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Topic Review
Chemical Composition on Heating Value of Biomass
Biomass has become an increasingly important resource for energy generation. It is well known that the heating value of lignin is significantly higher (23.26–25.58 MJ/kg) than that of polysaccharides (18.6 MJ/kg), while extractives often have higher heating values (HHVs) over 30 MJ/kg, depending on their oxidation levels. Therefore, the proportions of the chemical components in biomass determine its HHV.
  • 3.7K
  • 31 May 2023
Topic Review
Zoroastrianism in India
Zoroastrianism in India has significant history within the country. The initial migration following the Muslim conquest of Persia has been canonized as a religious persecution by invading Muslims. Zoroastrianism meanwhile suffered a decline in Iran after the conquests. Subsequent migrations also took place after the attempts by Safavids to convert their subjects to Shiism. Due to persecution of Zoroastrians in other countries and the liberal atmosphere and patronisation of India, today the largest population of Zoroastrians resides in India, where Zoroastrians have been allowed to play a notable role in the Indian economy, entertainment, the armed forces, and the Indian freedom movement during British Raj. The Zoroastrian groups are regarded as either Parsi or Irani depending on the time of migration to India.
  • 3.7K
  • 09 Nov 2022
Topic Review
Electrodeposition of Common Metals
The electrodeposition process of metals and their alloys is widely used in the automotive, space, electronics, computing, jewelry, and other consumer items industries.
  • 3.7K
  • 15 Dec 2022
Topic Review
Idealization (Science Philosophy)
Idealization is the process by which scientific models assume facts about the phenomenon being modeled that are strictly false but make models easier to understand or solve. That is, it is determined whether the phenomenon approximates an "ideal case," then the model is applied to make a prediction based on that ideal case. If an approximation is accurate, the model will have high predictive accuracy; for example, it is not usually necessary to account for air resistance when determining the acceleration of a falling bowling ball, and doing so would be more complicated. In this case, air resistance is idealized to be zero. Although this is not strictly true, it is a good approximation because its effect is negligible compared to that of gravity. Idealizations may allow predictions to be made when none otherwise could be. For example, the approximation of air resistance as zero was the only option before the formulation of Stokes' law allowed the calculation of drag forces. Many debates surrounding the usefulness of a particular model are about the appropriateness of different idealizations.
  • 3.7K
  • 28 Sep 2022
Topic Review
The Nitrogen Bond
The nitrogen bond in chemical systems occurs when there is evidence of a net attractive interaction between the electrophilic region associated with a covalently or coordinately bound nitrogen atom in a molecular entity and a nucleophile in another, or the same molecular entity. It is the first member of the family of pnictogen bonds formed by the first atom of the pnictogen family, Group 15, of the periodic table, and is an inter- or intra-molecular non-covalent interaction.
  • 3.7K
  • 25 Mar 2022
Topic Review
Radar-Based Drone Detection Technologies
The fast development of unmanned aerial vehicles (UAVs), commonly known as drones, has brought a unique set of opportunities and challenges to both the civilian and military sectors. While drones have proven useful in sectors such as delivery, agriculture, and surveillance, their potential for abuse in illegal airspace invasions, privacy breaches, and security risks has increased the demand for improved detection and classification systems. Principles of radar-based detection: Radar, which stands for “Radio Detection and Ranging”, is generally considered one of the most trustworthy sensing devices that comes to mind when addressing UAV detection since it has traditionally been utilized for aircraft detection in both military and civilian purposes (such as aviation). Radar is an electromagnetic technology that employs radio waves to detect and locate nearby objects. Any radar system works on the basis of echo-based measurements and consists of a radar transmitter that sends out short electromagnetic waves in the radio or microwave band, transmitting and receiving antennas, a radar receiver that receives the reflected signals from the target, and a processor that identifies the objects’ attributes. Therefore, radar can calculate important object characteristics, including distance, velocity, azimuth, and elevation.
  • 3.7K
  • 04 Jan 2024
Topic Review
Multicomponent Bargellini Reaction
The multicomponent reaction between phenol, chloroform and acetone is known as Bargellini reaction. In this  article we collected and discussed all the Bargellini and Bargellini-like reactions carried out over the years. The main goal is that this knowledge-sharing will help chemists to properly use this transformation and imagine novel reactivities based on it.
  • 3.7K
  • 08 Mar 2021
Topic Review
Electrospun Nanofibers: Basic Principles
Electrospun nanofibers had been gaining importance in several areas such as the biomedical, environmental, food, textile, and biotechnology industries, amongst others. The fabrication of three-dimensional membranes through the electrospinning technique confers several characteristics that are important in the above industrial approaches such as high-to-volume radio, high surface area, controllable porosity, thickness, and mechanical properties, also the non-toxicity, biocompatibility, and biodegradability can be conferred to the scaffolds by choosing the adequate polymeric formulation. This entry discusses the characteristics and importance of electrospun nanofibers in industry.
  • 3.7K
  • 13 Aug 2021
Topic Review
Vitamin E
Vitamin E is a common compound used for tocopherols and tocotrienols (α, β, γ, δ); it is the component of many natural products of both plant and animal origin. 
  • 3.7K
  • 12 Jul 2021
Topic Review
Etiopathogenesis of Psoriasis
The underlying basis of psoriasis is skin inflammation (and, in the case of psoriatic arthritis, inflammation of the connective tissue which makes up the joints and the joint ligaments). The characteristic features of skin inflammation include hyperplasia of the epidermis, parakeratosis, and an inflammatory infiltration consisting of dendritic cells, macrophages, T-lymphocytes, and neutrophils. Abnormalities in the skin’s immune response are responsible for the development of the inflammation.
