987 resultados para EXCHANGE-COUPLED GD2CU2
Resumo:
The present article aims to analyze the recent behavior of real exchange rate in Brazil and its effects over investment per worker in Brazilian manufacturing and extractive industry. Preliminary estimates presented in the article shows an over-valuation of 48% of real exchange rate in Brazil. The reaction between the level (and volatility) of real exchange rate and investment (per worker) in Brazil is analyzed by means of a panel data econometric model for 30 sectors of Brazilian manufacturing and extractive industry. The empirical results show that the level and volatility of real exchange rate has a strong effect over investment per worker in Brazilian industry. Finally, we conclude the article presenting a proposal for a new macroeconomic regime that aims to produce an acceleration of economic growth of Brazilian economy and, by that, a catching-up process with developed countries.
Resumo:
The debate on the link between trade rules and rules on exchange rates is raising the attention of experts on international trade law and economics. The main purpose of this paper is to analyze the impacts of exchange rate misalignments on tariffs as applied by the WTO - World Trade Organization. It is divided into five sections: the first one explains the methodology used to determine exchange rate misalignments and also presents its results for Brazil, U.S. and China; the second summarizes the methodology applied to calculate the impacts of exchange rate misalignments on the level of tariff protection through an exercise of "misalignment tariffication"; the third examines the effects of exchange rate variations on tariffs and their consequences for the multilateral trading system; the fourth one creates a methodology to estimate exchange rates against a currency of the World and a proposal to deal with persistent and significant misalignments related to trade rules. The conclusions are present in the last section.
Resumo:
The purpose of this article is twofold. The first is to explain the time inconsistencies of the convertibility regime that led to the 2001 crisis. The argument suggests that the credibility requirements for convertibility induced a dynamic of legal, fiscal, financial and external commitments that increased exit costs and time inconsistencies. The second objective is to explain the tensions of the floating regime that replaced convertibility in 2002. We describe the effects of a floating exchange rate on macroeconomic imbalance and the growing tension between competitiveness and inflation.
Resumo:
This thesis aims to investigate pricing of liquidity risks in London Stock Exchange. Liquidity Adjusted Capital Asset Pricing Model i.e. LCAPM developed by Acharya and Pedersen (2005) is being applied to test the influence of various liquidity risks on stock returns in London Stock Exchange. The Liquidity Adjusted Capital Asset Pricing model provides a unified framework for the testing of liquidity risks. All the common stocks listed and delisted for the period of 2000 to 2014 are included in the data sample. The study has incorporated three different measures of liquidity – Percent Quoted Spread, Amihud (2002) and Turnover. The reason behind the application of three different liquidity measures is the multi-dimensional nature of liquidity. Firm fixed effects panel regression is applied for the estimation of LCAPM. However, the results are robust according to Fama-Macbeth regressions. The results of the study indicates that liquidity risks in the form of (i) level of liquidity, (ii) commonality in liquidity (iii) flight to liquidity, (iv) depressed wealth effect and market return as well as aggregate liquidity risk are priced at London Stock Exchange. However, the results are sensitive to the choice of liquidity measures.
Resumo:
A method using L-cysteine for the determination of arsenous acid (As(III)), arsenic acid (As(V)), monomethylarsonic acid (MMAA), and dimethylarsinic acid (DMAA) by hydride generation was demonstrated. The instrument used was a d.c. plasma atomic emission spectrometer (OCP-AES). Complete recovery was reported for As(III), As(V), and DMAA while 86% recovery was reported for MMAA. Detection limits were determined, as arsenic for the species listed previously, to be 1.2, 0.8, 1.1, and 1.0 ngemL-l, respectively. Precision values, at 50 ngemL-1 arsenic concentration, were f.80/0, 2.50/0, 2.6% and 2.6% relative standard deviation, respectively. The L-cysteine reagent was compared directly with the conventional hydride generation technique which uses a potassium iodide-hydrochloric acid medium. Recoveries using L-cysteine when compared with the conventional method provided the following results: similar recoveries were obtained for As(III), slightly better recoveries were obtained for As(V) and MMAA, and significantly better recoveries for DMAA. In addition, tall and sharp peak shapes were observed for all four species when using L-cysteine. The arsenic speciation method involved separation by ion exchange .. high perfonnance liquid chromatography (HPLC) with on-line hydride generation using the L.. cysteine reagent and measurement byOCP-AES. Total analysis time per sample was 12 min while the time between the start of subsequent runs was approximately 20 min. A binary . gradient elution program, which incorporated the following two eluents: 0.01 and 0.5 mM tri.. sodium citrate both containing 5% methanol (v/v) and both at a pH of approximately 9, was used during the separation by HPLC. Recoveries of the four species which were measured as peak area, and were normalized against As(III), were 880/0, 290/0, and 40% for DMAA, MMAA and As(V), respectively. Resolution factors between adjacent analyte peaks of As(III) and DMAA was 1.1; DMAA and MMAA was 1.3; and MMAA and As(V) was 8.6. During the arsenic speciation study, signals from the d.c. plasma optical system were measured using a new photon-signal integrating device. The_new photon integrator developed and built in this laboratory was based on a previously published design which was further modified to reflect current available hardware. This photon integrator was interfaced to a personal computer through an AID convertor. The .photon integrator has adjustable threshold settings and an adjustable post-gain device.
