The research presented in this thesis investigated the functional morphology in root<br />systems in relation to their role in providing anchorage and stability for the plant. The<br />anchorage of different types of root systems was investigated as well as the influence of<br />several environmental factors on their development. The research presented in this study<br />was completed by carrying out a series of modelling, glasshouse and field experiments<br />using physical models and real plants.<br />Model experiments showed that solid shapes like bulbs are very well suited to resist<br />vertical upward forces, i.e. uprooting, and shed some light on the mechanism of<br />anchorage in bulbs. The results of this laboratory study showed that the concept of<br />optimal bulb shape for resisting uprooting is viable. Uprooting tests on real bulb plants<br />confirmed the theoretical predictions about it, and showed the importance of bulbs in<br />anchorage. This study also proved that the soil type is very important when considering<br />the anchorage of solid forms such as the bulbs.<br />A second model study showed that the simplest models of tap root-dominated root<br />systems increase their resistance to overturning with the third and second power of the<br />embedment depth in cohesionless and in cohesive soil respectively. Anchorage strength<br />of a root system dominated by a tap root will be maximised with minimum investment<br />in structural material if the rigid tap root is extended to the largest possible depth.<br />Glasshouse experiments investigated the effects of soil compaction and temperature,<br />two of the most important environmental factors, on the axial and lateral development<br />and growth of the root systems of two species of young pines. It was shown that the rate<br />of root axial development in both investigated species decreased with an increase in soil<br />compaction whereas the lateral proliferation of their roots systems was not significantly<br />affected by soil consistency. A temperature of around 15°C seemed to be optimal for the<br />root elongation rate since the increase in axial length of the roots of both species was<br />largest at this temperature.<br />The effect of mechanical stimulation as a factor in shaping the root systems of plants<br />was also investigated. Apart from the changes caused to the parts of the tree above<br />ground, unidirectional periodical flexing induced an increase in total root CSA and<br />larger biomass allocation to the roots parallel to the plane of flexing which, in turn,<br />resulted in a larger number of major lateral roots with larger CSA in the plane of<br />flexing.<br />Mechanical and morphological field studies on two Pinus species investigated the<br />anchorage of plate root systems and showed that lateral roots in older trees are not the<br />major source of root anchorage in either of the species; although in both species a<br />certain asymmetry in the distribution of major lateral root CSA was recorded, it was not<br />significantly correlated to the asymmetry in anchorage.

The objective of an Energy Control Center (ECC) is to ensure secure and economic operation of power system. The challenge to optimize power system operation, while maintaining system security and quality of power supply to customers, is increasing. Growing demand without matching expansion of generation and transmission facilities and more tightly interconnected power systems contribute to the increased complexity of system operation. Rising costs due to inflation and increased environmental concerns has made transmission, as well as generation systems to be operated closure to design limits, with smaller safety margins and hence greater exposure to unsatisfactory operating conditions following a disturbance. Investigations of recent blackouts indicate that the root cause of most of these major power system disturbances is voltage collapse. Information gathered and preliminary analysis, from the most recent blackout incident in North America on 14th August 2003, is pointing the finger on voltage instability due to some unexpected contingency. In this incident, reports indicate that approximately 50 million people were affected interruption from continuous supply for more than 15 hours. Most of the incidents are related to heavily stressed system where large amounts of real and reactive power are transported over long transmission lines while appropriate real and reactive power resources are not available to maintain normal system conditions. Hence, the problem of voltage stability and voltage collapse has become a major concern in power system planning and operation. Reliable operation of large scale electric power networks requires that system voltages and currents stay within design limits. Operation beyond those limits can lead to equipment failures and blackouts. In the last few decades, the problem of reactive power control for improving economy and security of power system operation has received much attention. Generally, the load bus voltages can be maintained within their permissible limits by reallocating reactive power generations in the system. This can be achieved by adjusting transformer taps, generator voltages, and switchable Ar sources. In addition, the system losses can be minimized via redistribution of reactive power in the system. Therefore, the problem of the reactive power dispatch can be optimized to improve the voltage profile and minimize the system losses as well. The Instability in power system could be relieved or at least minimized with the help of most recent developed devices called Flexible AC Transmission System (FACTS) controllers. The use of Flexible AC Transmission System (FACTS) controllers in power transmission system have led to many applications of these controllers not only to improve the stability of the existing power network resources but also provide operating flexibility to the power system. In the past, transmission systems were owned by regulated, vertically integrated utility companies. They have been designed and operated so that conditions in close proximity to security boundaries are not frequently encountered. However, in the new open access environment, operating conditions tend to be much closer to security boundaries, as transmission use is increasing in sudden and unpredictable directions. Transmission unbundling, coupled with other regulatory requirements, has made new transmission facility construction more difficult. In fact, there are numerous technical challenges emerging from the new market structure. There is an acute need for research work in the new market structure, especially in the areas of voltage security, reactive power support and congestion management. In the last few decades more attention was paid to optimal reactive power dispatch. Since the problem of reactive power optimization is non-linear in nature, nonlinear programming methods have been used to solve it. These methods work quite well for small power systems but may develop convergence problems as system size increases. Linear programming techniques with iterative schemes are certainly the most promising tools for solving these types of problems. The thesis presents efficient algorithms with different objectives for reactive power optimization. The approach adopted is an iterative scheme with successive power-flow analysis using decoupled technique, formulation and solution of the linear-programmingproblem with only upper-bound limits on the state variables. Further the thesispresents critical analysis of the three following objectives, Viz., •Minimization of the sum of the squares of the voltage deviations (Vdesired) •Minimization of sum of the squares of the voltage stability L indices (Vstability) •Minimization of real power losses (Ploss) Voltage stability problems normally occur in heavily stressed systems. While the disturbance leading to voltage collapse may be initiated by a variety of causes, the underlying problem is an inherent weakness in the power system. The factors contributing to voltage collapse are the generator reactive power /voltage control limits, load characteristics, characteristics of reactive compensation devices, and the action of the voltage control devices such as transformer On Load Tap Changers (OLTCs). Power system experiences abnormal operating conditions following a disturbance, and subsequently a reduction in the EHV level voltages at load centers will be reflected on the distribution system. The OLTCs of distribution transformers would restore distribution voltages. With each tap change operation, the MW and MVAR loading on the EHV lines would increase, thereby causing great voltage drops in EHV levels and increasing the losses. As a result, with each tap changing operation, the reactive output of generators throughout the system would increase gradually and the generators may hit their reactive power capability limits, causing voltage instability problems. Thus, the operation of certain OLTCs has a significant influence on voltage instability under some operating conditions. These transformers can be made manual to avoid possible voltage instability