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Topic Review
Polycaprolactone-Based Biocomposites
The developments within the topic of biomaterials has taken hold of researchers due to the mounting concern of current environmental pollution as well as scarcity resources. Amongst all compatible biomaterials, polycaprolactone (PCL) is deemed to be a great potential biomaterial, especially to the tissue engineering sector, due to its advantages, including its biocompatibility and low bioactivity exhibition. The commercialization of PCL is deemed as infant technology despite of all its advantages. This contributed to the disadvantages of PCL, including expensive, toxic, and complex.
  • 3.8K
  • 10 Feb 2022
Topic Review
Classical Nucleation Theory
Crystal nucleation determining the formation and assembly pathway of first organic materials is the central science of various scientific disciplines such as chemical, geochemical, biological, and synthetic materials. Classical nucleation theory (CNT)  applies to systems of small organic molecules with an emphasis on the molecular interpretation of nucleation kinetics. CNT holds that density fluctuations are concomitant with the development of crystalline order. In other words, a crystal nucleus has an identical structure to its bulk crystal. 
  • 3.8K
  • 22 Jul 2022
Topic Review
Petroleum
Petroleum, also known as crude oil, or simply oil, is a naturally occurring yellowish-black liquid mixture of mainly hydrocarbons, and is found in geological formations. The name petroleum covers both naturally occurring unprocessed crude oil and petroleum products that consist of refined crude oil. A fossil fuel, petroleum is formed when large quantities of dead organisms, mostly zooplankton and algae, are buried underneath sedimentary rock and subjected to both prolonged heat and pressure. Petroleum has mostly been recovered by oil drilling. Drilling is carried out after studies of structural geology, sedimentary basin analysis, and reservoir characterisation. Recent developments in technologies have also led to exploitation of other unconventional reserves such as oil sands and oil shale. Once extracted, oil is refined and separated, most easily by distillation, into numerous products for direct use or use in manufacturing, such as gasoline (petrol), diesel and kerosene to asphalt and chemical reagents used to make plastics, pesticides and pharmaceuticals. Petroleum is used in manufacturing a wide variety of materials, and it is estimated that the world consumes about 100 million barrels (16 million cubic metres) each day. Petroleum production can be extremely profitable and was important for economic development in the 20th century, with some countries, so called "oil states", gaining significant economic and international power because of their control of oil production. Petroleum exploitation has significant negative environmental and social consequences. Most significantly, extraction, refining and burning of petroleum fuels all release large quantities of greenhouse gases, so petroleum is one of the major contributors to climate change. Furthermore, parts of the petroleum industry actively suppressed science and policy that aimed to prevent the climate crisis. Other negative environmental effects include the environmental impacts of exploration and exploitation of petroleum reserves, such as oil spills, and air and water pollution at the sites of utilization. All of these environmental impacts have direct health consequences for humans. Additionally, oil has also been a source of conflict leading to both state-led-wars and other kinds of conflicts (for example, oil revenue funded the Islamic State). Production of petroleum is expected to reach peak oil before 2035 as global economies lower dependencies on petroleum as part of climate change mitigation and a transition towards renewable energy and electrification. This is expected to have significant economic impacts that stakeholders argue need to be anticipated by a just transition and addressing the stranded assets of the petroleum industry.
  • 3.8K
  • 21 Oct 2022
Topic Review
Overview of Polylactic Acid
Poly(lactic acid) (PLA) is an important polymer that is based on renewable biomass resources. Because of environmental issues, more renewable sources for polymers synthesis have been sought for industrial purposes.
  • 3.8K
  • 20 Jul 2022
Topic Review
Nanocellulose
Nanocellulose can be used to improve the mechanical properties of cementitious materials if a proper dosage is used. Nanocellulose can be used as a type of viscosity-modifying agent (VMA) in cementitious materials. Nanocellulose with a proper dosage can reduce the shrinkage of cementitious materials, especially with a low water-to-cement (w/c) ratio. Four types of nanocelluloses, including cellulose nanocrystal, cellulose nanofibril, bacterial cellulose, and cellulose filament, have been used in cementitious materials.
