Relevant bibliographies by topics / Atomic expension

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Book chapters
  4. Conference papers
  5. Reports

Academic literature on the topic 'Atomic expension'

Author: Grafiati
Published: 4 June 2021
Last updated: 25 May 2024

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Journal articles on the topic "Atomic expension"

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Gao, Peng, Zonghang Liu, Jie Zhang, Jia-Ao Wang, and Graeme Henkelman. "A Fast, Low-Cost and Simple Method for Predicting Atomic/Inter-Atomic Properties by Combining a Low Dimensional Deep Learning Model with a Fragment Based Graph Convolutional Network." Crystals 12, no. 12 (2022): 1740. http://dx.doi.org/10.3390/cryst12121740.

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Calculations with high accuracy for atomic and inter-atomic properties, such as nuclear magnetic resonance (NMR) spectroscopy and bond dissociation energies (BDEs) are valuable for pharmaceutical molecule structural analysis, drug exploration, and screening. It is important that these calculations should include relativistic effects, which are computationally expensive to treat. Non-relativistic calculations are less expensive but their results are less accurate. In this study, we present a computational framework for predicting atomic and inter-atomic properties by using machine-learning in a
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López-García, Ignacio, Juan José Marín-Hernández, and Manuel Hernández-Córdoba. "Microcrystalline cellulose for the dispersive solid-phase microextraction and sensitive determination of chromium in water using electrothermal atomic absorption spectrometry." Journal of Analytical Atomic Spectrometry 33, no. 9 (2018): 1529–35. http://dx.doi.org/10.1039/c8ja00215k.

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Offem, J. O., and O. S. O. Edet. "Spectrophotometric determination of manganese based on thermally produced manganese (VI) compounds in plant ash." Journal of Agricultural Science 112, no. 3 (1989): 427–31. http://dx.doi.org/10.1017/s0021859600085890.

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Atomic Absorption Spectroscopy (AAS) is the usual method for the direct determination of small amounts of manganese in plant materials (Christian & Feldman 1970; Heanes, 1981) and other substances (Carnrick, Slavin & Manning, 1981). However, it uses the highly sophisticated and expensive Atomic Absorption Spectrometer, which requires a reasonable degree of technician expertise, and is therefore not suitable for routine chemical analyses in Third World countries.
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Chen, Nan, Yong Sheng Shi, Meng Zhao, and Meng Ru Xuan. "Comparison of Antimony Determination Methods in Drinking Water." Advanced Materials Research 706-708 (June 2013): 478–82. http://dx.doi.org/10.4028/www.scientific.net/amr.706-708.478.

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Antimony distributes widely in the environment. And antimony pollution in the water environment is becoming serious. How to detect the content of the antimony correctly and effectively is very important. Graphite furnace atomic absorption method is simple, but low sensitivity; hydride generation atomic fluorescence spectrometry, low cost, good reproducibility, but is harmful to the introduction of substances; inductively coupled plasma mass spectrometry for simultaneous multi-element analysis, high sensitivity, but the operation is cumbersome; inductively coupled plasma spectrometry has low de
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He, Xin, Tao Jiang, Zhen-Fu Zhang, and Jun-Bo Yang. "Bound-state characteristic temperature method and its applications." Acta Physica Sinica 71, no. 8 (2022): 085201. http://dx.doi.org/10.7498/aps.71.20212115.

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As the speed of a hypersonic vehicle increases, atomic emission lines in the shock-layer will be a main source of radiative heating. Therefore, it is very important to study the atomic excitation in the air plasma in the shock layer. For a thermal nonequilibrium air plasma, the equilibrium statistical theory is not applicable. Although full models (such as the collisional-radiative model) can be used to solve nonequilibrium problems with high accuracy, they are too expensive computationally and difficult to apply to engineering. In this work, we investigate the atomic excitation in air plasmas
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Belmonte, Maria Teresa, Pratysuh R. Sen Sarma, and Santiago Mar. "Accurate new atomic data for Galactic Surveys." Proceedings of the International Astronomical Union 18, S371 (2022): 111–22. http://dx.doi.org/10.1017/s1743921323000273.

