Relevant bibliographies by topics / Charge carriers dynamic

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Academic literature on the topic 'Charge carriers dynamic'

Author: Grafiati
Published: 9 March 2023
Last updated: 10 March 2023

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Journal articles on the topic "Charge carriers dynamic"

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Katayama, Kenji, Tatsuya Chugenji, and Kei Kawaguchi. "Charge Carrier Trapping during Diffusion Generally Observed for Particulate Photocatalytic Films." Energies 14, no. 21 (October 26, 2021): 7011. http://dx.doi.org/10.3390/en14217011.

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Photo-excited charge carriers play a vital role in photocatalysts and photovoltaics, and their dynamic processes must be understood to improve their efficiencies by controlling them. The photo-excited charge carriers in photocatalytic materials are usually trapped to the defect states in the picosecond time range and are subject to recombination to the nanosecond to microsecond order. When photo-excited charge carrier dynamics are observed via refractive index changes, especially in particulate photocatalytic materials, another response between the trapping and recombination phases is often observed. This response has always provided the gradual increase of the refractive index changes in the nanosecond order, and we propose that the shallowly trapped charge carriers could still diffuse and be trapped to other states during this process. We examined various photocatalytic materials such as TiO2, SrTiO3, hematite, BiVO4, and methylammonium lead iodide for similar rising responses. Based on our assumption of surface trapping with diffusion, the responses were fit with the theoretical model with sufficient accuracy. We propose that these slow charge trapping processes must be included to fully understand the charge carrier dynamics of particulate photocatalytic materials.
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Du, Luchao, Xiaoping Shi, Menghan Duan, and Ying Shi. "Pressure-Induced Tunable Charge Carrier Dynamics in Mn-Doped CsPbBr3 Perovskite." Materials 15, no. 19 (October 8, 2022): 6984. http://dx.doi.org/10.3390/ma15196984.

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All-inorganic perovskite materials (CsPbX3) have attracted increasing attention due to their excellent photoelectric properties and stable physical and chemical properties. The dynamics of charge carriers affect the photoelectric conversion efficiencies of perovskite materials. Regulating carrier dynamics by changing pressure is interesting with respect to revealing the key microphysical processes involved. Here, ultrafast spectroscopy combined with high-pressure diamond anvil cell technology was used to study the generation and transfer of photoinduced carriers of a Mn-doped inorganic perovskite CsPbBr3 material under pressure. Three components were obtained and assigned to thermal carrier relaxation, optical phonon–acoustic phonon scattering and Auger recombination. The time constants of the three components changed under the applied pressures. Our experimental results show that pressure can affect the crystal structure of Mn-doped CsPbBr3 to regulate carrier dynamics. The use of metal doping not only reduces the content of toxic substances but also improves the photoelectric properties of perovskite materials. We hope that our study can provide dynamic experimental support for the exploration of new photoelectric materials.
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Moore, Kalani, Lynette Keeney, Clive Downing, Michele Conroy, and Ursel Bangert. "Charge Carriers in Dynamic Ferroelectric Domain Walls." Microscopy and Microanalysis 26, S2 (July 30, 2020): 1140–41. http://dx.doi.org/10.1017/s1431927620017079.

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Du, Sichao, Juxin Yin, Hao Xie, Yunlei Sun, Tao Fang, Yu Wang, Jing Li, et al. "Auger scattering dynamic of photo-excited hot carriers in nano-graphite film." Applied Physics Letters 121, no. 18 (October 31, 2022): 181104. http://dx.doi.org/10.1063/5.0116720.

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Charge carrier scattering channels in graphite bridging its valence and conduction band offer an efficient Auger recombination dynamic to promote low energy charge carriers to higher energy states. It is of importance to answer the question whether a large number of charge carriers can be promoted to higher energy states to enhance the quantum efficiency of photodetectors. Here, we present an experimental demonstration of an effective Auger recombination process in the photo-excited nano-graphite film. The time-resolved hot carrier thermalization was analyzed based on the energy dissipation via the Auger scattering channels. We split the Auger recombination occurrence centered at 0.40 eV energy state into scattering and recombination parts, for characterizing the scattering rate in the conduction band and the recombination rate toward the valence band. The scattering time with respect to the energy state was extracted as 8 ps · eV−1, while the recombination time with respect to the energy state was extracted as 24 ps · eV−1. Our study indicates a 300 fs delay between the hot carrier recombination and generation, leading to a 105 ps−1 · cm−3 Auger scattering efficiency. The observed duration for the Auger recombination to generate hot carriers is prolonged for 1 ps, due to the hot carriers energy relaxation bottleneck with optical-phonons in the nano-graphite. The presented analytic expression gives valuable insights into the Auger recombination dynamic to estimate its most efficient energy regime for mid-infrared photodetection.
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KUZEMSKY, A. L. "BOUND AND SCATTERING STATES OF ITINERANT CHARGE CARRIERS IN COMPLEX MAGNETIC MATERIALS." International Journal of Modern Physics B 18, no. 23n24 (October 10, 2004): 3227–66. http://dx.doi.org/10.1142/s0217979204026391.

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The concept of magnetic polaron is analyzed and developed to elucidate the nature of itinerant charge carrier states in magnetic semiconductors and similar complex magnetic materials. By contrasting the scattering and bound states of carriers within the s–d exchange model, the nature of bound states at finite temperatures is clarified. The free magnetic polaron at certain conditions is realized as a bound state of the carrier (electron or hole) with the spin wave. Quite generally, a self-consistent theory of a magnetic polaron is formulated within a nonperturbative many-body approach, the Irreducible Green Functions (IGF) method which is used to describe the quasiparticle many-body dynamics at finite temperatures. Within the above many-body approach we elaborate a self-consistent picture of dynamic behavior of two interacting subsystems, the localized spins and the itinerant charge carriers. In particular, we show that the relevant generalized mean fields emerges naturally within our formalism. At the same time, the correct separation of elastic scattering corrections permits one to consider the damping effects (inelastic scattering corrections) in the unified and coherent fashion. The damping of magnetic polaron state, which is quite different from the damping of the scattering states, finds a natural interpretation within the present self-consistent scheme.
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Frolov, I. V., O. A. Radaev, and V. A. Sergeev. "Investigation of the dynamic parameters of electroluminescence in different parts of the spectrum in local regions of the light-emitting heterostructure." Journal of Physics: Conference Series 2086, no. 1 (December 1, 2021): 012083. http://dx.doi.org/10.1088/1742-6596/2086/1/012083.

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Abstract A method for measuring the distribution of the differential charge carriers lifetime over energy levels in the local regions of a light-emitting heterostructure is presented. The method has been tested on commercial green InGaN-based LEDs. It has been determined that with an increase in the energy level (with decreasing wavelength), the charge carriers lifetime decreases. It is shown that the relative inhomogeneity of the distribution of the charge carriers lifetimes in local regions of the die in the long-wavelength part of the electroluminescence spectrum is higher than in the short-wavelength part of the spectrum.
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Uratani, Hiroki. "(Invited) Simulating Dynamic Excitons Via Quantum Molecular Dynamics: A Case Study in Lead Halide Perovskites." ECS Meeting Abstracts MA2022-01, no. 13 (July 7, 2022): 904. http://dx.doi.org/10.1149/ma2022-0113904mtgabs.

