931 resultados para State, The


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While it is widely believed that the use of amnesties and similar measures would mark a new departure in NI and the UK, so that speculation about their introduction causes public controversy and threatens political instability, the report demonstrates that such measures have in fact been repeatedly used in a wide range of circumstances since the foundation of the NI state. The paper offers definitions of the key measures which have been employed, including amnesties, sentence reductions linked to peace building and use immunities. It explores their historical use and its consequences.

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Despite the appeal and significance of nationalism as a near universal political force, Irish historians – in common with the historians of most nationalist movements – have struggled to analyse nationalism from beyond the perspective of the nation state. The reasons for this are varied, arising both from practical aspects, such as the availability and accessibility of sources, to more conceptual issues such as the resilience of the national perspective in the framing of historiographical narratives. This paper considers the Easter Rising as a case study in assessing how a transnational framework complicates traditional historiographical perspectives. Accounts of the Easter Rising generally interpret the rebellion within local, national, or international (particularly Anglo-Irish or imperial) frameworks. Interpretations that adopt a broader framework have tended to focus on international rather than transnational dimensions: the First World War context, revolutionary links with Germany, and the role of the United States. This paper assesses the potential of a transnational approach by analysing four aspects of the Rising: the significance of the transnational movement of people prior to the event; the influence of the transnational circulation of political ideas; the impact of transnational cultural currents in shaping the framing of revolutionary ideals; and the impact of the Rising on Irish nationalist communities beyond Ireland.

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The current design plans for the International Thermonuclear\nExperimental Reactor ( ITER) call for tungsten to be employed for\ncertain plasma facing components in the divertor region. Thus, accurate\natomic collision data are needed for emission modelling of tungsten.\nElectron-impact excitation and radiative rates are of particular\nimportance for Ni-like W, since this ion emits some of the most intense\nspectral lines of all ionization stages. We report on a fully\nrelativistic 115-level R-matrix calculations of W46+, which includes the\neffects of radiation damping. Although radiation damping is very\nimportant in most highly ionized species, its effects are reduced in\nthis case because of the closed-shell Ni-like ground state. The rates\nfrom these relativistic atomic calculations will be employed for\ncollisional-radiative modelling of this ion.

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In co-melt granulation, collisions occur between the particles to be agglomerated and the binder material. Depending on the stage of granulation, the binder material can be in the solid or liquid phase. The outcome of these collisions controls the dynamics of the granulation process and the fundamental physics of the impacts are of interest. This paper examines the impact of glass beads (model particles) and solid Poly Ethylene Glycol (PEG) flakes on a substrate of PEG as the temperature of the PEG layer is increased from below its melting point to above it. While the layer is in the solid state, the result of the impact can be quantified by the coefficient of restitution. When the layer is in the liquid state, the impact can be quantified by the immersion behaviour. The results obtained show that the coefficient of restitution between either glass beads and PEG flakes and the PEG layer is strongly affected by temperatures. As the PEG layer approaches its melting point, the coefficient of restitution falls to zero. Once the temperature of the PEG layer exceeds the melting point, the impact is characterised by a transient maximum indentation and then rebound to an equilibrium position. These too are strongly dependent on temperature.