due to their operation during heavy load conditions. Tap blocking, based on local measurement of high voltage side of load tap changers, is a common practice of power utilities to prevent voltage collapse. The great advantage of this method is that it can be easily implemented, but does not guarantee voltage stability. So a proper approach for identification of critical OLTC s based on voltage stability criteria is essential to guide the operator in ECC, which has been proposed in this thesis. It discusses the effect of OLTCs with different objectives of reactive power dispatch and proposes a technique to identify critical OLTCs based on voltage stability criteria. The fast development of power electronics based on new and powerful semiconductor devices has led to innovative technologies, such as High Voltage DC transmission (HVDC) and Flexible AC Transmission System (FACTS), which can be applied in transmission and distribution systems. The technical and economicalBenefits of these technologies represent an alternative to the application in AC systems. Deregulation in the power industry and opening of the market for delivery of cheaper energy to the customers is creating additional requirements for the operation of power systems. HVDC and FACTS offer major advantages in meeting these requirements. .A method for co-ordinated optimum allocation of reactive power in AC/DC power systems by including FACTS controller UPFC, with an objective of minimization of the sum of the squares of the voltage deviations of all the load buses has been proposed in this thesis. The study results show that under contingency conditions, the presence of FACTS controllers has considerable impact on over all system voltage stability and also on power loss minimization.minimization of the sum of the squares of the voltage deviations of all the load buses has been proposed in this thesis. The study results show that under contingency conditions, the presence of FACTS controllers has considerable impact on over all system voltage stability and also on power loss minimization. As power systems grow in their size and interconnections, their complexity increases. For secure operation and control of power systems under normal and contingency conditions, it is essential to provide solutions in real time to the operator in ECC. For real time control of power systems, the conventional algorithmic software available in ECC are found to be inadequate as they are computationally very intensive and not organized to guide the operator during contingency conditions. Artificial Intelligence (AI) techniques such as, Expert systems, Neural Networks, Fuzzy systems are emerging decision support system tools which give fast, though approximate, but acceptable right solutions in real time as they mostly use symbolic processing with a minimum number of numeric computations. The solution thus obtained can be used as a guide by the operator in ECC for power system control. Optimum real and reactive power dispatch play an important role in the day-to-day operation of power systems. Existing conventional Optimal Power Flow (OPF) methods use all of the controls in solving the optimization problem. The operators can not move so many control devices within a reasonable time. In this context an algorithm using fuzzy-expert approach has been proposed in this thesis to curtail the number of control actions, in order to realize real time objectives in voltage/reactive power control. The technique is formulated using membership functions of linguistic variables such as voltage deviations at all the load buses and the voltage deviation sensitivity to control variables. Voltage deviations and controlling variables are translated into fuzzy set notations to formulate the relation between voltage deviations and controlling ability of controlling devices. Control variables considered are switchable VAR compensators, OLTC transformers and generator excitations. A fuzzy rule based system is formed to select the critical controllers, their movement direction and step size. Results show that the proposed approach is effective for improving voltage security to acceptable levels with fewer numbers of controllers. So, under emergency conditions the operator need not move all the controllers to different settings and the solution obtained is fast with significant speedups. Hence, the proposed method has the potential to be integrated for on-line implementation in energy management systems to achieve the goals of secure power system operation. In a deregulated electricity market, it may not be always possible to dispatch all of the contracted power transactions due to congestion of the transmission corridors. System operators try to manage congestion, which otherwise increases the cost of the electricity and also threatens the system security and stability. An approach for alleviation of network over loads in the day-to-day operation of power systems under deregulated environment is presented in this thesis. The control used for overload alleviation is real power generation rescheduling based on Relative Electrical Distance (RED) concept. The method estimates the relative location of load nodes with respect to the generator nodes. The contribution of each generator for a particular over loaded line is first identified , then based on RED concept the desired proportions of generations for the desired overload relieving is obtained, so that the system will have minimum transmission losses and more stability margins with respect to voltage profiles, bus angles and better transmission tariff. The results obtained reveal that the proposed method is not only effective for overload relieving but also reduces the system power loss and improves the voltage stability margin. The presented concepts are better suited for finding the utilization of resources generation/load and network by various players involved in the day-to-day operation of the system under normal and contingency conditions. This will help in finding the contribution by various players involved in the congestion management and the deviations can be used for proper tariff purposes. Suitable computer programs have been developed based on the algorithms presented in various chapters and thoroughly tested. Studies have been carried out on various equivalent systems of practical real life Indian power networks and also on some standard IEEE systems under simulated conditions. Results obtained on a modified IEEE 30 bus system, IEEE 39 bus New England system and four Indian power networks of EHV 24 bus real life equivalent power network, an equivalent of 36 bus EHV Indian western grid, Uttar Pradesh 96 bus AC/DC system and 205 Bus real life interconnected grid system of Indian southern region are presented for illustration purposes.

Voltage instability is a major concern in operation of power systems and it is well known that voltage instability and collapse have led to blackout or abnormally low voltages in a significant part of the power system. Consequently, tracking the proximity of the power system to an insecure voltage condition has become an important element of any protection and control scheme. The expected time until instability is a critical aspect. There are a few energy management systems including voltage stability analysis function in the real-time environment of control centres, these are based on assumptions (such as off-line models of the system loads) that may lead the system to an insecure operation and/or poor utilization of the resources. Voltage instability is driven by the load dynamics, and investigations have shown that load restoration due to the on-load tap changer (OLTC) action is the main cause of the voltage instability. However, the aggregate loads seen from bulk power delivery transformers are still the most uncertain power system components, due to the uncertainty of the participation of individual loads and shortcomings of the present approaches in the load modeling. In order to develop and implement a true on-line voltage stability analysis method, the on-line accurate modeling of the higher voltage (supply system) and the lower voltage level (aggregate load) based on the local measurements is required. In this research, using the changes in the load bus measured voltage and current, novel methods are developed to estimate the supply system equivalent and to identify load parameters. Random changes in the load voltage and current are processed to estimate the supply system Thevenin impedance and the composite load components are identified in a peeling process using the load bus data changes during a large disturbance in the system. The results are then used to anticipate a possible long-term voltage instability caused by the on-load tap changer operation following the disturbance. Work on the standard test system is provided to validate the proposed methods. The findings in this research are expected to provide a better understanding of the load dynamics role in the voltage stability, and improve the reliability and economy of the system operation by making it possible to decrease uncertainty in security margins and determine accurately the transfer limits.