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The ultrafast electronic and structural dynamics invoked by photoexcitation, i.e., “dynamic exciton” phenomena, not only are important in the context of practical applications such as solar cells, but also raise many questions from the viewpoint of fundamental science. Experimental measurement, computational simulations, and theoretical interpretation will be the three pillars for deciphering the dynamic exciton phenomena. From the viewpoint of computational simulations, molecular dynamics (MD) techniques combined with quantum chemical calculations, i.e., quantum molecular dynamics (QMD), has been the popular tool to simulate the dynamic exciton phenomena. The quantum chemical calculations, which are typically conducted on the basis of the density-functional theory (DFT), require the large computational resources and time. These have been the limiting factors for the accessible spatial and time scales by the QMD simulations. To extend the coverage of simulations to more complex, large-scale systems, we have developed efficient excited-state QMD methods that can include nonadiabatic effects. Our method combines the density-functional tight binding (DFTB) method, which is an approximate DFT, and the surface hopping method, which is a theoretical framework to incorporate the nonadiabatic effects into the QMD simulations. The method was further improved to be suitable for condensed-phase simulations explicitly including the environment, i.e., solvent, by using a “divide-and-conquer” style quantum chemical calculation technique. These theoretical framework enables us to simulate the coupled electronic–structural dynamics in excited states of systems consisting of 102–103 atoms[1,2,3]. In addition, using the developed method, we conducted the real-time simulations of the ultrafast processes invoked by photoexcitation of lead iodide perovskites, which are known as the key materials for perovskite solar cells. The dissociation of the exciton into the positive and negative charge carriers was observed. Moreover, the hot carrier cooling, where the charge carriers dissipate excess energy via the electron–phonon coupling and relax to the band edges, was also tracked. Finally, the direct evidence of the polaron formation, where the structural deformation is induced by the presence of charge carriers, was observed. These results highlight the importance of the coupling between electronic and structural degrees of freedom. In the talk, recent improvements in the methodology and future perspectives will also be presented[5]. References [1] H. Uratani and H. Nakai, J. Chem. Phys. 152, 224109 (2020). [2] H. Uratani, T. Morioka, T. Yoshikawa, and H. Nakai, J. Chem. Theory Comput. 16, 7299 (2020). [3] H. Uratani, T. Yoshikawa, and H. Nakai, J. Chem. Theory Comput. 17, 1290 (2021). [4] H. Uratani and H. Nakai, J. Phys. Chem. Lett. 11, 4448 (2020). [5] H. Uratani and H. Nakai, J. Chem. Theory Comput. in press. Figure 1
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Kim, Sun-Kyo, and Yong-Seog Kim. "Charge carrier injection and transport in QLED layer with dynamic equilibrium of trapping/de-trapping carriers." Journal of Applied Physics 126, no. 3 (July 21, 2019): 035704. http://dx.doi.org/10.1063/1.5109089.

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Pfeiffer, Carl. "Semiconductor 1/f noise from dynamic coupling of charge carriers and lattice." Journal of Applied Physics 90, no. 7 (October 2001): 3653–55. http://dx.doi.org/10.1063/1.1388020.

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BRYKSIN, V. V., and P. KLEINERT. "DYNAMIC MAGNETOELECTRIC AND CHARGE-HALL EFFECTS IN THE RASHBA–DRESSELHAUS MODEL." International Journal of Modern Physics B 20, no. 29 (November 20, 2006): 4937–46. http://dx.doi.org/10.1142/s0217979206035680.

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In a biased two-dimensional electron gas, the presence of spin-orbit coupling of both the Rashba and Dresselhaus type leads to a Hall conductivity of charge carriers in the absence of an external magnetic field. We study the dynamical charge-Hall effect, the field-induced spin accumulation, and the magnetoelectric effect for a system with short-range elastic impurity scattering by analytically solving the kinetic equations for the spin-density matrix in the linear response regime. By tuning the strength of the Rashba and Dresselhaus spin-orbit coupling as well as the frequency and direction of the applied electric field, eigenmodes of the spin-coupled system are identified.
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Dissertations / Theses on the topic "Charge carriers dynamic"

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Grigioni, I. "DEVELOPMENT OF PHOTOCATALYTIC MATERIALS FOR SOLAR LIGHT CONVERSION INTO FUELS." Doctoral thesis, Università degli Studi di Milano, 2015. http://hdl.handle.net/2434/333066.

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Solar light possesses a large amount of energy. The sun provides to our planet an intense flux of high energetic photons capable to promote extremely up-hill reactions, such as the photosynthetic fixation of CO2 in biological systems. This energy flow drives life on Earth. My PhD thesis is focused on solar driven conversion processes. While in the first year I principally investigated the photocatalytic reduction of CO2 with TiO2-based materials. In the second year I started to explore new promising visible light harvesting materials and in particular I worked on CdSe quantum dots synthesis and on their use as photocatalysts for hydrogen production under visible light, with special interest on the size dependent recombination of the photogenerated. Finally, during my stage by Professor Kamat’s laboratory at Notre Dame University (Indiana, US), I started to work on the use of WO3/BiVO4 heterojunction photoanodes, for photoelectrocatalytic applications, and especially on charge carriers dynamics through transient absorption spectroscopy measurements. A short overview of the main themes treated during my PhD is outlined below. 1st year 1. Photocatalytic tests on TiO2 based materials in the photoassisted reactions of CO2 reduction and steam reforming of methanol, as a part of the research project FotoRiduCO2 PON01_02257. 2nd year 2. Synthesis and characterization of CdSe quantum dots with different size and their application in photocatalytic H2 production under visible light irradiation. 3. Preparation of WO3, BiVO4 and WO3/BiVO4 photoanodes for photoelectrochemical water splitting application and their study with transient absorption techniques. 3rd year 4. Preparation and characterization through femtosecond transient absorption spectroscopy of BiVO4 and WO3/BiVO4 films with variable BiVO4 thickness. The use of different pump energy allowed to suggest a new optical transition model that accounts for the electron transfer paths between the two oxides. Photoelectrochemical experiments validate the proposed model.
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Böhme, Christoph. "Dynamics of spin-dependent charge carrier recombination." [S.l.] : [s.n.], 2003. http://archiv.ub.uni-marburg.de/diss/z2003/0183.

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Yamamoto, Shunsuke. "Charge Carrier Dynamics in Polymer Solar Cells." 京都大学 (Kyoto University), 2012. http://hdl.handle.net/2433/157616.

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Solowan, Hans-Michael [Verfasser], and Ulrich T. [Akademischer Betreuer] Schwarz. "Charge carrier dynamics in InGaN quantum wells: stimulated emission depletion and lateral charge carrier motion." Freiburg : Universität, 2016. http://d-nb.info/1119452694/34.

