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Charged Particle Dynamics Inside Electrostatic Quadrupole Deflection System with Circular Electrodes and Rotationally Symmetric Design

Abstract

This paper offers a theoretical study of special type of electrostatic quadrupole deflection system (EQDS) intended for ion beam optics. We deal with EQDS consisting of electrode pairs with rotational symmetry design. This systems was pre-designed for an ion beam modification and trajectory controlling. Basic assumptions for determination of transfer characteristics of such systems are analysed on the basic of charged particle dynamics.

We are especially interested in the electrostatic field distribution among electrodes inside the mentioned type of EQDS. Typical case of the Sturm-Liouville boundary value problem called Bessel`s differential equation arises in calculation of the electrostatic scalar potential with rotational symmetry. Bessel`s functions are particular solution of Laplace equation in this case. The scalar potential equations of motion for ions in this electrostatic field are found. The path of charge-particles in this field could be determined by solving the trajectory equation of motion in Cartesian coordinates.

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Characterization and Applications of Organic Coagulant KOHIDRAC

Abstract

Low cost, effective and water soluble organic coagulant is offered for the extraction of charged clay particles. Coagulation with KOHIDRAC results in simultaneous concentration and purification of the clay fraction. After treatment with KOHIDRAC the obtained clay samples were free of carbonates and feldspar. Moreover, the amount of quartz decreased significantly in finished samples. The proposed coagulant and the patented methodology can be successfully used as purification procedure or as pretreatment for qualitative and quantitative analysis of clay minerals. The possible structure of the active compound KOHIDRAC was investigated in this paper. Real applications of the coagulant were provided.

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SIMU-RAD programme: a learning tool for radiation (photons and charged particles) interaction

Abstract

Radiation education is necessary for a wide variety of people, such as radiation workers particularly for students of secondary school and higher education institution who learn radiation sciences. The fact that we could not see or feel radiation makes it difficult to understand it. The use of radiation trajectories shown on a personal computer should be useful to overcome this difficulty. In order to understand radiation behaviour inside the material, we have developed a Simu-Rad (Copyright: LY2018002738) by using Monte Carlo simulation programme. One who has no programming knowledge is able to simulate photons in a material through the developed programme. The program could become a computer aided learning tool for radiation related courses. We aim to facilitate lecturer from ‘The Traditional Classroom’ to ‘The Flipped Classroom’ for radiation education concerning in the era of IR 4.0. To validate our radiation simulator, we calculate photon linear attenuation coefficient (µ) of an aluminium material which commonly used as a filter in diagnostic radiology. µ is one of the main characteristics to understand how the radiation attenuated inside the materials. We calculate at energy photon of 662 keV (Cs-137 radiation source) to compare our results of µ with the XCOM database. Consequently, the results from the developed simulator comparable with the database verified our programme to be used for radiation study.

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Experiment Plan as a Discreet System Equilibrium State

: http://www.osti.gov/scitech/servlets/purl/7091452/ [4] P. Audze and V. Eglājs, “New approach to the design of multifactor experiments,” Problems of Dynamics and Strengths, 35 ed. Riga: Zinatne Publishing House, 1977, pp. 104–107. [5] N. Kante and J. Lavendels, “Obtaining The Plan Of Experiments, On The Basis Of Modeling Of Interaction Of Charged Particles” in International Conference on “Theory and practice of simulation modeling and creation of simulators: the accumulation and processing of information, information models, information tools” , Penza

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Application of instruments of nuclear physics to the calculation of theoretical dose distributions in various organs of the human body for beams used in hadrontherapy

References 1. Particle Therapy Co-Operative Group. (2014). Patient statistics per end of 2013 . Retrieved August 15, 2014, from http://www.ptcog.ch/archive/patient/_statistics/ . 2. Durante, M., & Loeffler, J. (2010). Charged particles in radiation oncology. Nat. Rev. Clin. Oncol ., 7 (1), 37–43. DOI: 10.1038/nrclinonc.2009.183. 3. Schulz-Ertner, D., Jäkel, O., & Schlegel, W. (2006). Radiation therapy with charged particles. Semin. Radiat. Oncol ., 16 (4), 249–259. DOI: 10.1016/j.semradonc.2006.04.008. 4. Ziegler, J. (2013). SRIM

