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Optimization of supercritical fluid extraction of sweet wormwood ( artemisia annua l.) using design expert
No full textSladki pelin ( Artemisia annua L.) je zdravilna rastlina, ki vsebuje antimalarik artemizinin. Po strukturi je seskviterpenoidni lakton, točen mehanizem delovanja artemizinina še ni raziskan.
Cilj diplomskega dela je po eksperimentalnem načrtu programa Design Expert pro 13 izvesti superkritično ekstrakcijo s CO2 in ultrazvočno ekstrakcijo, kjer kot topilo uporabimo etanol. Pridobljenim ekstraktom smo nato določili antioksidativne lastnosti z metodo DPPH in z LC-MS/MS določili vsebnost artemizinina. Glede na dobljene rezultate smo obe ekstrakcijski metodi optimizirali in rezultate statistično obdelali.
Ugotovili smo, da so izkoristki višji pri višji temperaturi, srednje visokih tlakih in daljšem času ekstrakcije. Pri obeh ekstrakcijah imata opazovana parametra pomemben vpliv in sta medsebojno odvisna. Pri ultrazvočni ekstrakciji smo najvišje vrednosti za antioksidativno aktivnost dosegli pri temperaturi med 42 in 50 ⁰C ter času med 10 in 30 min. S superkritično ekstrakcijo pa smo maksimum dosegli pri temperaturi 40 ⁰C in tlakih med 250 in 300 bar. Vsebnost artemizinina je bila pri ultrazvočni ekstrakciji najvišja pri temperaturi 40 ⁰C in času med 3 in 25 min. Najvišje vsebnosti artemizinina pri superkritični ekstrakciji pa so bile dosežene pri temperaturi med 40 in 45 ⁰C ter tlakih med 200 in 300 bar.Sweet wormwood (Artemisia annua L.) is a medicinal plant, known of its primary active substance artemisinin. Its structure is a sesquiterpenoid lactone and the exact mechanism of action of artemisinin has not yet been investigated.
The aim of the research was to perform a supercritical CO2 extraction and ultrasound extraction using ethanol as the solvent, following the experimental plan with the Design Expert Pro 13 program. The antioxidative properties of the obtained extracts with the DPPH method were investigated and the artemisinin content has been determined using the LC-MS/MS method. Ultimately, based on the analytic results, the extraction methods have been optimized and statistical processing of the results have been performed.
As observed, the yields were higher at higher temperatures, medium-level pressures and longer extraction times. In the process of either extraction the observed parameters have a large impact and show close interdependence. With the ultrasound extraction, the highest values of antioxidative activity have been measured at temperatures between 42 and 50 ⁰C and extraction times between 10 and 30 minutes. Whereas using supercritical CO2 extraction the maximum at the temperature of 40 ⁰C and pressures between 250 and 350 bar were noticed. The overall artemisinin content was highest when ultrasound extraction was performed at 40 ⁰C and lasted between 3 and 25 minutes and when supercritical CO2 extraction was performed at temperatures between 40 and 45 ⁰C and pressures between 200 and 300 bar
MEMS accelerometer temperature calibration device
No full textZaključno delo opisuje postopek zasnove, izdelave ter testiranja naprave za temperaturno kalibracijo pospeškometra MEMS. Potreba po tovrstni napravi se je pojavila v podjetju, ki se ukvarja z razvojem ter izdelavo merilnih naprav, s katerimi merimo pospeške. V merilni napravi se nahaja pospeškomer MEMS ter ostala potrebna periferija za zajemanje meritev. Tovrstne merilne naprave se pogosto uporabljajo za monitoring večjih konstrukcij. Za te namene je na teh merilnih napravah treba izvesti temperaturno kalibracijo, s katero kompenziramo vpliv temperature na meritve pospeškov. V zaključnem delu je na kratko opisano teoretično ozadje delovanje pospeškometrov MEMS. Predstavljen je problem temperaturnega vpliva na meritve pospeškometra MEMS. V nadaljevanju pa je opisan postopek zasnove, konstruiranja, avtomatizacije in nazadnje tudi testiranja naprave za temperaturno kalibracijo pospeškometrov MEMS.This thesis describes the process of designing, building and testing a MEMS accelerometer temperature calibration device. The need for such a device arose in a company, which is engaged in the development and manufacture of measuring devices. The measuring device contains a MEMS accelerometer and other necessary peripherals to capture measurements. This device is often used for the monitoring of large structures. For these purposes, it is necessary to perform a temperature calibration on the measuring device to compensate for the influence of temperature on the acceleration measurements. In this paper, the theoretical background of MEMS accelerometers is briefly described. The problem of temperature influence on MEMS accelerometer measurements is presented. Then the procedure for the design, construction, automation and finally the testing of the temperature calibration device for MEMS accelerometers is described
Processing of ore residue in Cinkarna Celje d.d.
