Relevant bibliographies by topics / Protons

Academic literature on the topic 'Protons'

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Published: 4 June 2021
Last updated: 29 July 2024

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Journal articles on the topic "Protons"

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Abdallat, Mahmoud, Abdallah Barjas Qaswal, Majed Eftaiha, Abdel Rahman Qamar, Qusai Alnajjar, Rawand Sallam, Lara Kollab, et al. "A mathematical modeling of the mitochondrial proton leak via quantum tunneling." AIMS Biophysics 11, no. 2 (2024): 189–233. http://dx.doi.org/10.3934/biophy.2024012.

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<abstract> <p>The mitochondrion is a vital intracellular organelle that is responsible for ATP production. It utilizes both the concentration gradient and the electrical potential of the inner mitochondrial membrane to drive the flow of protons from the intermembrane space to the matrix to generate ATP via ATP-synthase. However, the proton leak flow, which is mediated via the inner mitochondrial membrane and uncoupling proteins, can reduce the efficiency of ATP production. Protons can exhibit a quantum behavior within biological systems. However, the investigation of the quantum behavior of protons within the mitochondria is lacking particularly in the contribution to the proton leak. In the present study, we proposed a mathematical model of protons tunneling through the inner mitochondrial membrane and the mitochondrial carrier superfamily MCF including uncoupling proteins UCPs and the adenine nucleotide translocases ANTs. According to the model and its assumptions, the quantum tunneling of protons may contribute significantly to the proton leak if it is compared with the classical flow of protons. The quantum tunneling proton leak may depolarize the membrane potential, hence it may contribute to the physiological regulation of ATP synthesis and reactive oxygen species ROS production. In addition to that, the mathematical model of proton tunneling suggested that the proton-tunneling leak may depolarize the membrane potential to values beyond the physiological needs which in turn can harm the mitochondria and the cells. Moreover, we argued that the quantum proton leak might be more energetically favorable if it is compared with the classical proton leak. This may give the advantage for quantum tunneling of protons to occur since less energy is required to contribute significantly to the proton leak compared with the classical proton flow.</p> </abstract>
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Akhmedov, Murodzhon, Bülent Çatay, and Mehmet Serkan Apaydın. "Automating unambiguous NOE data usage in NVR for NMR protein structure-based assignments." Journal of Bioinformatics and Computational Biology 13, no. 06 (December 2015): 1550020. http://dx.doi.org/10.1142/s0219720015500201.

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Nuclear Magnetic Resonance (NMR) Spectroscopy is an important technique that allows determining protein structure in solution. An important problem in protein structure determination using NMR spectroscopy is the mapping of peaks to corresponding amino acids, also known as the assignment problem. Structure-Based Assignment (SBA) is an approach to solve this problem using a template structure that is homologous to the target. Our previously developed approach Nuclear Vector Replacement-Binary Integer Programming (NVR-BIP) computed the optimal solution for small proteins, but was unable to solve the assignments of large proteins. NVR-Ant Colony Optimization (ACO) extended the applicability of the NVR approach for such proteins. One of the input data utilized in these approaches is the Nuclear Overhauser Effect (NOE) data. NOE is an interaction observed between two protons if the protons are located close in space. These protons could be amide protons, protons attached to the alpha-carbon atom in the backbone of the protein, or side chain protons. NVR only uses backbone protons. In this paper, we reformulate the NVR-BIP model to distinguish the type of proton in NOE data and use the corresponding proton coordinates in the extended formulation. In addition, the threshold value over interproton distances is set in a standard manner for all proteins by extracting the NOE upper bound distance information from the data. We also convert NOE intensities into distance thresholds. Our new approach thus handles the NOE data correctly and without manually determined parameters. We accordingly adapt NVR-ACO solution methodology to these changes. Computational results show that our approaches obtain optimal solutions for small proteins. For the large proteins our ant colony optimization-based approach obtains promising results.
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Pavković, Nemanja, Branislav Milovanović, Ana Stanojević, Mihajlo Etinski, and Milena Petković. "Proton leap: shuttling of protons onto benzonitrile." Physical Chemistry Chemical Physics 24, no. 6 (2022): 3958–69. http://dx.doi.org/10.1039/d1cp04338b.

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Gutta, Pradeep, and Dean J. Tantillo. "Proton Sandwiches: Nonclassical Carbocations with Tetracoordinate Protons." Angewandte Chemie International Edition 44, no. 18 (April 29, 2005): 2719–23. http://dx.doi.org/10.1002/anie.200461915.

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Gutta, Pradeep, and Dean J. Tantillo. "Proton Sandwiches: Nonclassical Carbocations with Tetracoordinate Protons." Angewandte Chemie 117, no. 18 (April 29, 2005): 2779–83. http://dx.doi.org/10.1002/ange.200461915.

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Weksler, Meir. "Protons." Medical Journal of Australia 199, no. 11 (December 2013): 801. http://dx.doi.org/10.5694/mja13.10908.

