945 resultados para Inelastic collision
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Shot-noise suppression is investigated in nondegenerate diffusive conductors by means of an ensemble Monte Carlo simulator. The universal 1/3 suppression value is obtained when transport occurs under elastic collision regime provided the following conditions are satisfied: (i) The applied voltage is much larger than the thermal value; (ii) the length of the device is much greater than both the elastic mean free path and the Debye length. By fully suppressing carrier-number fluctuations, long-range Coulomb interaction is essential to obtain the 1/3 value in the low-frequency limit.
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Aquest article té dos objectius bàsics. En primer lloc, mostrar la capacitat analítica d'un estudi de cas a l'hora d'estudiar l'expressió de la identitat i dels rols assumits pels participants en la comunicació, posant-la en relació amb els marcs participatius d'Erwing Goffman (1981), d'una banda, i amb la dixi de persona i les seves manifestacions gramaticals (Levinson 1983; Nogué 2008), de l'altra. I en segon lloc, mostrar com l'estructura gramatical pot proporcionar indicadors lingüístics que donen informació sobre la identitat i els rols assumits, posant l'èmfasi en una circumstància concreta: la manera com es reflecteix lingüísticament la col¿lisió entre dos o més rols. Paraules clau: dixi de persona, identitat, rol participatiu, marc participatiu. This article has two main purposes. In the first place, to show how a case study can provide interesting information about the expression of identity and of the different roles assumed by the communication participants. On the one hand, this information is related to the participation frameworks proposed by Erwing Goffman (1981); on the other hand, to person deixis and its grammatical manifestations (Levinson 1983; Nogué 2008). And in the second place, to show how grammatical structure can provide linguistic cues about identity and roles, putting the emphasis on a specific circumstance: the linguistic signs of the collision between two or more of these roles. Key words: person deixis, identity, participation role, participation framework.
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Novel and quantitative mass spectrometry methods for rapid and accurate enantiomeric excess determination are presented. These methodologies use electrospray ionization (ESI) and mass spectrometry (MS) to detect and analyze, via collision-induced dissociation (CID), mass-selected transition metal complexes that promote enantio especific interactions. The data from CID are conveniently treated by the kinetic method, a sensitive linear free energy method of treating mass spectrometric results. Four different variations of this methodology are described: single ratio method (S R), quotient ratio method (Q R), fixed ligand method (S Rfixed), and quotient ratio method with fixed ligand (Q Rfixed). These individual methods are compared and their main features discussed in detail.
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An absolute method is described via mass spectrometry (MS) for the structural assignment of isomers within the class of methylpiperidines. The method explores both the unimolecular and bimolecular gas phase behavior of structurally diagnostic fragment ions (SDFI). For the methylpiperidnes, the isomeric 2-methyl, 3-methyl and 4-methyl 2-azabutadienyl cations are found to function as SDFI. These fragment ions are expected to be formed from all members within the class, to be stable and to retain the structural information of the precursor molecule, and to not interconvert into one another. To characterize these SDFI, both the collision induced dissociation (CID) in argon and bimolecular ion/molecule chemistry with ethyl vinyl ether were compared.
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Potential parameters sensitivity analysis for helium unlike molecules, HeNe, HeAr, HeKr and HeXe is the subject of this work. Number of bound states these rare gas dimers can support, for different angular momentum, will be presented and discussed. The variable phase method, together with the Levinson's theorem, is used to explore the quantum scattering process at very low collision energy using the Tang and Toennies potential. These diatomic dimers can support a bound state even for relative angular momentum equal to five, as in HeXe. Vibrational excited states, with zero angular momentum, are also possible for HeKr and HeXe. Results from sensitive analysis will give acceptable order of magnitude on potentials parameters.
