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Production of Mountain Whitefish (Prosopium williamsoni) in Altered and Unaltered Reaches of Two Intermountain Streams in Their Alluvial Flood PlainsOttenbacher, Michael J. 01 May 1980 (has links)
Estimates of production and related parameters (growth rate, density, standing crop) were made for populations of mountain whitefish in altered and "unaltered" areas of the Glacksmith Fork and Logan River, UtJh from spring 1975 through summer 1976. Capture records of marked whitefish were also analyzed to describe fish movement and check on assumptions implicit in the population estimator.
Mean weights and instantaneous growth rates of whitefish were similar at all sites for comparable size/age groups. Among sites, differences in production per sampling interval and annual production were due mainly to differences in standing crop and/or age structure.
Estimates of mountain whitefish density varied by site and season and ranged from 0 to 3,467 fish/ha, with the highest densities occurring during the fall and winter (spawning season) and the lowest during the summer when streamflows were low. Estimates of standing crops of whitefish followed a pattern similar to density. In the sites where fish remained during the summer most production occurred during the spring and summer.
A bulldozed reach of the Logan River (including an "unstable" section) had the highest annual production of mountain whitefish (51.85 kg/ha/yr)--almost double the annual production for the same reach when the unstable section was not included (31.85 kg/ha/yr). The highest annual production of whitefish in sites in the Blacksmith Fork River (51.23 kg/ha/yr) occurred in a reach that had been recently dredged but still contained a riffle and pool structure. Annual production of whitefish was low in a recently bulldozed reach (5.47 kg/ha/yr) and an old bulldozed reach (10.08 kg/ha/yr) of the Blacksmith Fork River where suitable habitat (pools and glides) was lacking, especially during the summer months.
Mountain whitefish remained or returned to reaches after channel alterations as long as water depth remained sufficient.
This study illustrated the necessity of frequent sampling when attempting to evaluate the effects of perturbations on fish populations or in production studies in general.
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Analyse reaktiver Toxizitätspotentiale organischer Elektrophile im Chemoassay mit 4-NitrothiophenolHiltrop, Rebecca 05 February 2016 (has links) (PDF)
Zur Bestimmung der toxizitätsrelevanten Thiolreaktivität wurde ein Chemoassay mit dem Modellnukleophil 4-Nitrothiophenol (NBT) entwickelt. Es wurden die Reaktionsgeschwindigkeitskonstanten kNBT für insgesamt 145 Verbindungen aus verschiedenen Stoffklassen bestimmt. Ein Modell zur Berücksichtigung der Flüchtigkeit der Elektrophile bei der Berechnung von kNBT wurde entwickelt. Außerdem wurde der Einfluss des pH-Werts auf die Thiolreaktivität unter reaktionsmechanistischen Gesichtspunkten diskutiert. Die NBT-Reaktivität wurde mit der Reaktivität gegenüber anderen toxizitätsrelevanten Nukleophilen verglichen. Zur Einordnung der Thiolreaktivität in den toxikologischen Zusammenhang wurden die Korrelationen zwischen kNBT und ausgewählten toxikologischen Endpunkten betrachtet. Am Beispiel der aquatischen Toxizität im Bioassay mit Tetrahymena pyriformis konnten stoffklassenspezifische Modelle zur Beschreibung der absoluten Toxizität log EC50 und der Toxizitätserhöhung log Te mit guter bis sehr guter Vorhersagekraft abgeleitet werden.
