Intrachain Energy Migration to Weak Charge-Transfer State in Polyfluorene End-Capped with Naphthalimide Derivative

Polyfluorene end-capped with N-(2-benzothiazole)-1 8-naphthalimide (PF-BNI) is a highly fluorescent material with fluorescence emission modulated by solvent polarity Its low energy excited state is assigned as a mixed configuration state between the singlet S(1) of the fluorene backbone (F) with the charge transfer (CI) of the end group BNI The triexponential fluorescence decays of PF-BNI were associated with fast energy migration to form an intrachain charge-transfer (ICCT) state polyfluorene backbone decay and ICCT deactivation Time-resolved fluorescence anisotropy exhibited biexponential relaxation with a fast component of 12-16 ps in addition to a slow one in the range 0 8-1 4 ns depending on the solvent showing that depolarization occurs from two different processes energy migration to form the ICCT state and slow rotational diffusion motion of end segments at a longer time Results from femtosecond transient absorption measurements agreed with anisotropy decay and showed a decay component of about 16 ps at 605 nm in PF BNI ascribed to the conversion of S(1) to the ICCT excited state From the ratio of asymptotic and initial amplitudes of the transient absorption measurement the efficiency of intrachain ICCT formation is estimated in 0 5 which means that on average, half of the excited state formed in a BNI-(F)(n)-BNI chain with n = 32 is converted to its low energy intrachain charge-transfer (ICCT) state

Axial ligand influence on geometries, charge distributions and electronic structures of iron tetraazamacrocycle [Fe((II))TIM(X)(Y)](2+) complexes assessed by Density Functional Theory

We employed the Density Functional Theory along with small basis sets, B3LYP/LANL2DZ, for the study of FeTIM complexes with different pairs of axial ligands (CO, H(2)O, NH(3), imidazole and CH(3)CN). These calculations did not result in relevant changes of molecular quantities as bond lengths, vibrational frequencies and electronic populations supporting any significant back-donation to the carbonyl or acetonitrile axial ligands. Moreover, a back-donation mechanism to the macrocycle cannot be used to explain the observed changes in molecular properties along these complexes with CO or CH(3)CN. This work also indicates that complexes with CO show smaller binding energies and are less stable than complexes with CH(3)CN. Further, the electronic band with the largest intensity in the visible region (or close to this region) is associated to the transition from an occupied 3d orbital on iron to an empty pi* orbital located at the macrocycle. The energy of this Metal-to-Ligand Charge Transfer (MLCT) transition shows a linear relation to the total charge of the macrocycle in these complexes as given by Mulliken or Natural Population Analysis (NPA) formalisms. Finally, the macrocycle total charge seems to be influenced by the field induced by the axial ligands. (C) 2011 Elsevier Ltd. All rights reserved.

Local Structure and Photochromic Response in Ormosils Containing Dodecatungstophosphoric Acid

Two hybrid materials based on dodecatungstophosphoric acid (HPW) dispersed in ormosils modified with 3-aminopropiltrietoxysilane (APTS) or with N-(3-(trimethoxysilyl)-propyl)-ethylene-diamine (TSPEN) show reversible photochromic response induced by irradiation in the 200-390 nm UV range. A set of solid-state nuclear magnetic resonance (NMR) techniques was used to analyze the structural properties of the main components of these hybrids (the HPW polyanion, the inorganic matrix, and the organic functionalities). For the ormosils, the use of (29)Si NMR, {(1)H}-(29)Si cross-polarization, and {(1)H}-(29)Si HETCOR revealed a homogeneous distribution of silicon species Q ``, T(2), and T(3) for the APTS hybrid, contrasting with the separation of T(3) species in the TSPEN hybrid. The combination of (31)P NMR, {(1)H}-(31)P cross-polarization and (31)P-{(1)H} spin-echo double resonance (SEDOR) revealed the dispersion of the HPW ions in the ormosil, occupying sites with a high number of close protons (>50). Differences in the molecular dynamics at room temperature, inferred from SEDOR experiments, indicate a state of restricted mobility of the HPW ion and the surrounding molecular groups in the TSPEN hybrid. This behavior is consistent with the presence of more amino groups in the TSPEN, acting as chelating groups to the HPW ion. This hybrid, with the strong chelate interaction of the diamine group, shows the most intense photochromic response, in agreement with the charge transfer models proposed to explain the photochromic effect. Electronic reflectance spectroscopy in irradiated samples revealed the presence of one-electron and two-electron reduced polyanions. The one-electron reduced species could be detected also by (31)P NMR spectroscopy immediately after UV irradiation.

