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Topic Review
Addressing, Assessing and Improving Water Security
Water security is about managing too much, too little and/or too polluted water. Water security is about the increasing importance of sustainable management of water resources, drinking water and human well-being and protection of life and property from water-related disasters. Water security is about the health of ecosystems and economic development.  A groundwork of this broad and multi-faceted concept is presented to facilitate understanding, measuring and improving water security. 
  • 1.8K
  • 25 Jan 2022
Topic Review
Runaway Climate Change
Runaway climate change or runaway global warming is hypothesized to follow a tipping point in the climate system, after accumulated climate change initiates a reinforcing positive feedback. This rapid acceleration in climate change may lead to potentially irreversible damage to the climate system, making timely mitigation efforts unfeasible. This is thought to cause the climate to rapidly change until it reaches a new stable condition. These phrases may be used with reference to concerns about rapid global warming. Some astronomers use the expression runaway greenhouse effect to describe a situation where the climate deviates catastrophically and permanently from the original state—as happened on Venus. Although these terms are rarely used in the peer-reviewed climatological literature, that literature does use the similar phrase "runaway greenhouse effect", which refers specifically to climate changes that cause a planetary body's water to boil off.
  • 1.8K
  • 01 Nov 2022
Topic Review
List of Minerals (Complete)
Mineralogy is an active science in which minerals are discovered or recognised on a regular basis. Use of old mineral names is also discontinued, for example when a name is no longer considered valid. Therefore, a list of recognised mineral species is never complete. Minerals are distinguished by various chemical and physical properties. Differences in chemical composition and crystal structure distinguish the various species. Within a mineral species there may be variation in physical properties or minor amounts of impurities that are recognized by mineralogists or wider society as a mineral variety. The International Mineralogical Association (IMA) is the international group that recognises new minerals and new mineral names. However, minerals discovered before 1959 did not go through the official naming procedure. Some minerals published previously have been either confirmed or discredited since that date. This list contains a mixture of mineral names that have been approved since 1959 and those mineral names believed to still refer to valid mineral species (these are called "grandfathered" species). Presently, each year about 90-110 new mineral species (the sum of all mutations c. 120/year) are officially approved by the Commission on New Minerals, Nomenclature and Classification (CNMNC) of the International Mineralogical Association. The IMA/CNMNC administrates c. 6,500 names, and (As of January 2018), the Handbook of Mineralogy lists 4,507 species. (As of March 2018), the IMA Database of Mineral Properties/ Rruff Project lists 5,312 valid species (IMA/CNMNC) of a total of 5,525 minerals. There are 1,289 Pre-IMA minerals. (As of April 2011), the Webmineral.com website lists 2,722 published and approved (IMA/CNMNC) minerals, 81 discredited minerals (IMA/CNMNC status; Michael Fleischer discredited around thousand species in his lifetime), 2,691 synonyms and 123 "not approved" names. (As of November 2018), the IMA - CNMNC Master List of Minerals lists 5,413 valid minerals, including c. 1,166 pre-IMA minerals (grandfathered), c. 272 approved minerals but without a published description yet and c. 99 questionable minerals. Due to the length of this list, it is divided into alphabetical groups. The minerals are sorted by name.
  • 1.8K
  • 02 Nov 2022
Topic Review
Climate Variability
Climate variability is the term to describe variations in the mean state and other characteristics of climate (such as chances or possibility of extreme weather, etc.) "on all spatial and temporal scales beyond that of individual weather events." Some of the variability does not appear to be caused systematically and occurs at random times. Such variability is called random variability or noise. On the other hand, periodic variability occurs relatively regularly and in distinct modes of variability or climate patterns. Over the years, the definitions of climate variability and the related term climate change have shifted. While the term climate change now implies change that is both long-term and of human causation, in the 1960s the word climate change was used for what we now describe as climate variability, that is, climatic inconsistencies and anomalies.