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A génese de um cancro está dependente da acumulação de mutações genéticas que dão origem a instabilidade genómica, que por sua vez resulta na proliferação descontrolada. Para prevenir a acumulação destas mutações, as células têm mecanismos de controlo (checkpoints) que suspendem o ciclo celular e accionam as vias de reparação do ADN. Estes eventos são muitas vezes regulados por dinâmicas de (des)fosforilação de proteínas. As proteínas fosfatases (PPs), enzimas responsáveis pela remoção do grupo fosfato de resíduos fosforilados, desempenham funções cruciais na regulação de muitos mecanismos celulares. Enquanto que no início do projecto as cinases envolvidas no checkpoint da replicação estavam bem estabelecidas, as PPs envolvidas não eram conhecidas. A Chk1, um componente da maquinaria do checkpoint da replicação, é exemplo dessa regulação por (des)fosforilação, como sejam nos resíduos Ser317 e Ser345. Assim, como primeira abordagem para determinar quais os grupos de PPs envolvidos na regulação do checkpoint da replicação, decidimos investigar o seu papel na regulação da fosforilação da Chk1. A primeira conclusão é que a desfosforilação da Chk1 ao longo do tempo, tanto in vivo como in vitro, ocorre com uma dinâmica bi-fásica. Em segundo, a abordagem in vitro sugere que as famílias PP1, PP2A e PP2C estão envolvidas na desfosforilação da Chk1. Uma vez que a família PP2A foi a que mostrou a maior acção nesta reacção, decidimos investigar outros membros da família in vivo, primeiro com uma abordagem geral (tratando com OA ou sobreexpressando a PME-1), e depois com o knockdown específico da PP4 e PP6 (através de siRNA). Os resultados mostram que a inibição das PPs afectam tanto a desfosforilação como o estado de activação da Chk1 em resposta a tratamento com Hidroxiureia (HU). Todas as PPs testadas in vivo pareceram ser capazes de regular, a níveis diferentes, tanto a fosforilação como a desfosforilação da Chk1. A função das PPs foi também investigada ao nível: da regulação do disparo das origens de replicação, e da recuperação da suspensão da replicação, induzida pela HU. No último caso, os dados indicam que na situação simultânea de knockdown da PP4 com tratamento de HU, há um atraso do ciclo celular na resolução da transição de G2/M. No ensaio de replicação por pulse-chase, os resultamos mostram que tanto o tratamento com OA, como a sobre-expressão de I-2 ou PME-1, atrasam a cronologia do disparo programado das origens de replicação. No entanto, nenhum dos tratamentos efectuados parece desregular o início do checkpoint da replicação. Um rastreio de 2-híbrido de levedura com uma biblioteca de cDNA de testículo humano foi realizado, usando a Chk1 como isco, no sentido de descobrir novos interactores e definir novas possíveis funções para a Chk1 no contexto da meiose. Com base nos resultados do rastreio, duas novas funções são sugeridas: a interacção com a GAGE12 sugere uma função na recombinação genómica/vigilância do genoma durante a meiose, e as interacções com a EEF1α1 e a RPS5 sugerem uma função na regulação da síntese proteíca. Estas experiências fornecem um visão geral para a compreensão da diversidade de funções das proteínas fosfatases envolvidas no checkpoint da replicação, bem como, abre novos caminhos para o desenvolvimento de novas drogas para o tratamento do cancro.

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Governor Moses calls on South Carolinians to endeavor to become a respected member of the United States following the U.S. Civil War. His message addresses the status of the national debt, South Carolina public education, the South Carolina Orphan Asylum, the South Carolina Lunatic Asylum, the state penitentiary, the state’s quarantine of small pox, the revenue-generating phosphate deposits in the state, immigration to the state, the state’s flagship university, current state legislation, and the state militia.

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In September 2014, a historic referendum on the issue of Scottish independence was held, with the potential to dissolve the political union between Scotland and the other constituent nations of the United Kingdom which had survived intact since the 1707 Act of Union. On a significantly high electoral turnout of 84.6%, the Scottish electorate opted to reject the proposals of the governing party in the devolved Scottish Parliament, the pro-independence Scottish National Party (SNP), to create an independent Scottish state, with 55.3% of the electorate voting ‘No’ to Scottish independence against a 44.7% ‘Yes’ vote. In the grand scheme of the Scottish independence referendum campaigns, sports policy remained a somewhat peripheral issue within the arguments forwarded by the Yes Scotland and Better Together campaigns. Nonetheless, developments such as the formation of the 'Sport for Yes' campaign sub-group, the inclusion of sport within the Scottish Government’s White Paper on Scottish independence and the establishment of the Working Group on Scottish Sport demonstrated that the potential implications of independence were still deemed significant enough to merit a degree of policy planning by the Scottish Government (Lafferty, 2014; Scottish Government, 2013; Working Group on Scottish Sport, 2013, 2014). This paper will critically consider the implications of the 'No' vote in the Scottish independence referendum for the latter of these developments, the policy proposals of the Working Group for Scottish Sport. Drawing upon the principles of critical discourse analysis, specifically the analytical framework proposed by Fairclough and Fairclough (2012), the content of this group's proposal will be examined in order to critically explore the policy for Scottish sport it envisaged for an independent Scottish state. The paper will then conclude by reflecting upon the extent to which elements of this political 'imaginary' (Fairclough and Fairclough, 2012) of Scottish sport remain a possibility for future sports policy in Scotland following the eventual 'No' vote in the referendum.

