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Topic Review
N-Type Layered Oxyselenide Thermoelectric Materials
Bi6Cu2Se4O6is a new type of layered oxyselenide thermoelectric material. The crystal structure of Bi6Cu2Se4O6can be regarded as a 1:2 ratio of BiCuSeO and Bi2O2Se heaping along thec-axis by turns, so there are insulative layersBi2O22+and conductive layersCu2Se22−andSe2−in the structure. The Bi6Cu2Se4O6system not only maintains the low thermal conductivity of BiCuSeO but also can utilize the intrinsic electron carrier concentration of Bi2O2Se, considered to be a promisingn-type oxyselenide thermoelectric material.
  • 1.2K
  • 20 Jul 2021
Topic Review
Bi-Ssubstituted Iron Garnet Multilayer Structures
In this encyclopaedia entry, we are reporting on the unconventional magnetic switching properties of sputtered all-garnet multilayer thin film structures. Within the scope of this study, thin magnetic trilayers were fabricated on both garnet and glass substrates, in which magneto-soft material layers are sandwiched in-between two magneto-hard garnet material layers of identical composition type.
  • 1.2K
  • 30 Oct 2020
Topic Review
Silver Nanoparticles as Anti-Infectious Regents
Silver is easily available and known to have microbicidal effect with wide antibacterial spectrum due to its silver ions mainly; moreover, it does not impose any adverse effects on the human body. Furthermore, the development of multidrug-resistant bacteria, as in the case of antibiotics, is less likely. Recently, silver nanoparticles (Ag NPs) have been synthesized and revealed its anti-viral activity. Because of their characteristics, Ag NPs are useful countermeasures against infectious diseases, which constitute a major issue in the medical field. Therefore, Ag NPs could expect to apply to materials preventing healthcare workers (HCWs), not only patient, from various infection.
  • 1.2K
  • 29 Oct 2020
Topic Review
Short Polymer Fiber-Reinforced Geopolymer Composites
The article describes the state of the art in reinforced geopolymers, taking into consideration various types of polymer fiber reinforcements, such as polypropylene, polyethylene, or polylactic acid. The description is focused on the usage of polymer short fibers and the mechanical properties of the geopolymer composites. However, to show a wider research background, numerous references are discussed concerning the selected studies on reinforcing geopolymer composites with long fibers and fabrics. The research method applied in the article is the critical analysis of literature sources, including a comparison of new material with other materials used in similar applications. The results of the research are discussed in a comparative context and the properties of the composites are juxtaposed with the properties of the standard materials used in the construction industry. Potential applications in the construction industry are presented. Moreover, the contemporary research challenges for geopolymer materials reinforced with fibers are presented.
  • 1.2K
  • 11 Sep 2020
Topic Review
Oligothiophene-Naphthalimide Hybrids Synthetic Approaches
Different variables were tuned in a series of organic semiconductors synthesized in the group of José L. Segura, such as the planarity and the length of their π-conjugated backbones, the topology and energy levels of the frontier molecular orbitals (HOMO and LUMO) and their molecular dipole moments. Studies carried out in the group of Rocío Ponce-Ortiz show that the tuning of these properties can be connected with the microstructure properties observed by atomic force microscopy (AFM) and X-ray diffraction (XRD) in thin films as well as with the performances in organic field-effect transistors (OFETs).
  • 1.2K
  • 11 Jun 2021
Topic Review
Aluminium(I)
In chemistry, aluminium(I) refers to monovalent aluminium (+1 oxidation state) in both ionic and covalent bonds. Along with aluminium(II), it is an extremely unstable form of aluminium. While late Group 3 elements such as thallium and indium prefer the +1 oxidation state, aluminium(I) is rare. Unlike late Group XIII elements, aluminium does not experience the inert pair effect, a phenomenon where valence s electrons are poorly shielded from nuclear charge due to the presence of filled d and f orbitals. As such, aluminium (III) ([math]\ce{ Al^3+ }[/math]) is the much more common oxidation state for aluminium. Aluminium(I) compounds are both prone to disproportionation and difficult to prepare. At standard conditions, they readily oxidize to the aluminium(III) form.