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D'Souza, Arvind Inacib. "Picosecond dynamics of charged carriers in amorphous semiconductors /." The Ohio State University, 1985. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487260135357755.

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Lambright, Scott. "Ultrafast Charge Carrier Dynamics in Au/Semiconductor Nanoheterostructures." Bowling Green State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1404741549.

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Rueda, Delgado Diana Paola. "Charge carrier dynamics and interfaces in perovskite solar cells." Doctoral thesis, Universitat Politècnica de Catalunya, 2019. http://hdl.handle.net/10803/667466.

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Organometal halide perovskites for solar cells are hybrid semiconductors that recently have caught the attention of the scientific community due to its excellent performance and attractive optical properties. Since then, they have been used in solar cells, LEDs, and lasers, although the mechanisms by which such good performances are obtained are not known completely. This dissertation presents a study of the optical characteristics of perovskites for thin-film solar cells. Due to their small thickness, the morphology of the layer is sensitive to manufacturing parameters. In this way, the manufacturing process is optimized, trying to improve its characteristics. Among the challenges perovskites pose for implementation, the lack of stability during operation is one of the most relevant. Therefore, in this dissertation, the reasons for stability losses are also studied. For this purpose, interlayers are used, which introduce changes in the interface of the perovskite with the electron extraction layer, and with the initial purpose of reducing the hysteresis in the current-voltage curve. In addition to reducing it, they stabilize the power extracted from the solar cell under illumination. The effects of degradation on the characteristics of solar cells allow the identification of their origins and propose a solution to avoid or delay damage to the perovskite layer. With this in mind, it is established that the problem of stability does not only lie within the perovskite layer but also in the contact between the layers and in the charge transport within the perovskite solar cell. Careful control of these interfaces, then, facilitates the achievement of stable performances and long lifetimes of the perovskite solar cells.
Las perovskitas organometálicas de haluros para celdas solares son un tipo de semiconductor híbrido que recientemente ha atrapado la atención de la comunidad científica debido a su excelente desempeño y atractivas propiedades ópticas. Desde entonces, han sido utilizadas en celdas solares, LEDs y lasers, a pesar de que los mecanismos por los cuales se obtienen tan buenos desempeños no son completamente conocidos. Con esta disertación se presenta un estudio sobre las características ópticas de la perovskitas para su utilización en celdas solares de películas delgadas. Debido a su delgado grosor, la morfología de la capa es sensible a los parámetros de fabricación. De manera que se optimiza el proceso de fabricación tratando de mejorar sus características. Entre los retos que presentan las perosvkitas para su implementación, la falta de estabilidad durante su funcionamiento es uno de los más relevantes. Entonces en este dissertationo se estudian también las razones por las que se presenta pérdidas de estabilidad. Para esto se utilizan entrecapas, que introducen cambios en la interfaz de la perovksite con la capa extractora de electrones, y con el propósito inicial de reducir la histéresis en la curva de corriente-voltaje. Además de reducirlo, estabilizan la potencia extraída de la celda solar bajo iluminación. Los efectos de la degradación en las características de las celdas solares nos permiten identificar sus orígenes y presentar propuestas para evitar o retardar los daños a la capa de perovskita. Teniendo esto en cuenta, podemos establecer que el problema de la estabilidad no radica sólo dentro de la perovskita, pero también en el contacto entre las capas y en el transporte de carga dentro de la celda solar de perovskita. El control cuidadoso de estas interfaces, entonces, permite la obtención de un rendimiento estable y una vida larga del dispositivo.
Organometallhalogenid-Perowskite sind hybride Halbleiter, die in jüngster Zeit aufgrund ihrer hervorragenden Halbleitereingeschaften und attraktiven optischen Eigenschaften die Aufmerksamkeit der Wissenschaft auf sich gezogen haben. Seitdem wurde die exzellente Eignung dieser Materialklasse für verschiedenste opto-elektrische Anwendungen wie z.B. Solarzellen, LEDs und Lasern unter Beweis gestellt. Die physikalischen Mechanismen, die die Grundlage für diese einzigartigen, qualitativ Hochwertigen Eigenschaften bilden, sind jedoch noch weitgehend unbekannt. Dieses Manuskript stellt eine Studie über die optischen Eigenschaften von Perowskitfilmen für den Einsatz in Dünnschichtsolarzellen dar, die mit dem Spin-Coating-Verfahren hergestellt wurden. Aufgrund des geringen Dicken der Perowskitschichten ist deren Morphologie empfindlich gegenüber kleinen Variationen der Fertigungsparameter. Deshalb muss der Herstellungsprozess durch Feinjustierung dieser Parameter optimiert werden, um hocheffiziente Solarzellen herzustellen. Eine der größten Herausforderungen für die Kommerzialisierung der Perowskitphotovoltaik ist neben der Herstellung durch die mangelnde Stabilität des Wirkungsgerades während des Betriebs gegeben. Daher werden in der vorliegenden Arbeit zusätzlich die Gründe für diese Stabilitätsverluste untersucht. Zu diesem Zweck werden zusätzliche Nanoschichten zwischen der Perowskit- und der Elektronenextraktionsschicht appliziert, die nicht nur eine Reduzierung der Hysterese in der Strom-Spannungskurve bewirken, sondern die Leistung der Solarzelle unter Sonneneinstrahlung stabilisieren. Der Vergleich der Stabilität von Solarzellen mit und ohne zusätzlichen Zwischenschichten ermöglicht Rückschlüsse auf die Ursache der Degradationsmechanismen. Ein Hauptresultat dieser Stabilitäts- bzw. Degradationsstudie ist die Tatsache, dass ein Großteil des beobachteten Effizienzverlustes nicht durch die Perowskitdegradation innerhalb des Filmes, sondern vielmehr durch die Instabilität der Grenzflächen des Perowskits mit den Extraktionsschichten zustande kommt. Die Grenzflächendegradation erzeugt eine Barriere für den Ladungstransport durch die Erhöhung der lokalen „Trap-Dichte“. Basierend auf dieser Erkenntnis eröffnet die sorgfältige Modifikation der Grenzflächen innerhalb der Solarzelle vielfältige Möglichkeiten, um eine stabile Betriebsleistung der Solarzelle über längere Zeiten durch Vermeidung bzw. Verzögerung der Degradation zu erzielen
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Gilmore, Rachel Hoffman. "Charge carrier dynamics in lead sulfide quantum dot solids." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/115015.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemical Engineering, September 2017.
Cataloged from PDF version of thesis. "February 2018." Handwritten on title page: [September 2017].
Includes bibliographical references (pages 105-117).
Quantum dots, also called semiconductor nanocrystals, are an interesting class of materials because their band gap is a function of the quantum dot size. Their optical properties are not determined solely by the atomic composition, but may be engineered. Advances in quantum dot synthesis have enabled control of the ensemble size dispersity and the creation of monodisperse quantum dot ensembles with size variations of less than one atomic layer. Quantum dots have been used in a variety of applications including solar cells, light-emitting diodes, photodetectors, and thermoelectrics. In many of these applications, understanding charge transport in quantum dot solids is crucial to optimizing efficient devices. We examine charge transport in monodisperse, coupled quantum dot solids using spectroscopic techniques explained by hopping transport models that provide a complementary picture to device measurements. In our monodisperse quantum dot solids, the site-to-site energetic disorder that comes from size dispersity and the size-dependent band gap is very small and spatial disorder in the quantum dot superlattice often has a greater impact on charge transport. In Chapter 2, we show that improved structural order from self-assembly in monodisperse quantum dots reduces the interparticle spacing and has a greater impact than reduced energetic disorder on increasing charge carrier hopping rates. In Chapter 3, we present temperature-dependent transport measurements that demonstrate again that when energetic disorder is very low, structural changes will dominate the dynamics. We find increasing mobility with decreasing temperature that can be explained by a 1-2 Å contraction in the edge-to-edge nearest neighbor quantum dot spacing. In Chapter 4, we study optical states that are 100-200 meV lower in energy than the band gap. Because we work with monodisperse quantum dots, we are able to resolve this trap state separately from the band edge state and study its optical properties. We identify the trap state as dimers that form during synthesis and ligand exchange when two bare quantum dot surfaces fuse. The findings of this thesis point to the importance of minimizing the structural disorder of the coupled quantum dot solid in addition to the energetic disorder to optimize charge carrier transport.
by Rachel Hoffman Gilmore.
Ph. D.
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Peckus, Domantas. "Ultrafast exciton and charge carrier dynamics in nanostructured molecular layers." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2013~D_20131220_150447-81409.