Made available in DSpace on 2015-02-24T19:48:38Z (GMT). No. of bitstreams: 1 VladimirCM_ate_Cap2.pdf: 2326830 bytes, checksum: b58da6e64643f0b1b300b813b8340f81 (MD5) Previous issue date: 2004-11-30 / Companhia de Pesquisa de Recursos Minerais / This thesis aims to advance in the geological knowledge of the region comprising the Pianc?-Alto Br?gida (TPAB) and Alto paje? (TAP) terranes, in the Transversal Zone Domain (Borborema Province, NE Brazil), with the main objective of understanding the geodynamic evolution and the structural framework of these units. To reach this objective, and besides field work and interpretation of traditional aerial photographs, other tools were employed like of remote sensing products (Landsat 7 ETM+, aeroradiometrics, aeromagnetics and topographical images), lithogeochemical (whole rock) analyses and geochronological dating (U-Pb in zircon), besides integration with literature data. In the area, several precambrian geological units outcrop, represented in the TAP by the paleoproterozoic Serra Talhada and Afogados da Ingazeira complexes, Riacho Gravat? Complex (metavolcano-sedimentary sequence of Stenian-Tonian age) and Cariris Velhos orthogneisses (of Tonian age). The TPAB comprises the Santana do Garrote (lower unit) and Serra do Olho d'?gua (upper unit) formations of the Cachoeirinha Group (Neoproterozoic III), besides the Pianc? orthogneisses and Bom Jesus paragneisses; the latter correspond to an older (basement ?) block and a possible high grade equivalent of the Cachoeirinha Group (or Serid? Group ?), respectively. Several Brasiliano-age plutons occur in both terranes.The aeromagnetic data show the continuity, at depth, of the main shear zones mapped in the region. The Patos, Pernambuco, Boqueir?o dos Cochos, Serra do Caboclo, Afogados da Ingazeira/Jabitac? and Congo-Cruzeiro do Nordeste shear zones reach depths greater than to 6-16 km. The aeromagnetic signature of other shear zones, like the Juru one, suggests that these structures correspond to shallower crustal features. The satellite images (Landsat 7 ETM+) and aerogamaspectrometric images discriminate different geological units, contributing to the mapping of the structural framework of the region. The Serra do Caboclo Shear Zone was characterized as the boundary/suture between the TPAB and TAP. This structure is an outstanding, pervasive feature that separates contrasting geological units, such as the Neoproterozoic III Cachoeirinha Group in the TPAB and the Riacho Gravat? Complex and the Cariris Velhos metaplutonics, of Stenian-Tonian age, in the TAP. Occupying different blocks, these units are not found in authoctonous relations, like unconformities and intrusive contacts. Concerning the Cariris Velhos (ca. 1,0 Ga old) event is recorded by radiometric ages of the Riacho Gravat? Complex metavolcanics and intrusive augen and orthogneisses, all of them displaying geochemical affinities of arc or collisional settings. A structural signature of this event was not recorded in the region, possibly due to its low grade/low strain style, obliterated by the overprinting of younger, higher grade/high strain Brasiliano-age fabrics.The first tectonic event (D1) observed in the Cariris Velhos lithotypes presents contractional kinematics with transport to the NW. Neoproterozoic III geochronologic dates, obtained in late-D1 granitoids, imply a Brasiliano age (ca. 610-600 Ma) for this deformation event. The second tectonic event (D2) characterized in the region corresponds to the Brasiliano transcurrent kinematics of the outstanding shear zones and associated granitoid plutons. The geochronological (U-Pb in zircon) data obtained during this thesis also confirms the occurrence of the Cariris Velhos magmatic suite in the TAP, as well as the Neoproterozoic III age to the Cachoeirinha Group in the TPAB. The TAP (Riacho Gravat? Complex, augen and orthogneisses) is interpreted as a continental arc possibly accreted to a microcontinent during the Cariris Velhos (Stenian-Tonian) event. Later on, this terrane collided with the TPAB at the beginning of the Brasiliano orogeny (D1 contractional deformation), and both domins were reworked by the transcurrent shear deformation of the D2 event / A presente tese procurou avan?ar no conhecimento geol?gico da regi?o que abrange os terrenos Pianc?-Alto Br?gida (TPAB) e Alto paje? (TAP) , no Dom?nio da Zona Transversal (Prov?ncia Borborema, NE do Brasil), com o intuito principal de compreender a evolu??o geodin?mica e o condicionamento estrutural destas unidades. Para atingir este objetivo, al?m do trabalho de campo e da interpreta??o de fotografias a?reas tradicionais, foram utilizados outros produtos de sensoriamento remoto (imagens Landsat 7 ETM+, aeroradiom?tricas, aeromagn?ticas e topogr?ficas), an?lises litogeoqu?micas (rocha total) e data??es geocronol?gicas (U-Pb em zirc?o), al?m da integra??o com dados da literatura. Na regi?o afloram v?rias unidades geol?gicas precambrianas, representadas no T AP pelos complexos paleoproteroz?icos de Serra Talhada e Afogados da Ingazeira, Complexo Riacho Gravat? (seq??ncia metavulcanossedimentar de idade Esteniana-Toniana) e ortognaisses Cariris Velhos (Tonianos). No TPAB ocorrem as forma??es Santana do Garrote (unidade inferior) e Serra do Olho d'?gua (unidade superior) do Grupo Cachoeirinha (Neoproteroz?ico III), al?m dos ortognaisses de Pianc? e paragnaisses de Bom Jesus, estes dois ?ltimos podendo constituir um bloco mais antigo (embasamento ?) e um equivalente de alto grau do Grupo Cachoeirinha (ou Grupo Serid? ?), respectivamente. Em ambos os terrenos ainda ocorrem v?rios corpos degranit?ides brasilianos. Os dados aeromagn?ticos permitiram estimar a continuidade, em profundidade, das principais zonas de cisalhamento cartografadas na regi?o. As zonas de cisalhamento de Patos, Pernambuco, Boqueir?o dos Cochos, Serra do Caboclo, Afogados da Ingazeira/Jabitac? e Congo-Cruzeiro do Nordeste atingem profundidades . superiores a 6-16 km. A assinatura aeromagn?tica