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Potential energy and dipole moment curves for the HCl molecule were computed. Calculations were performed at different levels of theory (DFT, MRCI). Spectroscopic properties are reported and compared with experimental data, for validating the theoretical approaches. Interaction of infrared radiation with HCl is simulated using the wave packet formalism. The quantum control model for population dynamics of the vibrational levels, based on pi-pulse theory, is applied. The results demonstrate that wavepackets with specific composition can be built with short infrared laser pulses and provide the basis for studies of H + HCl collision dynamics with infrared laser excitation.
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Drug trafficking and the introduction of new drugs onto the illicit market are one of the main challenges of the forensic community. In this study, the chemical profile of a new designer drug, 2-(4-iodine-2,5-dimethoxyphenyl)-n-[(2-methoxyphenyl)methyl]etamine or 25I-NBOMe was explored using thin layer chromatography (TLC), ultraviolet-visible spectrophotometry (UV-Vis), attenuated total reflection with Fourier transform infrared spectroscopy(ATR-FTIR), gas chromatography mass spectrometry (GC-MS) and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FT-ICR MS). First, the TLC technique was effective for identifying spots related to 25C-, 25B- and 25I-NBOMe compounds, all with the same retention factor, Rf ≈ 0.50. No spot was detected for 2,5-dimethoxy-4-bromoamphetamine, 2,5-Dimethoxy-4-chloroamphetamine or lysergic acid diethylamide compounds. ATR-FTIR preserved the physical-chemical properties of the material, whereas GC-MS and ESI-MS showed better analytical selectivity. ESI(+)FT-ICR MS was used to identify the exact mass (m/z428.1706 for the [M + H]+ ion), molecular formula (M = C18H22INO3), degree of unsaturation (DBE = 8) and the chemical structure (from collision induced dissociation, CID, experiments) of the 25I-NBOMe compound. Furthermore, the ATR-FTIR and CID results suggested the presence of isomers, where a second structure is proposed as an isomer of the 25I-NBOMe molecule.
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Tässä tutkielmassa korostuu Euroopan sisäinen kulttuurillinen erilaisuus ja sen vaatimukset Suomessa toimiville monikansallisille organisaatioille. Eurooppalaista johtamista on tutkittu jo vuosikymmenten ajan, mutta erityisesti suomalaisesta, Suomessa työskentelevien eurooppalaisten näkökulmasta ei vastaavaa tutkimusta tiettävästi ole aiemmin tehty. Tutkimuksen tavoitteena on selvittää suomalaisen kulttuurin ja johtajuuden arvoeroja muiden Euroopan Unionin maiden kansalaisten näkökulmasta. Pohjois-Euroopan maista tutkimuksessa on mukana edustajia Ruotsista, Tanskasta ja Hollannista. Keski-Euroopan maista edustusta löytyy Saksasta ja Itävallasta, kun Etelä-Eurooppaa edustavat ranskalaiset ja italialaiset henkilöt. Itäisestä Euroopasta mukana on latvialaisia henkilöitä ja anglo-Euroopasta britannialaisia. Tutkimus kartoittaa tutkimukseen mukaan otettujen maiden yhteisö- ja johtamiskulttuurillisia törmäyskohtia suomalaisen kulttuurin kanssa, jotta Suomessa toimivat monikansalliset työyhteisöt löytäisivät yhä parempia strategioita eurooppalaisen ihmispääoman, eurooppalaisten työntekijöiden ja näiden osaamisen, johtamiseksi ja monikansallisen yhteisön toimivuuden ymmärtämiseksi ja parantamiseksi. Näitä törmäyskohtia tarkastellaan empiirisesti Hofsteden (1984) kulttuuridimensioiden, Housen ym. (1999) GLOBE-tutkimuksen ja Koopmanin ym. (1999) johtajuusulottuvuuksien avulla. Tutkimusaineisto koostuu Internet-pohjaisesta kyselystä, joka suoritettiin keväällä 2010. Siihen osallistui 75 Suomessa työskentelevää Euroopan Unionin kansalaista. Analysointimenetelmänä tutkimuksessa käytetään klusterointia, keskiarvoistuksia, Kruskall Wallisin testiä ja sisällönanalyysiä tukemaan määrällisen analyysin tuloksia ja tuomaan esiin siitä poikkeavia havaintoja. Tutkimuksen ytimessä on johtamiskulttuurilliset erot, joista tehdään laajempaa analyysiä edellä mainituin keinoin. Yhteisökulttuurillisia eroja havainnoidaan tutkimuskyselyyn perustuvien väittämien perusteella tehtyjen histogrammien avulla. Tutkimuksen tulokset osoittavat, että maantieteellinen, uskonnollinen tai poliittinen läheisyys eivät määritä kulttuurillista läheisyyttä tai johda kulttuurilliseen sopeutumiseen. Poliittinen