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Due to their unique properties organic semiconductors may be used for various applications in organic optoelectronic devices: light emitting devices, lasers, field-effect transistors, photovoltaic cells and etc. Despite high perspectives of organic semiconductors they are still upstaged by their inorganic counterparts. Development of organic electronics requires better understanding of electrooptical properties of organic semiconductors and relationships between their structure and functions. The main goal of this thesis is a detailed investigation of ultrafast exciton and charge carrier processes in pure organic semiconductors and their blends with fullerene derivatives. Investigated organic or silicon organic semiconductors were poly-di-n-hexylsilane (PDHS), polyfluorenes F8BT and PSF-BT, merocyanine MD376. C60 fullerene and its derivative PCBM were used in blends. Ultrafast transient absorption, fluorescence, and integral mode photocurrent measurements were used for investigations. The investigation of PDHS nanocomposites revealed that PDHS incorporation into nanopores can be used for improvement of fluorescence properties. Formation of intramolecular charge transfer state was proposed for PSF-BT neat films. Charge transfer scheme of the formation of long-lived charge pair state in PSF-BT/PCBM blend was presented. The charge pair and free charge carrier generation scheme in merocyanine blends with fullerene derivatives were discussed in detail. Analysis of measurement... [to full text]
Dėl savo unikalių savybių organiniai puslaidininkiai gali būti plačiai pritaikyti įvairiuose optoelektroniniuose prietaisuose: organiniuose šviestukuose, organiniuose lazeriuose, organiniuose tranzistoriuose ir organiniuose šviesos elementuose. Visi šie pritaikymai yra galimi dėl organinių molekulių laidumo. Nepaisant didelių organinių puslaidininkių perspektyvų, jie vis dar yra nukonkuruojami neorganinių puslaidininkių. Pagrindinis šių tezių tikslas yra detaliai ištirti eksitonų ir krūvininkų dinamikos procesus grynuose organiniuose puslaidininkiuose ir jų mišiniuose su fulereno dariniais. Buvo matuoti organiniai ir silicio organiniai puslaidininkiai: poli-di-n-heksilsilanas (PDHS), polifluoreno dariniai F8BT ir PSF-BT, merocianinas MD376. Mišiniuose naudoti fulerenai buvo C60 ir jo darinys PCBM. Tyrimams buvo naudoti ultraspartūs skirtuminės sugerties, fluorescencijos ir integralinės fotosrovės matavimai. PDHS tyrimai atskleidė, kad neorganinės matricos sumažina nespindulinį relaksacijos kanalą. PDHS nanokompozitai gali būti naudojami polimero fluorescencijos savybių: stabilumo, kvantinio našumo pagerinimui. Polifluorenų F8BT ir PSF-BT grynų plėvelių tyrimų metu nustatyti eksitonų-eksitonų anihiliacijos ir eksitonų migracijos skirtumai. Vidumolekulinės krūvio pernašos būsenos formavimasis buvo pasiūlytas PSF-BT grynoms plėvelėms. Pristatyta ilgi gyvuojančių krūvininkų porų formavimosi schema PSF-BT/PCBM mišiniuose. Krūvio pernašos būsenų formavimasis buvo ištirtas... [toliau žr. visą tekstą]
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Strothkämper, Christian [Verfasser]. "Charge Carrier Dynamics in Thin Film Solar Cells / Christian Strothkämper." Berlin : Freie Universität Berlin, 2013. http://d-nb.info/1037725832/34.

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Books on the topic "Charge carriers dynamic"

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Perednya, Dmitriy, Aleksandr Belyaev, and Oleg Filimonov. Dynamic aspects of the managerial culture of the internal affairs bodies of Russia. ru: INFRA-M Academic Publishing LLC., 2022. http://dx.doi.org/10.12737/1872859.

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In the monograph, the focus of research interest is primarily focused on the dynamic aspects of the managerial culture of the internal affairs bodies. The understanding of the object-subject area was carried out based on empirical data accumulated in recent years concerning changes in the managerial culture of internal affairs bodies. At all times, management has been important for social structures. The fact is that the effective functioning of the organization is based on reasons directly or indirectly related to management issues, the form of existence of which is managerial culture. It is a complex phenomenon that is relevant both in research and in applied terms. For a wide range of readers interested in the issues of managerial culture of internal affairs bodies. It can be useful for students, postgraduates and teachers of law schools.
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Gruzdev, Vladimir, Sergey Suslov, Vladimir Kosinskiy, and Mariya Hrustaleva. Changes in the composition and structure of the components of the landscapes of the forest zone in the conditions of technogenesis. ru: INFRA-M Academic Publishing LLC., 2023. http://dx.doi.org/10.12737/1850657.

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The monograph is devoted to the analysis of changes in the structure of natural and agricultural landscapes under conditions of anthropogenic, including man-made, impact on landscapes. The author summarizes his own research conducted in the forest zone in the subzones of the middle and southern taiga and broad-leaved coniferous forests. The studies were carried out in forests, meadows and swamps, and also studied the formation of the quality of natural waters and the overgrowth of reservoirs in the forest zone. The composition and structure of zonal plant communities and the dynamic successional stages of secondary, derived communities formed in logging, burning, flooding by reservoirs, man-made pollution, as well as integrated anthropogenic impact are considered. Factors of technogenic transformation of landscapes are analyzed. The analysis of the complex of anthropogenic impacts has been carried out and the main trends of anthropogenic dynamics of soil and vegetation cover have been identified, recommendations for optimization and rationalization of nature management under anthropogenic impact are given. The issues of formation of geotechnical systems, their structure and issues of interaction in the system "man and nature" are considered. It is of interest to ecologists, geographers, biologists. It can be used in the work of state bodies for monitoring the state of the environment and in the educational process — by teachers and students dealing with ecology, nature management, biology, environmental monitoring, territory engineering, as well as by researchers, graduate students and applicants.
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Borzyh, Stanislav. Urban evolution. ru: INFRA-M Academic Publishing LLC., 2022. http://dx.doi.org/10.12737/1841828.

