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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
301

Monitoring and evaluation mechanisms for sustainable development in Sedibeng District Municipality

Zwane, Engeline January 2014 (has links)
In South Africa, democracy has brought transformative improvement in the system of governance. The Constitution of the Republic of South Africa (1996) implemented in the post-apartheid era, has raised the status of the lowest sphere of government, by granting these authorities delegated responsibilities. This sphere of governance is known as local government (municipal government) and in the present context developmental local government is both democratically elected and decentralized. The restructuring of local governance requires municipalities to serve the communities within their areas of jurisdiction. This has brought capacity challenges for the municipalities. They are charged with delivering acceptable standards of services to the residents. The current lack of deliverance is evident in the widespread protests, with community members showing their dissatisfaction with sub-standard service delivery and backlogs. Furthermore, municipalities are required to formulate their own by-laws improve the lives of community members, and to implement their legislative mandates satisfactorily. In order for the municipalities to perform more effectively, a transformative model is necessary. The quality of services currently delivered at municipal level must be reviewed. Monitoring and evaluation are the key elements of assessment which must be undertaken. The rationale behind this monitoring and evaluation is to make the system of governance more effective through an even-handed assessment of policies, programmes, projects, strategies, performance of personnel, and the organization as a whole. For the purpose of this study, the researcher explored the challenges regarding monitoring and evaluation and its impact on sustainable development in Sedibeng District Municipality utilizing the quantitative research approach. A model is proposed for improvement called as Monitoring and Evaluation for Sustainable Development (MESD). / PhD (Public Management and Governance), North-West University, Vaal Triangle Campus, 2014
302

TELEMETRY PROCESSING SYSTEMS DESIGN TRENDS

Yates, James William 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / Current changes in the way that large flight test systems are utilized have affected the industry’s methodology in both the early design phases and in the implementation of nextgeneration hardware and software. The reduction of available RF spectrum, the implementation of packet telemetry methods and systems, and a desire to implement commercial-off-the-shelf (COTS) hardware are only some of the considerations that telemetry systems integrators and product houses have to face. This paper describes how test methodology changes affect current large systems design at both government test ranges and at airframe/missile manufacturer test facilities. In addition, consideration is given to the area of increased processing power as it affects hardware and software design, the leveraging of such current and future telecommunications technology as network switch technology and compression, cross utilization, standardized technology, and the movement toward platform-independent software.
303

