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Topic Review
H2 in CO Oxidation over Ceria Catalysts
The preferential CO oxidation (so-called CO-PROX) is the selective CO oxidation amid H2-rich atmospheres, a process where ceria-based materials are consolidated catalysts. This article aims to disentangle the potential CO–H2 synergism under CO-PROX conditions on the low-index ceria surfaces (111), (110) and (100). Polycrystalline ceria, nanorods and ceria nanocubes were prepared to assess the physicochemical features of the targeted surfaces. Diffuse reflectance infrared Fourier-transformed spectroscopy (DRIFTS) shows that ceria surfaces are strongly carbonated even at room temperature by the effect of CO, with their depletion related to the CO oxidation onset. Conversely, formate species formed upon OH + CO interaction appear at temperatures around 60 °C and remain adsorbed regardless the reaction degree, indicating that these species do not take part in the CO oxidation. Density functional theory calculations (DFT) reveal that ceria facets exhibit high OH coverages all along the CO-PROX reaction, whilst CO is only chemisorbed on the (110) termination. 
  • 344
  • 13 Jan 2022
Topic Review
H2 Antagonist
H2 antagonists, sometimes referred to as H2RAs and also called H2 blockers, are a class of medications that block the action of histamine at the histamine H2 receptors of the parietal cells in the stomach. This decreases the production of stomach acid. H2 antagonists can be used in the treatment of dyspepsia, peptic ulcers and gastroesophageal reflux disease. They have been surpassed by proton pump inhibitors (PPIs); the PPI omeprazole was found to be more effective at both healing and alleviating symptoms of ulcers and reflux oesophagitis than the H2 blockers ranitidine and cimetidine. H2 antagonists are a type of antihistamine, although in common use the term "antihistamine" is often reserved for H1 antagonists, which relieve allergic reactions. Like the H1 antagonists, some H2 antagonists function as inverse agonists rather than receptor antagonists, due to the constitutive activity of these receptors. The prototypical H2 antagonist, called cimetidine, was developed by Sir James Black at Smith, Kline & French – now GlaxoSmithKline – in the mid-to-late 1960s. It was first marketed in 1976 and sold under the trade name Tagamet, which became the first blockbuster drug. The use of quantitative structure-activity relationships (QSAR) led to the development of other agents – starting with ranitidine, first sold as Zantac, which has fewer adverse effects and drug interactions and is more potent. H2 blockers, which all end in "-tidine," are not the same as H1 receptor antagonists, which relieve allergy symptoms.
  • 439
  • 31 Oct 2022
Topic Review
H2S Sensors
Hydrogen sulfide (H2S) is an essential signaling gas within the cell, and its endogenous levels are correlated with various health diseases such as Alzheimer’s disease, diabetes, Down’s syndrome, and cardiovascular disease. Because it plays such diverse biological functions, being able to detect H2S quickly and accurately in vivo is an area of heightened scientific interest.
  • 419
  • 06 May 2023
Topic Review
Gum Tragacanth
Gum tragacanth (GT) is recently showing great promise as a therapeutic substance in tissue engineering and regenerative medicine.
  • 1.5K
  • 29 Jun 2021
Topic Review
Growth and Characterizations of SILAR-Deposited Thin Films
The prepared thin films could be used in lasers, cathodic ray tubes, solar cells, infrared windows, ultraviolet light emitting diodes, sensors, supercapacitors, biologic applications, and optoelectronic applications. The properties of these thin films strongly depend on the deposition techniques. Many investigations into the production of various types of thin films (by using the successive ionic layer adsorption and reaction (SILAR) method) were conducted. This method attracts interest as it possesses many advantages when compared to other deposition methods. For example, large area depositions could be carried out in any substrates at lower temperatures via inexpensive instruments; moreover, a vacuum chamber is not required, it has an excellent growth rate, and the unique film properties could be controlled.
  • 770
  • 26 Aug 2022
Topic Review
Ground Deicing of Aircraft
Ground deicing of aircraft is commonly performed in both commercial and general aviation. The fluids used in this operation are called deicing or anti-icing fluids. The initials ADF (Aircraft Deicing Fluid), ADAF (Aircraft Deicer and Anti-icer Fluid) or AAF (Aircraft Anti-icing Fluid) are commonly used.
  • 715
  • 23 Nov 2022
Biography
Greg Winter
Sir Gregory Paul Winter CBE FRS FMedSci (born 14 April 1951)[1][2] is a Nobel Prize-winning British biochemist best known for his work on the therapeutic use of monoclonal antibodies. His research career has been based almost entirely at the MRC Laboratory of Molecular Biology and the MRC Centre for Protein Engineering, in Cambridge, England. He is credited with invented techniques to both human
  • 1.5K
  • 16 Nov 2022
Topic Review
Green Tea Catechins
Green tea and green tea catechins have been shown to be strongly inhibitory to cancer formation in rodents. They are believed to do this by altering cells after they have been initiated on the path toward cancer. Green tea and green tea catechin prevention of cancer in humans has been hard to detect. We discuss that the reason for this difference is likely to be the digestive tract microbiome. If green tea catechins are to be continue to be tested for cancer prevention properties in humans it will be necessary to take into account variable digestive tract microbiome metabolism in people so the dose can be optimized for each person thus avoiding toxicity. 
  • 721
  • 03 Nov 2020
Topic Review
Green Tea
Green tea is a type of tea that is made from Camellia sinensis leaves that have not undergone the same withering and oxidation process used to make oolong teas and black teas. Green tea originated in China , but its production and manufacture has spread to many other countries in Asia. Several varieties of green tea exist, which differ substantially based on the variety of C. sinensis used, growing conditions, horticultural methods, production processing, and time of harvest. Although there has been considerable research on the possible health effects of consuming green tea regularly, there is little evidence that drinking green tea has any effects on health.
  • 2.7K
  • 08 Nov 2022
Topic Review
Green Synthetic Approach
Green synthetic protocol refers to the development of processes for the sustainable production of chemicals and materials. For the synthesis of various biologically active compounds, energy-efficient and environmentally benign processes are applied, such as microwave irradiation technology, ultrasound-mediated synthesis, photo-catalysis (ultraviolet, visible and infrared irradiation), molecular sieving, grinding and milling techniques, etc. 
  • 1.6K
  • 01 Jul 2021
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