging operation and remains critical to the petrochemical industry. The main naturally occurring sulfur-containing organic compounds (SCCs) are sulfides, disulfides, mercaptans, thiophene (Th) and its derivatives (benzothiophene (BT), dibenzothiophenes (DBTs), 4-methylbenzothiophene (4-MBT), 4,6-dimethyldibenzothiophene (4,6-DMDBT), 3,7-dimethyldibenzothiophene (3,7-DMDBT), and 2,8-dimethyldibenzothiophene (2,8-DMDBT)). The presence of these SCCs in fuels is undesirable since they create problems during refining, namely deactivation of some catalysts and corrosion of equipment. Moreover, sulfur compounds release toxic SOx and cause severe environmental problems: water and air pollution, global warming, ecological instability, as well as the harmful impact on living organisms. Many countries (USA, European Union, Japan, China and so on) have introduced strict standards to limit the content of sulfur in fuels to 10 ppm.
  • 1.3K
  • 23 Sep 2022
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