Estudi tècnic-econòmic per a la instal·lació d'una granja d'ànecs per a producció de foie-gras situada en el terme municipal de Fontanals de Cerdanya

Inversors però, principalment professionals de l'àmbit agrari, per tal de buscar una diversificació de l'activitat agrícola i ramadera que desenvolupen a les seves finques, sobretot joves emprenedors, poden estar interessats en produccions alternatives com la producció d'ànecs per a foie-gras, per tal de complementar la seva renda agrària. Actualment cal augmentar la competitivitat de les finques agrícoles per tal que aquestes siguin econòmicament viables. L’objectiu de l'estudi és determinar la viabilitat econòmica d’una explotació ramadera d’ànecs per a la producció de foie-gras, en el terme municipal de Fontanals de Cerdanya, analitzant les diverses alternatives en quant a dimensionament i disseny de les instal·lacions, segons el cicle productiu de l’animal. L'alternativa escollida per realitzar l'estudi es la de semi-integració (cria, engreix i embocat), de règim semi-intensiu (durant l'etapa de l'engreix), amb animals mascles de la raça híbrida Mulard. Les instal·lacions tindran una capacitat de 6.500 animals, amb lots de 250 caps. Aquest dimensionament permet, durant la fase d'embocat, en la qual es requereix més dedicació, que la demanda de mà d'obra pugui ser satisfeta per un únic treballador. La principal conclusió que es pot extreure de l'estudi és que la inversió projectada és massa elevada i que aquesta econòmicament no és viable o rendible, ja que la despesa és massa elevada. Es mouen uns fluxos de caixa molt elevats i el marge comercial és molt reduït. Únicament si l'objectiu del promotor és obtenir una remuneració per la seva feina, sempre i quan és produeixi un augment del preu actual de la carn i una disminució del preu del pinso, es podria recomanar que es portés a terme la implantació de l'explotació, intentant, però, reduir la despesa d'execució de construccions i instal·lacions.

Effects of landscape evolution on flora and habitats in agricultural mosaics

A landscape mosaic is a landscape that consist of various patches, inhabited by different habitat communities over time. Agricultural mosaics area result of the long history between societies and the environment. The understanding of the driving forces for change in this landscapes, and their effect on biodiversity, allow the development of useful tools to assess and manage natural heritage. Plant diversity, endangered plant species and interesting habitats receive the center of attention, because of their capability to integrate and reflect the main changes of this landscapes after medium and long-term.

Efficient synthesis of sulfonamide derivatives on solid supports catalyzed using solvent-free and microwave-assisted methods

In this work we report the synthesis of sulfonamide derivatives using a conventional procedure and with solid supports, such as silica gel, florisil, alumina, 4Å molecular sieves, montmorillonite KSF, and montmorillonite K10 using solvent-free and microwave-assisted methods. Our results show that solid supports have a catalytic activity in the formation of sulfonamide derivatives. We found that florisil, montmorillonite KSF, and K10 could be used as inexpensive alternative catalysts that are easily separated from the reaction media. Additionally, solvent-free and microwave-assisted methods were more efficient in reducing reaction time and in increasing yield.

Palladium-supported catalysts in methane combustion: comparison of alumina and zirconia supports

Palladium catalysts supported on alumina and zirconia were prepared by the impregnation method and calcined at 600 and 1000 ºC. Catalysts were characterized by BET measurements, XRD, XPS, O2-TPD and tested in methane combustion through temperature programmed surface reaction. Alumina supported catalysts were slightly more active than zirconia supported catalysts, but after initial heat treatment at 1000 ºC, zirconia supported palladium catalyst showed better performance above 500 ºC A pattern between temperature interval stability of PdOx species and activity was observed, where better PdOx stability was associated with more active catalysts.