de outras zonas de cisalhamento, tais como a de Juru, sugere que tais estruturas correspondem a fei??es crustais mais rasas. As imagens de sat?lite (Landsat 7 ETM+) e aerogamaespectrom?tricas permitiram individualizar unidades geol?gicas distintas, bem como esbo?ar a trama estrutural da regi?o.A Zona de Cisalhamento Serra do Caboclo foi caracterizada como o limite/sutura entre o TPAB e TAP, tendo em vista ser uma estrutura marcante/penetrativa que separa unidades geol?gicas contrastantes, como o Grupo Cachoeirinha (Neoproteroz?ico III) no TPAB e o Complexo Riacho Gravat? (Esteniano-Toniano) e as metaplut?nicas Cariris Velhos, do TAP. Embora mais jovem, o Grupo Cachoeirinha n?o exibe contatos em n?o conformidade sobre o Complexo Riacho Gravat? ou ortognaisses Cariris Velhos, indicando que aquelas unidades estavam distanciadas quando da sua deposi??o. Com rela??o ao evento Cariris Velhos (ca. 1,0 Ga), a presen?a do mesmo ? indicada pelas metavulc?nicas do Complexo Riacho Gravat?, augen gnaisses e ortognaisses intrusivos, todos com afinidade geoqu?mica de contextos de arco ou colisional. Todavia, o registro estrutural associado a este evento n?o foi identificado, o que foi interpretado em fun??o de sua oblitera??o (constitu?am estruturas de baixo grau/baixo strain) pelos eventos subseq?entes. O primeiro evento tect?nico (01) observado nos litotipos de idade Cariris Velhos apresenta cinem?tica contracional com transporte para NW. Uma data??o do Neoproteroz?ico III, obtida em granit?ide tardi-D1, permite atribuir uma idade do in?cio do brasiliano para este eventodeformacional. O segundo evento (D2) caracterizado na regi?o corresponde ? tect?nica transcorrente Brasiliana, a qual ? materializada por marcantes zonas de cisalhamento e corpos gran?ticos associados. Os dados geocronol?gicos obtidos (U-Pb em zirc?o) confirmaram a presen?a do magmatismo Cariris Velhos no ?mbito do TAP, bem como a idade Neoproteroz?ica III para o Grupo Cachoeinha (TPAB) e para o evento tect?nico D1. O TAP (Complexo Riacho Gravat?, augen gnaisses e ortognaisses) deve constituir um arco continental (provavelmente acrescido a um microcontinente) formado durante o evento Cariris Velhos (Esteniano-Toniano). Este terreno colidiu com o TPAB no inicio da orog?nese brasiliana (deforma??o tangencial D1), sendo ambos os blocos afetados por retrabalhamento/cisalhamentos transcorrentes (evento D2) at? o final do Ciclo Brasiliano

The modern day power system is witnessing a tremendous change. There has been a rapid rise in the distributed generation, along with this the deregulation has resulted in a more complex system. The power demand is on a rise, the generation and trans-mission infrastructure hasn't yet adapted to this growing demand. The economic and operational constraints have forced the system to be operated close to its design limits, making the system vulnerable to disturbances and possible grid failure. This makes the study of voltage stability of the system important more than ever. Generally, voltage stability studies are carried on a single phase equivalent system assuming that the system is perfectly balanced. However, the three phase power system is not always in balanced state. There are a number of untransposed lines, single phase and double phase lines. This thesis deals with three phase voltage stability analysis, in particular the voltage stability index known as L-Index. The equivalent single phase analysis for voltage stability fails to work in case of any unbalance in the system or in presence of asymmetrical contingency. Moreover, as the system operators are giving importance to synchrophasor measurements, PMUs are being installed throughout the system. Hence, the three phase voltages can be obtained, making three phase analysis easier. To study the effect of unbalanced system on voltage stability a three phase L-Index based on traditional L-Index has been proposed. The proposed index takes into consideration the unbalance resulting due to untransposed transmission lines and unbalanced loads in the system. This index can handle any unbalance in the system and is much more realistic. To obtain bus voltages during unbalanced operation of the system a three phase decoupled Newton Raphson load ow was used. Reactive power distribution in a system can be altered using generators voltage set-ting, transformers OLTC settings and SVC settings. All these settings are usually in balanced mode i.e. all the phases have the same setting. Based on this reactive power optimization using LP technique on an equivalent single phase system is proposed. This method takes into account generator voltage settings, OLTC settings of transformers and SVC settings. The optimal settings so obtained are applied to corresponding three phase system. The effectiveness of the optimal settings during unbalanced scenario is studied. This method ensures better voltage pro les and decrease in power loss. Case studies of the proposed methods are carried on 12 bus and 24 bus EHV systems of southern Indian grid and a modified IEEE 30 bus system. Both balanced and unbalanced systems are studied and the results are compared.

This thesis deals with a power flow control in the electric power system. An overview of FACTS devices is introduced; their basic characteristics as well as examples of their application are discussed. A significant part of this thesis investigates phase shifting transformers (PST´s), which seem to be suitable for implementation in the transmission system of the Czech Republic. The PST´s are useful devices that control active power flows on cross-border lines and regulate unwanted and unexpected power flows. Basic types and characteristics of the PST´s are discussed. In chapter 7 is designed laboratory task that should validate the regulatory capabilities of the transformer PST. Designs of models of individual parts of this laboratory task are presented. In the last part of this thesis the regulation effect of the PST is validated in the GLF/AES program.