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AbstractFor the last 20 years, Galactic Surveys have been revolutionizing our vision of the universe and broadening our understanding of the vastness of space that surrounds us. Galactic Surveys such as APOGEE, Gaia-ESO, GALAH, WEAVE and the currently-under-development 4MOST are teaching us a great deal about the chemical composition of stellar atmospheres, the formation and evolution of galaxies and how elements are synthesised in the universe. However, many questions remain unanswered and the current focus of ongoing and future surveys. Answering each of these questions requires the collecti
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Scott, H. A., J. A. Harte, M. E. Foord, and D. T. Woods. "Using tabulated NLTE data for Hohlraum simulations." Physics of Plasmas 29, no. 8 (2022): 082703. http://dx.doi.org/10.1063/5.0102624.

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Non-local thermodyamic equilibrium (NLTE) atomic kinetics is necessary in inertial confinement fusion Hohlraum simulations for adequately modeling high-Z walls and dopants but is computationally very expensive. We present here an approach for tabulating NLTE material data in an economical manner. Material properties for an arbitrary radiation field are provided through tabulated data for a limited set of radiation fields plus derivatives with respect to components of those radiation fields. We have implemented this method in a radiation-hydrodynamics code and compare Hohlraum simulations done
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G. Caballero, Pujante, Sourmail, et al. "Advanced Heat Treatments and Complex Ferritic Structures for Bearing Steels." Metals 9, no. 11 (2019): 1137. http://dx.doi.org/10.3390/met9111137.

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Nanostructured bainitic steels exhibit an optimum strength/toughness combination as a consequence of their extremely fine structure. They have also demonstrated potential for wear-resistance applications. The aim of this work was to develop bearing steels by the multi-scale control of complex ferritic structures, designed using atomic transformation theory and processed by novel heat treatments. Based on the results, the new ball bearings outperformed conventional grades, approaching more expensive material options.
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Chi, Zhijun, Yingchao Du, Lixin Yan, et al. "Experimental feasibility of dual-energy computed tomography based on the Thomson scattering X-ray source." Journal of Synchrotron Radiation 25, no. 6 (2018): 1797–802. http://dx.doi.org/10.1107/s1600577518012663.

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Unlike large-scale and expensive synchrotron radiation facilities, the Thomson scattering X-ray source can provide quasi-monochromatic, energy-tunable and high-brightness X-ray pulses with a small footprint and moderate cost, making it an excellent candidate for dual-energy and multi-energy imaging at laboratories and hospitals. Here, the first feasibility study on dual-energy computed tomography (CT) based on this type of light source is reported, and the effective atomic number and electron-density distribution of a standard phantom consisting of polytetrafluoroethylene, water and aluminium
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Karimah, Fithriyyah, Tico G. Samosir, and Fuaddinda P. Salsabila. "Identification of Explosion from Hydrogen Gas." Indonesian Journal of Chemical Science and Technology (IJCST) 4, no. 2 (2021): 70. http://dx.doi.org/10.24114/ijcst.v4i2.27599.

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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
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Dissertations / Theses on the topic "Atomic expension"

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Julien, Grégory. "Filtrage Stochastique et amélioration des performances des systèmes de positionnement d’engins sous-marins en milieu bruyant." Thesis, Toulon, 2012. http://www.theses.fr/2012TOUL0018/document.

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Le positionnement d'un engin sous-marin s'appuie sur des systèmes dits "acoustiques". Ces derniers renseignent la position relative de l'engin immergé par rapport au navire support. Les performances de ces systèmes sont définies en termes de limite de portée et de précision. Le principe de ces systèmes repose sur les notions de distance-métrie et de goniométrie, qui s'appuient toutes deux sur l'estimation du temps de propagation et donc de la date d'arrivée du signal utile. Cela est classiquement réalisé par une opération de Compression d'Impulsion. Cette technique qui est largement utilisée d
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Julien, Grégory. "Filtrage Stochastique et amélioration des performances des systèmes de positionnement d’engins sous-marins en milieu bruyant." Electronic Thesis or Diss., Toulon, 2012. http://www.theses.fr/2012TOUL0018.

