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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.
41

Vliv dezintegrace vstupního materiálu na produkci methanu při anaerobní fermentaci / The influence of disintegration of the input material for the production of methane by anaerobic fermentation

Herman, Pavel January 2012 (has links)
This master‘s thesis deals with the influence of disintegration of brewer's grains for the production of biogas by anaerobic fermentation. The first part introduces us with the issue of biodegradable wastes. There are given their characteristics, ways of handling with them and legislative restrictions associated with them. In other sections there is a detailed description of anaerobic fermentation itself, including characteristics of biogas. Then there is issue of disintegration during fermentation including a list and characteristic of some disintegration methods. The main part of the thesis consists of description of the experiments on which it is observed increment of biogas based on the disintegration of brewer's grains and the evaluation of the individual experiments including the calculation of economic of the disintegration in laboratory conditions.
42

Desintegrace flotačně zahuštěného kalu / Disintegration of sludge thickened by flotation

Veverka, Jakub January 2014 (has links)
The main topic of this thesis is a research of influence of disintegration of sewage sludge on the production of biogas during the process of anaerobic fermentation. The theoretical part deals with issues and specific methods used during the process of waste water cleaning, furthermore it contains simplified description of waste water treatment plants and particular devices. The number of ways of processing sewage sludge and its potential utilization id also discussed. Following parts of the thesis analyze in detail my own process of anaerobic fermentation including important factors influencing this process. Comparison of aerobic and anaerobic fermentation and ecological perspective on the issue are included in this part. Another important part of the thesis deals with disintegration and description of the disintegration methods and devices. The fundamental part implies the analysis of the executed experiments. Experiments analyze the growth of biogas during anaerobic fermentation depending on the disintegration of sewage sludge. After that the evaluation of the experiments is stated together with economical calculations of the disintegration process executed in laboratory conditions.
43

Studium lisovacího procesu a vlastností tablet z různých typů hydrogenfosforečnanu vápenatého. / A study of the compaction process and the properties of tablets from different types of calcium hydrogen phosphate.

Koryťáková, Lenka January 2015 (has links)
The thesis evaluates anhydrous and dihydrate calcium hydrogen phosphate from the view point of the tensile strength, disintegration time of tablets depending on the compression force. Two firm products - Anhydrous Emcompress® and Di-Cafos® A 60 are used as anhydrate and Emcompress® is used as dihydrate. A compression force together with lubricants (magnesium stearate, sodium stearyl fumarate) and an addition of microcrystalline cellulose (Vivapur® 102) are the influential factors. In addition to the characteristics of tablets, the energy balance of compression is also evaluated. Used compression forces were 12, 16 and 20 kN. The compression force 12 kN was used for the mixtures containing Vivapur® 102. Total energy of compression, energy for friction and energy accumulated by tablet after compression increased with compression force. The highest values were at Anhydrous Emcompress® , an addition Vivapur® 102 increased these values. There weren't more significant differences among the values of decompression energy. Plasticity decreased with the growing compression force, the highest values were at Anhydrous Emcompress® , Vivapur® 102 increased that. Tensile strength increased with compression force, Emcompress® provided the strongest tablets, Di-Cafos® A 60 provided at least strong tablets. Vivapur...
44

Skutečné pokusy o etablování nových států či efemérní projekty? Případ Azawadu, republiky Logone a chalífátu Boko Haram / Full-fledged attempts at establishing new states or ephemeral projects? Case study Azawad, Republic of Logone and Boko Haram chaliphate

Čepičková, Lucie January 2017 (has links)
This diploma theses deals with attempts to declare independent states, namely in the case of the Republic of Azawad, Logone and Boko Haram caliphate, which originated between 2012 and 2015. Today, the existence of deviant forms of the state is nothing new, so there are many concepts and classifications that relate to this issue. For this theses will be the significant particular concept of states-within-states by Ian Spears and Paul Kingston and the classification by Bartosz Stanislawski, extended by authors Katarzyn Pełczyńska-Nałęc, Krzysztof Strachot and Maciej Falkowski. The subsequent description of the causes, the way of dominating the area and the events after the declaration of the independent state itself in the individual case studies will lead to a analysis of the way in which the area is administrated or the newly established institutions. Due to this analysis, it will be able to apply the states-within-states concept and Bartosz Stanislawki's classification and then determine whether this application is possible in all three cases. The last part of the work, which should confirm or disapprove the main hypothesis of the work, will then be used to evaluate whether the specific attempts are rather effective or ephemeral projects.
45

The Balkans after 1991 through the prism of geopolitics

Sharevski, Mario January 2014 (has links)
Thesis deals with the issue of the conceptualization, analysis and understanding of the Balkans after 1991 as a specific geopolitical area in order to examine the proclivity of the region towards conflicts and give general idea of the geopolitical position of the Balkans in local and global context. First, the definition of the Balkans and its borders in physic and politico geographical structure along with the historical definitions and geopolitical position settings and significance prior 1991 are tackled. Then follows the application of the geopolitical theories and concepts on the geopolitical map with the states of the Balkans after 1991 in order to conceptualize the area and thus having a framework for examination and comparison of the territorial changes and geopolitical events that occurred in this historical period as well as for better understanding of strategic significance of internal and external geopolitical position of the Balkans. As a third step follows the explanation and outline of the greater territorial irredentist and geopolitical concepts of the Balkan nation states which have been revived and actualized in the period after 1991 serving as a background and basic platform for their geopolitical agenda. Lastly, the thesis tackles the territorial changes that came as a result of...
46