  • 1.8K
  • 11 Nov 2022
Topic Review
Impact of Tritium on Living Organisms
Tritium is a byproduct of many radiochemical reactions in the nuclear industry, and its effects on aquatic organisms, particularly low-dose effects, deserve special attention. The low-dose effects of tritium on aquatic microbiota have been intensively studied using luminous marine bacteria as model microorganisms. Low-dose physiological activation has been demonstrated and explained by the signaling role of reactive oxygen species through the “bystander effect” in bacterial suspensions. The activation of microbial functions in natural reservoirs by low tritium concentrations can cause unpredictable changes in food chains and imbalances in the natural equilibrium. The incorporation of tritium from the free form into organically bound compounds mainly occurs in the dark and at a temperature of 25 °C. When tritium is ingested by marine animals, up to 56% of tritium is accumulated in the muscle tissue and up to 36% in the liver. About 50% of tritium in the liver is bound in non-exchangeable forms. Human ingestion of water and food products contaminated with background levels of tritium does not significantly contribute to the total dose load on the human body. 
  • 1.8K
  • 22 Apr 2022
Topic Review
Uranium Mineralization of Fossil Wood
Sandstone-hosted uranium deposits commonly contain abundant organic matter, including fossil logs. The precipitation of uranium minerals is often related to reducing environments associated with these organic materials. Below the water table, uranium is likely to be precipitated as uraninite (UO2), but in drier zones a variety of uranium minerals may be found. These minerals may occur as replacements for cellular tissue, or as surface crusts or fracture fillings.
  • 1.8K
  • 28 Oct 2020
Topic Review
Constructed Wetland Components in Wastewater Treatment
An efficient approach to treating anthropogenic discharge (e.g., wastewater, effluents from agriculture and industry, stormwater runoff) is to create a constructed wetland (CW), which simulates natural marshland or swampland. These artificial wetlands employ physical, chemical, and/or biological methods, either consecutively or concurrently, to convert and extract different contaminants from the wastewater, and as such are highly intricate systems. Different system components of CWs, such as the porous bed, plants, and microorganisms, have contribution to the removal of phenols in wastewater treatment. 
  • 1.8K
  • 23 Mar 2022
Topic Review
Precambrian
The Precambrian (or Pre-Cambrian, sometimes abbreviated pЄ, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of the Phanerozoic eon, which is named after Cambria, the Latinised name for Wales, where rocks from this age were first studied. The Precambrian accounts for 88% of the Earth's geologic time. The Precambrian (colored green in the timeline figure) is an informal unit of geologic time, subdivided into three eons (Hadean, Archean, Proterozoic) of the geologic time scale. It spans from the formation of Earth about 4.6 billion years ago (Ga) to the beginning of the Cambrian Period, about 541 million years ago (Ma), when hard-shelled creatures first appeared in abundance.
  • 1.8K
  • 15 Nov 2022
Topic Review
Application of the IoT in Disaster Risk Management
Taiwan is in a hazard-exposed area where people often suffer through typhoons, earthquakes, and landslides, and must face the challenges of environmental and climate changes in ongoing and future developments. Taiwan has implemented an integrated and interdisciplinary project, which is titled Civil IoT Taiwan, for better disaster risk management and risk communication with all stakeholders by cooperating closely with authorities, scientists, and industry. 
  • 1.8K
  • 30 Dec 2021
Topic Review
Techno-Economic and Life Cycle Cost Analysis
The techno-economic analysis (TEA) and the life cycle cost analysis (LCCA) are the most widely used approaches for modeling and calculating processes’ economic impacts. A simulation-based TEA is a cost-benefit analysis that simultaneously considers technical and economic factors. In addition, the method facilitates the development of the entire project and provides a systematic approach for examining the interrelationships between economic and technological aspects. When it comes to economic studies, it is intimately bonded with uncertainty. There are numerous uncertainty sources, classified in various ways. The uncertainty reflects “an inability to determine the precise value of one or more parameters affecting a system.” The variability refers to the different values a given parameter may take. This implies that a probability density function (PDF), for instance, can be employed to estimate and quantify the variability of a given parameter. The bias refers to “assumptions that skew an analysis in a certain direction while ignoring other legitimate alternatives, factors, or data.” 
  • 1.8K
  • 21 Oct 2022
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