Resumo:
Arsenic, bismuth, germanium, antimony and tin were simultaneously determined by continuous hydride generation and inductively coupled plasma-atomic emission spectrometry . I Hydrides were introduced into four different types of gas-liquid separators. Two of the gas-liquid separators were available in-house. A third was developed for this project and a fourth was based on a design used by CET AC. The best signal intensity was achieved by the type II frit-based gas-liquid separator, but the modified Cetac design gave promise for the future, due to low relative standard deviation. A method was developed for the determination of arsenic, bismuth, antimony and tin in low-alloy steels. Four standard reference materials from NIST were dissolved in 10 mL aqua regia without heat. Good agreement was obtained between experimental values and certified values for arsenic, bismuth, antimony and tin. The method was developed to provide the analyst with the opportunity to determine the analytes by using simple aqueous standards to prepare calibration lines. Within the limits of the samples analyzed, the method developed is independent of matrix.
Resumo:
Exch~nge energy of the He-He system is calculated using the one-density matrix which has been modified according to the supermolecular density formula quoted by Kolos. The exchange energy integrals are computed analytically and by the Monte Carlo method. The results obtained from both ways compared favourably,with the results obtained from the SCF program HONDO
Resumo:
Reactions of the boron halides with organic halides and organo-silicon compounds have been investigated. The results show exchange of halogens between the BX3 (X = Br# 1) and the organic halidef exchange of the halogen of the C-X bond being proved. The rates of halogen exchange vary. Reaction of the heavier halides with organo-silicon compounds indicated that the silicon-carbon bonds ruptured in the absence of electronegative atom attached to the silicon. The presence of an electronegative atom (halogen or oxygen) attached to the silicon causes the bond between the silicon and the electronegative atom to be preferentially broken. Products of exchange reactions of the boron halides and the organic halides or the organo-silicon compounds were studied by use of 1H NMR and GC/MS. From these results some possible mechanisms for the exchange reactions are postulated, but further work is indicated to prove the real courses of the reactions
Resumo:
Exchange reactions between molecular complexes and excess acid
or base are well known and have been extensively surveyed in the
literature(l). Since the exchange mechanism will, in some way
involve the breaking of the labile donor-acceptor bond, it follows
that a discussion of the factors relating to bonding in molecular complexes
will be relevant.
In general, a strong Lewis base and a strong Lewis acid form a
stable adduct provided that certain stereochemical requirements are
met.
A strong Lewis base has the following characteristics (1),(2)
(i) high electron density at the donor site.
(ii) a non-bonded electron pair which has a low ionization potential
(iii) electron donating substituents at the donor atom site.
(iv) facile approach of the site of the Lewis base to the
acceptor site as dictated by the steric hindrance of the
substituents.
Examples of typical Lewis bases are ethers, nitriles, ketones,
alcohols, amines and phosphines.
For a strong Lewis acid, the following properties are important:(
i) low electron density at the acceptor site.
(ii) electron withdrawing substituents. (iii) substituents which do not interfere with the close
approach of the Lewis base.
(iv) availability of a vacant orbital capable of accepting
the lone electron pair of the donor atom.
Examples of Lewis acids are the group III and IV halides such
(M=B, AI, Ga, In) and MX4 - (M=Si, Ge, Sn, Pb).
The relative bond strengths of molecular complexes have been
investigated by:-
(i)
(ii)
(iii)
(iv)
(v]
(vi)
dipole moment measurements (3).
shifts of the carbonyl peaks in the IIIR. (4) ,(5), (6) ..
NMR chemical shift data (4),(7),(8),(9).
D.V. and visible spectrophotometric shifts (10),(11).
equilibrium constant data (12), (13).
heats of dissociation and heats of reactions (l~),
(16), (17), (18), (19).
