Chemical Element
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2021 ◽  
pp. 1-9
Author(s):  
Peter Felfer ◽  
Benedict Ott ◽  
Mehrpad Monajem ◽  
Valentin Dalbauer ◽  
Martina Heller ◽  
...  

Atom probe tomography (APT) is a single-ion sensitive time-of-flight mass spectrometry method with near-atomic spatial resolution. In principle, it can be used to detect any chemical element, but so far hydrogen in the form of protium (1H) had to be largely excluded. This is owing to the residual H emitted from the stainless-steel chambers and in-vacuum parts commonly used in atom probe instrumentation. This residual H is then picked up in the APT experiment. In this paper, we show that by replacing the stainless-steel chamber and in-vacuum parts with titanium parts, this residual H can largely be removed, thus enabling the direct imaging of H using APT. We show that besides the drastic reduction of H, also other contaminants such as O, OH, and H2O are reduced by employing this instrument. In the current set-up, the instrument is equipped with high-voltage pulsing limiting the application to conductive materials.


2021 ◽  
Vol 6 (4) ◽  
pp. 9-13
Author(s):  
Svetlana I. Alekseenko ◽  
Vladimir V. Dvoryanchikov ◽  
Anatolii V. Skalny ◽  
Igor A. Anikin ◽  
Vadim S. Isachenko ◽  
...  

Objectives to evaluate the association between essential chemical element levels in whole blood and in pathologic mucosa and chronic rhinosinusitis severity in children. Material and methods. A total of 154 children aged from 6 to 17 years were examined. Among them, 88 children had chronic rhinosinusitis (CRS) and underwent functional endoscopic sinus surgery (FESS). The 66 healthy children were included in the control group. Life quality was assessed using SNOT-20 (Sino-Nasal Outcome Test-20). Endoscopic and computer tomography findings were evaluated using Lund Kennedy and Lund Mackay scales, respectively. The assessment of essential element levels in whole blood samples was performed using inductively-coupled plasma mass-spectrometry. Results. The obtained data demonstrate that total SNOT-20 scores in CRS patients were 68% higher than in controls. At the same time, whole blood calcium, selenium, zinc, and magnesium levels were 6%, 28%, 20%, and 3% lower than the respective control values. The analysis of pathologic mucosa demonstrated that the chemical element contents were reducing in the following order: Ca Mg = Fe Zn Cu Mn Se. However, only whole blood selenium level correlated significantly with its tissue level. In multiple regression models, the whole blood Se level was inversely associated with SNOT-20 and Lund Mackay total scores. Conclusion. Therefore, the obtained data allow to propose the potential role of altered calcium, magnesium, zinc and selenium metabolism in CRS progression.


2021 ◽  
Vol 12 (6) ◽  
pp. 8561-8572

Fluorine is a chemical element belonging to the group of halogens. Due to its many properties, it has been used in various fields of medicine, mainly in dentistry, pharmacology, oncology, and radiology. It is an element that occurs naturally in the environment with a very high chemical activity. In addition, it has a high affinity for calcium or magnesium [1], which may have a large impact on the body's functioning when a higher dose of fluoride is taken. Moreover, fluorine is an element that has toxic effects, not only on living organisms but also on the environment. Fluoride-based preparations are widely used in several areas of medicine. This paper presents the use of fluoride in its various branches of medicine.


Optica ◽  
2021 ◽  
Author(s):  
Yishay Klein ◽  
Or Sefi ◽  
Hila Schwartz ◽  
Sharon Shwartz

2021 ◽  
Vol 24 (4) ◽  
pp. 26-31
Author(s):  
Omar A. Thuhaib ◽  
◽  
Hassan Hashim ◽  

In this work, we analyze the effects of S doping on the structural and optical characteristics of pure cadmium oxide (CdO) filmsat varying concentrations of CdO1−x:Sx(X=0.2, 0.4, and 0.6), Sulfur is a chemical element with the atomic number 16 and the symbol S. The films were created using a laser-induced plasma (LIP) with a wavelength of 1064 nm and a duration of 9 ns at a pressure of 2.5×10−2mbar.X-ray diffraction studies revealed that all of the produced films are polycrystalline. The topography of the film's surface was evaluated using AFM, and the findings revealed that as the amount of doping increases, so does the grain size, along with an increase in the average roughness. The absorbance spectrum of the wavelength range (350-1100) nm was used to investigate the optical characteristics of all films. This rise might be the so-called Borsstein-Moss displacement has been viewed as a result of this. because the lowest layers of the conduction beams are densely packed with Because electrons require more energy to move, it seems as though the energy disparity widens.