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Volatile organic compounds are a common source of groundwater contamination that can be easily removed by air stripping in columns with random packing and using a counter-current flow between the phases. This work proposes a new methodology for the column design for any particular type of packing and contaminant avoiding the necessity of a pre-defined diameter used in the classical approach. It also renders unnecessary the employment of the graphical Eckert generalized correlation for pressure drop estimates. The hydraulic features are previously chosen as a project criterion and only afterwards the mass transfer phenomena are incorporated, in opposition to conventional approach. The design procedure was translated into a convenient algorithm using C++ as programming language. A column was built in order to test the models used either in the design or in the simulation of the column performance. The experiments were fulfilled using a solution of chloroform in distilled water. Another model was built to simulate the operational performance of the column, both in steady state and in transient conditions. It consists in a system of two partial non linear differential equations (distributed parameters). Nevertheless, when flows are steady, the system became linear, although there is not an evident solution in analytical terms. In steady state the resulting system of ODE can be solved, allowing for the calculation of the concentration profile in both phases inside the column. In transient state the system of PDE was numerically solved by finite differences, after a previous linearization.

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Volatile organic compounds are a common source of groundwater contamination that can be easily removed by air stripping in columns with random packing and using a counter-current flow between the phases. This work proposes a new methodology for column design for any type of packing and contaminant which avoids the necessity of an arbitrary chosen diameter. It also avoids the employment of the usual graphical Eckert correlations for pressure drop. The hydraulic features are previously chosen as a project criterion. The design procedure was translated into a convenient algorithm in C++ language. A column was built in order to test the design, the theoretical steady-state and dynamic behaviour. The experiments were conducted using a solution of chloroform in distilled water. The results allowed for a correction in the theoretical global mass transfer coefficient previously estimated by the Onda correlations, which depend on several parameters that are not easy to control in experiments. For best describe the column behaviour in stationary and dynamic conditions, an original mathematical model was developed. It consists in a system of two partial non linear differential equations (distributed parameters). Nevertheless, when flows are steady, the system became linear, although there is not an evident solution in analytical terms. In steady state the resulting ODE can be solved by analytical methods, and in dynamic state the discretization of the PDE by finite differences allows for the overcoming of this difficulty. To estimate the contaminant concentrations in both phases in the column, a numerical algorithm was used. The high number of resulting algebraic equations and the impossibility of generating a recursive procedure did not allow the construction of a generalized programme. But an iterative procedure developed in an electronic worksheet allowed for the simulation. The solution is stable only for similar discretizations values. If different values for time/space discretization parameters are used, the solution easily becomes unstable. The system dynamic behaviour was simulated for the common liquid phase perturbations: step, impulse, rectangular pulse and sinusoidal. The final results do not configure strange or non-predictable behaviours.