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Schiavilla, R., V. G. J. Stoks, W. Glöckle, H. Kamada, A. Nogga, J. Carlson, R. Machleidt, et al. "Weak capture of protons by protons." Physical Review C 58, no. 2 (August 1, 1998): 1263–77. http://dx.doi.org/10.1103/physrevc.58.1263.

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Lísal, Jiří, and Merritt Maduke. "Proton-coupled gating in chloride channels." Philosophical Transactions of the Royal Society B: Biological Sciences 364, no. 1514 (October 28, 2008): 181–87. http://dx.doi.org/10.1098/rstb.2008.0123.

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The physiologically indispensable chloride channel (CLC) family is split into two classes of membrane proteins: chloride channels and chloride/proton antiporters. In this article we focus on the relationship between these two groups and specifically review the role of protons in chloride-channel gating. Moreover, we discuss the evidence for proton transport through the chloride channels and explore the possible pathways that the protons could take through the chloride channels. We present results of a mutagenesis study, suggesting the feasibility of one of the pathways, which is closely related to the proton pathway proposed previously for the chloride/proton antiporters. We conclude that the two groups of CLC proteins, although in principle very different, employ similar mechanisms and pathways for ion transport.
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Ardalan, Afshan, Matthew D. Smith, and Masoud Jelokhani-Niaraki. "Uncoupling Proteins and Regulated Proton Leak in Mitochondria." International Journal of Molecular Sciences 23, no. 3 (January 28, 2022): 1528. http://dx.doi.org/10.3390/ijms23031528.

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Higher concentration of protons in the mitochondrial intermembrane space compared to the matrix results in an electrochemical potential causing the back flux of protons to the matrix. This proton transport can take place through ATP synthase complex (leading to formation of ATP) or can occur via proton transporters of the mitochondrial carrier superfamily and/or membrane lipids. Some mitochondrial proton transporters, such as uncoupling proteins (UCPs), transport protons as their general regulating function; while others are symporters or antiporters, which use the proton gradient as a driving force to co-transport other substrates across the mitochondrial inner membrane (such as phosphate carrier, a symporter; or aspartate/glutamate transporter, an antiporter). Passage (or leakage) of protons across the inner membrane to matrix from any route other than ATP synthase negatively impacts ATP synthesis. The focus of this review is on regulated proton transport by UCPs. Recent findings on the structure and function of UCPs, and the related research methodologies, are also critically reviewed. Due to structural similarity of members of the mitochondrial carrier superfamily, several of the known structural features are potentially expandable to all members. Overall, this report provides a brief, yet comprehensive, overview of the current knowledge in the field.
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Gary, S. Peter, Michelle F. Thomsen, Lin Yin, and Dan Winske. "Electromagnetic proton cyclotron instability: Interactions with magnetospheric protons." Journal of Geophysical Research: Space Physics 100, A11 (November 1, 1995): 21961–72. http://dx.doi.org/10.1029/95ja01403.

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Dissertations / Theses on the topic "Protons"

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Gurke, Johannes. "Protons and Photons." Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/19747.