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Le positionnement d'un engin sous-marin s'appuie sur des systèmes dits "acoustiques". Ces derniers renseignent la position relative de l'engin immergé par rapport au navire support. Les performances de ces systèmes sont définies en termes de limite de portée et de précision. Le principe de ces systèmes repose sur les notions de distance-métrie et de goniométrie, qui s'appuient toutes deux sur l'estimation du temps de propagation et donc de la date d'arrivée du signal utile. Cela est classiquement réalisé par une opération de Compression d'Impulsion. Cette technique qui est largement utilisée d
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Book chapters on the topic "Atomic expension"

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Jeffrey, George A. "Accurate crystal structure analysis by neutron diffraction." In Accurate Molecular Structures. Oxford University PressOxford, 1992. http://dx.doi.org/10.1093/oso/9780198555568.003.0011.

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Abstract Single-crystal neutron diffraction analysis is a long-established method of structure determination which is well documented in textbooks (Willis 1970; Brown and Forsyth 1973; Bacon 1975). Because a neutron-diffraction crystal structure analysis is a relatively expensive and time-consuming experiment, the method serves to complement the deficiencies of X-ray crystal structure analysis. The neutron scattering cross-sections of the atoms vary over a narrow range compared with the X-ray scattering factors, which increase with atomic numbers. Therefore, neutron diffraction is more effective for determining the atomic parameters of light atoms in molecules containing heavy atoms. This is particularly important in the study of hydrogen bonding, both in small molecules and in large biological macromolecules. It is also useful for distinguishing between atoms which are adjacent in the periodic table, where there is only a small proportional difference in the X-ray scattering factors.
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Bulatov, Vasily, and Wei Cai. "Fundamentals of Atomistic Simulations." In Computer Simulations of Dislocations. Oxford University Press, 2006. http://dx.doi.org/10.1093/oso/9780198526148.003.0006.

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Fundamentally, materials derive their properties from the interaction between their constituent atoms. These basic interactions make the atoms assemble in a particular crystalline structure. The same interactions also define how the atoms prefer to arrange themselves in the dislocation core. Therefore, to understand the behavior of dislocations, it is necessary and sufficient to study the collective behavior of atoms in crystals populated by dislocations. This chapter introduces the basic methodology of atomistic simulations that will be applied to the studies of dislocations in the following chapters. Section 1 discusses the nature of interatomic interactions and introduces empirical models that describe these interactions with various degrees of accuracy. Section 2 introduces the significance of the Boltzmann distribution that describes statistical properties of a collection of interacting atoms in thermal equilibrium. This section sets the stage for a subsequent discussion of basic computational methods to be used throughout this book. Section 3 covers the methods for energy minimization. Sections 4 and 5 give a concise introduction to Monte Carlo and molecular dynamics methods. When put close together, atoms interact by exerting forces on each other. Depending on the atomic species, some interatomic interactions are relatively easy to describe, while others can be very complicated. This variability stems from the quantum mechanical motion and interaction of electrons [15, 16]. Henceforth, rigorous treatment of interatomic interactions should be based on a solution of Schrödinger’s equation for interacting electrons, which is usually referred to as the first principles or ab initio theory. Numerical calculations based on first principles are computationally very expensive and can only deal with a relatively small number of atoms. In the context of dislocation modelling, relevant behaviors often involve many thousands of atoms and can only be approached using much less sophisticated but more computationally efficient models. Even though we do not use it in this book, it is useful to bear in mind that the first principles theory provides a useful starting point for constructing approximate but efficient models that are needed to study large-scale problems involving many atoms.
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Bowyer, A. A., and E. J. New. "Fluorescent Platforms for Environmental Sensing." In Fluorescent Chemosensors. The Royal Society of Chemistry, 2023. http://dx.doi.org/10.1039/9781839167324-00378.