Sähkön ja lämmön yhteistuotanto haasteellisilla polttoaineilla

Maailman energian kulutuksen lisääntymisen ja ilmastonmuutoksen myötä energiantuotannossa joudutaan jatkuvasti sopeutumaan muuttuviin tilanteisiin ja haasteisiin. Polttoteknillisiä haasteita aiheuttavat pelto- ja kierrätyspolttoaineet ovat lisäämässä osuuttaan uusiutuvien polttoaineiden joukossa. Jotta kyseisiä haasteellisia polttoaineita pystytään hyödyntämään, täytyy niiden aiheuttamat ongelmat tuntea ja laitevalmistajien kehittää niiden hyödyntämiseen sopivaa tekniikkaa. Tässä diplomityössä käydään läpi tulevaisuudessa käytettävät polttoaineet, nykyiset päästörajat, kiinteiden polttoaineiden poltto- ja kaasutustekniikat sekä likaantumis-, kuonaantumis- ja korroosiomekanismit voimalaitoskattiloissa. Työssä tutkitaan, onko haasteellisten polttoaineiden käyttöön investoiminen järkevää ja mikä nykypäivän tekniikoista on kannattavin. Myös välitulistuksen, lauhdeperän ja apujäähdyttimen kannattavuuksia vertaillaan sähkön ja lämmön yhteistuotannossa. Tuloksiksi saatiin, että edullisten peltobiomassojen ja kierrätyspolttoaineiden käyttäminen, joko perinteisten polttoaineiden seassa tai pääpolttoaineena, on nykyhinnoilla perinteisiin polttoaineisiin verrattuna kannattavaa. Investoiminen kierrätyspolttoaineiden valmistuslaitteisiin maksimoi kierrätyspolttoaineista saatavaa hyötyä. Välitulistuksen todettiin soveltuvan huonosti vastapaineprosessiin, sillä siitä saatava sähköntuotannon lisäys on hyvin pieni. Lauhdeperän ja apujäähdyttimen vertailuissa huomattiin, että lauhdeperä on kannattava investointi, jos sähkön ja lämmön hintaero pysyy tarpeeksi suurena. Haasteellisilla polttoaineilla pystytään pienentämään kasvihuonepäästöjä ja korvaamaan fossiilisten polttoaineiden käyttöä.

Osingonjakopolitiikan määräytyminen ja sen osakekurssivaikutukset Helsingin pörssissä

Tämän työn tarkoituksena oli tutkia lineaarisen regressioanalyysin avulla sekä osingonjakopolitiikan määräytymiseen vaikuttavia tekijöitä että osinkojen osakekurssivaikutusta Helsingin pörssissä. Osinkopolitiikan määräytymistä tutkittiin yhtiön koon, kannattavuuden, velkaisuuden, investointi- ja kasvumahdollisuuksien sekä sisäpiirin omistuksen avulla. Käytetty aineisto koostuu Helsingin pörssissä noteerattujen yhtiöiden tilinpäätösluvuista ja osakekurssitiedoista vuosina 2000-2010. Empiiriset tutkimukset osoittivat, että osinkotuottoon vaikuttavia tekijöitä Helsingin pörssissä ovat yhtiön kannattavuus, velkaisuus, investointi- ja kasvumahdollisuudet sekä sisäpiirin omistus. Saadut tulokset ovat samansuuntaisia aikaisempien tutkimusten kanssa. Toinen merkittävä löydös on, että osingoilla todettiin olevan positiivinen yhteys osakekurssimuutoksiin Helsingin pörssissä. Osinkojen ja osakekurssin välinen yhteys tukee signalointiteoriaa.

Natural regeneration in abandoned fields following intensive agricultural land use in an Atlantic Forest Island, Brazil