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RESUMO: A Nigéria tem uma população estimada em cerca de 170 milhões de pessoas. O número de profissionais de saúde mental é muito diminuto, contando apenas com 150 psiquiatras o que perfaz aproximadamente um rácio de psiquiatra: população de mais de 1:1 milhão de pessoas. O Plano Nacional de Saúde Mental de 1991 reconheceu esta insuficiência e recomendou a integração dos serviços de saúde mental nos cuidados de saúde primários (CSP). Depois de mais de duas décadas, essa política não foi ainda implementada. Este estudo teve como objetivos mapear a estrutura organizacional dos serviços de saúde mental da Nigéria, e explorar os desafios e barreiras que impedem a integração bem-sucedida dos serviços de saúde mental nos cuidados de saúde primários, isto segundo a perspectiva dos profissionais dos cuidados de saúde primários. Com este objetivo, desenvolveu-se um estudo exploratório sequencial e utilizou-se um modelo misto para a recolha de dados. A aplicação em simultâneo de abordagens qualitativas e quantitativas permitiram compreender os problemas relacionados com a integração dos serviços de saúde mental nos CSP na Nigéria. No estudo qualitativo inicial, foram realizadas entrevistas com listagens abertas a 30 profissionais dos CSP, seguidas de dois grupos focais com profissionais dos CSP de duas zonas governamentais do estado de Oyo de forma a obter uma visão global das perspectivas destes profissionais locais sobre os desafios e barreiras que impedem uma integração bem-sucedida dos serviços de saúde mental nos CSP. Subsequentemente, foram realizadas entrevistas com quatro pessoas-chave, especificamente coordenadores e especialistas em saúde mental. Os resultados do estudo qualitativo foram utilizados para desenvolver um questionário para análise quantitativa das opiniões de uma amostra maior e mais representativa dos profissionais dos CSP do Estado de Oyo, bem como de duas zonas governamentais locais do Estado de Osun. As barreiras mais comummente identificadas a partir deste estudo incluem o estigma e os preconceitos sobre a doença mental, a formação inadequada dos profissionais dos CPS sobre saúde mental, a perceção pela equipa dos CSP de baixa prioridade de ação do Governo, o medo da agressão e violência pela equipa dos CSP, bem como a falta de disponibilidade de fármacos. As recomendações para superar estes desafios incluem a melhoria sustentada dos esforços da advocacia à saúde mental que vise uma maior valorização e apoio governamental, a formação e treino organizados dos profissionais dos cuidados primários, a criação de redes de referência e de apoio com instituições terciárias adjacentes, e o engajamento da comunidade para melhorar o acesso aos serviços e à reabilitação, pelas pessoas com doença mental. Estes resultados fornecem indicações úteis sobre a perceção das barreiras para a integração bem sucedida dos serviços de saúde mental nos CSP, enquanto se recomenda uma abordagem holística e abrangente. Esta informação pode orientar as futuras tentativas de implementação da integração dos serviços de saúde mental nos cuidados primários na Nigéria.------------ABSTRACT: Nigeria has an estimated population of about 170 million people but the number of mental health professionals is very small, with about 150 psychiatrists. This roughly translates to a psychiatrist:population ratio of more than 1:1 million people. The National Mental Health Policy of 1991 recognized this deficiency and recommended the integration of mental health into primary health care (PHC) delivery system. After more than two decades, this policy has yet to be implemented. This study aimed to map out the organizational structure of the mental health systems in Nigeria, and to explore the challenges and barriers preventing the successful integration of mental health into primary health care, from the perspective of the primary health care workers. A mixed methods exploratory sequential study design was employed, which entails the use of sequential timing in the combined methods of data collection. A combination of qualitative and uantitative approaches in sequence, were utilized to understand the problems of mental health services integration into PHC in Nigeria. The initial qualitative phase utilized free listing interviews with 30 PHC workers, followed by two focus group discussions with primary care workers from two Local Government Areas (LGA) of Oyo State to gain useful insight into the local perspectives of PHC workers about the challenges and barriers preventing successful integration of mental health care services into PHC. Subsequently, 4 key informant interviews with PHC co-ordinators and mental health experts were carried out. The findings from the qualitative study were utilized to develop a quantitative study questionnaire to understand the opinions of a larger and more representative sample of PHC staff in two more LGAs of Oyo State, as well as 2 LGAs from Osun State. The common barriers identified from this study include stigma and misconceptions about mental illness, inadequate training of PHC staff about mental health, low government priority, fear of aggression and violence by the PHC staff, as well as non-availability of medications. Recommendations for overcoming these challenges include improved and sustained efforts at mental health advocacy to gain governmental attention and support, organized training and retraining for primary care staff, establishment of referral and supportive networks with neighbouring tertiary facilities and community engagement to improve service utilization and rehabilitation of mentally ill persons. These findings provide useful insight into the barriers to the successful integration of mental health into PHC, while recommending a holistic and comprehensive approach. This information can guide future attempts to implement the integration of mental health into primary care in Nigeria.