<p>Cilj ove doktorske disertacija&nbsp; bio je razvoj&nbsp; novih, osetljivih, selektivnih i ekonomski<br />isplativih&nbsp; voltametrijskih&nbsp; radnih&nbsp; elektroda&nbsp; za&nbsp; praćenje&nbsp; odabranih&nbsp; analita&nbsp; kako&nbsp; u<br />laboratorijskim tako i pri terenskim uslovima.&nbsp; Ispitivana je&nbsp; mogućnost primene&nbsp; ovih&nbsp; radnih&nbsp; elektroda&nbsp; primenom&nbsp; voltametrijskih&nbsp; metoda&nbsp; kako&nbsp; u&nbsp; model&nbsp; rastvorima&nbsp; tako&nbsp; i&nbsp; u&nbsp; pojedinim realnim sistemima. SW-ASV&nbsp; zasnovana&nbsp; na&nbsp; elektrodama&nbsp; od&nbsp; staklastog&nbsp; ugljenika&nbsp; povr&scaron;inski modifikovanim&nbsp; Bi-MWCNT&nbsp; i&nbsp; BiOCl-MWCNT&nbsp; je&nbsp; primenjena&nbsp; za&nbsp; određivanje&nbsp; jona&nbsp; Pb(II)&nbsp; i Cd(II)&nbsp; pri&nbsp; optimizovanim&nbsp; uslovima&nbsp; merenja.&nbsp; Određivanje&nbsp; ciljnih&nbsp; jona&nbsp; vr&scaron;eno&nbsp; je&nbsp; pri&nbsp; radnom potencijalu&nbsp; od&nbsp; -1,2&nbsp; V&nbsp; (izmeren&nbsp; u&nbsp; odnosu&nbsp; na&nbsp; zasićenu&nbsp; kalomelovu&nbsp; elektrodu)&nbsp; i&nbsp; vremenu<br />elektrodepozicije jona&nbsp; od 120 s. Sva merenja su izvr&scaron;ena u rastvoru acetatnog pufera čija je pH-vrednost iznosila&nbsp; 4,0. Primenjeni koncentracioni opseg ciljnih analita iznosio je&nbsp; od 5 do 50&nbsp; &mu;g&nbsp; dm ^-3 .&nbsp; Primenom&nbsp; ovog&nbsp; tipa&nbsp; elektrode&nbsp; dobijene&nbsp; su&nbsp; vrednosti&nbsp; granice&nbsp; detekcije&nbsp; za&nbsp; jone Pb(II) i Cd(II) 0,57&nbsp; &mu;g dm ^-3i 1,2 &mu;g dm^-3 , redom. Dobijena RSD iznosila je manje od 10% za oba&nbsp; jona.&nbsp; Ova&nbsp; metoda&nbsp; je&nbsp; primenjena&nbsp; i&nbsp; za&nbsp; određivanje&nbsp; ciljnih&nbsp; jona&nbsp; u&nbsp; realnom&nbsp; uzorku&nbsp; porne vode&nbsp; sedimenta&nbsp; a&nbsp; rezultati&nbsp; dobijeni&nbsp; optimizovanom&nbsp; voltametrijskom&nbsp; metodom&nbsp; su&nbsp; u&nbsp; dobroj saglasnosti sa rezultatima koji su dobijeni primenom komparativne GFAAS metode. Bizmut oksihlorid-vi&scaron;ezidne ugljenične nanocevi kompozitni materijal je primenjen za povr&scaron;insko&nbsp; modifikovanje&nbsp; elektrode&nbsp; od&nbsp; staklastog&nbsp; ugljenika&nbsp; za&nbsp; brzo&nbsp; i&nbsp; jednostavno voltametrijsko&nbsp; određivanje&nbsp; tragova&nbsp; Zn(II)-jona&nbsp; primenom&nbsp; SW-ASV&nbsp; metode.&nbsp; BiOClMWCNT/GCE je pokazala linearan analitički odgovor u&nbsp; osegu koncentracija od&nbsp; 2,50 do&nbsp; 80,0 &mu;g&nbsp; dm ^-3sa dobijenom vredno&scaron;ću GD 0,75 &mu;g&nbsp; dm^-3pri akumulacionom vremenu od&nbsp; 120 s&nbsp; i potencijalu&nbsp; elektrodepozicije&nbsp; -1,40&nbsp; V&nbsp; u&nbsp; odnosu&nbsp; na&nbsp; ZKE.&nbsp; Merenja&nbsp; su&nbsp; vr&scaron;ena&nbsp; u&nbsp; acetatnom puferu pH 4,5. Dobijena RSD iznosila je 4,8 %. Upoređene su performanse novodizajnirane BiOCl-MWCNT/GCE elektrode&nbsp; i&nbsp; tradicionalne elektrode na bazi bizmut filma (BiF/GCE), MWCNT/GCE,&nbsp; BiF-MWCNT/GCE&nbsp; i&nbsp; nemodifikovane&nbsp; GC&nbsp; elektrode.&nbsp; Novodizajnirana elektroda je primenjena za&nbsp; detekciju&nbsp; i određivanje&nbsp; Zn(II)-jona&nbsp; u realnim&nbsp; uzorcima kao &scaron;to su<br />dijetetski&nbsp; suplement&nbsp; i&nbsp; pekarski&nbsp; kvasac.&nbsp; Dobijeni&nbsp; rezultati&nbsp; su&nbsp; uporedivi&nbsp; sa&nbsp; deklarisanom vredno&scaron;ću&nbsp; u&nbsp; slučaju&nbsp; dijetetskog&nbsp; suplementa&nbsp; a&nbsp; u&nbsp; slučaju&nbsp; pekarskog&nbsp; kvasca&nbsp; sa&nbsp; rezultatima dobijenih komparativnom FAAS .<br />Elektroda od ugljenične paste je povr&scaron;inski modifikovana pripremljenim kompozitom<br />koji je&nbsp; izgrađen od vi&scaron;ezidnih ugljeničnih nanocevi i čestica&nbsp; Sb₂O_3.&nbsp; Kompozitni&nbsp; materijal&nbsp; je okarakterisan&nbsp; primenom&nbsp; TEM,&nbsp; EDS&nbsp; i&nbsp; XRD&nbsp; mernih&nbsp; tehnika.&nbsp; Sb₂O₃-MWCNT/CPE&nbsp; je okarakterisana primenom ciklične voltametrije a merenja su vr&scaron;ena u rastvoru hlorovodonične kiseline&nbsp; (pH&nbsp; 2,0).&nbsp; Primenom&nbsp; SW-ASV&nbsp; metode&nbsp; ova&nbsp; radna&nbsp; elektroda&nbsp; je&nbsp; upotrebljena&nbsp; za određivanje&nbsp; jona Pb(II) i Cd(II)&nbsp; u&nbsp; koncentracionom opsegu 2,0-40,0&nbsp; &mu;g&nbsp; dm&nbsp; ^-3za&nbsp; Pb(II)-jon&nbsp; i 2,0-40,0&nbsp; &mu;g&nbsp; dm ^-3 za&nbsp; Cd(II)-jon&nbsp; pri&nbsp; čemu&nbsp; su&nbsp; dobijene&nbsp; dobre&nbsp; linearne&nbsp; zavisnosti&nbsp; za&nbsp; oba&nbsp; ciljna jona.