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Gegenstand dieser Arbeit ist die Frage wie thermische und photochemische Gleichgewichte verbunden werden können und sich gegenseitig beeinflussen. Dazu wurden zwei Projekte bearbeitet, zum einen das Konzept der „säure-katalysierten Zykloreversion“ und zum anderen das Konzept der „licht-induzierten pKs Veränderung“. Im ersten Konzepte wurde eine extern steuerbare, thermische Rückreaktion genutzt, um die Zusammensetzung im photostationären Zustand zu kontrollieren. Durch Zugabe von katalytischen Mengen einer starken Säure wurde die Ringöffnung eines Diarylethens, welches mit einem Flurenol substituiert ist, eingeleitet. Der zugrundeliegende Prozess wurde kinetisch und thermodynamisch, sowohl durch Experimente als auch durch computergestützte Rechnungen beschrieben. Eine säure-induzierte Dehydratation öffnet einen neuen Reaktionspfad, wodurch die normalerweise sehr hohe Reaktionsbarriere der Ringöffnung umgangen werden kann. Die quantitative Umsetzung mit Säure führt zu einer kompletten Löschung der photochemischen Reaktivität. Dieses Konzept kann in der Speicherung von Lichtenergie in photochromen metastabilen Systemen genutzt werden. Durch die Nutzung von 3-H-Thiazol-2-on als Rest im Diarylethen konnte eine signifikante pKs Änderung von 2.8 Einheiten in wässriger Umgebung erreicht werden. Dabei wurden zwei Säure-Base Gleichgewichtssysteme miteinander gekoppelt, welche an der thermischen Umwandlung gehindert sind, jedoch photochemisch ineinander überführt werden können. Des Weiteren wurde eine hohe Abhängigkeit der Quantenausbeute von dem Protonierung festgestellt. Diese wurde genutzt um die Performance der Photoreaktion zu beeinflussen. Die Beeinflussung der Photoreaktion erfolgt nicht durch Veränderung der Energetik des Grundzustandes, sondern durch Veränderung der Potentialhyperfläche des angeregten Zustandes. Durch neue molekulare Designs konnte eine signifikante Verbesserung im Vergleich zu bekannter Molekülen und Konzepten in beiden Projekten erreicht werden.
Two projects are implemented in this work, which share the goal to interconnect acid-base equilibria with the photoreactions of diarylethene (DAE) photoswitches. This task can be divided into two logic questions: How can photochemical equilibria be controlled or rather influenced via an acidic or basic stimulus and how can a photoreaction induce control over an acid-base equilibrium? In the first project, “Acid-Catalyzed Cycloreversion”, an externally tunable thermal back reaction was designed to influence a photochemical equilibrium. Upon addition of catalytic amounts of acid, a closed DAE carrying a fluorenol moiety undergoes facile thermal ring opening. The underlying thermodynamics and kinetics of the entire system have been analyzed experimentally as well as computationally. Appling an excess of acid leads to a complete inhibition of the photoreaction through the introduction of a charge-transfer. My work suggests that acid catalysis provides a useful tool to bypass thermal barriers, potentially usable to efficiently trigger the release of light energy stored in photoswitches. In the second project, entitled “Light-induced pKa Modulation”, a significant pKa change of 2.8 units in an aqueous medium was achieved by connecting two different acid-base equilibria. These thermodynamic equilibria are separated by a high activation barrier, overcome by a photoreaction. The developed system which is based on the incorporation of a 3 H thiazol 2 one moiety into a DAE, shows a strong dependency of the quantum yield and hence, of the photoconversion on the protonation state. Adjusting the pH within the range of the pKa change, a substantial enhancement of the photoconversion is achievable as well as a distinct alteration of the performance of the photoreaction. This effect does not originate from different reaction paths on the ground state potential energy surface (PES), but results presumably from a protonated state dependent difference in the excited PES.
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JAFER, RASHIDA. "Laser plasma protons and applications in cancer therapy and proton radiography." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2009. http://hdl.handle.net/10281/7457.

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Recent developments in high power, ultrashort pulse laser systems enable laser intensities beyond 10^21 W/cm^2 to be achieved. When focused onto thin foil targets, plasmas with extremely high electrostatic fields (>10^12V/m) are produced, resulting in the acceleration of protons/ions to very high energies (~60MeV). During my PhD, I have worked on experimental investigations into proton acceleration driven by high power laser pulses. Key to successful deployment of laser proton sources one one side is getting higher proton energies through to achieve the ultimate goal of realising table top machines for the treatment of cancer and on the other side, optimising the beam quality, an objective that was of the main motivation for my PhD work. My two main achievements were: 1. The production of bright, ultrashort and radially smooth pulsed proton beams using laser heating of pre-plasmas formed with long (nanosecond) pulses with ultrahigh intensity picosecond pulses. 2. Use of these beams to study the ultrafast dynamics of target implosion under intense laser irradiation The experiments on proton acceleration with the specific goal of controlling the proton beam quality by optical tool design, were performed at RAL. This scheme involves the use of multiple laser pulses to enhance and control the properties of beams of protons accelerated in ultra-intense laser irradiation of planar foil targets. Specifically, one laser pulse produces and controls the expansion of the target to enhance the energy coupling to the main (delayed) laser and/or drives shock deformation of the target to change the direction of the proton beam. The preplasma formed by this low intensity nanosecond beam (~ 0.5-5x10^12 W/cm^2) was used to enhance the laser absorption of the main (delayed) CPA (Chirped pulse amplified). The main CPA picosecond beam was used at high intensity (~ 4x 10^20 W /cm^2) to produce intense proton beams from the hydrogen rich target. The optimum intensity of the nanosecond beam was investigated and optimised to yield a very smooth and circular distribution of the proton beam achieved using a second long pulse laser at 5x10^12w/cm^2. The second achievement concerns an experiment also performed at RAL on proton radiography. As the laser based protons are characterised by small source size, high degree of collimation and short duration, they can be used in point projection backlighting schemes to perform radiography. In particular, I used this idea to perform radiography of a cylindrical target ~ 200µm long imploding under irradiation by long laser pulses of nanosecond duration. This allows measuring the degree of compression of the target as well as the stagnation time in the dynamic regime. The experiment took place in the framework of the HiPER project (the European High Power laser Energy Research facility Project). The final goal of the experiment was to study the transport of fast electron in cylindrical compressed target a subject of interest for fast ignition. In parallel to proton radiography x-ray radiography was used to compare the results. One of the specific advantages of using laser generated protons is that their spectrum is continuous upto a high energy cutoff. Because of their different time of flights protons proved to be very effective in revealing the implosion history of the target. In principle, the obtained implosion can be followed in time with a single shot sensitivity. Instead x-ray radiograph gives one image per laser shot at one fixed time and one has to make several shots in order to reveal the complete history of implosion. Another advantage of using proton radiography is a simpler experimental setup keeping imploding cylinder between proton target and proton detector on the same axis. Simulations of formation of proton images were made with the Monte Carlo MCNPX Code using the density profiles of the imploded cylinder obtained with the 2D-hydro CHIC code. A detailed study of Multiple Coulomb Scattering and Stopping Powers of the protons in low energy regimes for cold and warm matter was done to interpret the experimental results. Finally, I’m taking part in the analysis of experimental results obtained at the University of Rochester (USA) on the Omega-EP laser, and concerning magnetic field effect on the proton radiographs of a wired cone.
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Pilcher, John Victor. "Coincident proton decay of the continuum induced by 200 MeV protons on 12C." Doctoral thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/17190.