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Personality traits and personal values are two important domains of individual differences. Traits are enduring and distinguishable patterns of behaviour whereas values are societally taught, stable, individual preferences that guide behaviour in order to reach a specific end state. The purpose of the present study was to investigate the relations between self and peer report within the domains of personality traits and values, to examine the correlations between values and traits, and to explore the amount of incremental validity of traits and values in predicting behaviour. Two hundred and fiftytwo men and women from a university setting completed self and peer reports on three questionnaires. In order to assess personality traits, the HEXACO-PI (Lee & Ashton, 2004) was used to identify levels of 6 major dimensions of personality in participants. To assess values, the Schwartz Value Survey (Schwartz, 1992) was used to identify the importance each participant placed on each of Schwartz's 10 value types. To measure behaviour, a Behavior Scale, created by Bardi and Schwartz (2003), consisting of items designed to measure the frequency of value-expressive behaviour was used. As expected, correlations between self and peer reports for the personality scales were high indicating that personality traits are easily observable to other people. Correlations between self and peer reports for the values and behaviour scales were only moderate, suggesting that some goals, and behaviours expressive of those goals, may not always be observable to others. Consistent with previous research, there were many strong correlations between traits and values. In addition to the similarities with past research, the present study found that the personality factor Honesty-Humility was correlated strongly with values scales (with five correlations exceeding .25). In the prediction of behaviour, it was found that both personahty and values were able to account for significant and similar amounts of variance. Personality outpredicted values for some behaviours, but the opposite was true of other behaviours. Each domain provided incremental validity beyond the other domain. The impUcations for these findings, along with limitations, and possibilities for future research are also discussed.