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A method on theoretical simulation of chromosome breaks in cells exposed to heavy ions

References Kraft G. Tumor therapy with heavy charged particles. Prog Part Nucl Phys 2000; 45: 473-544. Kawata T, Gotoh E, Durante M, Wu H, George K, Furusawa Y, et al. High-LET radiation-induced aberrations in prematurely condensed G 2 chromosome of human fibroblasts. Int J Radiat Biol 2000; 76: 929-37. Kawata T, Durante M, Frusawa Y, George K, Takai N, Wu H, et al. Dose-response of initial G 2 -chromatid breaks induced in normal human fibroblasts by heavy ions. Int J Radiat

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A BGK model for charge transport in graphene

Abstract

The classical Boltzmann equation describes well temporal behaviour of a rarefied perfect gas. Modified kinetic equations have been proposed for studying the dynamics of different type of gases. An important example is the transport equation, which describes the charged particles flow, in the semi-classical regime, in electronic devices. In order to reduce the difficulties in solving the Boltzmann equation, simple expressions of a collision operator have been proposed to replace the standard Boltzmann integral term. These new equations are called kinetic models. The most popular and widely used kinetic model is the Bhatnagar-Gross-Krook (BGK) model. In this work we propose and analyse a BGK model for charge transport in graphene.

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On the Relativistic Correction of Particles Trajectory in Tandem Type Electrostatic Accelerator

. 5. EINSTEIN, A. 1907. ¨Uber das Relativit¨ats Prinzip und die aus demselben gezogenen Folgerungen. Jahrbuch der Radioaktivit¨at und Elektronik, 4, pp. 411 - 462. 6. MINKOWSKI, H. 1915. Ann. Phys. Lpz. 47, 927. 7. BORN, M. 1909. Ann. Phys. Lpz. 30, 1. 8. LANDAU, L., LIFSHITZ, E. 1971. The Classical Theory of Fields. Course of Theoretical Physics, Volume 2. Pergamon: Addison-Wesley. 9. ROHRLICH, F. 2007. Classical Charged Particles. 3rd edition. London: World Scientific. 10. LYLE, S

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Performance Comparison of Hybrid Electromagnetism-Like Mechanism Algorithms with Descent Method

Abstract

Electromagnetism-like Mechanism (EM) method is known as one of metaheuristics. The basic idea is one that a set of parameters is regarded as charged particles and the strength of particles is corresponding to the value of the objective function for the optimization problem. Starting from any set of initial assignment of parameters, the parameters converge to a value including the optimal or semi-optimal parameter based on EM method. One of its drawbacks is that it takes too much time to the convergence of the parameters like other meta-heuristics. In this paper, we introduce hybrid methods combining EM and the descent method such as BP, k-means and FIS and show the performance comparison among some hybrid methods. As a result, it is shown that the hybrid EM method is superior in learning speed and accuracy to the conventional methods.

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Electric Polarity of Cigarette Mainstream Smoke / Die elektrischen Ladungen des Hauptstromrauches von Cigaretten

Abstract

The electric polarity of cigarette mainstream smoke depending on the remaining length of the cigarette was determined using two different devices. Furthermore the concentrations of positive and negative charges in the smoke were dimensionally measured. The results show that positive as well as negative charges are existent in mainstream smoke with about the same concentration of 10-11 Amp × sec × cm-3. Moreover an apparatus is described which permits the isolation of only the positively or negatively charged part of the cigarette smoke aerosol. The contamination of one separated part by particles of the opposite charge is found to be less than 3 %. By use of this distribution chamber parts of condensate of both polarities were obtained. The total IR-spectra of these parts showed no distinct general difference in chemical composition of positively or negatively charged particles of cigarette smoke.

Open access