Many experiments have bben carried out on boron trihalides in
order to determine their relative acid strengths. Using pyridine,
nitrobenzene, acetonitrile and trimethylamine as reference Lewis
bases, it was found that the acid strength varied in order:RBx3 >
BC1
3 >BF 3
• For the acetonitrile-boron trihalide and trimethylamine
boron trihalide complexes in nitrobenzene, an-NMR study (7) showed
that the shift to lower field was. greatest for the BB~3 adduct ~n~
smallest for the BF 3 which is in agreement with the acid strengths. If electronegativities of the substituents were the only
important effect, and since c~ Br ,one would expect
the electron density at the boron nucleus to vary as BF3
Resumo:
A simple, low-cost concentric capillary nebulizer (CCN) was developed and evaluated for ICP spectrometry. The CCN could be operated at sample uptake rates of 0.050-1.00 ml min'^ and under oscillating and non-oscillating conditions. Aerosol characteristics for the CCN were studied using a laser Fraunhofter diffraction analyzer. Solvent transport efficiencies and transport rates, detection limits, and short- and long-term stabilities were evaluated for the CCN with a modified cyclonic spray chamber at different sample uptake rates. The Mg II (280.2nm)/l\/lg 1(285.2nm) ratio was used for matrix effect studies. Results were compared to those with conventional nebulizers, a cross-flow nebulizer with a Scott-type spray chamber, a GemCone nebulizer with a cyclonic spray chamber, and a Meinhard TR-30-K3 concentric nebulizer with a cyclonic spray chamber. Transport efficiencies of up to 57% were obtained for the CCN. For the elements tested, short- and long-term precisions and detection limits obtained with the CCN at 0.050-0.500 ml min'^ are similar to, or better than, those obtained on the same instrument using the conventional nebulizers (at 1.0 ml min'^). The depressive and enhancement effects of easily ionizable element Na, sulfuric acid, and dodecylamine surfactant on analyte signals with the CCN are similar to, or better than, those obtained with the conventional nebulizers. However, capillary clog was observed when the sample solution with high dissolved solids was nebulized for more than 40 min. The effects of data acquisition and data processing on detection limits were studied using inductively coupled plasma-atomic emission spectrometry. The study examined the effects of different detection limit approaches, the effects of data integration modes, the effects of regression modes, the effects of the standard concentration range and the number of standards, the effects of sample uptake rate, and the effect of Integration time. All the experiments followed the same protocols. Three detection limit approaches were examined, lUPAC method, the residual standard deviation (RSD), and the signal-to-background ratio and relative standard deviation of the background (SBR-RSDB). The study demonstrated that the different approaches, the integration modes, the regression methods, and the sample uptake rates can have an effect on detection limits. The study also showed that the different approaches give different detection limits and some methods (for example, RSD) are susceptible to the quality of calibration curves. Multicomponents spectral fitting (MSF) gave the best results among these three integration modes, peak height, peak area, and MSF. Weighted least squares method showed the ability to obtain better quality calibration curves. Although an effect of the number of standards on detection limits was not observed, multiple standards are recommended because they provide more reliable calibration curves. An increase of sample uptake rate and integration time could improve detection limits. However, an improvement with increased integration time on detection limits was not observed because the auto integration mode was used.
Resumo:
A research project submitted to the Faculty of Extension, University of Alberta in partial fulfillment of the requirements for the degree of Master of Arts in Communications and Technology in 2005.
Resumo:
Picture Exchange Communication System (PECS) is an augmentative and alternative communicative system that improves communication and decreases problem behaviors in children with Developmental Disabilities and Autism. The mediator model is a validated approach that clinicians use to train parents to perform evidence-based interventions. Parental non-adherence to treatment recommendations is a documented problem. This qualitative study investigated clinician-perceived factors that influence parental adherence to PECS recommendations. Three focus groups (n=8) were conducted with Speech Language Pathologists and Behavior Therapists experienced in providing parents with PECS recommendations. Constant comparison analysis was used. In general, clinicians believed that PECS was complex to implement. Thirty-one bridges were identified to overcome complexity. Twenty-two barriers and 6 other factors also impacted parental adherence. Strategies to address these factors were proposed based on a review of the literature. Future research will be performed to validate these findings using parents and a larger sample size.