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The monograph is devoted to evolution, but in the form that man gave it. It is assumed that unnatural conditions of its flow were created in cities and near them, which changed the logic of its functioning, but this has become especially noticeable over the past hundred years, during which the entire planet was included in the orbit of our influence. This made it possible to unite the Earth into one whole, but at the same time it transformed the work of natural selection, turning it into an artificial one that concerns everyone and everything, without any exceptions. Accordingly, three planes of its unfolding are considered, namely: geography, the biosphere and our species, in each of which the same dynamics of its implementation can be traced. From all this, it is concluded that today there is no wild and inherent in the whole history of his version, but the one that prevails is that we, consciously and not, planted on this space object with all its inhabitants. This new version of it is proposed to be called urban revolution - by the name of the site of its unfolding and everything that is associated with it, but it is repeatedly emphasized that the essence of the process has remained the same, the scene where it is carried out has simply been transformed. It is intended for both specialists and the general public.
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Barbera, Filippo, Roberto Paladini, and Marco Vedovato. Venice Original E-commerce dell’artigianato artistico e tradizionale veneziano. Venice: Fondazione Università Ca’ Foscari, 2022. http://dx.doi.org/10.30687/978-88-6969-615-2.

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In the last few years, many researchers have highlighted the economic and cultural impact that crafts have on the development of territories, enhancing local identities and traditions. Various researches also point to the close relationship between trade (sometimes called ‘neighbourhood’ trade), crafts and historic centres, in terms of quality of life, and socio-economic and identity development of territories, showing their new centrality to processes of urban development and regeneration and the formation of social capital. It is evident how enterprise contributes to local development through social interactions based on negotiated and open collaborations between microenterprises, community and network. It was well argued how small business (commerce, crafts and neighbourhood stores) has always played an important role as a social garrison in sparsely populated areas, allowing cities and particularly urban centres to become more lively or livable, being able to give or take away quality from the city and the territory, attributing peculiarity, security and specificity to places or trivialising them in a homogenised landscape. Among the services of social utility recognised to the artisan workshop are: the guarantee of services useful to the livability of the place, the garrisoning of territories and the development of social relations, the promotion of local identity and its know-how, and the creation of employment opportunities through modest initial availability of capital. At the same time, the worsening recessionary dynamics that have occurred in the global economy over the past two decades and the disruptive digital transition have exposed such enterprises to increasing difficulties, disruptively accentuating the decline in competitiveness and propensity to innovate of a large proportion of craft SMEs, of which the socioeconomic literature does not see significant adaptations to the changed environment, such as reconfiguring the business model, adopting a totally new strategic plan adapting to the digital transition, generational transition, and adopting innovative organisational or system behaviours. This volume presents the Venice Original E-Commerce case – a project carried out by the Venice Metropolitan CNA thanks to the support of J.P. Morgan, the support of the Venice Rovigo Chamber of Commerce and the sponsorship of the City of Venice and Ca’ Foscari University of Venice – as a reference project intervention to focus on a possible model of intervention to support culturally-valued artisan micro-enterprises, intervening on the process of strategic renewal and the conditions to foster generational turnover, understood as an opportunity to fill the gap on the digitisation of the artisan sector.
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Shuford, Kevin L. Quantum control of charge carrier dynamics in layered semiconductor heterostructures. 2003.

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Dicker, Gerald. Photogeneration & Dynamics of Charge Carriers in the Conjugated Polymer Poly (3-hexylthiophene). Delft Univ Pr, 2004.

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Ponseca, Carlito S. Chapter 11 Charge Carrier Dynamics in Organometal Halide Perovskite Probed by Time-Resolved Electrical Measurements. InTechOpen, 2016.

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Glazov, M. M. Electron & Nuclear Spin Dynamics in Semiconductor Nanostructures. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198807308.001.0001.

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In recent years, the physics community has experienced a revival of interest in spin effects in solid state systems. On one hand, solid state systems, particularly semicon- ductors and semiconductor nanosystems, allow one to perform benchtop studies of quantum and relativistic phenomena. On the other hand, interest is supported by the prospects of realizing spin-based electronics where the electron or nuclear spins can play a role of quantum or classical information carriers. This book aims at rather detailed presentation of multifaceted physics of interacting electron and nuclear spins in semiconductors and, particularly, in semiconductor-based low-dimensional structures. The hyperfine interaction of the charge carrier and nuclear spins increases in nanosystems compared with bulk materials due to localization of electrons and holes and results in the spin exchange between these two systems. It gives rise to beautiful and complex physics occurring in the manybody and nonlinear system of electrons and nuclei in semiconductor nanosystems. As a result, an understanding of the intertwined spin systems of electrons and nuclei is crucial for in-depth studying and control of spin phenomena in semiconductors. The book addresses a number of the most prominent effects taking place in semiconductor nanosystems including hyperfine interaction, nuclear magnetic resonance, dynamical nuclear polarization, spin-Faraday and -Kerr effects, processes of electron spin decoherence and relaxation, effects of electron spin precession mode-locking and frequency focusing, as well as fluctuations of electron and nuclear spins.
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Glazov, M. M. Electron Spin Precession Mode Locking and Nuclei-Induced Frequency Focusing. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198807308.003.0009.

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This chapter addresses a rich variety of effects in spin dynamics arising under the conditions of pump-probe experiments. Here we consider the case where the electron spin is injected by a periodic train of circularly polarized pump pulses and precesses between the pulses in an external magnetic field. Nontrivial effects such as resonant spin amplification and spin coherence mode-locking take place due to commensurability of the repetition period of pump pulses and the charge carrier spin precession period. Theoretical approaches to describing the electron and nuclear spin coherence and experimental manifestations of these unusual regimes of spin dynamics are discussed in detail.
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Glazov, M. M. Strong Coupling of Electron and Nuclear Spins: Outlook and Prospects. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198807308.003.0011.

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In this chapter, some prospects in the field of electron and nuclear spin dynamics are outlined. Particular emphasis is put ona situation where the hyperfine interaction is so strong that it leads to a qualitative rearrangement of the energy spectrum resulting in the coherent excitation transfer between the electron and nucleus. The strong coupling between the spin of the charge carrier and of the nucleus is realized, for example in the case of deep impurity centers in semiconductors or in isotopically purified systems. We also discuss the effect of the nuclear spin polaron, that is ordered state, formation at low enough temperatures of nuclear spins, where the orientation of the carrier spin results in alignment of the spins of nucleus interacting with the electron or hole.
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Book chapters on the topic "Charge carriers dynamic"

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Giesecke, Johannes. "Dynamics of Charge Carriers." In Springer Theses, 25–63. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-06157-3_3.