  • 1.2K
  • 14 Nov 2022
Topic Review
Herbicide Resistance Risk and Novel Potential Herbicide Targets
To date, effectively controlling resistant weeds has been a great challenge in modern agricultural production. Developing new modes of action of herbicides would be an efficient, convenient, and . In particular, new modes of herbicide action do not appear to have evolutionary resistance or cross-resistance with existing herbicides. However, a few successful herbicides with new modes of action (MoAs) have been marketed in the past 20 years. Researchers summarized the positive herbicide targets for the herbicides that have been discovered in recent years, such as Solanyl Diphosphate Synthase (SPS), Fatty Acid Thioesterase (FAT), Plastid Peptide Deformylase (PDEF), and Dihydroxy-Acid Dehydratase (DHAD). Some commercial herbicide varieties have been obtained based on novel herbicide targets, such as Homogentisate Solanesyltransferase (HST) and Dihydroorotate Dehydrogenase (DHODH). This provides a new reference and idea for herbicide molecular design in the future. 
  • 1.2K
  • 21 Nov 2022
Topic Review
IBM Microfilm Products
IBM manufactured and sold microfilm products from 1963 till 1969. It is an example of IBM attempting to enter an established market on the basis of a significant technical breakthrough.
  • 1.2K
  • 24 Oct 2022
Topic Review
WO3 and Ionic Liquids -1
Although only recently ILs started to be used to enhance the performances of metal oxides based electrochemical gas sensors (with reference, in particular, to WO3 based sensors), the recognition of their role has been clearly asserted. In fact, not only ILs heavily influence the structure of WO3 nanoparticles when used in the synthetic step (nanoplates, nanorods, nanospheres, etc.), but their residues eventually present on nanoparticles surface can improve the sensed gas adsorption, thus yielding better performances. 
  • 1.2K
  • 29 Oct 2020
Topic Review
Surface Attached Mortar for Recycled Coarse Aggregate
Due to the large amount of old hardened cement mortar attached to the surface of aggregate and the internal micro-cracks formed by the crushing process, the water absorption, apparent density, and crushing index of recycled coarse aggregate are still far behind those of natural coarse aggregate. The results showed that the physical strengthening technique can remove old hardened mortar and micro powder attached to the surface of recycled coarse aggregate by mechanical action, which can effectively improve the quality of recycled coarse aggregate. 
  • 1.2K
  • 04 Jan 2022
Topic Review
Bioremediation of PCBs
PCB, polychorinated biphenyls, are a type of chemical that was widely used in the 1960s and 1970s, and which is a contamination source of soil and water. They are fairly stable and therefore persistent in the environment. Bioremediation of PCBs is the use of microorganisms to degrade PCBs from contaminated sites, which can be either a soil or aqueous environment. It is a process relying on multiple microorganisms' co-metabolism. Anaerobic microorganisms dechlorinate PCBs first, and other microorganisms that are capable of doing BH pathway can break down the dechlorinated PCBs to usable intermediates like acyl-CoA or carbon dioxide. If no BH pathway-caple microorganisms are present, dechlorinated PCBs can be mineralized with help of fungi and plants. However, there are multiple limiting factors for this co-metabolism.
  • 1.2K
  • 29 Nov 2022
Topic Review
Bioshell Calcium Oxide Water
Bioshell calcium oxide (BiSCaO) exhibits broad microbicidal activity for instance. In this study, we examined possible utility of BiSCaO Water for that purpose. The produced BiSCaO Water contained nanoparticles, and was colorless and transparent, with a pH > 12.7. In vitro assays demonstrated that BiSCaO Water eliminated more than 99.9% of influenza A (H1N1) and Feline calicivirus, Escherichia coli within 15 min for instance. BiSCaO Water exhibit excellent disinfection activities against pathogenic bacteria and viruses (including both enveloped and nonenveloped viruses).
  • 1.2K
  • 29 Oct 2020
Topic Review
Lead Halide Perovskites Opto-Electronic Devices
In Lead Halide Perovskites Opto-Electronic Devices, we will discuss the development in the LHP-based functional devices in recent years. After a brief presentation of the LHP's properties, we will focus on the functional devices including lasers, photodetectors, and modulators. Then the fabrication of the LHP-based devices will be presented, which is followed by the summary and outlook.
  • 1.2K
  • 29 Apr 2021
Topic Review
Human Coronaviruses
The ongoing pandemic of the severe acute respiratory syndrome (SARS), caused by the SARS-CoV-2 human coronavirus (HCoV), has brought the international scientific community before a state of emergency that needs to be addressed with intensive research for the discovery of pharmacological agents with antiviral activity. 