Bosňácká menšina v Srbsku a Černé Hoře v období desintegrace Jugoslávie. Genese národní identity / Bosnian Minority in Serbia and Montenegro in the Period of Desintegration of Jugoslavia. Genesis of National Identity

Heler, Daniel January 2014 (has links)
This thesis "The Bosnian minority in Serbia and Montenegro in the period of disintegration of Yugoslavia" is, based on the theoretical concept of the problem of modern nation and modern state formation, in constructivist approach and its consequences for internal security connected with the existence of national minorities, focusing on setting the problems of forming the national identity of the Muslims or the Bosniaks into a wider framework of the second and third Yugoslavia disintegration. The matter of bosniak nation genesis is focused on the territory of Saniak of Novi Pazar, which is situated in a very sensitive area among Serbia, Montenegro, Bosnia and Herzegovina and Kosovo. The main goal is to answer the following questions: What was the development of the Muslim and Bosniak national identity like in the conditions of peripheral territory of Sanjak? Based on the perception of the local Bosniak national elites, what was the relation of the Bosniak/Muslim minority towards the state, the regime, and the nation it lived in/with like? What correlations between the state, political changes in Yugoslavia, Serbia and Montenegro and the perception of real national existence of Muslim/Bosniak community within these states can be observed? The thesis is not supposed to be a narrowly focused study, but a...
47

Effect of Physico-Chemical Factors on the Disintegration Behavior of Calcareous Shale

Nandi, Arpita, Whitelaw, Mick 01 November 2009 (has links)
Calcareous shale, which is often encountered in construction projects, has a variety of physical and chemical properties that influence disintegration behavior of the rock mass. The diverse behavior of calcareous minerals in shale adds to the complexity of geotechnical investigations. Abundance of calcareous minerals is known to improve shale rock strength, although, when exposed to seasonal wetting and drying cycles, disintegration is rapid. The intent of this study is to statistically evaluate the disintegration behavior of calcareous shales in relation to their physico-chemical properties. Shale samples from fresh rock cuts and talus were tested using a multi-cycle slake durability index (Id), X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) elemental analysis, bulk density, natural water content, and porosity. A relationship was found between the degree of disintegration and the abundance of calcareous minerals, especially calcite and gypsum. Higher porosity and elevated water content were observed in highly weathered shales. Additionally, the efficiency of the Id test as an indicator of the degree of disintegration was evaluated. Grain-size distribution (GSD) analysis of disintegrated talus was compared with fragmental material of two-and five-cycle Id (Id2 and Id5) tests. The Coefficient of Uniformity (Cu) and Coefficient of Curvature (Cc) of Id5 materials showed satisfactory correlation with Cu and Cc of talus material. It is demonstrated that when compared to the conventional Id2 test, multi-cycle Id tests more precisely predict the disintegration pattern of shale and can be used to evaluate shale in terms of degree of disintegration.
48

The failure of integrated transport policy in Germany: a historical perspective

Schwedes, Oliver 02 December 2019 (has links)
In order to reach a sustainable traffic development, the European Union follows the central idea of an integrated transport policy. In contrast to the widely accepted concept, the EU recently had to admit that in fact transport development goes in the opposite direction. This contradiction has to be explained. The article describes the long lasting succession of efforts to implement a far-reaching cooperation in the transport sector as is aspired to by an integrated transport policy. In each case, though, the political idea of cooperation was superseded by the economic one of competition. Therefore, the author argues in favour of a detailed scientific analysis of the necessary political conditions for an integrated transport policy, instead of continuing an untested concept.
49

Subtractive Renormalization of the NN Interaction in Chiral Effective Theory and the Deuteron Electro-disintegration Calculation