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Bibliography: p. 212-221.
Coincident protons from the reaction ¹²C(p,2p) at an incident proton energy of 200 Me V, have been measured using conventional particle telescopes. Data were acquired at nine pairs of angles (θ₂=20°, 45°, 70°, 95°, 120° and 145° for θ₁ =-20°, and θ₂=35°, 85° and 135° for θ₁ =-45°). An improved model, based on previous theoretical and experimental work, has been proposed to describe the reaction mechanism leading to the observed coincident proton yield from the nuclear continuum. This model considers an initial quasifree nucleon-nucleon interaction - described by a distorted wave impulse approximation (DWIA) treatment - between the incident proton and a single target nucleon, followed by the rescattering of the struck nucleon, which behaves as an intranuclear projectile, from the spectator part of the target nucleus. The validity of the DWIA treatment used in the continuum study, has been tested by analysing the kinematic regions of the coincident proton energy spectra corresponding to the knockout of protons from the outer lp3/2 orbital of ¹²C which do not undergo further interactions with the residual nucleus. Good agreement in shape has been found between the calculated and measured cross sections in the kinematic region of interest to the continuum study. An average spectroscopic factor of 1.1±0.3 was extracted. Except in the -20°,20° case, the DWIA treatment was found to be insensitive to the choice of the initial or final energy prescriptions for the two-body scattering approximation. Nonlocality effects were found to be small, changing the absolute value of spectroscopic factors by a maximum of 20%. Coincident continuum cross sections were extracted from the experimental data corresponding to the detection of protons at the θ₁ angles with energies of 70±5 MeV, 100±5 MeV and 130±5 MeV. Comparisons were made with calculations which modelled the proposed reaction mechanism in terms of a convolution integral over the DWIA cross sections describing the initial quasifree knockout process and experimental inelastic scattering probabilities describing the further multiple scattering interactions undergone by the knocked out nucleons. Good agreement has been found between the normalized calculated and measured continuum cross sections (spectroscopic factors varying from 0.8 to 2.3 between sets of data, depending on the kinematic region sampled and the prescription used for the two-body scattering approximation). It has been shown that contributions from nucleons that are knocked out both in- and out-of-plane in the initial quasifree process should be considered, and that the contribution from neutron knockout in the initial interaction is significant, ranging from 0.13 to 0.62 that of the proton knockout contribution.
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Roder, Ana Flávia Vidotti [UNESP]. "Estudo da interação de prótons com alvos não homogêneos, aplicados a tomografia com feixes de prótons." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/108789.

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Made available in DSpace on 2014-08-13T14:50:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-25Bitstream added on 2014-08-13T17:59:54Z : No. of bitstreams: 1 000769599_20160131.pdf: 256213 bytes, checksum: 5f511cbb596c1f707bc977be42246aaf (MD5) Bitstreams deleted on 2016-02-01T10:15:56Z: 000769599_20160131.pdf,. Added 1 bitstream(s) on 2016-02-01T10:16:46Z : No. of bitstreams: 1 000769599.pdf: 1800159 bytes, checksum: 4ba8b1a044e20855baf40d195fdc0c91 (MD5) Bitstreams deleted on 2016-06-15T18:56:31Z: 000769599_sub.pdf,. Added 1 bitstream(s) on 2016-06-15T18:57:10Z : No. of bitstreams: 1 000769599.pdf: 18986432 bytes, checksum: a3924b26321cd155af0495154ed8096f (MD5)
O tratamento do câncer através da irradiação com prótons tem se desenvolvido a amplamente, de maneira que a cada década o número de centros com essa tecnologia aumenta progressivamente. Entretanto, o planejamento da rotina de terapia ainda é realizado com imagens de raios-X, que pode causar incertezas quanto ao posicionamento preciso do feixe de prótons sobre o tumor devido à diferença de comportamento ao interagir com a matéria. Por isso, são necessários estudos que busquem o aprimoramento da tomografia computadorizada com prótons, que tem como principal função, determinar a posição do pico de Bragg com eficiência. Mas para se desenvolver essa técnica é preciso determinar a trajetória exata que a partícula percorre dentro do corpo do paciente, que é possível com simulações baseadas no método de Monte Carlo. Vários programas no mercado utilizam Monte Carlo para diferentes tipos de propósitos, dentre os que são voltados para o transporte do próton, estão: GEANT, FLUKA e MCNPX. Esse último foi o utilizado neste trabalho para avaliar a perturbação no feixe incidente de prótons em um meio heterogêneo, composto por água e material simulador de osso compacto (interfaces perpendiculares ao feixe). Além de um modelo formado por água e PMMA (interfases paralelas ao feixe) para avaliar o uso de fantomas desses materiais. Foram estudadas energia, posição e ângulo de saída dos prótons considerando somente partículas primárias e também para todas as partículas
Cancer treatment by irradiation with protons has been widely developed so that each decade the number of centers based on this technology increases progressively. However, the planning of routine therapy is performed with images of X- rays, which can cause uncertainties as to the precise positioning of the proton beam on the tumor due to the difference in behavior when interacting with matter. Therefore, it is necessary studying the improvement of computed tomography with protons, whose main function, determine the position of the Bragg peak efficiently. Nevertheless, to develop this technique it is necessary to determine the exact path that the particle travels through the patient's body, which is possible with simulations based on Monte Carlo method. There are several programs that use Monte Carlo for different types of purposes, among which are meant for the transport of the proton: GEANT, FLUKA and MCNPX. The third one was used in this work to evaluate the disturbance in the incident beam of protons in a heterogeneous medium composed of water and equipment simulator compact bone (beam direction perpendicular to the interface) and water-PMMA (beam parallel to the interface). The output energy, position and angle of the protons were studied considering only primary particles and for all particles
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Tripp, Robert D. "Elastic scattering of high-energy polarized protons by complex nuclei." Berkeley, Ca. : Lawrence Radiation Laboratory, 2975. http://catalog.hathitrust.org/api/volumes/oclc/549450172.html.

