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Study of sensoric properties of organic semiconductors
Saska, Pavel ; Šedina, Martin (referee) ; Salyk, Ota (advisor)
Compounds based on diketopyrrolopyrrole are organic pigments that behave as semi-conductors. Their analogues with pyridyl side group are due to their sensitivity to hydrogen potentially useful as hydrogen sensors. The aim of this work was to examine properties of sensors with an active layer of diketopyrollopyrolle derivatives. The sensors were tested on an apparatus built for this purpose at FCH VUT in Brno. More specifically, changes to conductivity of these sensors in the presence of hydrogen under various conditions were studied.
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Sensoric properties of organic N-type semiconductors and their air stability
Saska, Pavel ; Vala, Martin (referee) ; Salyk, Ota (advisor)
Hydrogen has been for some time discussed as a successor to fossil fuels whose stocks are constantly running low. One of the crucial requirements for the possible usage of hydrogen as an energy carrier is our ability of reliable detection. In context with development of organic electronics there occurred a possibility to use derivatives of diketopyrrolopyrroles as sensing materials of hydrogen sensors. Derivatives of diketopyrrolopyrrole are organic pigments that behave as semiconductors. Their analogues with pyridyl side group are due to free electron pairs of nitrogen atoms sensitive to hydrogen. The problem of organic N-type semiconductors is in general their instability on the air. This thesis is focused on testing of hydrogen sensors with active layer made from derivatives of diketopyrrolopyrrole and judging their stability on the air.
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Cereal pests and their natural enemies
Honěk, Alois ; Martinková, Zdena ; Platková, Hana ; Saska, Pavel ; Skuhrovec, Jiří
The methodology mainly summarizes the new results and experiences of the author's team, which has been studying the biology of some cereal pests and their natural enemies for a long time. The aim is to draw attention to selected species of pests, to provide instructions on how to recognize them, in some cases to find out their current numbers in cereal stands and within the possibilities of current knowledge to predict further development of their abundance in a given stand and estimate yield reduction. Another goal is to recapitulate protection options with an emphasis on the use of natural enemies. The third goal is enlightenment. The methodology provides an accessible way to understand the biology and population development processes of cereal pests (especially aphids) so that the reader does not remain a blind user of unwarranted practical instructions, but can decide for himself according to the immediate situation.
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Growth and ontogeny of sexual size dimorphism in Cetoniinae (Coleoptera: Scarabaeidae)
Vendl, Tomáš ; Šípek, Petr (advisor) ; Saska, Pavel (referee)
6 Abstract Due to its effect on fitness and many biological processes is body size one of the most important attribute of organisms. Body size is positively correlated with fecundity in insects and other ectotherms. Growth, which determine body size, is therefore crucial feature of animals. Study of growth can elucidate some aspects of body size evolution. Unfortunatelly, many insects life-history studies do not consider its complexity, especially the existence of distinct larval instars. Inaccurate record of growth trajectory may result also in biased differences in growth between sexually dimorphic sexes. Aim of this thesis is to record growth trajectories of two flower beetle species (Coleoptera: Scarabaeidae: Cetoniinae). These growth trajectories enable to define proximate mechanisms of growth with regard to individual instars. Determination of developmental mechanisms of sexual size dimorphism is another goal of this study. The growth is clearly divided in three distinct periods. In each individual period (i.e. instar) is described by asymptotic curve. The instars are not independent on each other - the growth in following instar is influenced by growth in previous. There are no differences in growth characteristics between sexes. Sexual size dimorphism is caused by differences in growth rate between...