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Fluorescent sensors have proved to be useful for environmental monitoring of chemical pollutants and other substances that can cause harm to society and the natural world. Industrial advances since the 19th century have led to a significant increase in polluting substances in the air, water and land. Currently, the most common methods for detecting environmental pollutants include inductively coupled plasma–mass spectrometry (ICP–MS), gas chromatography–mass spectrometry (GC–MS) and atomic absorption spectroscopy (AAS). Although sensitive, these techniques involve the use of large and expensive instruments operated by specially trained personnel, limiting their availability in places other than major cities. Fluorescent sensing platforms provide an attractive alternative to these techniques, as high sensitivity can be achieved while using much cheaper and smaller instrumentation, such as benchtop spectrometers, or even portable devices. In this chapter, we present highlights from the vast array of fluorescent platforms developed for environmental sensing, with a particular focus on examples that have been successfully applied to studies in the field.
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Atkins, Peter. "The Death of Metal: Corrosion." In Reactions. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199695126.003.0012.

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As in life, so in redox reactions: some are good and some are bad. Corrosion is one of the evil among redox reactions. It is the unwanted oxidation of a metal that cuts short the lifetimes of steel products such as bridges and vehicles. Replacing corroded metal parts costs industry and society a huge amount each year. Understanding it helps us to find ways to prevent it. Not all corrosion, however, is unwanted: the green patina of copper roofs is often sought and can be beautiful; the induced oxidation of aluminium in the presence of dyes can also be intentional and can bring graceful colour to a building. I shall focus on the corrosion of iron, Fe (from the Latin ferrum), its rusting, as it is so common a way of death for our everyday artefacts. Iron rusts when it is exposed to damp air, with both oxygen and water present. In the process the Fe atoms of the metal are oxidized—lose some electrons—and become Fe3+ ions. These ions pick up some oxide ions, O2–, and are deposited as the red–brown oxide, Fe2O3. The corrosion of iron is very much like its reversion to the ore, which is also typically Fe2O3, from which, with so great an effort and all the expensive and energy-intensive, environmentally invasive fury of a blast furnace, it was originally obtained (Reaction 4). In the process of forming Fe3+, the oxygen of the air, the oxidizing agent, is converted to water. The hydrogen atoms needed for the formation of H2O molecules from O2 molecules are scavenged from the surrounding solution, especially if it is acidic and rich in hydrogen ions. I shall now show you the reaction in more detail and try to lead you into appreciating visually what is going on inside a small droplet of water on the surface of a sheet of rusting iron. Although rusting is rarely thought beautiful, there is a beauty and subtlety in the choreography of the atomic events that underlie its formation. As usual, you should imagine shrinking to the size of a molecule, plunging below the droplet’s surface, and descending diver-like through the densely agitating, bustling, tumbling water molecules.
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Dyall, Kenneth G., and Knut Faegri. "Spin Separation and the Modified Dirac Equation." In Introduction to Relativistic Quantum Chemistry. Oxford University Press, 2007. http://dx.doi.org/10.1093/oso/9780195140866.003.0022.