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Reinhardt, Sabine. "Detection of laser–accelerated protons." Diss., lmu, 2012. http://nbn-resolving.de/urn:nbn:de:bvb:19-155620.

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Galand, Marina. "Transport des protons dans l'ionosphère aurorale." Phd thesis, Université Joseph Fourier (Grenoble), 1996. http://tel.archives-ouvertes.fr/tel-00724355.

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Les électrons et les protons suprathermiques, issus du soleil et précipitant dans l'atmosphère des hautes latitudes, constituent une source d'énergie de l'ionosphère terrestre. Ces particules interagissent avec le gaz thermique ambiant par collisions. L'équation de Boltzmann, fournissant les flux de particules en altitude, énergie et angle d'attaque, permet une description des plus complètes du transport de ces particules. Nous la redémontrons dans le cas dissipatif, le plus général, et nous proposons une résolution originale des équations de transport des protons et des atomes d 'hydrogène, équations couplées via les réactions de changement de charge. Cette résolution, fondée sur l'introduction de forces dissipatives pour décrire la dégradation énergétique des particules précipitant, permet la prise en compte des redistributions angulaires, d'origine collisionnelle ou magnétique, jusqu'alors négligées. Pourtant, leur effet a été observé, depuis le sol, sur les émissions des atomes d 'hydrogène, comme en témoigne la composante, décalée vers le rouge, du profil Doppler selon le zénith magnétique. La résolution adoptée ici est validée par comparaison avec un autre modèle, dans le cas classique sans redistribution angulaire. L'influence de l'effet de miroir magnétique est discutée: cet effet ne semble pas pouvoir expliquer, à lui seul, le décalage vers le rouge observé. La redistribution angulaire collisionnelle doit jouer un rôle significatif. Enfin, une comparaison de notre modèle avec les données de la fusée Proton 1 est proposée.
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Kar, S. "Application of MeV laser-driven protons." Thesis, Queen's University Belfast, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426792.

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Mooser, Andreas [Verfasser]. "Der g-Faktor des Protons / Andreas Mooser." Mainz : Universitätsbibliothek Mainz, 2014. http://d-nb.info/1051353440/34.

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Johnson, Samantha. "Optimizing the ion source for polarized protons." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&amp.

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Beams of polarized protons play an important part in the study of the spin dependence of the nuclear force by measuring the analyzing power in nuclear reactions. The source at iThemba LABS produces a beam of polarized protons that is pre-accelerated by an injector cyclotron (SPC2) to a energy of 8 MeV before acceleration by the main separated-sector cyclotron to 200 MeV for physics research. The polarized ion source is one of the two external ion sources of SPC2. Inside the ion source hydrogen molecules are dissociated into atoms in the dissociator and cooled to a temperature of approximately 30 K in the nozzle. The atoms are polarized by a pair of sextupole magnets and the nucleus is polarized by RF transitions between hyperfine levels in hydrogen atoms. The atoms are then ionized by electrons in the ionizer. The source has various sensitive devices, which influence beam intensity and polarization. Nitrogen gas is used to prevent recombination of atoms after dissociation. The amount of nitrogen and the temperature at which it is used plays a very important role in optimizing the beam current. The number of electrons released in the ionizer is influenced by the size and shape of the filament. Optimization of the source will ensure that beams of better quality (a better current and stability) are produced.
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Books on the topic "Protons"

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author, Fields B. H., ed. Understanding protons. New York: Cavendish Square, 2016.