  • 3.7K
  • 09 Feb 2022
Topic Review
Impacts of Agroforestry on Rural Communities
Agroforestry can be used as an alternative way to tackle ecological crisis, while at the same time, sustaining crop production. This system integrates tree growing and crop cultivation and/or animal production on the same land management, based on spatial arrangement or temporal sequence. With such tree integration, agroforestry can preserve natural ecosystems through sustainable land management (including reforestation) and optimal resource utilization. Moreover, agroforestry can potentially mitigate climate change, as several practices within the system are found to improve carbon sequestration and therefore reducing greenhouse gas (GHG) emissions. Moreover, the system can promote biodiversity through the incorporation of different species of plants/crops which may provide homes for various wildlife. Apart from its positive impact on the environment, several studies have also highlighted the socio-economic benefits of agroforestry for rural communities. The implementation of a diverse agroecosystem including trees (timbers, fruits) and livestock might provide alternative incomes for the community promoting economic resilience. Furthermore, the system might improve household food security through diversified food sources. Thus, agroforestry might also become a solution for the existing socio-economic issues.
  • 3.7K
  • 14 Apr 2022
Topic Review
Natural Fiber Composites
Recent advancements in natural fiber composites have minimized the usage of man-made fibers, especially in the field of structural applications such as aircraft stiffeners and rotor blades. However, large variations in the strength and modulus of natural fiber degrade the properties of the composites and lower the safety level of the structures under dynamic load. Without compromising the safety of the composite structure, it is significant to enrich the strength and modulus of natural fiber reinforcement for real-time applications.
  • 3.7K
  • 17 May 2022
Topic Review
Energy Piles
Energy piles are a relatively new technology that have dual function as heat transferring and load bearing. Due to the influence of temperature cycles, additional thermal stress and relative displacement of the pile will be generated; this is different from the load transferring mechanism of the conventional pile. In order to study the thermodynamic characteristics of the energy pipe pile under dual working conditions and temperature cycles, field tests were carried out on the PHC (prestressed high-strength concrete) energy pipe pile without constraining on the top of the piles. Displacement gauges were arranged on the top of the pile, and concrete strain gauges (temperature, strain) were embedded in the pile.
  • 3.7K
  • 31 Jul 2021
Topic Review
Historia Animalium (Gessner)
Historia animalium ("History of the Animals"), published at Zurich in 1551–58 and 1587, is an encyclopedic "inventory of renaissance zoology" by Conrad Gessner (1516–1565). Gessner was a medical doctor and professor at the Carolinum in Zürich, the precursor of the University of Zurich. The Historia animalium is the first modern zoological work that attempts to describe all the animals known, and the first bibliography of natural history writings. The five volumes of natural history of animals cover more than 4500 pages.
  • 3.7K
  • 22 Nov 2022
Topic Review
African Bush Elephant
The African bush elephant (Loxodonta africana), also known as the African savanna elephant, is the largest living terrestrial animal with bulls reaching a shoulder height of up to 3.96 m (13.0 ft). Both sexes have tusks, which erupt when they are 1–3 years old and grow throughout life. It is distributed across 37 African countries and inhabits forests, grasslands and woodlands, wetlands and agricultural land. Since 2004, it has been listed as Vulnerable on the IUCN Red List. It is threatened foremost by habitat destruction, and in parts of its range also by poaching for meat and ivory. It is a social mammal, traveling in herds composed of cows and their offspring. Adult bulls usually live alone or in small bachelor groups. It is a herbivore, feeding on grasses, creepers, herbs, leaves and bark.
  • 3.7K
  • 05 Dec 2022
Topic Review
Critical Heat Flux Amelioration
Critical heat flux (CHF) is the thermal limit of a phase change phenomenon where boiling occurs during heating, which suddenly decreases the efficiency of heat transfer. Ameliorating CHF by altering the boiling surface characteristics can lead to more efficiency, safety, and reliability of the system.
  • 3.7K
  • 11 Aug 2020
Topic Review
Neuron Migration
Radial neuron migration in the developing cerebral cortex is a complex journey, starting in the germinal zones and ending in the cortical plate. In mice, migratory distances can reach several hundreds of microns, or millimeters in humans. Along the migratory path, radially migrating neurons slither through cellularly dense and complex territories before they reach their final destination in the cortical plate.
  • 3.7K
  • 06 Jan 2021
Topic Review
Palm Oil Mill Effluent
Palm oil mill effluent (POME) requires treatment prior to discharge to the environment. Biological processing technology is highly preferable due to its advantages of environmentally friendliness, cost effectiveness, and practicality. These methods utilized various designs and modifications of bioreactors fostering effective fermentation technology in the presence of fungi, bacteria, microalgae, and a consortium of microorganisms.
  • 3.7K
  • 14 Apr 2022
Topic Review
Polarization Holography
Polarization holography has the unique capacity to record and retrieve the amplitude, phase, and polarization of light simultaneously in a polarization-sensitive recording material and has attracted widespread attention. Polarization holography is a noteworthy technology with potential applications in the fields of high-capacity data storage, polarization-controlled optical elements, and other related fields.
  • 3.7K
  • 23 Jan 2021
Topic Review
Yangtze River Valley
The Yangtze River Valley is an important economic region and one of the cradles of human civilization. It is also the site of frequent floods, droughts, and other natural disasters. Conducting Holocene environmental archaeology research in this region is of great importance when studying the evolution of the relationship between humans and the environment and the interactive effects humans had on the environment from 10.0 to 3.0 ka BP, for which no written records exist.
  • 3.7K
  • 29 Apr 2021
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