raja kahden naapurin välillä saattaa johtaa saman asian kokemiseen kahdella täysin eri tavalla. Lisäksi tuloksista käy ilmi, että yhteisökulttuurilliset ja johtamiskulttuurilliset arvot eivät välttämättä kulje käsikkäin Suomessa työskentelevien eurooppalaisten näkökulmasta. Yleisinä kulttuurillisina kipukohtina tutkimuksessa nousee esiin suomalaisen kulttuurin sosiaalisuuden ja kommunikaation puutteellisuus, toisaalta suomalaiseen kulttuuriin sopeutumista helpottaa suomalainen rehellisyys ja suoruus. Johtamiskulttuurillisina haasteina eurooppalaiset kokevat suomalaisen tyyppijohtajan kyvyttömyyden riskien ottamiseen ja kannustusmenetelmien puutteet. Tämän lisäksi tutkimuksessa tulee ilmi useita tiettyihin kansallisuuksiin liittyviä törmäyskohtia. Tutkimus on nähtävä tämän hetken kuvauksena. Kulttuuritutkimus sisältää monia tekijöitä, jotka ovat jatkuvassa muutoksessa ja lisäksi hyvin subjektiivisia. Kulttuurijohtajuus merkitsee kuitenkin nyt ja tulevaisuudessa kykyä olla innovatiivinen, joustava ja herkkä sosiaalisille merkityksille.
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In this thesis three experiments with atomic hydrogen (H) at low temperatures T<1 K are presented. Experiments were carried out with two- (2D) and three-dimensional (3D) H gas, and with H atoms trapped in solid H2 matrix. The main focus of this work is on interatomic interactions, which have certain specific features in these three systems considered. A common feature is the very high density of atomic hydrogen, the systems are close to quantum degeneracy. Short range interactions in collisions between atoms are important in gaseous H. The system of H in H2 differ dramatically because atoms remain fixed in the H2 lattice and properties are governed by long-range interactions with the solid matrix and with H atoms. The main tools in our studies were the methods of magnetic resonance, with electron spin resonance (ESR) at 128 GHz being used as the principal detection method. For the first time in experiments with H in high magnetic fields and at low temperatures we combined ESR and NMR to perform electron-nuclear double resonance (ENDOR) as well as coherent two-photon spectroscopy. This allowed to distinguish between different types of interactions in the magnetic resonance spectra. Experiments with 2D H gas utilized the thermal compression method in homogeneous magnetic field, developed in our laboratory. In this work methods were developed for direct studies of 3D H at high density, and for creating high density samples of H in H2. We measured magnetic resonance line shifts due to collisions in the 2D and 3D H gases. First we observed that the cold collision shift in 2D H gas composed of atoms in a single hyperfine state is much smaller than predicted by the mean-field theory. This motivated us to carry out similar experiments with 3D H. In 3D H the cold collision shift was found to be an order of magnitude smaller for atoms in a single hyperfine state than that for a mixture of atoms in two different hyperfine states. The collisional shifts were found to be in fair agreement with the theory, which takes into account symmetrization of the wave functions of the colliding atoms. The origin of the small shift in the 2D H composed of single hyperfine state atoms is not yet understood. The measurement of the shift in 3D H provides experimental determination for the difference of the scattering lengths of ground state atoms. The experiment with H atoms captured in H2 matrix at temperatures below 1 K originated from our work with H gas. We found out that samples of H in H2 were formed during recombination of gas phase H, enabling sample preparation at temperatures below 0.5 K. Alternatively, we created the samples by electron impact dissociation of H2 molecules in situ in the solid. By the latter method we reached highest densities of H atoms reported so far, 3.5(5)x1019 cm-3. The H atoms were found to be stable for weeks at temperatures below 0.5 K. The observation of dipolar interaction effects provides a verification for the density measurement. Our results point to two different sites for H atoms in H2 lattice. The steady-state nuclear polarizations of the atoms were found to be non-thermal. The possibility for further increase of the impurity H density is considered. At higher densities and lower temperatures it might be possible to observe phenomena related to quantum degeneracy in solid.