Fast separation of selective serotonin reuptake inhibitors antidepressants in plasma sample by nonaqueous capillary electrophoresis

A simple, fast, and sensitive liquid-liquid extraction method followed by nonaqueous capillary electrophoresis (LLE/NACE) was developed and validated for Simultaneous determination of four antidepressants (fluoxetine, sertraline, citalopram and paroxetine) in human plasma. Several experimental separation conditions using aqueous and nonaqueous media separation were tested by varying the electrolyte pH value (for aqueous medium) and the ionic strength concentration considering the similar mobility of the compounds. High-resolution separation was achieved with a mixture of 1.25 mol L(-1) of phosphoric acid in acetonitrile. The quantification limits of the LLE/CE method varied between 15 and 30 ng mL(-1), with a relative standard deviation (RSD) lower than 10.3%. The method was successfully applied in therapeutic drug monitoring and should be employed in the evaluation of plasma levels in urgent toxicological analysis. (C) 2009 Elsevier B.V. All rights reserved.

TLC Separation and Identification of the Essential Oil Constituents from Aloysia gratissima

The present work had as objective the isolation of the five compounds by thin-layer Chromatography (TLC) from the essential oil of the Aloysia gratissima. For this, a number of systems of eluents were used for its separation, indicating that through the system acetone/hexane in proportions (v/v) 1:30 it was possible to isolate guaiol, elemol, pinocanphone (trans-3-pinanone), cis-pinocarvyl, and acorenone. The isolation of the compound acorenone from the other compounds was possible with the mixture of solvents hexane/dichloromethane in proportions (v/v) (1:1,3).

A Contour-based Separation of VerticallyAttached Traffic Signs

This report presents an algorithm for locating the cut points for and separatingvertically attached traffic signs in Sweden. This algorithm provides severaladvanced digital image processing features: binary image which representsvisual object and its complex rectangle background with number one and zerorespectively, improved cross correlation which shows the similarity of 2Dobjects and filters traffic sign candidates, simplified shape decompositionwhich smoothes contour of visual object iteratively in order to reduce whitenoises, flipping point detection which locates black noises candidates, chasmfilling algorithm which eliminates black noises, determines the final cut pointsand separates originally attached traffic signs into individual ones. At each step,the mediate results as well as the efficiency in practice would be presented toshow the advantages and disadvantages of the developed algorithm. Thisreport concentrates on contour-based recognition of Swedish traffic signs. Thegeneral shapes cover upward triangle, downward triangle, circle, rectangle andoctagon. At last, a demonstration program would be presented to show howthe algorithm works in real-time environment.

Barn och ungdomars upplevelser av separation sett ur ett omvårdnadsperspektiv. : Systematisk litteraturstudie.