&nbsp; Optimalna&nbsp; procedura&nbsp; uključuje&nbsp; primenu&nbsp; Sb2O3-MWCNT/CPE&nbsp; u&nbsp; 0,01&nbsp; mol dm ^-3<br />hlorovodoničnoj kiselini uz vreme elektrodepozicije jona iz rastvora od 120&nbsp; s&nbsp; na&nbsp; potencijaluod&nbsp; -1,2&nbsp; V,&nbsp; pri&nbsp; čemu&nbsp; su&nbsp; dobijene&nbsp; vrednosti&nbsp; za&nbsp; GD&nbsp; 1,1&nbsp; &mu;g&nbsp; dm ^-3 Cd(II)&nbsp; i&nbsp; 1,6&nbsp; &mu;g&nbsp; dm ^-3 Pb(II). Optimizovana&nbsp; metoda&nbsp; zasnovana&nbsp; na&nbsp; ovom&nbsp; tipu&nbsp; voltametrijskog&nbsp; senzora&nbsp; je&nbsp; uspe&scaron;no primenjena&nbsp; za&nbsp; određivanje&nbsp; jona&nbsp; Cd(II)&nbsp; u&nbsp; obogaćenom&nbsp; uzorku&nbsp; česmenske&nbsp; vode,&nbsp; gde&nbsp; su&nbsp; se dobijene vrednosti u&nbsp; saglasnosti sa očekivanom. Elektroda od ugljenične paste povr&scaron;inski je&nbsp; modifikovana primenom&nbsp; Sb₂O₃-MWCNT nanokompozitnog&nbsp; materijala&nbsp; i&nbsp; primenjena&nbsp; za&nbsp; direktno&nbsp; voltametrijsko&nbsp; određivanje imidakloprida&nbsp; u&nbsp; model&nbsp; rastvorima.&nbsp; U&nbsp; cilju&nbsp; postizanja&nbsp; &scaron;to&nbsp; boljih&nbsp; analitičkih&nbsp; performansi optimizovani su eksperimentalni uslovi merenja kao &scaron;to su pH-vrednost rastvora pomoćnog elektrolita&nbsp; i&nbsp; kondicioniranje&nbsp; povr&scaron;ine&nbsp; voltametrijskog&nbsp; senzora.&nbsp; Kao&nbsp; optimalna&nbsp; pH-vrednost pomoćnog elektolita (Britton-Robinsonovog pufera) odabrana je pH 7,0, a ponavljanje ciklusa cikliranja najmanje 4 puta povoljno utiče na stabilnost&nbsp; voltametrijskih signala. Optimizovana metoda primenjena je za SW direktno katodno određivanje imidakloprida u koncentracionom intervalu od 1,41 do 32,77 &mu;g cm ^-3 uz dobijeni korelacioni faktor od 0,9995. Na osnovu dobijenih rezultata može se zaključiti da su razvijene analitičke metode pre svega&nbsp; osetljive,&nbsp; selektivne,&nbsp; reproduktivne&nbsp; i&nbsp;&nbsp; jednostavne&nbsp; &scaron;to&nbsp; omogućava&nbsp; njihovu&nbsp; primenu&nbsp; za veliki broj uzoraka.&nbsp; Merenjima u model i realnim rastvorima dokazana je mogućnost njihove primene&nbsp; u&nbsp;&nbsp; komplikovanim&nbsp; matriksima,&nbsp; pri&nbsp; različitim&nbsp; pH&nbsp; vredostima&nbsp; pri&nbsp; čemu&nbsp; su&nbsp; dobijeni<br />rezultati koji su u saglasnosti sa rezultatima primenjenih komparativnih metoda. Naravno, za dobijanje&nbsp; reprezentativnih&nbsp; rezultata&nbsp; neohodno&nbsp; je&nbsp; izvr&scaron;iti&nbsp; optimizaciju&nbsp; uslova&nbsp; merenja&nbsp; &scaron;to podrazumeva sam odabir supstrat-elektrode, odabir povr&scaron;inskog modifikatora i optimizaciju eksperimentalnih uslova merenja.</p> / <p>The&nbsp; aim of this&nbsp; Ph.D. thesis&nbsp; was the development of new, sensitive, selective and economically&nbsp; viable&nbsp; voltametric&nbsp; working&nbsp; electrode&nbsp; for&nbsp; continuous&nbsp; monitoring&nbsp; of&nbsp; different target&nbsp; analytes.&nbsp; The&nbsp; use&nbsp; of&nbsp; these&nbsp; advantaged&nbsp; working&nbsp; electrodes&nbsp; was&nbsp; investigated&nbsp; using voltametric methods both in model solutions and in certain real systems.SW-ASV&nbsp; based on glassy carbon&nbsp; electrode surface modified with&nbsp; Bi- MWCNT and BiOCl-MWCNT&nbsp; were&nbsp; applied&nbsp; for&nbsp; determination&nbsp; of&nbsp; Pb(II)&nbsp; and&nbsp; Cd(II)&nbsp; ions.&nbsp; Voltametric determination&nbsp; of&nbsp; Pb(II)&nbsp; and&nbsp; Cd(II)&nbsp; ions&nbsp; was&nbsp; performed&nbsp; at&nbsp; working&nbsp; potential&nbsp; of&nbsp; -1.2&nbsp; V (measured against the saturated calomel electrode) and time of electrodeposition of 120 s. All measurements were performed in acetate buffer solution pH 4.0. Concentration range of targetanalites were&nbsp; 5-50 &mu;g&nbsp; dm -3 . Using this type of electrode,&nbsp; obtained&nbsp; detection limits for&nbsp; Pb(II) and Cd(II) ions&nbsp; were&nbsp; 0.57&nbsp; &mu;g&nbsp; dm -3 and 1.2&nbsp; &mu;g&nbsp; dm -3 , respectively, with RSD lower than 10%.This&nbsp; method&nbsp; was&nbsp; applied&nbsp; for&nbsp; target&nbsp; ions&nbsp; determination&nbsp; in&nbsp; sediment&nbsp; pore&nbsp; water&nbsp; sample,&nbsp; and obtained results are comparable with those who are obtained using GFAAS method. Bismuth oxychloride-multiwalled carbon nanotubes composite material was applied for&nbsp; surface&nbsp; modification&nbsp; of&nbsp; the&nbsp; glass-carbon&nbsp; electrode&nbsp; for&nbsp; quick&nbsp; and&nbsp; simple&nbsp; voltametric determination&nbsp; of&nbsp; Zn(II)&nbsp; ions&nbsp; using&nbsp; the&nbsp; SW-ASV&nbsp; method.