  • 3.7K
  • 25 Dec 2020
Topic Review
Catalyst Design via Colloidal Synthesis
Supported nanoparticles are commonly applied in heterogeneous catalysis. The catalytic performance of these solid catalysts is, for a given support, dependent on the nanoparticle size, shape, and composition, thus necessitating synthesis techniques that allow for preparing these materials with fine control over those properties. Such control can be exploited to deconvolute their effects on the catalyst’s performance, which is the basis for knowledge-driven catalyst design. In this regard, bottom-up synthesis procedures based on colloidal chemistry have proven successful in achieving the desired level of control for a variety of fundamental studies. This article aims to give an overview of recent progress made in this synthesis technique for the application of controlled catalytic materials in gas-phase catalysis. The focus goes to mono- and bimetallic materials, as well as to recent efforts in enhancing their performance by embedding colloidal templates in porous oxide phases.
  • 3.7K
  • 12 May 2021
Topic Review
Carbon Dots: Synthesis and Properties
Carbon dots (CDs) are zero-dimensional optically active carbon-based nanomaterials with a size of less than 10 nm. The material property of the CD is largely linked to the various bottom-up & top-down synthesis approaches, including surface passivation and functionalization, and the carbon precursors. The CDs can be engineered to enhance the chemical and physical functional properties by doping with heteroatom such as nitrogen, phosphorus, sulfur, fluorine, and boron. Because of its various advantageous properties, CDs are utilized in the field of chemical/biological sensing, bioimaging, and drug delivery. These nanosized CDs can change their light emission properties in response to various external stimuli such as pH, temperature, pressure, and light. The CD’s remarkable stimuli-responsive smart material properties have recently stimulated massive research interest for their exploitation to develop various sensor platforms. 
  • 3.7K
  • 16 Mar 2021
Topic Review
Fundamentals of Oxygen Reduction Reaction
Oxygen reduction reaction (ORR) has been the subject of huge investigation since it is at the heart of various energy conversion and storage systems such as fuel cells, metal-air batteries, and so on. The mechanistic pathway is governed not only by the oxygen adsorption mode, but it also depends on the dissociation barrier of the catalyst surface. 
  • 3.6K
  • 02 Sep 2022
Topic Review
Nanodiamonds Synthesis Techniques
The "state-of-the-art" of the nanodiamonds synthesis techniques is reviewed with emphasis on the more recent one involving pulsed laser ablation. Production of NV centers inside the nanodiamonds and  post-production cleaning processes to remove residual graphite layers are also described.
  • 3.6K
  • 27 Oct 2020
Topic Review
Cationic Surfactants
Cationic surfactants are a class of surfactant molecules that contain a positively charged head group and a long hydrophobic tail. They have a wide range of properties that make them useful in various applications, including solubility in water and organic solvents, high surface activity, emulsification, antimicrobial activity, conditioning properties, and fabric softening. However, some cationic surfactants can be toxic to aquatic life, so they should be used with caution in applications where they may come into contact with the environment. Overall, cationic surfactants are important molecules that play a crucial role in various industrial, personal care, and household applications. Cationic surfactants are a type of surfactant that have a positively charged hydrophilic (water-loving) head and a hydrophobic (water-hating) tail. The positive charge on the head of the surfactant makes it attracted to negatively charged surfaces, such as cell membranes and proteins. Due to their positive charge, cationic surfactants are often used in personal care and household cleaning products, as well as in the textile and paper industries. They are effective in removing dirt, oil, and other contaminants from surfaces, as they can bind to these substances and help to lift them away from the surface. Cationic surfactants can also have antimicrobial properties, as they can disrupt the cell membranes of bacteria and other microorganisms. This makes them useful in disinfectants, as well as in personal care products such as shampoos and body washes.
  • 3.6K
  • 24 Mar 2023
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