Syftet med denna studie var att belysa barn och ungdomars erfarenheter, upplevelser och eventuella risk-och skyddsfaktorer i samband med föräldrarnas separation. Undersöka betydelsen av goda familjerelationer och vilka möjliga stödåtgärder sjuksköterskor kan använda för att hjälpa barn och ungdomar som inte mår bra av en separation.Metoden var utformad som en retrospektiv systematisk litteraturstudie och sökningar gjordes i databaser, framförallt via Högskolan Dalarna bibliotek. I resultatet framkommer hur barn upplever separationer, både positiva och negativa aspekter. Bra relationer både inom och utom familjen är viktiga för barnen vilket framkommer genomgående i arbetet. Umgängesföräldern har en viktig roll för barnen. Själva boendet spelar oftast inte så stor roll så länge barnen har bra relation till, regelbundet umgänge med, båda föräldrarna. Många riskfaktorer för barnen är ändå kopplade till separationer och barnen kan må psykiskt dåligt ända upp i vuxen ålder. Sjuksköterskan i barn- och skolhälsovården kan använda sig av olika verktyg för att hjälpa barn och föräldrar efter en separation. Familjefokuserad omvårdnad är en omvårdnadsmodell som lämpar sig väl för familjer i svåra och konfliktfyllda situationer.

Nyblivan föräldrars upplevelser av separation från sitt nyfödda barn efter förlossningen : en systematisk litteraturstudie

I olika sammanhang och i olika omfattning separeras mor och barn idag inom den perinatala vården. Då barnet behöver vård på neonatalavdelning leder det ofta till upprepad och långvarig separation mellan föräldrarna och barnet. Syftet med denna litteraturstudie är att beskriva föräldrars upplevelse av separation från sitt nyfödda barn efter förlossningen. Metod- studien är en systematisk litteraturstudie där 15 vetenskapliga artiklar ingår. Resultat- situationer som leder till separation mellan mamma och barn kan utgöra ett unikt tillfälle för pappan till nära kontakt och tidig anknytning mellan honom och barnet. Behovet att vara nära sitt barn är starkt och finns hos båda föräldrarna och separation leder till många negativa känslor och ökad stress hos föräldrarna samt utgör ett hinder för den tidiga anknytningen till barnet. Skillnader i behovet att vara nära barnet i den tidiga nyföddhetsperioden kan ses mellan mammor och pappor och mellan föräldrar till prematura barn och fullgångna. Nära hudkontakt och samvård mellan föräldrar och barn har visat sig ha många positiva effekter. Slutsatser- separation mellan föräldrar och barn har många negativa konsekvenser, såväl fysiska, psykiska som sociala. Kontinuerlig närhet efter förlossningen mellan mamman och det nyfödda barnet är viktigt och närhet mellan pappan och det nyfödda barnet är att föredra vid de tillfällen mor och barn måste separeras. Neonatal samvård skapar förutsättningar för en god anknytning mellan föräldrar och barn och ger möjlighet att påbörja föräldraskapet under optimala förutsättningar.

Separation and Execution of graphical engine on a cross platform IDE to enhance performance

“Biosim” is a simulation software which works to simulate the harvesting system.This system is able to design a model for any logistic problem with the combination of several objects so that the artificial system can show the performance of an individual model. The system will also describe the efficiency, possibility to be chosen for real life application of that particular model. So, when any one wish to setup a logistic model like- harvesting system, in real life he/she may be noticed about the suitable prostitution for his plants and factories as well as he/she may get information about the least number of objects, total time to complete the task, total investment required for his model, total amount of noise produced for his establishment in advance. It will produce an advance over view for his model. But “Biosim” is quite slow .As it is an object based system, it takes long time to make its decision. Here the main task is to modify the system so that it can work faster than the previous. So, the main objective of this thesis is to reduce the load of “Biosim” by making some modification of the original system as well as to increase its efficiency. So that the whole system will be faster than the previous one and performs more efficiently when it will be applied in real life. Theconcept is to separate the execution part of ”Biosim” form its graphical engine and run this separated portion in a third generation language platform. C++ is chosenhere as this external platform. After completing the proposed system, results with different models have been observed. The results show that, for any type of plants of fields, for any number of trucks, the proposed system is faster than the original system. The proposed system takes at least 15% less time “Biosim”. The efficiency increase with the complexity of than the original the model. More complex the model, more efficient the proposed system is than original “Biosim”.Depending on the complexity of a model, the proposed system can be 56.53 % faster than the original “Biosim”.