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In the preceding chapters, the theory for calculations based on the Dirac equation has been laid out in some detail. The discussion of the methods included a comparison with equivalent nonrelativistic methods, from which it is apparent that four-component calculations will be considerably more expensive than the corresponding nonrelativistic calculations—perhaps two orders of magnitude more expensive. For this reason, there have been many methods developed that make approximations to the Dirac equation, and it is to these that we turn in this part of the book. There are two elements of the Dirac equation that contribute to the large amount of work: the presence of the small component of the wave function and the spin dependence of the Hamiltonian. The small component is primarily responsible for the large number of two-electron integrals which, as will be seen later, contain all the lowest-order relativistic corrections to the electron–electron interaction. The spin dependence is incorporated through the kinetic energy operator and the correction to the electronic Coulomb interaction, and also through the coupling of the spin and orbital angular momenta in the atomic 2-spinors, which form a natural basis set for the solution of the Dirac equation. Spin separation has obvious advantages from a computational perspective. As we will show for several spin-free approaches below, a spin-free Hamiltonian is generally real, and therefore real spin–orbitals may be employed for the large and small components. The spin can then be factorized out and spin-restricted Hartree–Fock methods used to generate the one-electron functions. In the post-SCF stage, where the no-pair approximation is invoked, the transformation of the integrals from the atomic to the molecular basis produces a set of real molecular integrals that are indistinguishable from a set of nonrelativistic MO integrals, and therefore all the nonrelativistic correlation methods may be employed without modification to obtain relativistic spin-free correlated wave functions. In most cases, spin–free relativistic effects dominate the relativistic corrections to electronic structure. We will show later that in a perturbation expansion based on the nonrelativistic wave function, the spin-free effects for a closed-shell system enter in first order, whereas the spin-dependent effects make their first contribution in second order.
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Primrose, William U. "Sample preparation." In NMR of Macromolecules. Oxford University PressOxford, 1993. http://dx.doi.org/10.1093/oso/9780199632251.003.0002.

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Abstract Over the last few years, there have been rapid and sustained advances in the hardware and software associated with the NMR analysis of biological macromolecules. Larger magnets, faster computers, and new and improved pulse sequences have been combined with isotopic labelling to make NMR the unrivalled method for answering biological questions at the atomic level in the solution state. These dramatic advances have perhaps tended to obscure the importance of correct preparation of the sample, which tends to be a rather poorly documented subject. The purpose of this chapter is to aid you in the correct choice of conditions for preparation of your vital and hard-won sample. This will then allow you to obtain the maximum benefit from the sophisticated spectroscopic methods described in other chapters in this book. The importance of correct handling of the sample cannot be over-emphasized, as no amount of expensive spectrometer and computer equipment can compensate for an intrinsically poor sample. A Formula One racing car will not break any lap records running on two-stroke fuel !
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Freedman, Lawrence. "Beyond Massive Retaliation." In Kennedy’s Wars. Oxford University PressNew York, NY, 2000. http://dx.doi.org/10.1093/oso/9780195134537.003.0003.

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Abstract As secretary of state, Dean Acheson had used the sudden end to the U.S. atomic monopoly in August 1949, when the first Soviet test was detected, to initiate a reappraisal of security policy. One outcome was the development of thermonuclear weapons in order to maintain superiority for as long as possible; another, adopted after the start of the Korean War, was a sustained rearmament program to reduce dependence upon this superiority before its inevitable loss. The Eisenhower administration criticized this stance as unnecessarily expensive in its reliance on conventional forces and constraining in its reluctance to exploit America’s prime strategic asset. This was summed up by the stalemate in Korea, where self-imposed limitations left the Americans fighting in a framework that played to the communists’ advantages. In a famous speech of January 1954 Dulles asserted, ‘‘The way to deter aggression is for the free community to be willing and able to respond vigorously at places and with means of its own choosing.’’1 America’s means of choice appeared to be ‘‘massive retaliatory power’’ (hence the policy’s label of ‘‘massive retaliation’’). To its critics, the obvious flaw lay in the excessive dependence placed on the credibility of U.S. nuclear threats, even as it declined when the Soviet Union acquired its own massive retaliatory power. Prominent among the policy’s critics was Acheson, who denounced it as an ‘‘Orwellian attempt to persuade the country that it got stronger by getting weaker,’’ charging that it would preclude the United States from making a forceful response to local aggression.2
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Dispinar, Derya. "Melt Quality Assessment." In Encyclopedia of Aluminum and Its Alloys. CRC Press, 2019. http://dx.doi.org/10.1201/9781351045636-120052503.