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Développement de méthodes analytiques pour la caractérisaton de lots industriels du nitroxyde SG1 / Development of analytical methods for the characterization of industrial batches of SG1-NitroxideMarchal, Cathie 29 November 2013 (has links)
Ce travail de thèse s’inscrit dans un contexte industriel. Il consiste en la caractérisation de lots bruts de SG1 : le N-tert-butyl-N- (1-diethylphosphono-2,2-dimethylpropyl)-N-oxyle. La spécificité de cette espèce est son caractère radicalaire stable. La première partie de ce travail consistait à développer une méthode d’analyse, facilement applicable en laboratoire d’analyse de contrôle sur site industriel pour la caractérisation de la pureté en SG1 dans des lots synthétisés. La méthode choisie a été développée par chromatographie liquide haute performance (HPLC). Pour ce faire, un étalon de SG1 a été préparé par purification de SG1 brut industriel en utilisant la technique séparative chromatographique de partage centrifuge (CPC). L’identification des impuretés suspectées majoritaires dans les lots de SG1 bruts a ensuite été réalisée par spectroscopie RMN ou par l’étude des fragments obtenus par spectrométrie de masse en tandem par ionisation electrospray. A l’aide de ces techniques, quinze impuretés majori- taires ont été identifiées. Des méthodes de quantification ont ensuite été développées pour douze de ces impuretés par diverses techniques analytiques chromatographiques : par HPLC-UV, HPLC-MS ou GC-MS ou par des techniques spectroscopiques Infra-Rouge ou encore par conductimétrie. / This PhD study has been carried out within an industrial context. It deals with the characterization of industrial batches of N-tert-butyl-N- (1-diethylphosphono-2,2-dimethylpropyl)-N-oxyle also called SG1. The distinctive feature of this molecule lies in its specific stability which is uncommon for radical species. The first part of this study consists in developping an analytical method, easy to implement in a QC laboratory for the determination of SG1 purity. The chosen analytical method has been developped by High Performances Liquid Chromatography (HPLC). This method requires the use of a standard sample of SG1, which has been obtained after purification of industrial batches of SG1 by the use of an innovative separative technology, the Centrifugal Partition Chromatography (CPC). The identification of the impurities, suspected as the major impurities in the industrial batches of SG1, has been carried out by NMR spectroscopy or by the study of their fragmentation observed by Tandem Mass Spectrometry – Electrospray Ionization. The use of these techniques enabled the identification of fifteen major impurities. Quantification methods by various techniques (HPLC-UV, HPLC-MS, GC-MS, other direct spectroscopic techniques like Infra-Red or other types of techniques like conductimetry) have been developped for twelve impurities.
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Autoriser pour interdire : la fabrique des savoirs sur les molécules et leurs risques dans le règlement européen REACH / Authorized Prohibitions : governing toxic chemicals and their risks with new forms of regulatory knowledge in the european REACH regulationBoullier, Henri 08 January 2016 (has links)
Comment réglementer des substances chimiques malgré des données anciennes, incomplètes, mais surtout inégalement partagées? Depuis l’adoption du Toxic Substances Control Act aux États-Unis en 1976, les asymétries d’information et la multiplication des utilisations des substances chimiques industrielles semblaient avoir rendu leur contrôle impossible. À ce problème longtemps insoluble, le règlement européen REACH, adopté en 2006, propose une réponse originale : la procédure d’autorisation. La thèse rend compte de la manière dont l’autorisation bouleverse la manière d’« interdire » malgré les asymétries d’information. Cette procédure donne désormais aux autorités publiques la possibilité d’interdire des « substances » sur la base de leur classification, tandis que certains « usages » de ces molécules peuvent ensuite être autorisés sur la base de demandes individuelles formulées par des entreprises. Pour continuer à les employer, ces entreprises mettent alors en circulation des données toxicologiques, d’exposition et surtout des évaluations socio-économiques jamais produites jusque-là. Si l’autorisation hérite d’une partie des dispositifs réglementaires précédents, où les activités réglementaires passent par la production de listes de substances chimiques, elle reconfigure surtout les rapports entre les autorités publiques et les entreprises, modifie les objets sur lesquels elles ont prise et transforme les manières d’élaborer les savoirs réglementaires qui appuient la prise de décision. / How can toxic chemicals be regulated with limited and incomplete data on their properties ? Since the Toxic Substances Control Act was adopted in the United States in 1976, information asymmetries and the multiplication of specific applications for chemicals had apparently made their control almost impossible. With the authorisation procedure, the european regulation on the registration, evaluation and authorisation of chemicals (REACH), adopted in 2006, introduces a novel way of controlling the most toxic chemicals. The dissertation shows how such a procedure sets new standards in regulatory control in spite of information asymmetries between regulators and firms. The authorisation procedure renders public authorities able to ban « substances » based on their hazards while some « uses » of these chemicals can be maintained on the market on the basis of invidual applications submitted by firms. In order have such applications accepted, firms provide public authorities with new toxicological and exposure data for very specific uses, and socio-economic analyses that had never been produced before. Although REACH is based on existing regulatory tools, the autorisation procedure profoundly modifies the relationship between regulators and firms, modifies the objects of regulation and transforms the ways in which regulatory knowledge for decision making is produced.
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Analýza požadavků na skladování nebezpečných látek v ČR pro mezinárodního poskytovatele logistických služeb / Processes of warehousing of chemicals of the lead logistics provider in the Czech RepublicPotančoková, Petra January 2014 (has links)
This thesis is focused on processes of warehousing of chemicals of the lead logistics provider in the Czech Republic. The aim of this thesis is to analyse legislative and safety requirements for warehousing of chemicals in the Czech Republic. An audit, which determines the correctness of warehousing, makes a suggestion and gives advice not only on the warehouse equipment but also on the whole process of warehousing of chemicals, is made on the basis of ascertained information. The first part of thesis describes legislative sources and safety requirements for work performance with chemicals. The second part is focused on the audit of warehousing itself. The risks, which appear on the workplace, are described there, as well as making suggestions of their elimination. The final chapter is dedicated to the improvement of warehouse safety.