從優勢競爭替代之觀點探討垂直市場競爭者之戰略型投資

韓行一, Han,Henry Unknown Date (has links)
企業的持續成長是每一家企業所追求的目標之一,也是衡量企業營運績效之重要指標,當一個企業成長趨緩或開始衰退時,往往是企業遭遇困難的警訊。而企業能持續成長端賴競爭力之保有及持續提升,這在企業就必須具有企業競爭優勢策略,因而企業競爭優勢策略是提升企業經營績效的重要課題。 營運成長模式一般可分為內部成長與外部成長。內部成長是指經由公司內部新事業、新產品或新訂單與新客戶的增加使營業額成長;外部成長則是藉由外部策略聯盟、轉投資、購併等手段使公司能取得有利競爭優勢與地位或擴大營業規模。又因為藉由轉投資與購併經常能使企業之規模與競爭力獲得跳躍式成長,如美國通用電氣(General Electric)與思科(Cisco corp.)均為明顯而成功的案例,故在大部分企業經營時,其成為很多企業成長策略的主要選項。 然而,企業在選擇轉投資、策略聯盟或購併行為時,其策略與目標的訂定、購併與被購併企業之定位、整合;購併或轉投資的標的選擇與評估、計畫的規劃與執行等等,均影響外部成長之成敗,導致企業競爭力是否持續增進。 本研究針對垂直市場的產業內聯盟與轉投資為限制範圍,以聚焦於”垂直市場”產業內之轉投資有別於跨產業之投資行為,以”優勢競爭替代”之觀點來探討企業策略定位,以”組織變革”觀點來觀察購併與被購併或投資者與被投資者之定位策略與執行策略,以”累積長期競爭優勢”為標準來衡量與檢驗聯盟或轉投資之效益。 本研究針對研華股份有限公司轉投資艾訊股份有限公司之策略聯盟個案,以探索性研究方法依理論比較實務,研究其在策略聯盟之過程,探討此個案之策略與執行過程,期望能對研華與艾訊公司之策略作一研究與檢討並提出後續改進之建議。 本研究之歸納發現為: 一、 垂直市場競爭者之水平式策略聯盟或購併,如僅由發揮最大生產效率之綜效來考量,不易累積長久之競爭優勢。 二、 在垂直市場產業中,卓越的聯盟或購併之策略運用,在清楚的分析所處市場特性與公司定位以持續維持競爭優勢是策略思考的核心。 三、 破壞性創新思維運用在市場競爭策略上,市場在位者可提升維持性創新競爭力並同時可建立低階策略聯盟以形成阻止其他低階攻擊者障礙,足以保護現有市場在位領先者免於被競爭者侵蝕競爭力。形成結構上的長期競爭優勢。 四、 購併策略之執行,是否應將被併購企業併入,端賴兩方公司之策略定位。依據定位來檢視雙方之資源、流程與價值三個構面,當此三構面在雙方整合對整體策略有助益,則雙方應合併,反之則應維持獨立運作。 五、 雖然處於相同產業,但競爭之主要成功因素將因企業為維持性創新之市場在位者,或是防止低階、低價進攻者之阻攻者角色而有所改變;相對應的組織變革就應提出以確保策略之成功執行。 / The continuous revenue growth is one of the utmost goals that every enterprise seeks. It is also one of the key factors to measure the operation efficiency of an enterprise. It is an alarming signal that the enterprise is encountering serious challenges whenever the sales growth stays slow or encounters a recession. In order to keep the revenue grow consistently, an enterprise needs to sustain its competitiveness and keep its ascendancy as its cutting edge strategy. We can classify the growth engines into two categories: first, the internal growth engine which is contributed by new business, new products, and new orders; second, the external growth engine which is contributed by strategic alliances, M&A, and other investment opportunities. The enterprise usually gets a quantum jump on its business scale when a successful Merger & Acquisition is executed. The General Electric Co. and Cisco Co. cases are good examples of M&A. This probably explains why many companies place M&A and investment opportunity on high priority when setting growth strategies. However, when an enterprise adopts strategic alliance, M&A or diversified investment, its success depends heavily on its abilities of goal setting, positioning, targeting of Alliance Company, doing due-diligence, and solving culture conflict. This thesis investigates the strategic alliances and diversification investment between vertical market players, to focus on monistic industrial investment instead of cross industrial investment; reviews the company positioning strategy from the point of ascendancy competitiveness strategy; studies the execution of organization change between merger and merged companies and verifies the effectiveness of strategic alliances from the viewpoint of accumulated long term competitiveness advantages. The thesis studies from theoretical research to the case study of Advantech Co. which applies the exploratory research method. The Advantech Co. conducted an alliance with Axiomtek Co. in 2002 by stock swap between the two companies. Advantech owns 65% of Axiomtek after the alliance. It is my purpose to assay the process of strategic alliance and try to provide some advices to improve the effectiveness of this strategy. Conclusions can be summarized as follows 1. The strategic alliances or diversification investment between vertical market players can contribute less for cumulating the competitiveness if it is targeted to prevail by maximizing the production efficiency synergy. 2. A superior alliance strategy in vertical market is to analyze the market attributes and anchor the company positioning which helps the competitiveness accumulating for a player. 3. By implementing the disruptive innovation theory in market competition strategy, one company can develop alliance with a lower cost, 2nd tier or less functionality product provider to create the barrier for protecting attack from the disruptive competitors. 4. The resources, process and value are three scopes to judge whether two companies need be combined as one company or not. When those three measurements are formulating more advantages after combining based on mergers decision on companies positioning strategy, then, it should be combined as one company, otherwise vice versa. 5. The key success factors will be reformed accordingly if the acquirer re-positioning the company. A correspondent organization change also is recommended to be implemented.
304