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Taxonomy and bionomy of the weevils of the tribe Hyperini (Coleoptera: Curculionidae)
Skuhrovec, Jiří ; Král, David (advisor) ; Bezděk, Aleš (referee) ; Saska, Pavel (referee)
Stanovisko k doktorské disertačnípráci Mgr. JiříhoSkuhrovce Taxonomiea bionomienosatcoviýchbroukůzeskupinyHyperini (Coleopteraz Curculionidae) JiříSkuhrovecnastoupildo doktorskéhostudiasjasnýmprojektem,kterýbyl aje v těsné návaznostinajehoprojektmagisterský.Stanoviskooborovéradyzoologiek podanému projektubylovíceneŽkladné,navícpodpořenéautoritouškolitelespecialistouRomanem Borovcem.ostatnístudijnípovinnostibyly splněnybezezbytku. Výslednýspisje postavennaosmipracíchajednomabstraktuzmezinárodní konference.Dvě z nichjsouvýištěnyv impaktovanýchčasopisech,atoZootaxaaJournalof EconomicEntomologl.Dalšítři jsoupublikoványv mezinárodníchrecenzovaných periodicích.Zbýek tvořítři dotiskupředloženémanuskripty. PráceprošlykvalitnímrecenznímŤízením.Jeprotopromnetéměřzbyečnésezde pokoušetnajítnedostatky,kterénějakýmpodivnýmřízenímosudu,unikly kriticemnohem přísnějšíchspecialistův danémoboru.Sezájmemjsemsi přečetli úvodníkomentář,ve kterémdefendendzasazujesvédílčívýsledkydoširšíhoteoretickéhorámcea přibližujeblíže problematikutaxonomie,bionomiea zoogeografieuvedenýchskupin' Zvýšeuvedenéhovyplývá,ženemámk předloženémuspisuŽádnénegativní komentářeanipóznámky.Jensnadbychseráddozvěděljakouproblematikuřešíkolega v současnédobě,čihodlářešitv blízkébudoucnosti,zdaplánujenapříkladřešenítaxonomie za...
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Growth and ontogeny of sexual size dimorphism in Cetoniinae (Coleoptera: Scarabaeidae)
Vendl, Tomáš ; Šípek, Petr (advisor) ; Saska, Pavel (referee)
6 Abstract Due to its effect on fitness and many biological processes is body size one of the most important attribute of organisms. Body size is positively correlated with fecundity in insects and other ectotherms. Growth, which determine body size, is therefore crucial feature of animals. Study of growth can elucidate some aspects of body size evolution. Unfortunatelly, many insects life-history studies do not consider its complexity, especially the existence of distinct larval instars. Inaccurate record of growth trajectory may result also in biased differences in growth between sexually dimorphic sexes. Aim of this thesis is to record growth trajectories of two flower beetle species (Coleoptera: Scarabaeidae: Cetoniinae). These growth trajectories enable to define proximate mechanisms of growth with regard to individual instars. Determination of developmental mechanisms of sexual size dimorphism is another goal of this study. The growth is clearly divided in three distinct periods. In each individual period (i.e. instar) is described by asymptotic curve. The instars are not independent on each other - the growth in following instar is influenced by growth in previous. There are no differences in growth characteristics between sexes. Sexual size dimorphism is caused by differences in growth rate between...
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Sensoric properties of organic N-type semiconductors and their air stability
Saska, Pavel ; Vala, Martin (referee) ; Salyk, Ota (advisor)
Hydrogen has been for some time discussed as a successor to fossil fuels whose stocks are constantly running low. One of the crucial requirements for the possible usage of hydrogen as an energy carrier is our ability of reliable detection. In context with development of organic electronics there occurred a possibility to use derivatives of diketopyrrolopyrroles as sensing materials of hydrogen sensors. Derivatives of diketopyrrolopyrrole are organic pigments that behave as semiconductors. Their analogues with pyridyl side group are due to free electron pairs of nitrogen atoms sensitive to hydrogen. The problem of organic N-type semiconductors is in general their instability on the air. This thesis is focused on testing of hydrogen sensors with active layer made from derivatives of diketopyrrolopyrrole and judging their stability on the air.
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Study of sensoric properties of organic semiconductors
Saska, Pavel ; Šedina, Martin (referee) ; Salyk, Ota (advisor)
Compounds based on diketopyrrolopyrrole are organic pigments that behave as semi-conductors. Their analogues with pyridyl side group are due to their sensitivity to hydrogen potentially useful as hydrogen sensors. The aim of this work was to examine properties of sensors with an active layer of diketopyrollopyrolle derivatives. The sensors were tested on an apparatus built for this purpose at FCH VUT in Brno. More specifically, changes to conductivity of these sensors in the presence of hydrogen under various conditions were studied.
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