No full textSkrb za okolje in ekološke regulacije so podjetja v zadnjih letih vzpodbudila v iskanje trajnostnih industrijskih rešitev. Čeravno se zdi, da ekološki oziroma okoljski inženiring in posodabljanje proizvodnje prinašata le veliko investicij ter manjše končne prihodke, ni tako. Z razvojem novih metod in tehnologij je možno v veliki meri enake procese izvesti ceneje, učinkoviteje ter bolj trajnostno naravnano. V magistrskem delu je predstavljen razvoj metode ponovne uporabe odpadnega rudnega ostank, z namenom povečanja učinkovitosti končne proizvodnje pigmentnega titanovega dioksida. Raziskave kažejo, da je možno z relativno ugodnimi in preprostimi postopki iz odpadnega materiala pridobiti med 65 in 75 odstotki titanovega dioksida, ki bi drugače pristal na deponiji, pri čemer se masa končnega odpada zmanjša tudi do 65 odstotkov.Environmental awareness and ecological regulations have encouraged companies to search for sustainable industrial solutions in recent years. Although it may seem that environmental engineering and modernization of production only brings a lot of investment and lower final income, this is not the case. With the development of new methods and technologies, it is possible to carry out the same processes cheaper, more efficiently and more sustainably. The master\u27s thesis presents the development of a method of reusing waste ore residue, with the aim of increasing the efficiency of the final production of pigment titanium dioxide. Research shows that it is possible to recover between 65 and 75 percent of the titanium dioxide that would otherwise end up in a landfill with relatively inexpensive and simple procedures, while the mass of the final waste is reduced by up to 65 percent
Workshop Trial and Testing of S770QL Steel Pipe Welding Technology
No full textMagistrsko delo opisuje sistematično postopanje, kadar je potrebno podjetje in varilca certificirati, za izvajanje zahtevnega varilnega postopka. V prvem koraku, je treba s pomočjo teoretične oziroma raziskovalne metode določiti tehnologijo varjenja, na osnovi katere nato v procesu delavniške probe izdelamo varjence in sočasno izvedemo nadzor varjenja. Ustreznost izbire varilne tehnologije, ovrednotimo na osnovi mehanskih lastnosti zvarnega spoja. Analiza meritev nadzora varjenja, je pokazala odstopanje od zastavljene tehnologije varjenja, s čim je dokazana smiselnost izvedbe delavniške probe, pred postopkom certifikacije. Mehanske lastnosti drugega poizkusa zvarnega spoja, ki so rezultat opravljenih neporušnih in porušitvenih preiskav so ustrezne, torej je tehnologija varjenja ustrezna.The master\u27s thesis describes a systematic procedure for when it is necessary to certify the company and the welder for the implementation of a demanding welding procedure. In the first step, it is required to determine the welding technology with the help of a theoretical or research method. In the process of the workshop trial, based on the welding technology, welds are being produced, while simultaneously welding control is carried out. The correctness of the choice of welding technology is evaluated on the basis of the mechanical properties of the weld joint. The analysis of welding control measurements showed a deviation from the set welding technology, which proves the feasibility of conducting a workshop trial before the certification process. The mechanical properties of the second attempt at the welded joint, which are the result of non-destructive and destructive tests, are adequate, therefore the welding technology is adequate
System models for the HIL testing in automotive industry on FPGA with dSpace software
Get PDFV tej magistrski nalogi je predstavljeno testiranje realnega sistema, ki se uporablja v avtomobilski industriji z metodo strojne opreme v zanki. Uporabil se je realen krmilnik, ki merjenih podatkov ni dobil iz senzorjev, ampak so bili simulirani na strojni opremi. Za simuliranje se je uporabil tako računalniški procesor kot tudi FPGA (programljivo polje logičnih vrat) vezje. Za naš namen se je uporabila strojna in programska oprema podjetja dSpace. Izvedlo se je programiranje testov, nalaganje modela na strojno opremo, izvedba testov in beleženje rezultatov, ki so bili nato vneseni v orodje Polarion. Prav tako se je evaluirala uspešnost rezultatov testov.This master\u27s thesis presents the testing of a realistic system applied in automotive industry using the hardware-in-the-loop method. A real controller was used, which did not receive the measured data from sensors, but was simulated on hardware. Both a computer processor and an FPGA (Field Programmable Gate Arrays) circuit were used for the simulation. For our purpose, dSpace hardware and software were used. Test programming was carried out, the model was loaded onto the hardware, the tests were executed and the results were recorded and uploaded to the Polarion tool. The performance of the test results was also evaluated
Design and construction calculation of a regulation gate on a river dam
Get PDFNamen magistrskega dela je izvesti analizo nosilnosti in dimenzioniranje jeklene konstrukcije
regulacijske zaklopke na prelivnem objektu visokovodnega zadrževalnika Selška Sora. Jeklena
konstrukcija je dimenzionirana skladno s standardom DIN_19704 ter Eurokod 3 in je izdelana iz materiala S355J2+N. V izračunu se je upoštevala obtežba vode v normalnem načinu obratovanja.