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A comprehensive elemental, isotopic and microstructural analyses was undertaken of brachiopod calcites from the Hamilton Group (Middle Devonian), Clinton Group (Middle Silurian) and Middle to Upper Ordovician strata of Ontario and New York State. The majority of specimens were microstructurally and chemically preserved in a pristine state, although a number of specimens show some degree of post-depositional alteration. Brachiopod calcites from the Hamilton and Clinton Groups were altered by marine derived waters whereas Trenton Group (Middle Ordovician) brachiopods altered in meteorically derived fluids. Analysis of the elemental and isotopic compositions of pristine Hamilton Group brachiopods indicates there are several chemical relationships inherent to brachiopod calcite. Taxonomic differentiation of Mg, Sr and Na contents was evident in three co-occuring species from the Hamilton Group. Mean Mg contents of pristine brachiopods were respectively Athyris spiriferoides (1309ppm), Mucrospirifer mucronatus (1035ppm) and Mediospirifer audacula (789ppm). Similarly, taxonomic differentiation of shell calcite compositions was observed in co-occuring brachiopods from the Clinton Group (Middle Silurian) and the Trenton Group (Middle Ordovician). The taxonomic control of elemental regulation into shell calcite is probably related to the slightly different physiological systems and secretory mechanisms. A relationship was observed in Hamilton Group species between the depth of respective brachiopod communities and their Mg, Sr and Na contents. These elements were depleted in the shell calcites of deeper brachiopods compared to their counterparts in shallower reaches. Apparently shell calcite elemental composition is related to environmental conditions of the depositional setting, which may have controlled the secretory regime, mineral morphology of shell calcite and precipitation rates of each species. Despite the change in Mg, Sr and Na contents between beds and formations in response to environmental conditions, the taxonomic differentiation of shell calcite composition is maintained. Thus, it may be possible to predict relative depth changes in paleoenvironmental reconstructions using brachiopod calcite. This relationship of brachiopod chemistry to depth was also tested within a transgressiveregressive (T-R) cycle in the Rochester Shale Formation (Middle Silurian). Decreasing Mg, Sr and Na contents were observed in the transition from the shallow carbonates of the Irondequoit Formation to the deeper shales of the lowest 2 m of Rochester Shale. However, no isotopic and elemental trends were observed within the entire T-R cycle which suggests that either the water conditions did not change significantly or that the cycle is illusory. A similar relationship was observed between the Fe and Mn chemistries of shell calcite and redox/paleo-oxygen conditions. Hamilton Group brachiopods analysed from deeper areas of the shelf are enriched in Mn and Fe relative to those from shallow zones. The presence of black shales and dysaerobic faunas, during deposition of the Hamilton Group, suggests that the waters of the northern Appalachian Basin were stratified. The deeper brachiopods were marginally positioned above an oxycline and their shell calcites reflect periodic incursions of oxygen depleted water. Furthermore, analysis of Dalmanella from the black shales of the Collingwood Shale (Upper Ordovician) in comparison to those from the carbonates of the Verulam Formation (Middle Ordovician) confirm the relationship of Fe and Mn contents to periodic but not permanent incursions of low oxygen waters. The isotopic compositions of brachiopod calcite found in Hamilton Group (813C; +2.5% 0 to +5.5% 0; 8180 -2.50/00 to -4.00/00) and Clinton Group (813C; +4.00/00 to +6.0; 8180; -1.8% 0 to -3.60/ 00) are heavier than previously reported. Uncorrected paleotemperatures (assuming normal salinity, 0% 0 SMOW and no fractionation effects) derived from these isotopic values suggest that the Clinton sea temperature (Middle Silurian) ranged from 18°C to 28°C and Hamilton seas (Middle Devonian) ranged between 24°C and 29°C. In addition, the isotopic variation of brachiopod shell calcite is significant and is related to environmental conditions. Within a single time-correlative shell bed (the Demissa Bed; Hamilton Group) a positive isotopic shift of 2-2.5% 0 in 013C compositions and a positive shift of 1.0-1.50/00 in 0180 composition of shell calcite is observed, corresponding with a deepening of brachiopod habitats toward the axis of the Appalachian Basin. Moroever, a faunal succession from deeper Ambocoelia dominated brachiopod association to a shallow Tropidoleptus dominated assocation is reflected by isotopic shifts of 1.0-1.50/00. Although, other studies have emphasized the significance of ±20/oo shifts in brachiopod isotopic compositions, the recognition of isotopic variability in brachiopod calcite within single beds and within depositional settings such as the Appalachian Basin has important implications for the interpretation of secular isotopic trends. A significant proportion of the variation observed isotopic distribution during the Paleozoic is related to environmental conditions within the depositional setting.