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It is well known that the reaction of liquid aluminum with the moisture in the environment results in two products: aluminum oxide and hydrogen gas that dissolves in aluminum. Both of these products are considered to be detrimental to the properties of aluminum alloys. Therefore, test equipment has been developed to check the levels of these defects in the melt. Many of these involve expensive and consumable tools. In addition, an experienced personnel may be required to interpret the results. Nonetheless, aluminum oxide is harmless as long as it remains on the surface. The problem begins when this oxide is entrained into the liquid aluminum such as turbulence during transfer or mold filling in a non-optimized design. This can only happen by folding of the oxide. During this action, rough surface of the oxides comes in contact to form no bonds. These defects are known as bifilms that have certain characteristics. First, they act as cracks in the cast parts since they are oxides. It is important to note that aluminum oxide has thin amorphous oxide (known as young oxides) and thick crystalline oxide (γ-Al2O3) that may be formed in a casting operation. Second, almost zero force is required to open these bifilms due to the unbonded folded oxide skins. Thus, these defects can easily form porosity by unravelling during solidification shrinkage. On the other hand, the formation of porosity by hydrogen is practically impossible. Theoretically, hydrogen has high solubility in the liquid but it has significantly low solubility in solid aluminum. Thus, it is suspected that hydrogen is rejected from the solidification front to form hydrogen gas and porosity. However, the hydrogen atom has the smallest atomic radii and high diffusibility. Therefore, segregation of hydrogen in front of the growing solid is difficult. In addition, the energy required for hydrogen atoms to segregate and form hydrogen gas molecule is around 30,000 atm. Under these conditions, porosity formation by hydrogen is not likely to be achieved. Hydrogen probably stays in a supersaturated state or diffuses homogeneously through the cast part. The effect of hydrogen can only be seen when it can diffuse into the unbonded gap between the bifilms to open them up to aid the unravelling of bifilms to form porosity. This phenomenon can be easily detected by a very simple test called reduced pressure test. When a sample is solidified under vacuum, the bifilms start to open up. Since all porosity is formed by bifilms, the cross section of the sample solidified under vacuum can be analyzed by means of image analysis software. The sum of maximum length of pores can be measured as an indication of melt quality. Since bifilms are the most detrimental defects, this value is called “bifilm index” given in millimetres, which makes this test the only test that can quantify aluminum melt quality in such detail including both the effects of bifilms and hydrogen together. Several Al-Si alloys were used at various conditions: degassing with lance, ceramic diffusers, and graphite rotary has been compared. Gravity sand casting, die casting, and low-pressure die casting methods were evaluated. The effect of grain refiners and modifiers was studied. And the evolution of the bifilm index has been presented.
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"Synthetic Methods for Primary Anilines." In Methods and Strategies for C–N Bond Formation Reactions. Royal Society of Chemistry, 2023. http://dx.doi.org/10.1039/bk9781837672615-00145.

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Aryl amines have received significant interest because these compounds widely exist in the structural backbones of ligands, pharmaceuticals, agrochemicals, natural products, and functional materials. In N-arylation reactions, several types of organic electrophile coupling partners such as (pseudo)halides (Ullmann-type and Buchwald–Hartwig couplings) and boronic acids (Chan–Lam coupling) are popular. The main synthetic methods for the preparation of these compounds involving N-arylation utilize aryl halides. Progress has been made with the coupling of arylating reagents which are less expensive than aryl halides, providing both a cost-effective and more efficient reaction route. For example, the process of C–H bond activation/functionalization, a step-efficient and atom-economical transformation, has emerged as a powerful strategy in C–N bond-forming reactions. Moreover, a transition-metal-free method for the N-arylation of amines using an aryne intermediate has been developed. This chapter focuses on recent advances in chemo- and regioselective N-arylation (either on one N-center or on the exocyclic N-site of the ring) or the selective arylation of amino alcohols without additional protection/deprotection using arylating reagents. This chapter provides an overview of arylating reagents for N-arylation reactions found in both basic and applied chemical research. The substrate scope, limitations, reaction mechanism, and chemoselectivity, as well as related control strategies of these reactions, are discussed. To the best of our knowledge, there has been no book about introducing arylating reagents to develop more efficient and environmentally friendly cross-coupling methods for the N-arylation of amines. We believe this critical review will provide necessary background information on the N-arylation of amines.
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Conference papers on the topic "Atomic expension"

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Heying, Matthew J., James H. Oliver, Sriram Sundararajan, Pranav Shrotriya, and Qingze Zou. "Virtual Training Simulator for Atomic Force Microscopy." In ASME 2005 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/detc2005-85477.