The time required to regrowth a forest in degraded areas depends on how the forest is removed and on the type of land use following removal. Natural regeneration was studied in abandoned old fields after intensive agricultural land use in areas originally covered by Brazilian Atlantic Forests of the Anchieta Island, Brazil in order to understand how plant communities reassemble following human disturbances as well as to determine suitable strategies of forest restoration. The fields were classified into three vegetation types according to the dominant plant species in: 1) Miconia albicans (Sw.) Triana (Melastomataceae) fields, 2) Dicranopteris flexuosa (Schrader) Underw. (Gleicheniaceae) thickets, and 3) Gleichenella pectinata (Willd.) Ching. (Gleicheniaceae) thickets. Both composition and structure of natural regeneration were compared among the three dominant vegetation types by establishing randomly three plots of 1 x 3 m in five sites of the island. A gradient in composition and abundance of species in natural regeneration could be observed along vegetation types from Dicranopteris fern thickets to Miconia fields. The gradient did not accurately follow the pattern of spatial distribution of the three dominant vegetation types in the island regarding their proximity of the remnant forests. A complex association of biotic and abiotic factors seems to be affecting the seedling recruitment and establishment in the study plots. The lowest plant regeneration found in Dicranopteris and Gleichenella thickets suggests that the ferns inhibit the recruitment of woody and herbaceous species. Otherwise, we could not distinguish different patterns of tree regeneration among the three vegetation types. Our results showed that forest recovery following severe anthropogenic disturbances is not direct, predictable or even achievable on its own. Appropriated actions and methods such as fern removal, planting ground covers, and enrichment planting with tree species were suggested in order to restore the natural forest regeneration process in the abandoned old fields.

Compton scattering tomography for agricultural measurements

This paper presents a new approach in tomographic instrumentation for agriculture based on Compton scattering, which allows for the simultaneous measurements of density and moisture of soil samples. Compton tomography is a technique that can be used to obtain a spatial map of electronic density of samples. Quantitative results can be obtained by using a reconstruction algorithm that takes into account the absorption of incident and scattered radiation. Results show a coefficient of linear correlation better than 0.81, when comparison is made between soil density measurements based on this method and direct transmission tomography. For soil water contents, a coefficient of linear correlation better than 0.79 was found when compared with measurements obtained by time domain reflectrometry (TDR). In addition, a set of Compton scatter images are presented to illustrate the efficacy of this imaging technique, which makes possible improved spatial variability analysis of pre-established planes.

Computational modeling for irrigated agriculture planning. Part II: risk analysis

Techniques of evaluation of risks coming from inherent uncertainties to the agricultural activity should accompany planning studies. The risk analysis should be carried out by risk simulation using techniques as the Monte Carlo method. This study was carried out to develop a computer program so-called P-RISCO for the application of risky simulations on linear programming models, to apply to a case study, as well to test the results comparatively to the @RISK program. In the risk analysis it was observed that the average of the output variable total net present value, U, was considerably lower than the maximum U value obtained from the linear programming model. It was also verified that the enterprise will be front to expressive risk of shortage of water in the month of April, what doesn't happen for the cropping pattern obtained by the minimization of the irrigation requirement in the months of April in the four years. The scenario analysis indicated that the sale price of the passion fruit crop exercises expressive influence on the financial performance of the enterprise. In the comparative analysis it was verified the equivalence of P-RISCO and @RISK programs in the execution of the risk simulation for the considered scenario.

Operational characteristics of four metering systems for agricultural fertilizers and amendments

The use of fertilizers and solid amendments in agriculture generates special interest for their effect on crop productivity, as well as for their environmental impact. The efficient use of these products demands knowing their physical and mechanical properties, the storing conditions effect and the operational characteristics of the metering systems used in the fertilizing equipment. In this context, the present study was developed with the purpose of evaluating the operational characteristics of different fertilizing metering systems and to determine the adequate metering system-product operational parameters, using powder lime, powder gypsum, granular 10-30-10 (N-P-K), and granular urea. Operational differences were established among four types of commercial fertilizer metering systems, including wire auger, star-shaped feed wheel, feed screw and ridged traction wheel. The study found that the unloading rate depends directly on the fertilizer metering system's rotating speed and is affected by particle size, repose angle, bulk density and moisture content of the applied product. The wire auger and star-shaped feed wheel metering systems were adequate for the distribution of powder products and the feed screw for granulated fertilizers. Furthermore, theoretical and experimental characteristic equations were established, defining curves for calibration and handling of the products plus the rotating speed range in which a better distributing behavior was achieved.