Resumo:
Hypoxia in plant tissue should affect animals living within. Gallmakers stimulate their plant hosts to produce the gall they inhabit and feed on, and also influence the gall phenotype for other adaptations, such as defense against predators. The potential for hypoxia in galls of Eurosta solidaginis was studied in the context of potential adaptations to gall oxygen level, using a combination of direct measurement, mathematical modelling, and respirometry on both gallmakers and hosts. Modelling results suggested mild hypoxia tolerable to the larva persists for most of the growth season, whereas more severe hypoxia may occur earlier in fully-grown young galls. Field data from one of the two years studied showed hypoxia more severe than expected, and coincided with adverse weather conditions and high larval mortality. The hypoxia may be related to host response to adverse weather. Whether hypoxia directly caused larval mortality requires further study.
Resumo:
Part I: Ultra-trace determination of vanadium in lake sediments: a performance comparison using O2, N20, and NH3 as reaction gases in ICP-DRC-MS Thermal ion-molecule reactions, targeting removal of specific spectroscopic interference problems, have become a powerful tool for method development in quadrupole based inductively coupled plasma mass spectrometry (ICP-MS) applications. A study was conducted to develop an accurate method for the determination of vanadium in lake sediment samples by ICP-MS, coupled with a dynamic reaction cell (DRC), using two differenvchemical resolution strategies: a) direct removal of interfering C10+ and b) vanadium oxidation to VO+. The performance of three reaction gases that are suitable for handling vanadium interference in the dynamic reaction cell was systematically studied and evaluated: ammonia for C10+ removal and oxygen and nitrous oxide for oxidation. Although it was able to produce comparable results for vanadium to those using oxygen and nitrous oxide, NH3 did not completely eliminate a matrix effect, caused by the presence of chloride, and required large scale dilutions (and a concomitant increase in variance) when the sample and/or the digestion medium contained large amounts of chloride. Among the three candidate reaction gases at their optimized Eonditions, creation of VO+ with oxygen gas delivered the best analyte sensitivity and the lowest detection limit (2.7 ng L-1). Vanadium results obtained from fourteen lake sediment samples and a certified reference material (CRM031-040-1), using two different analytelinterference separation strategies, suggested that the vanadium mono-oxidation offers advantageous performance over the conventional method using NH3 for ultra-trace vanadium determination by ICP-DRC-MS and can be readily employed in relevant environmental chemistry applications that deal with ultra-trace contaminants.Part II: Validation of a modified oxidation approach for the quantification of total arsenic and selenium in complex environmental matrices Spectroscopic interference problems of arsenic and selenium in ICP-MS practices were investigated in detail. Preliminary literature review suggested that oxygen could serve as an effective candidate reaction gas for analysis of the two elements in dynamic reaction cell coupled ICP-MS. An accurate method was developed for the determination of As and Se in complex environmental samples, based on a series of modifications on an oxidation approach for As and Se previously reported. Rhodium was used as internal standard in this study to help minimize non-spectral interferences such as instrumental drift. Using an oxygen gas flow slightly higher than 0.5 mL min-I, arsenic is converted to 75 AS160+ ion in an efficient manner whereas a potentially interfering ion, 91Zr+, is completely removed. Instead of using the most abundant Se isotope, 80Se, selenium was determined by a second most abundant isotope, 78Se, in the form of 78Se160. Upon careful selection of oxygen gas flow rate and optimization ofRPq value, previous isobaric threats caused by Zr and Mo were reduced to background levels whereas another potential atomic isobar, 96Ru+, became completely harmless to the new selenium analyte. The new method underwent a strict validation procedure where the recovery of a suitable certified reference material was examined and the obtained sample data were compared with those produced by a credible external laboratory who analyzed the same set of samples using a standardized HG-ICP-AES method. The validation results were satisfactory. The resultant limits of detection for arsenic and selenium were 5 ng L-1 and 60 ng L-1, respectively.
Resumo:
Consumption of low-fat milk (LFM) after resistance training has been shown to have positive influences on body composition and training adaptations; however, little research has examined the effects of LFM consumption following endurance training. The purpose of the study was to look at the effects of combining additional servings of LFM following endurance exercise on body composition, bone health, and training adaptations. 40 healthy males were recruited. Individuals were randomized into 4 groups – DEI (750mL LFM immediately post exercise), DEA (750mL LFM 4 hrs prior to or 6 hrs post exercise), CEI (750mL carbohydrate beverage immediately post-exercise), and CEA (750mL carbohydrate beverage immediately post-exercise). Participants took part in a 12-week endurance training intervention (1 h/day, 3 d/wk, ~60% max HR). 22 participants completed the study. Analysis showed significant increases in lean mass, spinal bone mineral content, relative VO2peak, and a decrease in Trap 5β across all groups (p < 0.05).