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Identify synthetic polymers used in cosmetics and further test their biodegradation in aqueous setup in order to assess their impact on the environment / Identifiering av syntetiska polymerer i kosmetiska produkter och undersökning av miljöpåverkan genom analys av bionedbrytbarhetAyan, Hilal January 2017 (has links)
Plastics have a wide application field, where cosmetic products are one of them. Polymers which are building blocks to plastics exists in many variants, overall they can be categorized into two groups; microplastics and water soluble polymers. Both polymer types are important to study and understand since polymers in general are not covered by any legislation. To gain a more profound understanding of their impact on environment this study was conducted. In collaboration with SSNC (Naturskyddsföreningen), a database containing hundreds cosmetic products was processed. The most occurring polymers were quantified and prevalent ingredients having “poly” in their name were selected for further investigation namely Nylon 12-20 (microplast) and Acrylates C/10-30 Alkyl-crosspolymer (water soluble). A standardized analysis method OECD 301 F was performed to test the polymers biodegrading ability. Results from biodegradation method showed that, neither of the two polymers is readily biodegradable in aqueous environment, despite their different properties. In connection with the obtained results, a filtration analysis was performed, with the purpose to determine the possibility to capture the polymers using microfilters. Results mainly showed flowthrough of both polymers. Relating the results to reality implies that these polymers are not captured in waste water treatment plant due to inefficient filtration and thereby spread to the environment. In addition more research should be devoted to water-soluble polymers and their impact on nature. Based on all compiled results, it is proposed that legislation addressing microplastics should be edited and revised in such a way that water soluble polymers are included in future prohibitions (against microplastics). / Plast har många användningsområden varav kosmetiska produkter är ett av dem. I kosmetika används exempelvis naturliga ämnen, sådana som förekommer i naturen och således kan brytas ned. Sedan finns syntetiska polymerer, sådana som syntetiseras och tillverkas av människor. Det finns oerhört många varianter av syntetiska polymerer som används inom kosmetika, generellt kan de kategoriseras i två grupper; mikroplaster och vattenlösliga polymerer. Med hjälp av Naturskyddsföreningens databas som innehåller hundratals kosmetikaingredienser, söktes de komponenter som hade ”poly” i sitt namn eftersom de inte täcks av lagstiftning. Bland dessa, valdes två mest förekommande polymerer för att studeras vidare, nämligen Nylon 12-20 (mikroplast) och Acrylates C/10-30 alkyl crosspolymer (vattenlöslig). En standardiserad analysmetod OECD 301 F tillämpades för att testa deras biologiska nedbrytbarhet. Resultatet från nedbrytbarhetstestet visade att ingen av polymertyperna, trots deras åtskiljande egenskaper, är lättnedbrytbar i vattenmiljöer. I följd av resultatet från analysen genomfördes en filtreringsanalys på KTH, för att avgöra om respektive polymer går att fånga upp i olika storlekar av mikrofilter. Resultatet visade att ingen av dem fångades upp (med den utrustning som var tillgänglig på KTH). Baserat på resultaten föreslås det att lagstiftningar som innefattar mikroplaster bör redigeras och revideras på ett sådant sätt att vattenlösliga polymerer är inkluderade i framtida förbud (mot mikroplaster). Utöver detta bör mer forskning ägnas åt vattenlösliga polymerer och deras påverkan på naturen.
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Catchment management-model evaluation : verifying data for the implementation of the water release module of the WAS programJansen van Vuuren, A., Pretorius, E., Benade, N. January 2005 (has links)
Published Article / The Water Administration System (WAS) is designed to be a management tool for irrigation schemes and water offices that want to manage their water accounts and supply to clients through canal networks, pipelines and rivers. The ultimate aim of WAS is to optimize irrigation water management and minimize management-related distribution losses in irrigation canals. This research project focus on the implementation of the water release module of the WAS program at the Vaalharts irrigation scheme. WAS consists of four modules that are integrated into a single program that can be used on a single PC, a PC network system (in use currently at Vaalharts) or a multi-user environment. These modules can be implemented partially or as a whole, depending on the requirements of the specific scheme or office. The four modules are an administration module, a water request module; water accounts module and a water release module. The first three modules are already implemented at Vaalharts, while module four is implemented only partially. This module links with the water request module and calculates water releases for the main canal and all its branches allowing for lag times and any water losses and accruals. Any researcher in this field should first understand where water comes from and how it will be utilized before any calculations are attempted. Only then manipulation of the release volume can commence. To precisely calculate this water release, accurate data is needed to ensure that the correct volume of water is released into the canal network. This can be done by verifying existing data with field data. To optimize the management of the irrigation scheme the fully implemented WAS program need to be installed and running at the scheme. A series of data and calculation verification needs to be executed. The exercise will show the adequacy and correctness of the available database WAS uses to do the release calculation from. This will ensure improved management of the irrigation scheme, catchment and water resource sustainability. It is planned that the information generated from this project will be used in the compilation of an integrated catchment management information system, currently underway in the school of Civil Engineering and Built Environment at the Central University of Technology, Free State, South Africa.