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Scheibenzuber, Wolfgang G. "Dynamics of Charge Carriers and Photons." In GaN-Based Laser Diodes, 55–66. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-24538-1_6.

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Ravaioli, U., T. A. van der Straaten, and G. Kathawala. "Implicit Water Simulations of Non-Equilibrium Charge Transport in Ion Channels." In Nonequilibrium Carrier Dynamics in Semiconductors, 205–9. Berlin, Heidelberg: Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/978-3-540-36588-4_46.

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Ohkita, Hideo. "Charge Carrier Dynamics in Polymer Solar Cells." In Organic Solar Cells, 123–54. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-9113-6_6.

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Pethig, R. "Hopping Charge Carriers in Molecular Crystals and Biopolymers: The Fröhlich Connection." In Energy Transfer Dynamics, 257–63. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-71867-0_25.

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Perfetti, Luca, Tobias Kampfrath, Martin Wolf, and Christian Frischkorn. "Ultrafast Charge-Carrier Dynamics in Low-Dimensional Solids." In Ultrafast Phenomena XV, 612–14. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-68781-8_197.

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Mizoguchi, Kenji. "Microscopic and Anisotropic Dynamics of Spin Carriers with/without Charge." In Springer Proceedings in Physics, 70–84. Tokyo: Springer Japan, 1996. http://dx.doi.org/10.1007/978-4-431-68470-1_6.

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Noguchi, Yutaka, Yuya Tanaka, Yukimasa Miyazaki, Naoki Sato, Yasuo Nakayama, and Hisao Ishii. "Displacement Current Measurement for Exploring Charge Carrier Dynamics in Organic Semiconductor Devices." In Physics of Organic Semiconductors, 119–54. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2013. http://dx.doi.org/10.1002/9783527654949.ch5.

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Akimov, Alexey V., and Oleg V. Prezhdo. "Nonradiative Relaxation of Charge Carriers in GaN-InN Alloys: Insights from Nonadiabatic Molecular Dynamics." In Photoinduced Processes at Surfaces and in Nanomaterials, 189–200. Washington, DC: American Chemical Society, 2015. http://dx.doi.org/10.1021/bk-2015-1196.ch009.

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Chang, Kiseok, Ryan A. Murdick, Tzong-Ru T. Han, Fei Yuan, and Chong-Yu Ruan. "Light-Induced Charge Carrier Dynamics at Nanostructured Interfaces Investigated by Ultrafast Electron Diffractive Photovoltammetry." In Lecture Notes in Nanoscale Science and Technology, 311–47. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-8148-5_13.

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Conference papers on the topic "Charge carriers dynamic"

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Barone, C., F. Romeo, and S. Pagano. "Dynamic behaviors of the charge carriers investigated by means of noise spectroscopy." In 2013 International Conference on Noise and Fluctuations (ICNF). IEEE, 2013. http://dx.doi.org/10.1109/icnf.2013.6578882.

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Tataronis, J. A., George C. Papen, and B. E. A. Saleh. "Transient optical phase conjugation in dynamic media." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/oam.1987.mf14.

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We explore dynamic media, such as plasmas and photorefractive materials, as generators of phase conjugated replicas of transient optical signals via four-wave mixing. The characterizing element of dynamic media is a population of free charge carriers that leads to induced charge density gratings on probe illumination. In steady-state conditions, phase conjugation in such media normally appears with smaller pump intensities than are required in Kerr media but at the expense of potentially slow response times.1
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Hutchings, D. C., C. B. Park, and A. Miller. "Modeling of cross–well carrier transport in a multiple quantum well pin structure." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/oam.1991.mff2.

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We have previously measured the photoconductive response in a GaAs/AlGaAs multiple quantum well (MQW) pin diode on picosecond timescales by the excite-probe technique.1 These results give information on the fundamental operating limits of the quantum-well self electrooptic effect device (SEED) and MQW photodetectors. The rise time of the transient transmission change generally decreased as a function of reverse bias voltage with a pronounced minimum (30 ps) at a voltage level corresponding to resonant electron tunneling. A numerical algorithm has been developed to model this transient response. The electric field dependent time constants for the various carrier dynamic processes are determined first, such as escape of carriers from the wells by tunneling or thermionic emission, drift of carriers in the field, and recapture of carriers into the wells. The temporal and spatial evolution of the photoexcited electron and hole populations are then calculated self-consistently by including the space-charge contributions to the local electric field throughout the structure. The decay of the transmission change is included by allowing transverse diffusion of the excitation in the n-doped contact region. We also include the effects of a nonuniform applied field due to impurities. We obtain good agreement with experiment and are thus able to understand the nature of the cross-well transport.
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Alley, Thomas G., Richard A. Myers, and S. R. J. Brueck. "An Ion Exchange Model for Extended-Duration Thermal Poling of Bulk Fused Silica." In Bragg Gratings, Photosensitivity, and Poling in Glass Fibers and Waveguides. Washington, D.C.: Optica Publishing Group, 1997. http://dx.doi.org/10.1364/bgppf.1997.btuc.2.

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Thermal poling induces a strong second-order nonlinearity in bulk fused silica.1 The non-linearity occurs on the anode side of the poled glass; various measurements have shown that the nonlinear region is ~ 5 to 15 μm thick; and that the nonlinearity scales linearly with the applied poling voltage. The formation of the nonlinearity is a dynamic process involving mobile ionic charge carriers.2 We present experimental observations of additional aspects of this dynamic process along with a model that demonstrates that ion exchange can play a role in the formation of the nonlinearity.
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Kim, Y. H., F. Li, and S. W. Cheong. "Dynamics of charge carriers in cuprates." In International Conference on Science and Technology of Synthetic Metals. IEEE, 1994. http://dx.doi.org/10.1109/stsm.1994.836135.

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Sooriyagoda, Rishmali, Herath P. Piyathilaka, Kevin T. Zawilski, Peter G. Schunemann, and Alan D. Bristow. "Charge Carrier and Lattice Carrier Dynamics from Temperature-Dependent Terahertz Spectroscopy." In Frontiers in Optics. Washington, D.C.: OSA, 2020. http://dx.doi.org/10.1364/fio.2020.fm4c.6.

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Strohmair, Simone, Amrita Dey, Yu Tong, Lakshminarayana Polavarapu, Bernhard J. Bohn, and Jochen Feldmann. "Spin Polarization Dynamics of Free Charge Carriers in CsPbI3 Nanocrystals." In Internet Conference for Quantum Dots. València: Fundació Scito, 2020. http://dx.doi.org/10.29363/nanoge.icqd.2020.016.

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Yadav, Sushma, Ajeet Singh Singh, Sameer Sapra Sapra, and Nadja Bigall. "Surface Dependent Charge Carrier Dynamics in Core/Shell Nanoplatelets." In nanoGe Fall Meeting 2018. València: Fundació Scito, 2018. http://dx.doi.org/10.29363/nanoge.fallmeeting.2018.139.