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Karlsson, Jenny. Functional and structural analysis of the membrane domain of proton-translocating Escherichia coli Transhydrogenase. Göteborg: Department of Chemistry, Biochemistry and Physices, Göteborg University, 2006.

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Lemmer, Boris. Bis(s) ins Innere des Protons. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-37714-3.

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Lemmer, Boris. Bis(s) ins Innere des Protons. Berlin, Heidelberg: Springer Berlin Heidelberg, 2018. http://dx.doi.org/10.1007/978-3-662-56748-7.

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Borka, D. Channeling of protons through carbon nanotubes. Hauppauge, N.Y: Nova Science Publishers, 2011.

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1936-, Davis E. A., and Cox S. F. J, eds. Protons and muons in materials science. London: Taylor & Francis, 1996.

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Tsun, Wu Tai, ed. Expanding protons: Scattering at high energies. Cambridge, Mass: MIT Press, 1987.

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George C. Marshall Space Flight Center., ed. Activation calculations for trapped protons below 200 MeV. Richmond, Ky: Eastern Kentucky University, Department of Physics and Astronomy, 1991.

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International, Symposium on Proton-emitting Nuclei (1st 1999 Oak Ridge Tenn ). Proton-emitting nuclei: PROCON '99, First International Symposium, Oak Ridge, TN, 7-9 October, 1999. Melville, N.Y: AIP, 2000.

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Herring, Andrew M. Fuel cell chemistry and operation. Washington, DC: American Chemical Society, 2010.

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Book chapters on the topic "Protons"

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Chang, David S., Foster D. Lasley, Indra J. Das, Marc S. Mendonca, and Joseph R. Dynlacht. "Protons." In Basic Radiotherapy Physics and Biology, 185–94. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-61899-5_18.

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Reames, Donald V. "Hydrogen Abundances and Shock Waves." In Solar Energetic Particles, 187–219. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-66402-2_9.

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AbstractHow well do protons fit into the abundance patterns of the other elements? Protons have Q = 1 and A/Q = 1 at all temperatures of interest. When does their relative abundance fit on the power law in A/Q defined by the elements with A/Q > 2? For small “pure” impulsive events, protons fit well, but for larger CME-associated impulsive events, where shock waves boost the intensities, protons are enhanced a factor of order ten by addition of seed protons from the ambient plasma. During most large gradual SEP events with strong shock waves, protons again fit the power law, but with weaker or quasi-perpendicular shock waves, dominated by residual impulsive seed particle abundances at high Z, again protons are enhanced. Proton enhancements occur when moderately weak shock waves happen to sample a two-component seed population with dominant protons from the ambient coronal plasma and impulsive suprathermal ions at high Z; thus proton-enhanced events are a surprising new signature of shock acceleration in jets. A/Q measures the rigidity dependence of both acceleration and transport but does not help us distinguish the two. Energy-spectral indices and abundances are correlated for most gradual events but not when impulsive ions are present; thus we end with powerful new correlations that probe both acceleration and transport.
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Breit, G., E. U. Condon, and R. D. Present. "Theory of Scattering of Protons by Protons." In Selected Scientific Papers of E.U. Condon, 249–82. New York, NY: Springer New York, 1991. http://dx.doi.org/10.1007/978-1-4613-9083-1_26.

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Russell, Bertrand. "Electrons and Protons." In The Analysis of Matter, 23–28. London: Routledge, 2022. http://dx.doi.org/10.4324/9781003308898-4.

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Lemmer, Boris, Benjamin Bahr, and Rina Piccolo. "Die Struktur des Protons." In Quirky Quarks, 249–52. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-50259-4_61.

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Cramer, William A., and David B. Knaff. "Photosynthesis: Photons to Protons." In Energy Transduction in Biological Membranes, 239–98. New York, NY: Springer New York, 1990. http://dx.doi.org/10.1007/978-1-4612-3220-9_6.

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Jensen, A. D., and P. Fossati. "Protons and Heavy Ions." In Salivary Gland Cancer, 195–211. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-02958-6_12.

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Jordt, Sven-Eric. "TRPV1, Regulation by Protons." In Encyclopedia of Pain, 4112–15. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-28753-4_4653.

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Averyn, Viktar S. "Short Refresher of Radiobiology." In Nuclear and Radiological Emergencies in Animal Production Systems, Preparedness, Response and Recovery, 13–27. Berlin, Heidelberg: Springer Berlin Heidelberg, 2021. http://dx.doi.org/10.1007/978-3-662-63021-1_2.