&nbsp; BiOCl-MWCNT/GCE&nbsp; showed&nbsp; a linear&nbsp; analytical&nbsp; response&nbsp; in&nbsp; a&nbsp;&nbsp; concentration&nbsp; from&nbsp; 2.50&nbsp; to&nbsp; 80.0&nbsp; &mu;g&nbsp; dm -3 with&nbsp; a&nbsp; value&nbsp; of detection limit 0.75 &mu;g dm -3 at a acumulation time of 120 s and an electrodeposition potential of&nbsp; -1.40 V vs. saturated&nbsp; calomel electrode.&nbsp; Measurements were carried out in acetate buffer pH 4.5. The obtained&nbsp; value of the RSD&nbsp; was&nbsp; 4.8%. The performance of the newly designed BiOCl-MWCNT/GCE&nbsp; electrode,&nbsp; traditional&nbsp; bismuth-based&nbsp; electrode&nbsp; (BiF/GCE), MWCNT/GCE,&nbsp; BiF-MWCNT/GCE&nbsp; and&nbsp; unmodified&nbsp; GC&nbsp; electrodes&nbsp; were&nbsp; compared.&nbsp; The applied electrode shows very good electroanalytic properties when determining this target ion. Obtained results are in good agreement with declared value in case of dietetic suplement, and in the brewer&rsquo;s yeast sample results were comparable with FAAS results. Carbon&nbsp; paste&nbsp; electrode&nbsp; surface&nbsp; modified&nbsp; with&nbsp; new&nbsp; composite&nbsp; material&nbsp; based&nbsp; on multiwalled carbon nanotubes and&nbsp; Sb2O3&nbsp; particles. The composite is characterized by TEM, EDS and&nbsp; XRD measurment. Sb2O3- MWCNT/CPE was characterized by cyclic voltammetry and measurements were carried out in a&nbsp; hydrochloric acid&nbsp; solution&nbsp; (pH 2.0). Using the SWASV&nbsp; method,&nbsp; this&nbsp; working&nbsp; electrode&nbsp; was&nbsp; used&nbsp; to&nbsp; determine&nbsp; Pb(II),&nbsp; Cd(II)&nbsp; ions&nbsp; in&nbsp; the concentration range&nbsp; from&nbsp; 2.0&nbsp; to 40.0&nbsp; &mu;g dm -3 for Pb(II) and 2.0-40.0&nbsp; &mu;g dm -3 for Cd(II) ions. Newly&nbsp; designed&nbsp; sensor&nbsp; showed&nbsp; good&nbsp; linear&nbsp; dependences&nbsp; for&nbsp; both&nbsp; target&nbsp; ions.&nbsp; The&nbsp; most optimal&nbsp; procedure&nbsp; involving&nbsp; application&nbsp; of&nbsp; Sb2O3-MWCNT/CPE&nbsp; in&nbsp;&nbsp; .01&nbsp; mol&nbsp; dm -3 hydrochloric&nbsp; acid,&nbsp; with&nbsp; electroposition&nbsp; time&nbsp; of&nbsp; target&nbsp; ions&nbsp; 120&nbsp; s&nbsp; at&nbsp; a&nbsp; electrodeposition potential&nbsp; of&nbsp; -1.2&nbsp; V.&nbsp; Obtained&nbsp;&nbsp; values&nbsp; of&nbsp;&nbsp;&nbsp; LOD&nbsp; 1,1&nbsp; &mu;g&nbsp; dm -3 for&nbsp; Cd(II)&nbsp; and&nbsp; for&nbsp; 1,6&nbsp; &mu;g&nbsp; dm -3 Pb(II)&nbsp; ions.&nbsp; An&nbsp; optimized&nbsp; method&nbsp; based&nbsp; on&nbsp; this&nbsp; type&nbsp; of&nbsp; voltametric&nbsp; sensor&nbsp; has&nbsp; been successfully&nbsp; applied&nbsp; for&nbsp; determination&nbsp; of&nbsp; Cd(II)&nbsp; ion&nbsp; in&nbsp; a&nbsp; spiked&nbsp; tap&nbsp; water&nbsp; sample.&nbsp; Results obtained during this measurment were in tune with expected results. CPE&nbsp; was&nbsp; surface&nbsp; modified&nbsp; using&nbsp; Sb2O3-MWCNT&nbsp; nanocomposite&nbsp; material&nbsp; and tested&nbsp; for&nbsp; direct&nbsp; voltametric&nbsp; determination&nbsp; of&nbsp; imidacloprid&nbsp; in&nbsp; model&nbsp; solutions.&nbsp; In&nbsp; order&nbsp; to achieve the best analytical performance, experimental conditions of measurement such as the pH value of the supporting electrolyte and conditioning of the voltametric sensor surface havebeen&nbsp; optimized.&nbsp; As&nbsp; an&nbsp; optimum&nbsp; pH&nbsp; value&nbsp; of&nbsp; the&nbsp; supporting&nbsp; electrolyte&nbsp; (Britton-Robinson buffer), a pH 7.0 was selected, and the repeating cycles of the cycling process at least 4 times favorably&nbsp; influenced&nbsp; the&nbsp; stability&nbsp; of&nbsp; the&nbsp; voltametric&nbsp; signals.&nbsp; The&nbsp; optimized&nbsp; method&nbsp; was applied for the SW direct cathodic determination&nbsp; of&nbsp; imidacloprid in the concentration range from 1.41 to 32.77 &mu;g cm -3&nbsp; with obtained correlation factor of 0.9995. Based on results it can be concluded that developed analytical methods are sensitive, selective, reproducibile and simple, which can enable their application for various number of samples. Measurements in the model and real solutions have demonstrated the possibility of their&nbsp; application&nbsp; in&nbsp; complicated&nbsp; matrices,&nbsp; at&nbsp; different&nbsp; pH,&nbsp; whereby&nbsp; obtained&nbsp; results&nbsp; are&nbsp; in accordance&nbsp; with&nbsp; the&nbsp; results&nbsp; of&nbsp; the&nbsp; applied&nbsp; comparative&nbsp; methods.&nbsp; For&nbsp; obtainig&nbsp; of representative&nbsp; results&nbsp; it&nbsp; is&nbsp; necessary&nbsp; to&nbsp; optimize&nbsp; conditions&nbsp; of&nbsp; measurment&nbsp; which&nbsp; include: selection of substrat electrode, surface modifier and optimization of experimental condition.</p>

No description available.