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The objective of the thesis was to create three tutorials for MeVEA Simulation Software to instruct the new users to the modeling methodology used in the MeVEA Simulation Software. MeVEA Simulation Software is a real-time simulation software based on multibody dynamics. The simulation software is designed to create simulation models of complete mechatronical system. The thesis begins with a more detail description of the MeVEA Simulation Software and its components. The thesis presents the three simulation models and written theory of the steps of model creation. The first tutorial introduces the basic features which are used in most simulation models. The basic features include bodies, constrains, forces, basic hydraulics and motors. The second tutorial introduces the power transmission components, tyres and user input definitions for the different components in power transmission systems. The third tutorial introduces the definitions of two different types of collisions and collision graphics used in MeVEA Simulation Software.
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This study is made as a part of the Chembaltic (Risks of Maritime Transportation of Chemicals in Baltic Sea) project which gathers information on the chemicals transported in the Baltic Sea. The purpose of this study is to provide an overview of handling volumes of liquid bulk chemicals (including liquefied gases) in the Baltic Sea ports and to find out what the most transported liquid bulk chemicals in the Baltic Sea are. Oil and oil products are also viewed in this study but only in a general level. Oils and oil products may also include chemical-related substances (e.g. certain bio-fuels which belong to MARPOL annex II category) in some cargo statistics. Chemicals in packaged form are excluded from the study. Most of the facts about the transport volumes of chemicals presented in this study are based on secondary written sources of Scandinavian, Russian, Baltic and international origin. Furthermore, statistical sources, academic journals, periodicals, newspapers and in later years also different homepages on the Internet have been used as sources of information. Chemical handling volumes in Finnish ports were examined in more detail by using a nationwide vessel traffic system called PortNet. Many previous studies have shown that the Baltic Sea ports are annually handling more than 11 million tonnes of liquid chemicals transported in bulk. Based on this study, it appears that the number may be even higher. The liquid bulk chemicals account for approximately 4 % of the total amount of liquid bulk cargoes handled in the Baltic Sea ports. Most of the liquid bulk chemicals are handled in Finnish and Swedish ports and their proportion of all liquid chemicals handled in the Baltic Sea is altogether over 50 %. The most handled chemicals in the Baltic Sea ports are methanol, sodium hydroxide solution, ammonia, sulphuric and phosphoric acid, pentanes, aromatic free solvents, xylenes, methyl tert-butyl ether (MTBE) and ethanol and ethanol solutions. All of these chemicals are handled at least hundred thousand tonnes or some of them even over 1 million tonnes per year, but since chemical-specific data from all the Baltic Sea countries is not available, the exact tonnages could not be calculated in this study. In addition to these above-mentioned chemicals, there are also other high volume chemicals handled in the Baltic Sea ports (e.g. ethylene, propane and butane) but exact tonnes are missing. Furthermore, high amounts of liquid fertilisers, such as solution of urea and ammonium nitrate in water, are transported in the Baltic Sea. The results of the study can be considered indicative. Updated information about transported chemicals in the Baltic Sea is the first step in the risk assessment of the chemicals. The chemical-specific transportation data help to target hazard or e.g. grounding/collision risk evaluations to chemicals that are handled most or have significant environmental hazard potential. Data gathered in this study will be used as background information in later stages of the Chembaltic project when the risks of the chemicals transported in the Baltic Sea are assessed to highlight the chemicals that require special attention from an environmental point of view in potential marine accident situations in the Baltic Sea area.