'In Charge of the Truffula Seeds' : On Children's Literature, Rationality and Children's Voices in Philosophy

In this paper I investigate how philosophy can speak for children and how children can have a voice in philosophy and speak for philosophy. I argue that we should understand children as responsible rational individuals who are involved in their own philosophical inquiries and who can be involved in our own philosophical investigations-not because of their rational abilities, but because we acknowledge them as conversational partners, acknowledge their reasons as reasons, and speak for them as well as let them speak for us and our rational community. In order to argue this I turn, first, to Gareth Matthews' philosophy of childhood and suggest a reconstruction of some of his concepts in line with the philosophy of Stanley Cavell. Second, in order to examine more closely our conceptions of rationality and our pictures of children, I consider the children's books, The Lorax and Where is My Sister? and Henrik Ibsen's play, The Wild Duck.

Contribuição ao beneficiamento de finos de fosfatos

Foram estudadas as características de floculação da hidro-xiapatita, calcita e quartzo com poliacrilamidas aniônicas. Tanto as suspensões de hidroxiapatita como a calcita foram completamente floculadas enquanto que o quartzo foi refratário a floculação com esses polimeros. Entretanto, observou-se que a floculação da calcita foi impedida com a utilização de um poliacrilato de sódio, enquanto que a hidroxiapatita continuou a ser floculada pela poliacrilamida num intervalo de concentração de O a 1000 g/ton de poliacrilato. Estes resultados permitiram estabelecer condições para a floculação seletiva de hidroxiapatita em misturas sintéticas com quartzo e calcita. Nestes sistemas foram estudados diversos parâmetros operacionais, tais como tipo de separação, efeito do teor da alimentação, e influência da moagem. Onde a separação estagiada apresentou melhor resultado, uma moagem adicional no sistema não favoreceu a seletividade. Por outro lado, o teor de P205 no concentrado é proporcional ao teor presente na alimentação. A hidroxiapatita, em estudo, de alta pureza (de acordo com técnicas de análise química, espectrofotometria de infravermelho e difração de raios X) apresentou um parto de carga zero em pH 6,77 na presença de diversos eletrólitos. A aplicação do sistema de floculação seletiva a fraçoes ultrafinas industriais foi estudada em detalhe e comparada com processos de flotação e floco-flatação. 0s resultados obtidos mostraram que a floculação seletiva somente foi eficiente nos sistemas sintéticos. A flotação, embora o minério apresente uma granulometria muito fina, foi mais eficiente que a floculação seletiva e a floco-flotação nos sistemas reais, em termos de taxa de enriquecimento e percentual de rejeição de massa. Entretanto com a floco-flotação foi possivel obter altas recuperações(-90%) para os minérios de Araxá e Itataia. Para o minério de Tapira, um aumento do teor de P2O5 foi obtido com a flotação da fração seletivamente floculada. As taxas de enriquecimento obtidas foram baixas (entre 1,35 e 2,101 em função das associações entre a apatita do minério com óxido de ferro e argila, o que revelou a caracterização mineralógica. Conclue-se que a concentração de minerios fosfatados de baixo teor é uma operação onerosa, onde o fator predominante é a absorção seletiva de reagentes e atransferência não específica de material de ganga nos respectivos concentrados.