Yang, Chieh-Jen 23 September 2010 (has links)
No description available.
50

Avaluació del procés de desintegració de papers recuperats

Puig Serramitja, Josep 19 November 2004 (has links)
La desintegració és una etapa important en la recuperació de paper vell, ja que té importants conseqüències en consum d'energia i en el comportament de les etapes posteriors.Per això els objectius es centren en analitzar la desintegració des del punt de vista del temps de desintegració, els aspectes energètics, modelització de la màquina de desintegració utilitzada i anàlisi dels factors de cisallament calculats com a mesura global de les forces implicades en la desintegració. Els autors que hi han treballat donen diferents explicacions a aquestes forces. Fins avui només s'ha pogut avaluar qualitativament la influència que tenen cada un dels mecanismes en el temps necessari per a desintegrar i en el consum energètic. Les característiques reològiques de les suspensions papereres, i el seu comportament no newtonià tenen una clara influència en el consum energètic i les forces de desfibrat en el desintegrador.Els experiments de desintegració s'han realitzat en un púlper convencional, amb tres tipus de paper recuperat: paper estucat d'alta qualitat imprès offset (PQ), paper revista estucat imprès en color (PR), paper blanc imprès en impresora làsser (PF).Anàlisi del temps de desintegracióPer cada un del papers estudiats (PQ, PR i PF), les fraccions màssiques des de 0.06 fins a la màxima que estat possible per cada paper (de 0.14 a 0.18), i a dues velocitats d'agitació diferents, s'ha determinat el temps de desintegració (tD) fins a aconseguir un índex de Sommerville de 0.01%. S'obté que en augmentar la fracció màssica disminueix potencialment el temps de desintegració. S'ha estudiat la velocitat de desintegració, la producció teòrica del púlper en cada cas, i la seva relació amb les forces d'impacte i de fregament que produeixen la desintegració.Aspectes energèticsEl consum específic d'energia (SEC), definit com l'energia consumida per a desintegrar 1 kg de paper recuperat, disminueix molt en augmentar Xm, ja que a més de disminuir l'energia consumida en cada desintegració, el contingut en paper és més elevat. Pel disseny de desintegradors, cal tenir en compte que en augmentar Xm i en augmentar la velocitat, sempre augmenta la potència consumida. Però així com els beneficis de treballar a Xm alt són de 10 vegades en termes de SEC i de producció, l'augment de potència és només de l'ordre de 2 vegades la necessària respecte de la Xm baixa. Viscositat aparent i energia de fluiditzacióS'estudia la relació entre el temps de desintegració, les forces de fregament i els valors de viscositat aparent de la bibliografia. Per cada paper i velocitat s'ha observat que el consum específic d'energia disminueix en funció de la viscositat aparent.Reologia del púlperUtilitzant el mètode de Metzner i Otto (1957) per determinar la viscositat aparent mitjana de les suspensions papereres, modificat per Roustan, s'ha caracteritzat el pulper mitjançant el model: Np= K· Rex·Fry S'han utilitzat dissolucions de glicerina com a fluid newtonià per a calcular les constants d'ajust, i a partir d'aquí, aïllar la viscositat aparent en funció de la potència neta i els paràmetres d'agitació.La viscositat aparent, d'acord amb Fabry (1999) es substitueix pel concepte de factor de cisallament.Factor de cisallamentCalculat el factor de cisallament per a cada paperot i condicions d'agitació, s'ha relacionat amb Xm, SEC, tD, consum de potència, potència instal·lada i fracció cel·lulòsica. El factor de cisallament és un paràmetre útil per a quantificar les forces globals implicades en la desintegració. / Disintegration is an important stage in paper recovery and it has important consequences in energy consumption and in the following stages.The objectives of this thesis are focussed in analyzing disintegration considering disintegration time, power aspects, modelisation of the disintegration machine and analysis of the calculated shear factors as a global measurement of the forces implied in the disintegration.Until now, it has only been possible a qualitative evaluation of the influence of every mechanism in the time necessary to disintegrate the pulp, and in the power consumption.Rheological characteristics of suspensions and their non-Newtonian behaviour it is known that clearly influence power consumption and defibering forces acting during repulping. Disintegration experiments have been made in a conventional pulper, with three types of recovered paper: high quality coated printed offset paper, magazine coated colour printed paper and white laser printed paper.Analysis of disintegration timeTime necessary to achieve a Somerville index of 0.01%, was determined for each paper studied, at mass fractions ranging from 0,06 until the maximum possible for each type of paper (0,14 or 0,18) and at two different agitation speeds. It has been found that when increasing the mass fraction, disintegration time decreases potentially. Disintegration speed and theoretical production of pulp have been studied in each case, and they have been related with friction and impact forces.Power aspects Specific energy consumption (SEC) defined as the energy consumed during disintegration of 1 kg of recovered paper, was reduced with increasing mass fraction (Xm), because the energy consumed during disintegration decreases and the pulp contend in the pulper is higher. And increase of Xm and pulper agitation speed always increases the power consumed. An increase of only 2 times of power consumption (due to working at high Xm) produces benefits in SEC and production of 10 times.Apparent Viscosity and fluidisation energy Relation between disintegration time, friction forces and apparent viscosity were studied. For each paper and speed it has been observed that SEC was reduced when increasing apparent viscosity.Rheology of pulper Using Metzner and Otto methodology to determine average apparent viscosity of suspensions, modified by Roustan, pulper was characterized by means of model Np=K·Rex·Fry. Glycerine dissolutions have been used as Newtonian fluid to calculate constants of adjustment, and from here, apparent viscosity was determined from net power and agitation parameters. Apparent viscosity, in agreement with Fabry, is replaced by the concept of shear factor.Shear FactorOnce calculated the shear factor for each type of paper and conditions of agitation, the values obtained have been related to Xm, SEC, td, power consumption, installed power and cellulose fraction. Shear factor is a useful parameter to quantify the global forces acting in disintegration process.

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