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OBJECTIVE: to evaluate the impact of the new technology of multidetector computed tomography (MDCT) in improving the accuracy and early diagnosis of BSBI.METHODS: patients with blunt small bowel injuries (BSBI) grade> I were identified retrospectively and their CT scans reviewed by an experienced radiologist. Clinical and tomographic findings were analyzed and patients grouped as "pre-MDCT" and "post-MDCT", according to the time of implementation of a 64-slice MDCT.RESULTS: of the 26 patients with BSBI 16 had CT scans. Motor vehicle collision (62.5%) was the most frequent mechanism of injury. In the pre-MDCT period, five of the 13 patients (38.5%) had abdominal CT, and in the post-MDCT, 11 of 13 patients (84.6%) had the exam. During pre-MDCT, all CT scans were abnormal with findings of pneumoperitoneum (60%), free fluid (40%) and bowel wall enhancement (20%). In the post-MDCT group, all exams but one were abnormal and the most frequent findings were free fluid (90.9%), bowel wall enhancement (72.7%), and pneumoperitoneum (54.5%). However, the rate of delayed laparotomy did not change. The mortality rate in both groups were similar, with 20% during pre-MDCT and 18.2% during post-MDCT.CONCLUSION: the use of MDCT in abdominal trauma in our service has increased the sensibility of the diagnosis, but has had no impact on outcome so far.
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Tutkimuksen kohteena on yksi sotilasyksikkö, Reserviupseerikoulun Esikunta- ja viestikomppania. Kyseisessä yksikössä koulutetaan reservinupseereita sotilaspo-liisi-, huolto-, johtamisjärjestelmä- ja komentopaikkatehtäviin. Sotilaspoliisilinja ja huoltolinja ovat liittyneet yksikköön vuoden 2014 lopulla. Tämä integraatio on saanut aikaan tiedonintressin koulutuslinjojen kulttuureihin liittyen. Tarkoituksena on selvittää miten linjojen koulutuskulttuurit poikkeavat toisistaan ja mitä kulttuurien integraatiossa tapahtuu. Tutkimuksen tavoitteena on myös antaa suosituksia yksikölle mahdollisten kulttuuriristiriitojen ja konfliktien hallitsemiseksi. Tutkimus on luonteeltaan sosiaaliantropologista kauppatieteellistä kulttuurintutki-musta. Taustatieteinä ovat liiketaloustiede, antropologia, sosiologia ja osittain or-ganisaatiopsykologia. Tutkimusote on laadullinen ja aineiston hankinnan mene-telminä on käytetty yksikön kouluttajien haastatteluja ja osallistuvaa havainnointia. Tutkimusaineisto on analysoitu teoriaohjaavaa laadullista sisällönanalyysiä käyttäen. Analyysin tavoitteena oli tunnistaa erot integroituvissa koulutuskulttuureissa, ymmärtää eroista johtuvien konfliktien logiikkaa ja tarkastella kulttuurien vuotamisen logiikkaa. Esikunta- ja viestikomppanian koulutuskulttuurien erilaisuutta analysoitiin seuraavien teoriateemojen kautta: oppilaskäsitys, suhtautuminen upseerioppilaisiin, artefaktit (koulutusmenetelmät), arvot, asenteet ja kouluttamisen syväoletukset. Koulutuskulttuurien kohtaamista analysoitiin psykologisen omistajuuden, reviirikäyttäytymisen ja kulttuurin vuotamisen teorioiden kautta. Tutkimustulokset osoittavat, että kulttuurilla todella on merkitystä sotilasorganisaa-tion integraatiotilanteessa. Esikunta- ja viestikomppanian koulutuskulttuureissa on havaittavissa huomattavia eroja, mutta myös samankaltaisuuksia. Kulttuurien erot johtavat