An electroanalytical application of 2-aminothiazole-modified silica gel after adsorption and separation of Hg(II) from heavy metals in aqueous solution

2-Aminothiazole covalently attached to a silica gel surface was prepared in order to obtain an adsorbent for Hg(II) ions having the following characteristics: good sorption capacity, chemical stability under conditions of use, and, especially, high selectivity. The accumulation voltammetry of mercury(II) was investigated at a carbon paste electrode chemically modified with silica gel functionalized with 2-aminothiazole (SIAMT-CPE). The repetitive cyclic voltammogram of mercury(II) solution in the potential range -0.2 to + 0.6 V versus Ag/AgCl (0.02 mol L-1 KNO3; V = 20 mV s(-1)) show two peaks one at about 0.1 V and other at 0.205 V. The anodic wave peak at 0.205 V is well defined and does not change during the cycles and it was therefore further investigated for analytical purposes using differential pulse anodic stripping voltammetry in differents supporting electrolytes. The mercury response was evaluated with respect to pH, electrode composition, preconcentration time, mercury concentration, cleaning solution, possible interferences and other variables. The precision for six determinations (n = 6) of 0.02 and 0.20 mg L-1 Hg(II) was 4.1 and 3.5% (relative standard deviation), respectively. The detection limit was estimated as 0.10 mu g L-1 mercury(II) by means of 3:1 current-to-noise ratio in connection with the optimization of the various parameters involved and using the highest-possible analyser sensitivity. (c) 2006 Elsevier Ltd. All rights reserved.

Hypercapnic ventilatory response of anesthetized female rats subjected to neonatal maternal separation: Insight into the origins of panic attacks?

Neonatal maternal separation (NMS) is a form of stress that interferes with the regulation of the stress response, an effect that predisposes to the emergence of panic and anxiety related disorders. We previously showed that at adulthood, awake female (but not male) rats subjected to NMS show a hypercapnic ventilatory response (HCVR; 5% CO(2)) that is 63% greater than controls (Genest et al., 2007). To understand the mechanisms underlying the sex-specific effects of NMS on the ventilatory response to CO(2), we used two different anesthetized female rat preparations to assess central CO(2) chemosensitivity and contribution of sensory afferents (stretch receptors and peripheral chemoreceptors) that influence the HCVR. Data show that anesthesia eliminated the respiratory phenotype observed previously in awake females and CO(2) chemosensitivity did not differ between groups. Finally, the assessment of the ovarian hormone levels across the oestrus cycle failed to reveal significant differences between groups. Since anesthesia did not affect the manifestation of NMS-related respiratory dysfunction in males (including the hypercapnic ventilatory response) (Kinkead et al., 2005; Dumont and Kinkead, 2010), we propose that the panic or anxiety induced by CO(2) during wakefulness is responsible for enhancement of the HCVR in NMS females. (C) 2011 Elsevier B.V. All rights reserved.

Análise dos Processos de Flotação e Oxidação Avançada para o Tratamento de Efluente Modelo da Indústria do Petróleo

The generation of wastes in most industrial process is inevitable. In the petroleum industry, one of the greatest problems for the environment is the huge amount of produced water generated in the oil fields. This wastewater is a complex mixture and present great amounts. These effluents can be hazardous to the environmental without adequate treatment. This research is focused in the analysis of the efficiencies of the flotation and photo-oxidation processes to remove and decompose the organic compounds present in the produced water. A series of surfactants derivated from the laurilic alcohol was utilized in the flotation to promote the separation. The experiments have been performed with a synthetic wastewater, carefully prepared with xylene. The experimental data obtained using flotation presented a first order kinetic, identified by the quality of the linear data fitting. The best conditions were found at 0.029 g.L-1 for the surfactant EO 7, 0.05 g.L-1 for EO 8, 0.07 g.L-1 for EO 9, 0.045 g.L-1 for EO 10 and 0.08 g.L-1 for EO 23 with the following estimated kinetic constants: 0.1765, 0.1325, 0.1210, 0.1531 and 0.1699 min-1, respectively. For the series studied, the most suitable surfactant was the EO 7 due to the lower reagent onsumption, higher separation rate constant and higher removal efficiency of xylene in the aqueous phase (98%). Similarly to the flotation, the photo-Fenton process shows to be efficient for degradation of xylene and promoting the mineralization of the organic charge around 90% and 100% in 90 min