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Training novice users how to operate an Atomic Force Microscope (AFM) is expensive due to the cost of equipment and the time required to train users in a hands-on learning environment. Training large groups of users simultaneously presents a problem because usually only one AFM is available for use. To alleviate this problem, a virtual training simulator for AFM training has been developed. The training simulator is a Windows-based software program designed to allow users to simulate basic AFM operation on a PC. Instructors can use this tool to demonstrate the exact same instruction that a use
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Laflin, Jeremy, Mohammad Poursina, Kurt Anderson, and Daniel Koerner. "Implementation Issues With Far Field Approximations With Multi-Resolution Biopolymer Simulations." In ASME 2013 2nd Global Congress on NanoEngineering for Medicine and Biology. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/nemb2013-93098.

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Current strategies to simulate the dynamic behavior of large molecular systems involve either computationally expensive fully atomistic models, or lower resolution models that have been coarsened in some manner. Coarsening is nominally accomplished by grouping tightly bonded atoms that have little relative motion. Traditionally this accomplished by treating a region as pseudo-atom and connecting it to other psuedo-atoms to reproduce the system. Alternatively this can be done with a multibody-based approach characterizing the regions as rigid or flexible bodies [1]–[6].
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Holmquist, Lars Erik. "Bits are Cheap, Atoms are Expensive: Critiquing the Turn Towards Tangibility in HCI." In CHI '23: CHI Conference on Human Factors in Computing Systems. ACM, 2023. http://dx.doi.org/10.1145/3544549.3582744.

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Bashash, Saeid, Reza Saeidpourazar, and Nader Jalili. "Development of a High-Speed Laser-Free Atomic Force Microscopy." In ASME 2009 Dynamic Systems and Control Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/dscc2009-2742.

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To reduce the cost and improve the speed of Atomic Force Microscopy (AFM) in molecular scale imaging of materials, we propose a laser-free AFM scheme augmented with an accurate control strategy for its scanning axes. It employs a piezoresistive sensing device with a high level of accuracy to avoid using the bulky and expensive laser interferometer. Change in the resistance of piezoelectric layer due to the deflection of microcantilever caused by the variation of surface topography is monitored through a Wheatstone bridge. Hence, it captures the surface topography without the use of laser and w
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Bansal, Ankit, Michael F. Modest, and Deborah Levin. "Narrow-Band k-Distribution Database for Atomic Radiation in Hypersonic Nonequilibrium Flows." In ASME 2009 Heat Transfer Summer Conference collocated with the InterPACK09 and 3rd Energy Sustainability Conferences. ASMEDC, 2009. http://dx.doi.org/10.1115/ht2009-88120.

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Full-spectrum k-distribution (FSK) and multi-group FSK approaches make it possible to evaluate radiative fluxes at a fraction of the cost needed for line-by-line calculations. However, the required k-distributions need to be assembled from accurate absorption coefficient data for each flow condition, which is computationally expensive. An accurate and compact narrow-band k-distribution database has been developed for the most important species encountered in hypersonic nonequilibrium flow. The database allows users to calculate desired full-spectrum k-distributions through look-up and interpol
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Bender, H. A., A. M. Eligon, A. Hanzo, and W. T. Silfvast. "Velocity Characterization of Target Debris from a Laser Produced Plasma Utilizing a “Time-of-Flight” Technique." In Soft X-Ray Projection Lithography. Optica Publishing Group, 1993. http://dx.doi.org/10.1364/sxray.1993.tud.13.