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Durrant, James. "Charge carrier dynamics in organic and perovskite solar cells." In 3rd International Conference on Perovskite and Organic Photovoltaics and Optoelectronics. València: Fundació Scito, 2018. http://dx.doi.org/10.29363/nanoge.iperop.2019.081.

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Liu, Maning, Mohamed Abodya, Weisi Dai, Tokuhisa Kawawaki, Ai Shimazaki, Ryota Sato, Masaki Saruyama, Toshiharu Teranishi, Atsushi Wakamiya, and Yasuhiro Tachibana. "Photo-Induced Charge Carrier Dynamics of Metal Halide Perovskite." In 2022 29th International Workshop on Active-Matrix Flatpanel Displays and Devices (AM-FPD). IEEE, 2022. http://dx.doi.org/10.23919/am-fpd54920.2022.9851264.

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Reports on the topic "Charge carriers dynamic"

1

Klopf, John. Ultrafast Carrier Dynamics Measured by the Transient Change in the Reflectance of InP and GaAs Film. Office of Scientific and Technical Information (OSTI), October 2005. http://dx.doi.org/10.2172/920104.

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Han, Sung Su. Mean carrier transport properties and charge collection dynamics of single-crystal, natural type IIa diamonds from ion-induced conductivity measurements. Office of Scientific and Technical Information (OSTI), September 1993. http://dx.doi.org/10.2172/10185688.

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Soloviev, Vladimir, Andrii Bielinskyi, and Viktoria Solovieva. Entropy Analysis of Crisis Phenomena for DJIA Index. [б. в.], June 2019. http://dx.doi.org/10.31812/123456789/3179.

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The Dow Jones Industrial Average (DJIA) index for the 125-year-old (since 1896) history has experienced many crises of different nature and, reflecting the dynamics of the world stock market, is an ideal model object for the study of quantitative indicators and precursors of crisis phenomena. In this paper, the classification and periodization of crisis events for the DJIA index have been carried out; crashes and critical events have been highlighted. Based on the modern paradigm of the theory of complexity, a spectrum of entropy indicators and precursors of crisis phenomena have been proposed. The entropy of a complex system is not only a measure of uncertainty (like Shannon's entropy) but also a measure of complexity (like the permutation and Tsallis entropy). The complexity of the system in a crisis changes significantly. This fact can be used as an indicator, and in the case of a proactive change as a precursor of a crisis. Complex systems also have the property of scale invariance, which can be taken into account by calculating the Multiscale entropy. The calculations were carried out within the framework of the sliding window algorithm with the subsequent comparison of the entropy measures of complexity with the dynamics of the DJIA index itself. It is shown that Shannon's entropy is an indicator, and the permutation and Tsallis entropy are the precursors of crisis phenomena to the same extent for both crashes and critical events.
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Carpita, Nicholas C., Ruth Ben-Arie, and Amnon Lers. Pectin Cross-Linking Dynamics and Wall Softening during Fruit Ripening. United States Department of Agriculture, July 2002. http://dx.doi.org/10.32747/2002.7585197.bard.

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Our study was designed to elucidate the chemical determinants of pectin cross-linking in developing fruits of apple and peach and to evaluate the role of breakage cross-linkages in swelling, softening, and cell separation during the ripening. Peaches cell walls soften and swell considerably during the ripening, whereas apples fruit cells maintain wall firmness but cells separate during late stages of ripening. We used a "double-reduction" technique to show that levels of non-methyl esters of polyuronic acid molecules were constant during the development and ripening and decreased only in overripe fruit. In peach, methyl and non-methyl esters increased during the development and decreased markedly during the ripening. Non-methyl ester linkages in both fruit decreased accompanied fruit softening. The identity of the second component of the linkage and its definitive role in the fruit softening remain elusive. In preliminary examination of isolated apples cell walls, we found that phenolic compounds accumulate early in wall development but decrease markedly during ripening. Quantitative texture analysis was used to correlate with changes to wall chemistry from the fresh-picked ripe stage to the stage during storage when the cell separation occurs. Cell wall composition is similar in all cultivars, with arabinose as the principal neutral sugar. Extensive de-branching of these highly branched arabinans pre-stages softening and cell-cell separation during over-ripening of apple. The longer 5-arabinans remain attached to the major pectic polymer rhamnogalacturonan I (RG I) backbone. The degree of RG I branching, as judged from the ratios of 2-Rha:2,4-Rha, also decreases, specially after an extensive arabinan de-branching. Loss of the 4-Rham linkages correlated strongly with the softening of the fruit. Loss of the monomer or polymer linked to the RG I produce directly or indirectly the softening of the fruit. This result will help to understand the fruit softening and to have better control of the textural changes in fruit during the ripening and especially during the storage. 'Wooliness', an undesirable mealy texture that is induced during chilling of some peach cultivars, greatly reduces the fruit storage possibilities. In order to examine the hypothesis that the basis for this disorder is related to abnormality in the cell wall softening process we have carried out a comparative analysis using the resistant cultivar, Sunsnow, and a sensitive one, Hermosa. We investigated the activity of several pectin- and glycan-modifying enzymes and the expression of their genes during ripening, chilling, and subsequent shelf-life. The changes in carbohydrate status and in methyl vs. non-methyl uronate ester levels in the walls of these cultivars were examined as well to provide a basis for comparison of the relevant gene expression that may impact appearance of the wooly character. The activities of the specific polygalacturonase (PGase) and a CMC-cellulase activities are significantly elevated in walls of peaches that have become wooly. Cellulase activities correlated well with increased level of the transcript, but differential expression of PGase did not correspond with the observed pattern of mRNA accumulation. When expression of ethylene biosynthesis related genes was followed no significant differences in ACC synthase gene expression was observed in the wooly fruit while the normal activation of the ACC oxidase was partially repressed in the Hermosa wooly fruits. Normal ripening-related loss of the uronic acid-rich polymers was stalled in the wooly Hermosa inconsistent with the observed elevation in a specific PGase activity but consistent with PG gene expression. In general, analysis of the level of total esterification, degree of methyl esterification and level of non-methyl esters did not reveal any major alterations between the different fruit varieties or between normal and abnormal ripening. Some decrease in the level of uronic acids methyl esterification was observed for both Hermosa and Sunsnow undergoing ripening following storage at low temperature but not in fruits ripening after harvest. Our results support a role for imbalanced cell wall degradation as a basis for the chilling disorder. While these results do not support a role for the imbalance between PG and pectin methyl esterase (PME) activities as the basis for the disorder they suggest a possible role for imbalance between cellulose and other cell wall polymer degradation during the softening process.
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Nechaev, V., Володимир Миколайович Соловйов, and A. Nagibas. Complex economic systems structural organization modelling. Politecnico di Torino, 2006. http://dx.doi.org/10.31812/0564/1118.

