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Abstract: The application of highly porous and 3D interconnected microcellular polyelectrolyte polyHIPE (PE-PH) monoliths based on (3-acrylamidopropyl)-trimethylammonium chloride as soilless cultivation substrates for in vitro embryo culture is discussed. The embryo axes isolated from chickpea seeds are inoculated onto the surface of the monoliths and allowed to germinate. Germination study show that the newly disclosed PE-PH substrate performs much better than the conventionally used agar as the germination percentage, shoot and root length, fresh and dry weight as well as the number of leaves are enhanced. The PE-PHs exhibit a higher absorption capacity of the plant growth medium, that is, 36 g·g–1 compared to agar, that is, 20 g·g–1, and also survive autoclaving conditions without failing. The key advantage over standard agar substrates is that they can be reused several times and also without prior sterilization. These results suggest that PE-PHs with exceptional absorption/retention properties and robustness have great potential as soilless substrates for in vitro plant cultivation.
Keywords: absorption, catalyst supports, germination, plants, porosity
Published in DKUM: 15.07.2024; Views: 114; Downloads: 10
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Abstract: Despite the current boost in the use of electric vehicles to reduce the automotive sector’s footprint, combustion vehicles are and will be present in our cities in both the immediate and long term. In this sense, catalytic converters, which are exhaust gas post-treatment systems for vehicle emission control, are critical for complying with increasingly stringent environmental regulations. This work proposes a systematic review to identify the most relevant knowledge regarding the parameters (materials, geometries, and engine conditions), conditions (cold start, oxygen storage, and deactivation), and mathematical models to consider in the design of catalytic converters. The Scopus database contains 283 records related to this review’s objective. After applying the inclusion and exclusion criteria, 65 reports were retrieved for evaluation. A table was created to present the results and prepare this manuscript. The evaluation revealed that the following topics were active: the study of non-noble catalyst materials, as well as new substrate materials and geometries, for designing more compact and cost-effective catalytic converters; the development of strategies to improve conversion during cold starts; and the development of accurate and fast estimation models.
Keywords: automotive converters, catalytic converters, emissions reduction, exhaust gas post-treatment, catalyst deactivation, oxygen storage, numerical models
Published in DKUM: 06.09.2023; Views: 453; Downloads: 34
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Abstract: Konkurenca je vsak dan večja in podjetja iščejo različne načine kako dobiti svoje mesto na trgu. To vodi v dejstvo, da želijo podjetja v današnjih dneh vedeti vse o svojih strankah in njihovih potrebah. Če strankam ne ponudimo kaj zanimivega, bodo odšli h konkurenci. CRM rešitve so programi, ki nam omogočajo, da shranimo velike količine pridobljenih podatkov o naših strankah. Če želimo imeti CRM rešitev, jo moramo najprej uvesti v podjetje. Toda, pred tem je potrebno poznati nekaj opredelitev o sami CRM rešitvi in kako nam lahko pomaga pri našem poslovanju, posebej pri prodaji, trženju, servisu in podpori. Na žalost je veliko projektov uvedbe neuspešnih. To je zaradi prepričanja podjetja, da je dovolj, če pokličemo uvajalca in mu prepustimo delo. Vendar moramo prispevati svoj del tudi mi. Najprej moramo spremeniti poslovne procese, da bodo ustrezali novi CRM rešitvi, nato prepričati zaposlene, zakaj je nova CRM rešitev boljša. Prepričati se moramo, da je dovolj vključen tudi menedžment in so tudi oni seznanjeni s podrobnostmi uvedbe. To so le nekateri dejavniki, ki nam pomagajo k uspešni uvedbi. Za učinkovitejše uvajanje je veliko ponudnikov CRM rešitev razvilo svoje metodologije za uvajanje le-teh. Te metodologije se lahko uporabijo kot okvir za uvedbo vsake nove CRM rešitve in pomagajo zmanjšati možnost neuspešne uvedbe.
Keywords: CRM, CRM rešitev, upravljanje odnosov s strankami, prodaja, trženje, servis in podpora, stranke, metodologija uvajanja, uvedba CRM, Maximizer CRM, Sure Step, Catalyst, ASAP metodologija.
Published in DKUM: 17.12.2012; Views: 3457; Downloads: 427
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Abstract: The main purpose of this work was combining the modern laboratory equipment (RC1 reaction calorimeter and ReactIRTMiC10 reaction analysis system) and the concept of the Taguchi fs design of experiment to determine the relative influence of important process parameters affecting the sucrose hydrolysis. The reaction was catalyzed by strong acidic cation-exchange resin Amberlite IR-120 in H+ form. Four process parameters, including reaction temperature (.), sucrose mass concentration (fÁS), catalyst mass concentration (fÁC) and the rotational frequency of the stirrer (fm) at four levels were considered in this study. Relative contributions of the proposed influencing process parameters on hydrolysis time were estimated by analysis of the variance (ANOVA). The results showed that . had a substantial effect on the reaction time (78,3 %), the fm and fÁC had a smaller ones (7,9 % and 6,4 %, respectively), meanwhile the remain fraction to 100 % represents error (7,4 %). The optimum conditions, where the time required for complete sucrose hydrolysis would be the shortest, are: .= 79 Keywords: sucrose hydrolysis, catalyst, Taguchi method, in-situ FTIR, reaction calorimeter RC1
Published in DKUM: 31.05.2012; Views: 2533; Downloads: 72
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