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Rigid-Body Modelling of Forklift Masts and Mast Sway SimulationsLe Tran, Minh January 2016 (has links)
Reach truck masts are subjected to oscillations, which have significant impacts on the dynamics of the entire vehicle. Mast oscillations can cause undesirable outcomes in extreme situations and therefore it is desirable to be able to predict these outcomes before they occur. A forklift manufacturer in Mjölby initiated a thesis with the intention to obtain a model that can simulate mast sway for situations where oscillations occur. The objective of the thesis was to create a model of Triplex masts and find dependencies between model parameters and variables such as fork height and load. The thesis was conducted modelling the mast with a rigid multibody approach where torsion springs and dampers were used between mast parts to simulate mast elasticity. Clearance at the connections were considered and included in the model. The obtained model constitutes of 8 parameters that could be tuned to attain different oscillation characteristics. Parametric optimisation was carried out to find optimal sets of parameters for compliance with sway measurement tests with different load and fork height cases. The thesis has resulted in a model that is able to simulate mast sway with different oscillation characteristics depending on model parameters. Performed parametric optimisation resulted in parameters that reveal useful information about how model parameters depend on load and fork height. The method used for obtaining optimal parameters can likewise be applied to other mast models in order to gain insight into model parameters as functions of load and fork height.
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Hydraulic Energy Recovery System Utilizing a Thermally Regenerative Hydraulic Accumulator Implemented to a Reach TruckHänninen, Henri, Juhala, Jyri, Kajaste, Jyrki, Pietola, Matti 28 April 2016 (has links) (PDF)
The implementation of an energy recovery system for retreiving otherways wasted energy is an effective method for reducing the overall energy consumption of a mobile machine. In a fork lift, there are two subsystems that can be effectively modified for recovering energy. These are the driveline and the lift/lower function of the mast. This study focuses on the latter by studying a recovery system whose main component is a hydraulic transformer consisting of a hydraulic motor, a variable displacement pump and an induction motor. Since the flow rate/pressure - ratio can be modified, the utilization of the hydraulic transformer enables downsizing of the accumulator volume. However, the decrease of the gas volume leads to an increase in the compression ratio of the accumulator, which in terms leads to higher gas temperatures after charging and consequently to higher thermal losses during holding phase. In order to reduce these losses, a thermally regenerative unit was implemented to the gas volume of an accumulator to reduce the temperature build up during charging. In this study, the effect of improving the thermal characteristics of the accumulator to the efficiency of the whole energy recovery system is investigated by means of measurements.
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Intégration du risque chimique dans la conception de produits industriels. Application au secteur de l'aéronautiqueLemagnen, Maud 20 January 2011 (has links) (PDF)
Dans un contexte réglementaire contraignant (REACh), ce projet a pour but de développer une méthode permettant d'évaluer, le plus amont possible du processus de conception, le risque chimique potentiellement présenté par un équipement aéronautique depuis sa livraison jusqu'à sa fin de vie. Le résultat s'intègre dans l'ensemble des paramètres gérés par les concepteurs, dans un but d'amélioration de la traçabilité des substances dangereuses et de maîtrise du risque chimique présenté par l'équipement. Le développement de la méthode s'appuie tant sur l'analyse des modes d'évaluation classiques de risques chimiques, pour différents périmètres, que sur celle des pratiques de conception aéronautiques. En parallèle, des tests in situ en Bureaux d'Etudes sont réalisés itérativement, permettant de définir des outils d'évaluation et d'aide à la décision adaptés aux besoins identifiés des concepteurs. Les travaux aboutissent à la proposition d'une méthode permettant au concepteur de répondre à la problématique risque chimique à partir des seules données issues du processus de conception, rendant cette nouvelle approche miscible à ses activités quotidiennes.
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