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This research was focussed on the effects of light, solvent and substituents in the molybdenum-catalyzed oxidation of phenylmethyl sulfides with t-Bu02H and on the effect of light in the molybdenum-catalyzed epoxidation of l-octene with t-Bu02H. It was shown that the Mo(CO)6-catalyzed oxidation of phenylmethyl sulfide with t-Bu02H~ at 35°C, proceeds 278 times faster underUV light than under laboratory lighting, whereas the Mo02(acac)2-catalyzed oxidation proceeds only 1.7 times faster under UV light than under normal laboratory lighting. The difference between the activities of both catalysts was explained by the formation of the catalytically active species, Mo(VI). The formation of the Mo(VI) species, from Mo(CO)6 was observed from the IR spectrum of Mo(CO)6 in the carbonyl region. The Mo(CO)6-catalyzed epoxidation of l-octene with t-Bu02H showed that the reaction proceeded 4.6 times faster under UV light than in the dark or under normal laboratory lighting; the rates of epoxidations were found to be the same in the dark and under normal laboratory lighting. The kinetics of the epoxidations of l-octene with t-Bu02H, catalyzed by Mo02(acac)2 were found to be complicated; after fast initial rates, the epoxidation rates decreased with time. The effect of phenylmethyl sulfide on the Mo(CO)6-catalyzed epoxidation of l-octene waS studied. It was shown that instead of phenylmethyl sulfide, phenylmethyl sulfone, which formed rapidly at 85°C, lowered the reaction rate. The epoxidation of l-octene was found to be 2.5 times faster in benzene than in ethanol. The substituent effect on the Mo02(acac)2-catalyzed oxidations of p-OH, p-CHgO, P-CH3' p-H, p-Cl, p-Br, p-CHgCO, p-HCO and P-N02 substituted phenylmethyl sulfides were studied. The oxidations followed second order kinetics for each case; first order dependency on catalyst concentration was also observed in the oxidation of p-CHgOPhSMeand PhSMe. It was found that electron-donating groups on the para position of phenylmethyl sulfide increased the rate of reaction, while electronwithdrawing groups caused the reaction rate to decrease. The reaction constants 0 were determined by using 0, 0- and 0* constants. The rate effects were paralleled by the activation energies for oxidation. The decomposition of t-Bu02H in the presence of M.o (CO)6, Mo02 (acac)2 and VO(acac)2 was studied. The rates of decomposition were found to be very small compared to the oxidation rates at high concentration of catalysis. The relative rates of the Mo02(acac)2-catalyzed oxidation of p-N02PhSMe by t-Bu02H in the presence of either p-CH30PhSMe or PhSMe clearly show that PhSMe and p-CHgOPhSMe act as co-catalysts in the oxidation of p-N02PhSMe. Benzene, mesity1ene and cyclohexane were used to determine the effect of solvent in the Mo02 (acac)2 and Mo(CO)6-catalyzed oxidation of phenylmethyl sulfide. The results showed that in the absence of hydroxylic solvent, a second molecule of t-Bu02H was involved in the transition state. The complexation of the solvent with the catalyst could not be explained.The oxidations of diphenyl sulfoxide catalyzed by VO(acac)2, Mo(CO)6 and Mo02(acac)2 showed that VO(acac)2 catalyzed the oxidation faster than Mo(CO)6 and Mo02 (acac)2_ Moreover, the Mo(CO)6-catalyzed oxidation of diphenyl sulfoxide proceeded under UV light at 35°C.

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The 3700 A - 3000 A absorption spectra of CH3CHO and its isotopic compounds such as CH3CDO, CD3CHO and CD3CDO were studied in the gas phase at room temperature and low temperatures. The low resolution spectra of the compounds were recorded by a 1.5 m Baush and Lomb grating spectrograph. The high resolution spectra were recorded by a Ebert spectrograph with the Echelle grating and the holographic grating separately. The multiple reflection cells were used to achieve the long path length. The pressure-path length used for the absorption spectrum of CH 3CHO was up to 100 mm Hg )( 91 . 43mo The emission spectrum and the excitation spectrum of CH3CHO were also recorded in this research. The calculated satellite band patterns \vhich were ob-tailied by the method of Lewis were used to compare with the observed near UV absorption spectrum of acetaldehyde. These calculated satellite band patterns belonged to two cases: namely, the barriers-in-phase case and the barriers- out-of-phase case. Each of the calculated patterns corresponded to a stable conformation of acetaldehyde in the excited state . The comparisons showed that the patterns in the observed absorption spectra corresponded to the H-H eclipsed conformations of acetaldehyde in the excited state . The least squares fitting analysis showed that the barrier heights in the excited state were higher than in the ground state. Finally, the isotopic shifts for the isotopic compounds of acetaldehyde were compared to the compounds with the similar deuterium substitution.