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The generation of significant amounts of target debris from laser produced plasmas is well known and has been characterized in terms of quantity, particle sizes, rate of deposition on surfaces, and other parameters for conditions relevant to soft x-ray projection lithography (SXPL).1 This debris will be detrimental to the condenser and/or illumination optics in an SXPL system. Of the three categories of debris, high velocity ions, neutral atoms, and particulates (or clusters), it is the latter that is quite difficult to control and potentially the most damaging. It has been shown that atomic a
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Cordeiro, Jhonatam, and Salil Desai. "Process Parameter Studies of Molecular Dynamics Models to Control Substrate Wettability." In ASME 2015 International Manufacturing Science and Engineering Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/msec2015-9282.

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Nanotechnology is being used to solve many engineering problems in the fields of electronics, medicine and energy. However, nanomanufacturing and nano-characterization of materials usually require time, specialized machinery and laboratory facilities that are unavailable or expensive to operate. The use of classical computer simulation of materials, such as finite element analysis has limited representation at the nanoscale, because they fail to consider the atomic configurations and forces. This research presents the use of Molecular Dynamics modeling to characterize materials at the nanoscal
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Shaw, R. W., J. P. Young, and D. H. Smith. "Tunable Diode Lasers for Resonance Ionization Mass Spectrometry and Very High Resolution Atomic Spectroscopy." In Laser Applications to Chemical Analysis. Optica Publishing Group, 1990. http://dx.doi.org/10.1364/laca.1990.mb3.

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Many tunable laser-based analytical techniques developed over the past decade have remained research curiosities. The sensitivity and selectivity limits that have been demonstrated using these techniques are impressive. The lasers required for their implementation, however, are either too expensive or too complicated for routine settings. The advent of inexpensive, simple GaAlAs diode lasers offers the hope that this situation can be improved. These devices emit in the near infrared spectral region (670 - 850 nm) at typical powers of 5 to 30 mW. They generate coherent output beams and are tuna
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Fox, R. W., L. Hollberg, S. Waltman, K. P. Petrov, and F. K. Tittel. "Extending Wavelength Coverage and Spectroscopic Applications of Diode Lasers." In Laser Applications to Chemical and Environmental Analysis. Optica Publishing Group, 1996. http://dx.doi.org/10.1364/lacea.1996.lwc.3.

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Atomic spectroscopy of an electronic transition from the ground state often requires a tunable blue or UV source. Traditionally one approach in the laboratory has been to double or sum-frequency mix pulsed or CW-dye lasers to obtain the necessary wavelength. These lasers and nonlinear crystals such as LiNbO3, and LiIO3, have also been used in difference frequency experiments to reach the molecular vibrational bands in the infrared. However, these laboratory lasers suffer the well known litany of size, cost and complexity when compared to solid-state diode lasers. To reach these wavelength regi
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Yoon, Sung-Hwan, Jun S. Lee, Ji-Sun Im, et al. "Effect of Tooling Surface Roughness in Micro-Injection Molding." In ASME 2008 International Manufacturing Science and Engineering Conference collocated with the 3rd JSME/ASME International Conference on Materials and Processing. ASMEDC, 2008. http://dx.doi.org/10.1115/msec_icmp2008-72093.

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Quality of tooling surface has been considered as one of the important factors defining the injection molded part quality. Therefore, surface polishing has been an important and relatively expensive step in conventional mold making process. Although the poor surface quality impacts the product quality when molding macroscale parts, it becomes more significant with sub-micrometer features. Previous micro injection molding research result has indicated that rough tooling surface may cause polymer adhesion on the tooling surface. To evaluate the effect of roughness, optical grade polycarbonate wa
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Reports on the topic "Atomic expension"

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Kolodziejczyk, Bart. Unsettled Issues Concerning the Use of Green Ammonia Fuel in Ground Vehicles. SAE International, 2021. http://dx.doi.org/10.4271/epr2021003.

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While hydrogen is emerging as a clean alternative automotive fuel and energy storage medium, there are still numerous challenges to implementation, such as the economy of hydrogen production and deployment, expensive storage materials, energy intensive compression or liquefaction processes, and limited trial applications. Synthetic ammonia production, on the other hand, has been available on an industrial scale for nearly a century. Ammonia is one of the most-traded commodities globally and the second most-produced synthetic chemical after sulfuric acid. As an energy carrier, it enables effect
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