Izvedla se je tudi analiza in izračun dvižni sil, ki imajo neposreden vpliv na samo nosilnost konstrukcije zaklopke.
V okviru izračuna jeklene konstrukcije je bila izvedena analitična analiza posameznih elementov konstrukcije ter numerična analiza s pomočjo programskega paketa PrePoMax.
Z potrebe določitve dvižnih sil zaklopke je bila izvedena analiza večfaznega toka vode čez zapornico.The purpose of the thesis is to carry out a load capacity analysis and dimensioning of a steel structure of a regulation flap gate at the overflow facility of the Selška Sora high-water reservoir. Steel structure is designed in accordance with DIN 19704 and Eurocode 3 standards and is made of S355J2+N structural steel. The calculation considers the water load under normal operating circumstances.
The gate lifting forces, which have a direct influence on the load bearing capacity of the steel structure have also been analysed and calculated.
The calculation of the steel structure involved an analytical analysis of individual structural elements and a numerical analysis using the PrePoMax software package. In order to determine the gate lifting forces, a multiphase water flow analysis across the flap gate was carried out
Perceived peer support and relationship quality with teachers in relation to the academic engagement and achievement of gifted students
Get PDFNadarjeni učenci so po slovenski zakonodaji učenci, ki izkazujejo visoko nadpovprečne sposobnosti mišljenja ali izjemne dosežke na posameznih učnih področjih, v umetnosti ali športu. Kot taki se torej razlikujejo od učencev, ki niso bili prepoznani kot nadarjeni. Raziskave kažejo, da so nadarjeni učenci v primerjavi z normativnimi bolj zavzeti pri učenju in imajo višje učne dosežke. Za uspešno sodelovanje pri učenju pa vsi učenci potrebujejo različne vrste opore, tako s strani učiteljev kot s strani vrstnikov. Podatki so bili zbrani v okviru projekta Socialni kontekst kot dejavnik medvrstniškega nasilja, ki je bil izveden na 118 slovenskih osnovnih šolah. V naš vzorec smo vključili 6019 učencev, od tega 5030 normativnih učencev (83,57 %) in 989 nadarjenih učencev (16,43 %). Potrdili smo, da so nadarjeni učenci v primerjavi z normativnimi vrstniki učno bolj uspešni in zavzeti. Nadarjeni fantje v primerjavi z normativnimi fanti zaznavajo več vrstniške opore, nadarjena dekleta pa se od normativnih deklet v tem pogledu ne razlikujejo. Nadarjeni učenci v primerjavi z normativnimi poročajo o višji vrednosti pozitivnega vidika kakovosti odnosov z učitelji. Dodatno nadarjeni fantje v primerjavi z normativnimi fanti ter nadarjena dekleta v primerjavi z normativnimi dekleti poročajo o nižji vrednosti negativnega vidika kakovosti odnosov z učitelji. Odkrili smo, da obstaja pozitivna povezava med učno uspešnostjo nadarjenih učencev in pozitivnim vidikom kakovosti odnosa z učitelji. Prav tako pri nadarjenih dekletih obstaja negativna povezava med učno uspešnostjo in negativnim vidikom kakovosti odnosa z učitelji. Tudi učna zavzetost se pri nadarjenih učencih pozitivno povezuje s pozitivnim vidikom kakovosti odnosa z učitelji. Obstaja tudi negativna povezava učne zavzetosti z negativnim vidikom kakovosti odnosa z učitelji in pozitivna povezava učne zavzetosti z zaznano oporo vrstnikov pri nadarjenih. Naša raziskava ponuja uvid v socialne in učne vidike nadarjenih učencev v slovenskem šolskem okolju in lahko služi kot izhodiščna točka za nadaljnje raziskovanje in oblikovanje intervencij z namenom, da bi nadarjeni učenci svoj potencial dosegali v večji meri.According to Slovenian legislation, gifted students are students who display thinking abilities that are highly above the average or exceptional achievements in individual learning areas, in art, or sports. They differentiate as such from the students who are not recognized as gifted. Research show gifted students are more involved in learning and have higher academic achievements compared to normative ones. But to cooperate successfully, all students need various kinds of support such as from teachers as well as from peers. Data has been collected in terms of the project Social Context as the Factor of Peer Violence (Socialni kontekst kot dejavnik medvrstniškega nasilja) which was conducted in 118 Slovenian primary schools. 