Le rôle de l’avocat dans les transactions d’acquisition et fusion d’entreprises

Malian, Paul A. 08 1900 (has links)
Les développements technologiques et la mondialisation ont permis aux gens d’avoir accès à l’information plus facilement et rapidement que jamais, provoquant ainsi des changements importants dans le milieu juridique qui doit s’adapter à la nouvelle clientèle sophistiquée et exigeante. Dans ce travail, nous nous penchons sur certains aspects devant être considérés par les avocats modernes assistant leur clientèle dans le cadre des transactions d’acquisition et de fusion. / Technological advancements and globalisation have allowed people to access information more rapidly and easily than ever, thus provoking significant changes in the legal profession to adapt to the new sophisticated and demanding clientele. In this research, we focus on certain aspects needed to be considered by modern lawyers in assisting their clients in the context of merger and acquisition transactions.
305

管理層收購法律規範理論與實務—台日比較 / M&A laws relating to management buyouts : theory and practice between Taiwan and Japan

張雅涵 Unknown Date (has links)
本論文為管理層收購法律規範理論與實務之研究,比較台灣與日本兩國法律規範及實務運作方式,借鏡上市公司股權結構及管理層收購發動背景與我國相似之日本,檢討我國管理層收購之相關法規範,並試提出修正建議。 在管理層收購下,管理層一方面為收購方,一方面亦為目標公司之決策機構,其間之利益衝突不言而喻,且管理層收購亦伴隨著逐出少數股東之下市交易,如何能確保交易公平並保障少數股東之利益,為各國法規範管理層收購之一大重點。 本文以2011年國際私募基金Kohlberg Kravis Roberts & Co. L.P.來台收購我國半導體大廠國巨股份有限公司一案帶入我國管理層收購之法規範及實務運作,並點出該案及其後一連串之修法下我國法仍存在之問題,再探討日本法下管理層收購之相關規範及實務運作模式,並以日本兩實務案例:日立集團旗下之日立機材株式會社創始股東聯合國際私募基金凱雷集團發動管理層收購事件、日本判決著名案件Rex Holdings管理層收購事件兩案,深入探討日本法之管理層收購實務運作及相關判決,最後則以兩國實務案例比較,進一步檢討我國法之問題。
306

財務顧問在跨國購併案件中對主併公司之價值 / The value of financial advisors for acquirers in cross-border M&As

陳怡廷, Chen, Yi Ting Unknown Date (has links)
全球化下,企業之競爭日益激烈且為了整合資源與拓展新市場,全球跨國購併案件逐漸增加。全球跨國購併案件增加的同時,也彰顯了財務顧問在跨國購併案件中扮演之角色與價值。財務顧問之職責主要為客戶降低各方面之成本,以及為客戶談妥好議價、購併後帶來綜效。本研究主要從財務顧問之角度出發,探討不同特性財務顧問之價值以及聚焦在跨國購併案件。跨國購併案件較複雜,更能彰顯財務顧問在跨國購併案件中之價值與效應。 本研究主要從兩個角度探討不同特性之財務顧問,分別為精品(Boutique)之財務顧問以及過去績效好之財務顧問,探究兩者在跨國購併案件中能為主併公司帶來多少價值。更進一步探究,在不同且複雜之交易特性下,不同特性之財務顧問在跨國購併案件中能為主併公司帶來何價值。 本研究之結果發現,精品(Boutique)財務顧問與過去三年績效佳之財務顧問,兩者皆能為主併公司帶來顯著的正向效應。且在跨國購併案件中,若被併公司屬於未上市公司,兩種特性之財務顧問皆能為主併公司帶來顯著之正效果。進一步發現,精品(Boutique)且過去三年績效佳之財務顧問,能為主併公司帶來較大之價值。在跨國購併案件中,不僅在被併公司為未上市時帶來顯著之正效應外,且在交易特性為非現金支付的情況下,也能為主併公司帶來顯著之正向價值。 / This study examines the value of financial advisors for acquirers in cross-border M&As and the impacts of deal outcomes. Two hypotheses are tested in the study:“Boutique” financial advisors create much more values for acquirers in cross-border M&As. The other one is financial advisors whose prior client performances were good, create much more values for acquirers in cross-border M&As. The study finds that“Boutique” financial advisors and financial advisors whose prior client performances were good both can create positive value for acquirers in cross-border M&As. Moreover, both can deal with complex transactions. While the target are private firms, both can create positive value for acquirers in cross-border M&A. In conclusion, the“Boutique” financial advisors whose prior clients performances were good create much more values for acquirers in cross-border M&As, and it can deal with more complex transactions.
307