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One of the well-known results of the theory of management is the fact, that multi-stage hierarchical organization of management is unstable. Hence, the ideas expressed in a number of works by Don Tapscott on advantages of network organization of businesses over vertically integrated ones is clear. While studying the basic tendencies of business organization in the conditions of globalization, computerization and internetization of the society and the results of the financial activities of the well-known companies, the authors arrive at the conclusion, that such companies, as IBM, Boeing, Mercedes-Benz and some others companies have not been engaged in their traditional business for a long time. Their partner networks performs this function instead of them. The companies themselves perform the function of system integrators. The Tapscott’s idea finds its confirmation within the framework of a new powerful direction of the development of the modern interdisciplinary science – the theory of the complex networks (CN) [2]. CN-s are multifractal objects, the loss of multifractality being the indicator of the system transition from more complex state into more simple state. We tested the multifractal properties of the data using the wavelet transform modulus maxima approach in order to analyze scaling properties of our company. Comparative analysis of the singularity spectrumf(®), namely, the difference between maximum and minimum values of ® (∆ = ®max ¡ ®min) shows that IBM company is considerably more fractal in comparison with Apple Computer. Really, for it the value of ∆ is equal to 0.3, while for the vertically integrated company Apple it only makes 0.06 – 5 times less. The comparison of other companies shows that this dependence is of general character. Taking into consideration the fact that network organization of business has become dominant in the last 5-10 years, we carried out research for the selected companies in the earliest possible period of time which was determined by the availability of data in the Internet, or by historically later beginning of stock trade of computer companies. A singularity spectrum of the first group of companies turned out to be considerably narrower, or shifted toward the smaller values of ® in the pre-network period. The latter means that dynamic series were antipersistant. That is, these companies‘ management was rigidly controlled while the impact of market mechanisms was minimized. In the second group of companies if even the situation did changed it did not change for the better. In addition, we discuss applications to the construction of portfolios of stock that have a stable ratio of risk to return.
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Soloviev, Vladimir, Oleksandr Serdiuk, Serhiy Semerikov, and Arnold Kiv. Recurrence plot-based analysis of financial-economic crashes. [б. в.], October 2020. http://dx.doi.org/10.31812/123456789/4121.

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The article considers the possibility of analyzing the dynamics of changes in the characteristics of time series obtained on the basis of recurrence plots. The possibility of using the studied indicators to determine the presence of critical phenomena in economic systems is considered. Based on the analysis of economic time series of different nature, the suitability of the studied characteristics for the identification of critical phenomena is assessed. The description of recurrence diagrams and characteristics of time series that can be obtained on their basis is given. An analysis of seven characteristics of time series, including the coefficient of self-similarity, the coefficient of predictability, entropy, laminarity, is carried out. For the entropy characteristic, several options for its calculation are considered, each of which allows the one to get its own information about the state of the economic system. The possibility of using the studied characteristics as precursors of critical phenomena in economic systems is analyzed. We have demonstrated that the entropy analysis of financial time series in phase space reveals the characteristic recurrent properties of complex systems. The recurrence entropy methodology has several advantages compared to the traditional recurrence entropy defined in the literature, namely, the correct evaluation of the chaoticity level of the signal, the weak dependence on parameters. The characteristics were studied on the basis of daily values of the Dow Jones index for the period from 1990 to 2019 and daily values of oil prices for the period from 1987 to 2019. The behavior of recurrence entropy during critical phenomena in the stock markets of the USA, Germany and France was studied separately. As a result of the study, it was determined that delay time measure, determinism and laminarity can be used as indicators of critical phenomena. It turned out that recurrence entropy, unlike other entropy indicators of complexity, is an indicator and an early precursor of crisis phenomena. The ways of further research are outlined.
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Belkin, Shimshon, Sylvia Daunert, and Mona Wells. Whole-Cell Biosensor Panel for Agricultural Endocrine Disruptors. United States Department of Agriculture, December 2010. http://dx.doi.org/10.32747/2010.7696542.bard.

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Objectives: The overall objective as defined in the approved proposal was the development of a whole-cell sensor panel for the detection of endocrine disruption activities of agriculturally relevant chemicals. To achieve this goal several specific objectives were outlined: (a) The development of new genetically engineered wholecell sensor strains; (b) the combination of multiple strains into a single sensor panel to effect multiple response modes; (c) development of a computerized algorithm to analyze the panel responses; (d) laboratory testing and calibration; (e) field testing. In the course of the project, mostly due to the change in the US partner, three modifications were introduced to the original objectives: (a) the scope of the project was expanded to include pharmaceuticals (with a focus on antibiotics) in addition to endocrine disrupting chemicals, (b) the computerized algorithm was not fully developed and (c) the field test was not carried out. Background: Chemical agents, such as pesticides applied at inappropriate levels, may compromise water quality or contaminate soils and hence threaten human populations. In recent years, two classes of compounds have been increasingly implicated as emerging risks in agriculturally-related pollution: endocrine disrupting compounds (EDCs) and pharmaceuticals. The latter group may reach the environment by the use of wastewater effluents, whereas many pesticides have been implicated as EDCs. Both groups pose a threat in proportion to their bioavailability, since that which is biounavailable or can be rendered so is a priori not a threat; bioavailability, in turn, is mediated by complex matrices such as soils. Genetically engineered biosensor bacteria hold great promise for sensing bioavailability because the sensor is a live soil- and water-compatible organism with biological response dynamics, and because its response can be genetically “tailored” to report on general toxicity, on bioavailability, and on the presence of specific classes of toxicants. In the present project we have developed a bacterial-based sensor panel incorporating multiple strains of genetically engineered biosensors for the purpose of detecting different types of biological effects. The overall objective as defined in the approved proposal was the development of a whole-cell sensor panel for the detection of endocrine disruption activities of agriculturally relevant chemicals. To achieve this goal several specific objectives were outlined: (a) The development of new genetically engineered wholecell sensor strains; (b) the combination of multiple strains into a single sensor panel to effect multiple response modes; (c) development of a computerized algorithm to analyze the panel responses; (d) laboratory testing and calibration; (e) field testing. In the course of the project, mostly due to the change in the US partner, three modifications were introduced to the original objectives: (a) the scope of the project was expanded to include pharmaceuticals (with a focus on antibiotics) in addition to endocrine disrupting chemicals, (b) the computerized algorithm was not fully developed and (c) the field test was not carried out. Major achievements: (a) construction of innovative bacterial sensor strains for accurate and sensitive detection of agriculturally-relevant pollutants, with a focus on endocrine disrupting compounds (UK and HUJ) and antibiotics (HUJ); (b) optimization of methods for long-term preservation of the reporter bacteria, either by direct deposition on solid surfaces (HUJ) or by the construction of spore-forming Bacillus-based sensors (UK); (c) partial development of a computerized algorithm for the analysis of sensor panel responses. Implications: The sensor panel developed in the course of the project was shown to be applicable for the detection of a broad range of antibiotics and EDCs. Following a suitable development phase, the panel will be ready for testing in an agricultural environment, as an innovative tool for assessing the environmental impacts of EDCs and pharmaceuticals. Furthermore, while the current study relates directly to issues of water quality and soil health, its implications are much broader, with potential uses is risk-based assessment related to the clinical, pharmaceutical, and chemical industries as well as to homeland security.
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