  • 1.2K
  • 23 Feb 2021
Topic Review
Thiomersal and Vaccines
Thiomersal (or Thimerosal) is a mercury compound used as a preservative used in some vaccines. Anti-vaccination activists promoting the incorrect claim that vaccination causes autism, have asserted that the mercury in thiomersal is the cause. There is no scientific evidence to support this claim. The idea that thiomersal in vaccines might have detrimental effects originated with anti-vaccination activists and was sustained by them and especially through the action of plaintiffs' lawyers. The potential impact of thiomersal on autism has been investigated extensively. Multiple lines of scientific evidence have shown that thiomersal does not cause autism. For example, the clinical symptoms of mercury poisoning differ significantly from those of autism. In addition, multiple population studies have found no association between thiomersal and autism, and rates of autism have continued to increase despite removal of thiomersal from vaccines. Thus, major scientific and medical bodies such as the Institute of Medicine and World Health Organization (WHO) as well as governmental agencies such as the Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC) reject any role for thiomersal in autism or other neurodevelopmental disorders. In spite of the consensus of the scientific community, some parents and advocacy groups continue to contend that thiomersal is linked to autism and the claim is still stated as if it were fact in anti-vaccination propaganda, notably that of Robert F. Kennedy, Jr., through his group Children's Health Defense. Thiomersal is no longer used in most children's vaccines in the United States, with the exception of some types of flu shots. While exposure to mercury may result in damage to brain, kidneys, and developing fetus, the scientific consensus is that thiomersal has no such effects. This controversy has caused harm due to parents attempting to treat their autistic children with unproven and possibly dangerous treatments, discouraging parents from vaccinating their children due to fears about thiomersal toxicity and diverting resources away from research into more promising areas for the cause of autism. Thousands of lawsuits have been filed in the U.S. to seek damages from alleged toxicity from vaccines, including those purportedly caused by thiomersal. US courts have ruled against multiple representative test cases involving thiomersal. A 2011 journal article described the vaccine-autism connection as "perhaps, the most damaging medical hoax of the last 100 years". Outside of the United States, worries about thiomersal had not gained any significant traction as of 2009.
  • 1.2K
  • 21 Nov 2022
Topic Review
Mathematical models predict corrosion inhibition
The use of corrosion inhibitors is an important method to retard the process of metallic attack by corrosion. The construction of mathematical models from theoretical-computational and experimental data obtained for different molecules is one of the most attractive alternatives in the analysis of corrosion prevention, whose objective is to define those molecular characteristics that are common in high-performance corrosion inhibitors.
  • 1.2K
  • 11 Mar 2021
Topic Review
Tyrocidine
Tyrocidine is a mixture of cyclic decapeptides produced by the bacteria Bacillus brevis found in soil. It can be composed of 4 different amino acid sequences, giving tyrocidine A–D. Tyrocidine is the major constituent of tyrothricin, which also contains gramicidin. Tyrocidine was the first commercially available antibiotic, but has been found to be toxic toward human blood and reproductive cells. The function of tyrocidine within its host B. brevis is thought to be regulation of sporulation. Tyrocidines A, B, and C are cyclic decapeptides. The biosynthesis of tyrocidine involves three enzymes. Parts of its sequence are identical to gramicidin S.
  • 1.2K
  • 15 Nov 2022
Topic Review
Lanthanoid-containing anilato complexes and lattices
Coordination polymers (CPS) and metal organic frameworks (MOFs) with lanthanide compounds (LN) have attracted more and more attention in the past decade, because they may exhibit gas and solvent exchange and adsorption / absorption, and exhibit interesting magnetic and luminescent properties, so they can be used to prepare optical and magnetic sensors for gases.
  • 1.2K
  • 12 Jan 2021
Topic Review
Organochloride
An organochloride, organochlorine compound, chlorocarbon, or chlorinated hydrocarbon is an organic compound containing at least one covalently bonded atom of chlorine. The chloroalkane class (alkanes with one or more hydrogens substituted by chlorine) provides common examples. The wide structural variety and divergent chemical properties of organochlorides lead to a broad range of names, applications, and properties. Organochlorine compounds have wide use in many applications, though some are of profound environmental concern, with TCDD being one of the most notorious.
  • 1.2K
  • 13 Oct 2022
Topic Review
Photonic Sensing Devices
Photonic sensing devices have become increasingly important in various fields such as agriculture, medicine, biochemical sensing, and manufacturing. They are highly sensitive and can classify minor changes in the physical and chemical properties of the ambient medium with high precision. This makes them practical in applications where accurate measurements are critical, such as medical diagnostics and environmental monitoring. 
  • 1.2K
  • 28 Jun 2023
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