家族企業世代併購決策:以台灣上市櫃公司為例 / M&A decisions across generations:the evidence of Taiwanese family firms

吳婉禎, Wu, Wan Chen Unknown Date (has links)
過去許多國內外的研究顯示,由創業者所經營之家族企業公司績效表現與投資決策優於由接班者所經營之家族企業和非家族企業。然而,台灣過去卻鮮少有文獻探討創業者與接班者在投資決策上的主要差異,以及是否在特定的公司治理特性下可以協助創業者和接班者做決策,進一步增加公司價值。 本研究主要以2010年至2014年間台灣上市櫃家族企業作為樣本,並將樣本分為由創業者所經營之家族企業與接班者所經營之家族企業,探討由創業者經營之家族企業與接班者所控制之經營企業在併購決策上是否有所不同,在何種公司治理特性或是公司特色可使併購宣告效果增加。本研究以兩階段迴歸和事件研究法作為研究方法,第一部分分析創業者與接班者在公司經營績效上之差異,第二部分分析創業者與接班者在併購宣告效果上的差異,最後進一步分析,何種公司治理特性或是公司特色可使併購宣告之累積異常報酬增加。實證結果顯示,創業者所經營之公司經營績效較佳,且由創業者所作之併購決策,能夠顯著提升併購宣告之累積異常報酬。此外,本研究發現外部董事比例越高,對於投資人預期之累積異常報酬顯著負向效果;然而外部股東持股對於併購宣告之累積異常報酬則有正向之加強效果。 / Past studies indicate that founder-family firms exhibit better firm performance and investment decisions than successor-family firms and non-family firms. However, little research has examined the difference in investment decisions across generations (founders and successors) in Taiwan. Moreover, it is unclear whether there exist some specific firm characteristics or corporate governance structure arrangements that can improve the decision-making of corporate investment to enhance firm value. This study employs the family firms and M&A data during the period of 2010 to 2014 in Taiwan to examine whether M&A decisions differ across family generations in Taiwan. Through the two-stage least squares regression analysis and the event study analysis, we find that the founder-family firms have better firm performance than successor-family firms. The founder-family firms also earn higher acquisition announcement returns than successor-family firms. Besides, we show that the percentage of outside directors has a negative effect on the acquisition announcement returns while the largest outside ownership is positively correlated with the acquisition announcement returns.
308

Estudo da degradação do dietil ftalato por processo eletroquímico com ânodo dimensionalmente estável em sistemas aquosos / Study of the degradation of diethyl phthalate by electrochemical process with anode dimensionally stable in aqueous systems