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AbstractThe atoms are built up of a nucleus, containing positive (protons) and neutral (neutrons) particles, surrounded by negative particles (electrons), circulating around the “atomic orbit”. The number of the protons in the nucleus is giving the atomic number of the element (usually labelled as “Z”), and the sum of the neutrons and protons in the nucleus is giving the atomic or mass number of the element (usually labelled as “A”). The number in the electrons in the atomic orbit is always equal to the number of protons in the nucleus. However, as the mass of the electrons is almost equal to zero, they do not influence the whole atomic mass.
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Careri, G., F. Bruni, and G. Consolini. "Protons in hydrated protein powders." In Nonlinear Excitations in Biomolecules, 337–48. Berlin, Heidelberg: Springer Berlin Heidelberg, 1995. http://dx.doi.org/10.1007/978-3-662-08994-1_25.

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Conference papers on the topic "Protons"

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Wang, Zujun, Shaoyan Huang, Minbo Liu, Benqi Tang, Zhigang Xiao, and Yong Zhang. "Simulation of CCD Degradation Induced by Protons Irradiation." In 18th International Conference on Nuclear Engineering. ASMEDC, 2010. http://dx.doi.org/10.1115/icone18-29302.

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The mechanisms of charge coupled devices (CCD) irradiated by protons are analyzed. The simulation models of ionization damage and displacement damage are developed. The charge transfer efficiency (CTE) decreased by proton irradiation is numerically simulated. The CTE degradation caused by different traps and by protons with different energies has been studied respectively. Both surface dark signals induced by proton ionization damage and bulk dark signals induced by proton displacement damage are numerically simulated. The variability of surface dark signals, bulk dark signals, and total dark signals with proton fluence is compared. The simulation results are in agreement with the experimental results of the relevant literatures.
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Chiu, Chuang-Pin, Peng-Yu Chen, and Che-Wun Hong. "Atomistic Analysis of Proton Diffusivity at Enzymatic Biofuel Cell Anode." In ASME 2006 4th International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2006. http://dx.doi.org/10.1115/fuelcell2006-97136.

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This paper investigates the proton diffusion phenomenon between the anode catalyst and the electrode in an enzymatic bio-fuel cell. The bio-fuel cell uses enzymatic organism as the catalyst instead of the traditional noble metal, like platinum. The fuel is normally the glucose solution. The fuel cell is membrane-less and produces electricity from the reaction taken place in the organism. When the biochemical reaction occurs, the protons and electrons are released in the solution. The electrons are collected by the electrode plate and are transported to the cathode through an external circuit, while the protons migrate to the cathode by the way of diffusion. Unfortunately, protons are easy to dissipate in the solution because the enzyme is immersed in the neutral electrolyte. It is an important issue of how to collect the protons effectively. In order to investigate the diffusion process of the protons, a molecular dynamics simulation technique was developed. The simulation results track the transfer motion of the protons near the anode. The diffusivity was evaluated from the trajectory. The research concludes that the higher the glucose concentration, the better the proton diffusivity. The enzyme promotes the electrochemical reaction; however, it also plays an obstacle in the proton diffusion path.
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Aslam, Ottupara Muhammed, Driaan Bisschoff, and Marius Potgieter. "The solar modulation of protons and anti-protons." In 36th International Cosmic Ray Conference. Trieste, Italy: Sissa Medialab, 2019. http://dx.doi.org/10.22323/1.358.1054.

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Cheng, Chin-Hsien. "Nano-Scale Transport Phenomena and Thermal Effect of the PEMFC Electrolyte." In ASME 2008 First International Conference on Micro/Nanoscale Heat Transfer. ASMEDC, 2008. http://dx.doi.org/10.1115/mnht2008-52323.

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This paper employed molecular dynamics (MD) simulation to investigate the transport phenomena and thermal effect at nano-scale inside fuel cell electrolyte. The material of the electrolyte was chosen to be Nafion® which is the most commonly used material for proton exchange membrane fuel cell (PEMFC). The transport of protons inside the electrolyte is one of the major issues that influencing the fuel cell performance. The structure of the Nafion® includes carbon-fluorine back bones and side chains (with SO3− attached at the end). Simulation results show that the transport of protons was confined to some specific regions. These specific regions (hydrophilic phase region) consist of water molecules, protons and sulfonated acid groups. Different hydration levels (3, 61.25, 9 and 15.375 H2O/SO3−) was also studied to test the sensitivity of the electrolyte water content on proton conduction. Higher water content shows greater proton mobility due to the larger water cluster size and more water clusters. The influence of the temperatures (333K, 343K and 353K) on proton mobility was due to different sizes of hydrophilic phase regions. Diffusion coefficients at various operation conditions were also evaluated and showed satisfactory agreement with the published experimental data.
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Eaton, Brandon, Michael R. von Spakovsky, Michael W. Ellis, Douglas J. Nelson, Benoit Olsommer, and Nathan Siegel. "One-Dimensional, Transient Model of Heat, Mass, and Charge Transfer in a Proton Exchange Membrane." In ASME 2001 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/imece2001/aes-23652.