ristiriitaisuuksiin, konflikteihin, reviirikäyttäytymiseen ja saavat ihmiset osoittamaan mieltään eri tavoin. Toisaalta kulttuuripiirteillä on myös taipumusta vuotaa ympäristöön nopeuttaen uusien organisaation osien sopeutumista. Johtajan rooli kulttuurien hallinnassa on keskeinen. Johtajan oma kulttuuriorientaatio voi johtaa konflikteihin, mutta toisaalta myös ratkaista niitä. Tärkeimpänä johtopäätöksenä on, että suuressa sotilasyksikössä kannattaisi laatia strategia eli suunnitelma kulttuurin johtamista varten silloin, kun integraatio on tapahtumassa. Strategian avulla voidaan ottaa kantaa useisiin kulttuurillisiin ristiriitoihin, joita siis Esikunta- ja viestikomppaniankin tapauksessa ilmenee. Koko yksikön henkilöstä kannattaisi sitouttaa ja ottaa mukaan strategian laadintaan. Strategia selventäisi esimerkiksi yksikön arvoja, visiota, missiota, tehtäviä, erilaisten linjojen erityisasemaa ja poikkeuksia, haluttua ja toivottua toimintaa ja asennetta, palkitsemiskäytäntöjä, toisin sanoen kulttuurin eri tekijöitä. Strategia ei ole vain liiketaloudellinen tulosyksikön pitkän tähtäimen pakollinen työkalu, vaan myös sotilasorganisaation kulttuurin johtamisen väline.
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Efonidipine hydrochloride is an antihypertensive and antianginal agent with fewer side effects and is better tolerated in the treatment of hypertension with renal impairment. Its interaction with bovine serum albumin (BSA) is of great use for the understanding of the pharmacokinetic and pharmacodynamic mechanisms of the drug. The binding of efonidipine to BSA was investigated by fluorescence spectroscopy and circular dichroism. BSA fluorescence was quenched by efonidipine, due to the fact that efonidipine quenched the fluorescence of tryptophan residues mainly by the collision mode. The thermodynamic parameters ΔH0 and ΔS0 were 68.04 kJ/mol and 319.42 J·mol-1·K-1, respectively, indicating that the hydrophobic interactions played a major role. The results of circular dichroism and synchronous fluorescence measurements showed that the binding of efonidipine to BSA led to a conformational change of BSA. The fraction of occupied sites (θ) for the 8-anilino-1-naphthalein-sulfonic acid (ANS)-BSA system is 85%, whereas for the NZ-105-BSA system, it is 53%, which suggests that the interaction of ANS with BSA is stronger than that of NZ-105 with BSA. Binding studies in the presence of ANS indicated that efonidipine competed with ANS for hydrophobic sites of BSA. The effects of metal ions on the binding constant of the efonidipine-BSA complex were also investigated. The presence of metal ions Zn2+, Mg2+, Al3+, K+, and Ca2+ increased the binding constant of efonidipine_BSA complex, which may prolong the storage period of NZ-105 in blood plasma and enhance its maximum effects.
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This paper analyses the recent performance of Brazilian exports, based on estimates of price and income elasticities of states external sellings. After presenting an overview of the national position, the aim is to check if, by exporting dynamic goods of high value, some of them were able to achieve an external position different from Brazilian's. Nevertheless, the results, as the ones obtained by other empirical works, indicate that all but one states have inelastic exports with respect to both prices and income.