Medina, Ana Maria Barbosa 25 April 2016 (has links)
Os ésteres de ftalato (PAEs) são compostos produzidos em grandes quantidades, amplamente utilizados industrialmente como agentes plastificantes. Seus resíduos são lixiviados pela água tornando-se poluentes orgânicos persistentes (POPs) no meio ambiente aquoso, além de apresentar características de interferência endócrina. O dietil ftalato (DEP) é frequentemente encontrado nas amostras ambientais, pois possui elevada solubilidade na água e pode ser gerado durante a degradação de outros PAEs. Assim, este trabalho teve como objetivo a degradação do dietil ftalato em meio aquoso por método eletroquímico utilizando um ânodo dimensionalmente estável (ADE) comercial representado como Ti/Ru0,3Ti0,7O2 em uma célula do tipo filtro-prensa. As eletrólises foram de 120 minutos contendo uma concentração inicial de 100,3 mg L-1 de DEP, pH inicial igual a 3, a temperatura em 25 °C e vazão em 250 mL min-1. Os experimentos foram feitos utilizando planejamento fatorial do tipo 32 com duas réplicas no ponto central, apresentando como variáveis independentes a densidade de corrente (10, 25 e 40 mA cm-2) e o logaritmo em base 10 da forca iônica do eletrólito suporte, NaCl e Na2SO4 (µ = 0,05, 0,15 e 0,5 mol L-1), com o intuito de estudar o efeito da densidade de corrente, concentração e natureza do eletrólito para determinar a melhor condição de degradação do dietil ftalato. O monitoramento da concentração do DEP foi feito com cromatografia líquida de alta eficiência (CLAE) e a mineralização foi acompanhada pelas análises de carbono orgânico total (COT). Foram obtidas maiores porcentagens de remoção e mineralização com uso das maiores densidades de corrente e na presença de altas concentrações de NaCl em comparação com Na2SO4. Dessa maneira, se obteve remoção de 63,2 % e mineralização de 63,9 % em solução 0,5 mol L-1 NaCl e densidade de corrente de 40 mA cm-2, enquanto que para Na2SO4 (µ = 0,5 mol L-1) e 40 mA cm-2 foi removido 51,3 % e mineralizado 53,0 % de DEP. O mecanismo de degradação de DEP foi determinado em meio de NaCl e Na2SO4, através de CLAE-MS nas condições citadas anteriormente, identificando-se os íons moleculares de m/z 149 e 177 em ambos eletrólitos, correspondentes ao anidrido ftálico protonado e ao aduto do anidrido ftálico com C(2)H(5)(+) respectivamente, íons característicos da fragmentação do DEP, além do íon m/z 239 em Na2SO4 correspondente ao dietil 3-hidroxiftalato. A degradação do DEP acontece através da cadeia alifática. / Phthalate esters (PAEs) are compounds produced in large amounts industrially widely used as plasticizers. Their waste are leached by water becoming persistent organic pollutants (POPs) in the aqueous environment, besides having endocrine disrupting characteristics. Diethyl phthalate (DEP) is frequently found in environmental samples, it has high solubility in water and can be generated during the degradation of other PAEs. This work studied the degradation of diethyl phthalate in aqueous media by electrochemical method using a commercial dimensionally stable anode (ADE) represented as Ti/Ru0,3Ti0,7O2 in a filter-press flow cell. The electrolysis were carried out during 120 minutes containing an initial concentration of 100.3 mg L-1 DEP, initial pH = 3, temperature at 25 °C and flow rate of 250 ml min-1. The experiments were performed using factorial design 32 with two replicas at the midpoint, with as independent variables the current density (10, 25 and 40 mA cm-2) and the logarithm base 10 of the ionic strength of the electrolyte, NaCl and Na2SO4 (µ = 0.05, 0.15 and 0.5 mol L-1), in order to study the effect of current density, concentration and nature of the electrolyte to determine the best diethyl phthalate degradation condition. The monitoring of DEP concentration was made by high-performance liquid chromatography (HPLC) and the mineralization was accompanied by total organic carbon (TOC) analysis. They obtained higher percentages of removal and mineralization with the use of higher current densities and in the presence of high concentrations of NaCl in comparison with Na2SO4. Thus, there was obtained the removal of 63.2 % and 63.9 % mineralization in 0.5 mol L-1 NaCl and current density of 40 mA cm-2, whereas for Na2SO4 (µ = 0.5 mol L-1) and 40 mA cm-2 was removed 51.3 % and 53.0% mineralized DEP. The DEP degradation mechanism was determined in NaCl and Na2SO4, by HPLC-MS under the conditions mentioned above, identifying the molecular ion of m/z 149 and 177 on both electrolytes, corresponding to protonated phthalic anhydride and an adduct of phthalic anhydride with C(2)H(5)(+), respectively, characteristic ions of DEP fragmentation, besides the ion m/z 239 over Na2SO4 corresponding to diethyl 3-hydroxyphthalate. The DEP degradation takes place through the aliphatic chain.
309