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Abstract A transient, one-dimensional, model of the membrane of a proton exchange membrane fuel cell is presented. The role of the membrane is to transport protons from the anode to cathode of the fuel cell while preventing the transport of other reactants. The membrane is modeled assuming mono-phase, multi-species flow. For water transport, the principle driving forces modeled are a convective force, an osmotic force (i.e. diffusion), and an electric force. The first of these results from a pressure gradient, the second from a concentration gradient, and the third from the migration of protons from anode to cathode and their effect (drag) on the dipole water molecules. Equations are developed for the conservation of protons and water, the conservation of thermal energy, and the variation of proton potential within the membrane. The model is solved using a fully implicit finite difference approach. Results showing the effects of current density, pressure gradients, water and heat fluxes, and fuel cell start-up on water concentration, temperature, and proton potential across the membrane are presented.
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Cheng, Chin-Hsien, Shu-Feng Lee, and Che-Wun Hong. "Molecular Dynamics of Proton Exchange Inside a Nafion® Membrane." In ASME 2006 4th International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2006. http://dx.doi.org/10.1115/fuelcell2006-97135.

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The proton transfer mechanism is the fundamental principle of how the proton exchange membrane fuel cell (PEMFC) works. This paper develops a molecular dynamics technique to simulate the transfer mechanism of the hydrogen protons inside a Nafion 117 membrane. The realistic polymer structure of the Nafion is extremely huge and very complex, it is simplified to be a repeated structure with part of the major carbon-fluoride backbone and a side chain with radicals of SO3− in this paper. Water molecules were assigned to distribute between side chains randomly. The simulation package of DLPOLY was employed as the platform. Simulation results show that the water molecules will cluster together due to the polarization characteristics, and the clusters are attracted by the side chain of the membrane electrolyte. Hydrogen protons are then transferred from one side chain to another through the water clusters. The migration process of the hydrogen protons within the membrane is a function of the water uptakes and many other factors. They are investigated to further improve the ionic conduction of the fuel cell membrane.
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Mart, T. "Are protons nonidentical fermions?" In 3RD INTERNATIONAL CONFERENCE ON THEORETICAL AND APPLIED PHYSICS 2013 (ICTAP 2013). AIP Publishing LLC, 2014. http://dx.doi.org/10.1063/1.4897090.

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Tannenbaum, Michael J. "Polarized protons at RHIC." In Polarized Collider Workshop. AIP, 1991. http://dx.doi.org/10.1063/1.40481.

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Soares, Mara Senghi, Roberto Fiore, Igor Ivanov, Alessandro Papa, and Jacques Soffer. "Leading Protons at HERA." In DIFFRACTION 2008: International Workshop on Diffraction in High Energy Physics. AIP, 2009. http://dx.doi.org/10.1063/1.3122160.

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Galea, R. "Frictional Cooling of Protons." In NEUTRINO FACTORIES AND SUPERBEAMS: 5th International Workshop on Neutrino Factories and Superbeams; NuFact 03. AIP, 2004. http://dx.doi.org/10.1063/1.1818444.

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Reports on the topic "Protons"

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Erdmann, Martin. Lebensdauer des Farbigen Protons in der Myon-Proton-Streuung. Office of Scientific and Technical Information (OSTI), January 1990. http://dx.doi.org/10.2172/1426711.

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Hershcovitch, A., and Y. Lee. TRAPPING DECELERATED ANTI-PROTONS. Office of Scientific and Technical Information (OSTI), March 1987. http://dx.doi.org/10.2172/1151187.

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Bunce, G. Polarized protons and RHIC. Office of Scientific and Technical Information (OSTI), December 1991. http://dx.doi.org/10.2172/5828406.

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Zhao X. F. and S. Lee. Resonance Jumping for Polarized Protons. Office of Scientific and Technical Information (OSTI), May 1986. http://dx.doi.org/10.2172/1151166.

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Montag, C., L. Ahrens, M. Blaskiewicz, J. M. Brennan, K. A. Drees, W. Fischer, H. Huang, et al. High intensity protons in RHIC. Office of Scientific and Technical Information (OSTI), January 2012. http://dx.doi.org/10.2172/1039650.

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Montag C., L. Ahrens, M. Blaskiewicz, J. M. Brennan, K. A. Drees, W. Fischer, H. Huang, et al. High Intensity protons in RHIC. Office of Scientific and Technical Information (OSTI), May 2012. http://dx.doi.org/10.2172/1061993.

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Ruggiero, Alessandro G. Nuclear Fusion of Protons with Boron. Office of Scientific and Technical Information (OSTI), September 1992. http://dx.doi.org/10.2172/1118958.

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Peggs, S. Protons on Gold at Identical Rigidities. Office of Scientific and Technical Information (OSTI), September 1997. http://dx.doi.org/10.2172/1119525.

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Bleser E., P. Ingrassia, and J. Laster. Total Protons Incident on Booster Dump. Office of Scientific and Technical Information (OSTI), February 1993. http://dx.doi.org/10.2172/1131628.

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Maximon, Leonard C. Scattering of polarized photons by protons. Gaithersburg, MD: National Bureau of Standards, 1988. http://dx.doi.org/10.6028/nist.ir.88-3877.

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