2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Satrya Mahardhika ◽  
Frans Santoso ◽  
Nashiruddin Alfath

The purpose of this research is to learn about how IP character can help students remembering their lesson. In this case we apply the research to a subject that majority students having difficulty to learn, it is chemistry. Some students say that chemistry is the hardest subject for them. Some say that the hardest part is to remember codes and elements on chemistry. Even they said it is the most boring subject, and usually they get a bad mark for it. Based on our survey, we find out that most of students having difficulties to study the subject using traditional method. They prefer to learn using graphics, because it is easier to remember the codes. For this case, we create a set of play card that can help students remembering the chemicals codes. Each card has a unique IP Character that resembles chemical element. Writers also add an element, which could make the chemistry lesson easier to understand, that is game. A game rule will be applied on the card game, and it will help student learned chemistry. And to make it more attractive and fun, we also try to put some technology to the game. Using a technology called Augment Reality, we try to engage students more. 


2021 ◽  
Vol 7 (3) ◽  
pp. 99-102
Author(s):  
Kajol M Talreja

Nuclear medicine is the discipline of medicine that deals with the use of radionuclides in research, diagnosis, and treatment. It works on molecular & functional level and uses radiopharmaceuticals in its procedure helping in detection of lesions before morphologic change is evident. Radiopharmaceuticals also known as Radionuclides/ Radioisotopes are unstable atoms of a chemical element, actively emit radiation. These emitted radiations are absorbed by photomultiplier tube and reconstructed by a computer system followed by display of an image. The rationale of writing this article is to understand about Nuclear Medicine and its applications in oral diseases.


Author(s):  
Fithriyyah Karimah ◽  
Tico G Samosir ◽  
Fuaddinda P Salsabila

Hydrogen or sometimes called water, is a chemical element on the periodic table that has the symbol H and atomic number 1. At standard temperatures and pressures, hydrogen is colorless, odorless, non-metallic, singlevalent, and a highly flammable diatomic gas. With an atomic mass of 1.00794 amu, hydrogen is the lightest element in the world. It is also the most abundant element, accounting for roughly 75% of the total elemental mass of the universe. Most stars are formed by hydrogen in the plasma state. Hydrogen compounds are relatively rare and rarely found naturally on Earth, and are usually produced industrially from various hydrocarbons such as methane. Hydrogen can also be produced from water through electrolysis, but this process is more expensive commercially than producing hydrogen from natural gas. With the aim to prove the explosion that occurred and the reaction that occurred during the experimental process of an exothermic or endoderm reaction explosion


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jingzhen Du ◽  
Iskander Douair ◽  
Erli Lu ◽  
John A. Seed ◽  
Floriana Tuna ◽  
...  

AbstractDisproportionation, where a chemical element converts its oxidation state to two different ones, one higher and one lower, underpins the fundamental chemistry of metal ions. The overwhelming majority of uranium disproportionations involve uranium(III) and (V), with a singular example of uranium(IV) to uranium(V/III) disproportionation known, involving a nitride to imido/triflate transformation. Here, we report a conceptually opposite disproportionation of uranium(IV)-imido complexes to uranium(V)-nitride/uranium(III)-amide mixtures. This is facilitated by benzene, but not toluene, since benzene engages in a redox reaction with the uranium(III)-amide product to give uranium(IV)-amide and reduced arene. These disproportionations occur with potassium, rubidium, and cesium counter cations, but not lithium or sodium, reflecting the stability of the corresponding alkali metal-arene by-products. This reveals an exceptional level of ligand- and solvent-control over a key thermodynamic property of uranium, and is complementary to isolobal uranium(V)-oxo disproportionations, suggesting a potentially wider prevalence possibly with broad implications for the chemistry of uranium.


2021 ◽  
Vol 6 (1) ◽  
pp. 40-45
Author(s):  
Edy Agustian Yazid ◽  
Abdul Wafi ◽  
Arina Saraswati

Iron is a chemical element that is found in almost every place on earth, including in well water or groundwater. Iron can be suspended in water with organic substances or inorganic solids in the form of ferrous cations (Fe2+) and ferries (Fe3+). The presence of iron that exceeds the threshold can cause detrimental effects such as corrosion of the piping, the color of the water turns brown, smells bad, and can cause health problems. The iron content in groundwater can be reduced so that it can be used as water that is fit for consumption or use in everyday life. This study aims to determine several types of techniques used to reduce iron in groundwater or well water through literature studies. Techniques covered include filtration, aeration, adsorption, coagulation, electrocoagulation, and cascade aerators. The results showed that the greatest reduction in efficiency was found in the combination type of adsorption technique and filtration technique by more than 99.1%, then followed by the electrocoagulation technique of  99.74%. From all the techniques studied in this study, it can be concluded that all techniques can reduce iron levels in which the combination of adsorption and filtration techniques is the most effective.Keywords: Technique, reduction, iron content, groundwater


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