Reação do mercado em fusões & aquisições Cross-border de firmas brasileiras

Takenouchi, Pedro Issao 05 December 2012 (has links)
Made available in DSpace on 2016-04-25T18:39:52Z (GMT). No. of bitstreams: 1 Pedro Issao Takenouchi.pdf: 873574 bytes, checksum: 3107214bd8624b830f017c093e21ca11 (MD5) Previous issue date: 2012-12-05 / The primary objective of this study is to examine the market reaction to cross-border acquisitions of Brazilian multinational emerging-companies (MECs). On this purpose, we examine 128 mergers and acquisitions announcements associated with 36 (MECs) during the sample period 2000 2011. The mergers and acquisitions announcements data come from the Thomson SDC Platinum database. On this dissertation was employed the event study methodology to measure the impact of the announcements on the value of acquiring firms. Herein were established as windows event, 11, 15 and 5 days; furthermore, as windows estimation, were adopted 120, 240 and 500 days. Resulting in a total of 1,140 analysis of merger and acquisition from the original sample. Thus, the results show that, on average, cross-border acquisitions of MECs do not create value to the acquirers. Moreover, in order to explore the influencing factors of the direction and magnitude of market reaction; herein, were deeply analyzed some explanatory variables based on Resource-based View (RBV) and the cross border acquisitions literature, through stratifying event studies results, applying ordinary least square regression, and besides, a non parametric statistical analysis; yclept, bootstrap. Thereby, the empirical findings provide evidence that economic distance, acquisitions on developed countries, past performance, firm size, periods of crises and recessions, serial acquirers, among others variables; as performance drivers for Brazilian s (MECs) cross-border acquisition / Este trabalho tem como objetivo examinar a reação de mercado em aquisições internacionais (cross-border) realizadas por empresas brasileiras. Foram examinados 128 anúncios, públicos e concluídos, de fusões e aquisições (F&A) de 36 firmas brasileiras, no período de 2000 a 2011. Os dados de F&A foram obtidos da base de dados da Thomson SDC Platinum e foi utilizada a metodologia de estudo de eventos (MacKinlay, 1997; McWilliams & Siegel 1997), para mensurar o impacto resultante do anúncio de F&A sobre o valor de mercado da firma adquirente. Foram utilizados como janelas de evento (11, 15 e 5 dias) e, como janelas de estimação (120, 240 e 500 dias), resultando em um total de 1.140 análises de fusões e aquisições para a amostra da pesquisa. Como achado da pesquisa, foi encontrado que, na média, as aquisições internacionais não criaram valor para as firmas adquirentes brasileiras. Outrossim, com o intuito de verificar quais fatores influenciaram no desempenho das transações de aquisições cross border das empresas brasileiras, com base na literatura de Resource-based View (RBV) (Penrose, 1959; Aybar & Ficici, 2009; Gubbi et al., 2010), foram realizados estudos de eventos estratificados, regressão por mínimos quadrados ordinário e análise estatística não paramétrica bootstrap. Onde verificou-se que os fatores distância econômica, aquisição em país desenvolvido, desempenho passado, o tamanho da firma, períodos de crises e recessão, adquirentes seriais, entre outros; são variáveis direcionadoras para o desempenho em relação à reação de mercado a fusões e a aquisições cross-border realizadas por firmas brasileiras
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Estudo da degradação do dietil ftalato por processo eletroquímico com ânodo dimensionalmente estável em sistemas aquosos / Study of the degradation of diethyl phthalate by electrochemical process with anode dimensionally stable in aqueous systems