近年，IoTに基づく「つながる工場」に関する技術開発が着目され，日本の次世代の製造業を支えるために，新しい研究開発が求められている．特に機械加工の現場では，異常検知や適応制御のために加工現象を精確かつリアルタイムにモニタできる技術が必要とされている．そこで，マシニングセンタなどの工作機械において，回転工具の加工中に多チャンネルで各種の物理量を切削点近傍にてモニタ可能な無線多機能ホルダを開発し，様々な工具，加工方法を対象にその有効性を示した． / Currently, a smart monitoring technology has been attracting particular attention in the factory automation fields regarding the Internet of things (IoT). Particularly in the machining site, the technology of monitoring the processing phenomenon in precision and real-time is required for abnormality detection or adaptive control. Then, we developed a novel tool holder equipped with a wireless communication function to monitor the tool temperature and vibrating accelerations near the cutting point during a tool rotating operation, and we showed effectiveness for various tools and processing method. / 博士(工学) / Doctor of Philosophy in Engineering / 同志社大学 / Doshisha University

Il apparaît au grand jour que de nombreuses substances telles que les perturbateurs endocriniens sont introduites quotidiennement dans l’environnement. Ces molécules organiques bien souvent d’origine anthropique peuvent être employées dans d’innombrables circonstances : pharmaceutique, médecine, agriculture, cosmétique, agroalimentaire pour citer quelques exemples. Parmi ce large panel de composés, se trouvent les hormones stéroïdiennes. Un certain nombre de maladies et de modifications aussi bien comportementales que physiologiques tant chez l’humain que sur la faune aquatique sont attribuées à l’usage et aux rejets chroniques de ces perturbateurs endocriniens. Il est donc indispensable de développer une approche portée sur la prévention et l’étude des niveaux de contamination selon un seul maître-mot : précaution. Dans ce contexte, ce projet de doctorat visait à développer de nouvelles méthodes de détection des hormones stéroïdiennes à niveau ultra-trace dans diverses matrices environnementales. La sélection des composés ciblés dans ce projet s’est basée sur la nouvelle liste de perturbateurs endocriniens prioritaires de l’agence de protection de l’environnement des États-Unis (US EPA), récemment élargie à d’autres classes de substances dont le bisphénol A. Les méthodes analytiques ont été développées non seulement dans l’eau du robinet (EPA 539), mais également dans d’autres matrices plus complexes (eaux de surface, eaux usées). Commune à l’ensemble des procédures testées, la phase de validation analytique a permis de vérifier la conformité avec les exigences de performance de l’EPA. La première méthode mise au point repose sur une pré-concentration rapide de l’échantillon par extraction sur phase solide en ligne (on-line SPE) couplée à la chromatographie liquide à ultra-haute performance (UHPLC) et à la spectrométrie de masse en tandem (MS/MS). La méthode validée présente de nombreux avantages—reproductibilité, automatisation, temps d’analyse minimal, logistique réduite et surtout des limites de détection de 0,10 ng·L-1 à 7,5 ng·L-1 selon les différentes matrices étudiées. Cette méthode apparaît particulièrement adaptée pour la détection des hormones dans les eaux usées, en lien avec les plus fortes concentrations attendues. Cependant, il est apparu pertinent d’améliorer encore la sensibilité des méthodes dans certains contextes, notamment dans le cadre des iv analyses d’eau de surface, compte tenu des critères de qualité applicables. La principale modification fut apportée au niveau de l’extraction et de la purification des échantillons. Amendée à la faveur des différentes matrices, l’étape d’extraction par SPE hors-ligne automatisée (off-line SPE) a permis d’atteindre des limites de détection adéquates variant de 0,010 ng·L-1 à 6,0 ng·L-1 dépendamment de la matrice et du composé. Un aspect original de cette étude a consisté à étudier de façon plus systématique les facteurs de robustesse de la méthode lorsque soumise à certaines variations, tant au niveau de l’analyse instrumentale (phases mobiles, volume d’injection) que des protocoles (emploi de différents agents de conservation, par exemple). L’analyse de la phase dissoute ne saurait être suffisante pour comprendre le devenir environnemental des perturbateurs endocriniens dans les milieux aquatiques, notamment leur distribution. Dans cette optique, la phase particulaire en suspension dans la colonne d’eau (SPM) fut également étudiée après optimisation et validation de la méthode d’extraction. Les limites de détection obtenues étaient comprises entre 0,10 ng/g et 3,0 ng/g, un degré de performance adéquat au regard des teneurs attendues dans l’environnement. De telles méthodes ne trouveraient pas de fondement si elles n’étaient pas employées à l’analyse d’échantillons réels. C’est pourquoi, pour chaque méthode développée, une série d’échantillons d’eau a été analysée pour toutes les matrices étudiées. La quantification des hormones stéroïdiennes a permis de rendre compte des niveaux de concentrations retrouvés dans l’environnement. Une étude saisonnière d’un cours d’eau a également été réalisée durant quatre saisons (hiver, printemps, été et automne) afin d’évaluer les éventuelles variations saisonnières en termes d’occurrence et de concentration. / It is now admitted that many substances such as endocrine disruptors are released daily into the environment. This process can be of natural origin but is predominantly linked to human activity. Endocrine disruptors originate from numerous fields: medicine, agriculture, cosmetics, and the food industry, to name a few. Steroid hormones belong to this wide array of compounds. A significant number of human diseases and behavioral and physiological changes in both humans and aquatic life have been attributed to the use and chronic release of these endocrine disruptors. The effects of such a cocktail of substances are difficult to understand and evaluate. To date, the synergistic mechanisms or the potential cumulative effects are not well known. It remains essential to develop an approach focused on the prevention and the study of contamination levels with one key word in mind: precaution. In this context and aiming to detect steroid hormones in tap water, surface water and wastewater at trace levels, new analytical methods have been developed within the framework of this project. The first method developed is based on high performance liquid chromatography (HPLC) coupled with tandem mass spectrometry (MS / MS). LC-MS/MS hyphenation involved using an electrospray ionization source at atmospheric pressure with heating element (H-ESI). Pre-concentration and purification of the samples were executed by on-line solid phase extraction (on-line SPE). The validated method presents several advantages: reproducibility, automation, minimum analysis time, reduced logistics and above all, detection limits ranging from 0.10 ng·L-1 to 7.5 ng·L-1 considering the different matrices studied. The second approach proposed herein is based on the development of an analysis method allowing lower detection limits compared to the previous workflow. The same detection method was used, but a modification was made to the sample extraction and purification. Allowing for greater pre-concentration than online SPE, manual SPE (off-line SPE) was used in this method. Depending on the particular matrix, the extraction step allowed to reach adequate detection limits for the analysis of environmental aqueous samples: 0.010 ng·L-1 up vi to 6.0 ng·L-1 from the matrix-free sample to the most complex matrices. The use of an automated system also made it possible to make the extraction step robust and reproducible. The analysis of the dissolved phase of water samples cannot be sufficient to understand and comprehensively assess the contamination of aquatic environments. The particulate phase in suspension in the water column (SPM) was also studied. The extraction method was optimized and validated. Coupled with the previous method of analysis, it was possible to quantify the steroid hormones attached to suspended materials. The obtained detection limits ranged from 0.10 ng/g to 3.0 ng/g dry weight. For each developed method, dissolved phase samples were analyzed for all the studied matrices (tap water, surface water and wastewater). Quantification of steroid hormones allowed the comprehension of concentration levels found in the environment under usual discharge conditions in multiples matrices. A seasonal study of a watercourse was also carried out during the winter, spring, summer and fall seasons to observe possible seasonal variations in terms of occurrence and concentration.