Ana Maria Barbosa Medina 25 April 2016 (has links)
Os ésteres de ftalato (PAEs) são compostos produzidos em grandes quantidades, amplamente utilizados industrialmente como agentes plastificantes. Seus resíduos são lixiviados pela água tornando-se poluentes orgânicos persistentes (POPs) no meio ambiente aquoso, além de apresentar características de interferência endócrina. O dietil ftalato (DEP) é frequentemente encontrado nas amostras ambientais, pois possui elevada solubilidade na água e pode ser gerado durante a degradação de outros PAEs. Assim, este trabalho teve como objetivo a degradação do dietil ftalato em meio aquoso por método eletroquímico utilizando um ânodo dimensionalmente estável (ADE) comercial representado como Ti/Ru0,3Ti0,7O2 em uma célula do tipo filtro-prensa. As eletrólises foram de 120 minutos contendo uma concentração inicial de 100,3 mg L-1 de DEP, pH inicial igual a 3, a temperatura em 25 °C e vazão em 250 mL min-1. Os experimentos foram feitos utilizando planejamento fatorial do tipo 32 com duas réplicas no ponto central, apresentando como variáveis independentes a densidade de corrente (10, 25 e 40 mA cm-2) e o logaritmo em base 10 da forca iônica do eletrólito suporte, NaCl e Na2SO4 (µ = 0,05, 0,15 e 0,5 mol L-1), com o intuito de estudar o efeito da densidade de corrente, concentração e natureza do eletrólito para determinar a melhor condição de degradação do dietil ftalato. O monitoramento da concentração do DEP foi feito com cromatografia líquida de alta eficiência (CLAE) e a mineralização foi acompanhada pelas análises de carbono orgânico total (COT). Foram obtidas maiores porcentagens de remoção e mineralização com uso das maiores densidades de corrente e na presença de altas concentrações de NaCl em comparação com Na2SO4. Dessa maneira, se obteve remoção de 63,2 % e mineralização de 63,9 % em solução 0,5 mol L-1 NaCl e densidade de corrente de 40 mA cm-2, enquanto que para Na2SO4 (µ = 0,5 mol L-1) e 40 mA cm-2 foi removido 51,3 % e mineralizado 53,0 % de DEP. O mecanismo de degradação de DEP foi determinado em meio de NaCl e Na2SO4, através de CLAE-MS nas condições citadas anteriormente, identificando-se os íons moleculares de m/z 149 e 177 em ambos eletrólitos, correspondentes ao anidrido ftálico protonado e ao aduto do anidrido ftálico com C(2)H(5)(+) respectivamente, íons característicos da fragmentação do DEP, além do íon m/z 239 em Na2SO4 correspondente ao dietil 3-hidroxiftalato. A degradação do DEP acontece através da cadeia alifática. / Phthalate esters (PAEs) are compounds produced in large amounts industrially widely used as plasticizers. Their waste are leached by water becoming persistent organic pollutants (POPs) in the aqueous environment, besides having endocrine disrupting characteristics. Diethyl phthalate (DEP) is frequently found in environmental samples, it has high solubility in water and can be generated during the degradation of other PAEs. This work studied the degradation of diethyl phthalate in aqueous media by electrochemical method using a commercial dimensionally stable anode (ADE) represented as Ti/Ru0,3Ti0,7O2 in a filter-press flow cell. The electrolysis were carried out during 120 minutes containing an initial concentration of 100.3 mg L-1 DEP, initial pH = 3, temperature at 25 °C and flow rate of 250 ml min-1. The experiments were performed using factorial design 32 with two replicas at the midpoint, with as independent variables the current density (10, 25 and 40 mA cm-2) and the logarithm base 10 of the ionic strength of the electrolyte, NaCl and Na2SO4 (µ = 0.05, 0.15 and 0.5 mol L-1), in order to study the effect of current density, concentration and nature of the electrolyte to determine the best diethyl phthalate degradation condition. The monitoring of DEP concentration was made by high-performance liquid chromatography (HPLC) and the mineralization was accompanied by total organic carbon (TOC) analysis. They obtained higher percentages of removal and mineralization with the use of higher current densities and in the presence of high concentrations of NaCl in comparison with Na2SO4. Thus, there was obtained the removal of 63.2 % and 63.9 % mineralization in 0.5 mol L-1 NaCl and current density of 40 mA cm-2, whereas for Na2SO4 (µ = 0.5 mol L-1) and 40 mA cm-2 was removed 51.3 % and 53.0% mineralized DEP. The DEP degradation mechanism was determined in NaCl and Na2SO4, by HPLC-MS under the conditions mentioned above, identifying the molecular ion of m/z 149 and 177 on both electrolytes, corresponding to protonated phthalic anhydride and an adduct of phthalic anhydride with C(2)H(5)(+), respectively, characteristic ions of DEP fragmentation, besides the ion m/z 239 over Na2SO4 corresponding to diethyl 3-hydroxyphthalate. The DEP degradation takes place through the aliphatic chain.

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