6019 students were included in the sample, 5030 normative students (83.57%) and 989 gifted students (16.43%). We confirmed that gifted students are didactically more successful and involved compared to normative students. Gifted boys perceive more peer support compared to normative boys, whereas gifted girls do not differentiate from normative girls in this regard. Gifted students report of higher value of the positive aspect of the relationship quality with teachers compared to normative ones. Additionally, gifted boys and gifted girls report lower value of the negative aspect of the relationship quality with teachers compared to normative boys and normative girls. We discovered there is a positive connection between the academic performance of gifted students and the positive aspect of the relationship quality with teachers. There is also a negative connection with gifted girls between academic performance and the negative aspect of the relationship quality with teachers. Academic engagement in gifted students is also positively connected with the positive aspect of the relationship quality with teachers. There is also a negative connection of academic engagement with the negative aspect of the relationship quality with teachers and a positive connection of academic engagement with perceived peer support in gifted students. Our research offers insight into the social and academic aspects of gifted students in a Slovenian school environment and can serve as a starting point in further research and design of interventions with the aim for gifted students to achieve their potential to a greater extent
Designing of transport platforms on a powder coating line
Get PDFV diplomskem delu je predstavljeno konstruiranje transportnih ploščadi/platform na liniji za prašno barvanje. Predstavljena je predelava ogrodij platform iz varjenih na montažne (vijačene) ter preračun nosilnosti kritičnih mest na platformah. Prikazana je tehnična dokumentacija v obliki načrtov. Vse konstruiranje je bilo izvedeno v računalniškem programu Solidworks premium 2022, vse numerične simulacije pa v programu PrePoMax v.2.1.3.The thesis presents the design of transport platforms on a powder coating line. It includes the conversion of platform frames from welded to assembled (bolted) and the load capacity calculation of critical points on the platforms. The technical documentation is shown in the form of plans. All design work was carried out using the computer program Solidworks Premium 2022, and all numerical simulations were performed using the program PrePoMax v.2.1.
Control of a pneumatic manipulator assembly with an industrial controller
Get PDFCilj diplomske naloge je analizirati delovanje in zahteve avtomatizacije pnevmatskega sistema, pripraviti ustrezen krmilni program za zastavljen sistem, ter priklopiti in usposobiti zastavljen sistem. Uporabljen je bil krmilnik "Siemens S7-1200", programiranje in preizkušanje programa pa je potekalo v programu "TIA Portal".The aim of the diploma thesis is to analyze the operation and automation requirements of a pneumatic system, to prepare a suitable control program for the proposed system, and to set up and analyze the working of the program on the system. “Siemens S7-1200” controllers were used, and programming and testing of the program took place in the program “TIA Portal”
MuCoSi virtual clothing collection
Get PDFDiplomsko delo obravnava svilo, svilogojstvo in sviloprejstvo ter kreiranje virtualne kolekcije
oblačil in vzorčastih tekstilij zanjo. Predstavljeno je svilogojstvo in sviloprejstvo v Sloveniji
nekoč in danes in svilna oblačilna dediščina. Na osnovi svilne oblačilne dediščine so
oblikovani vzorci tekstilij za zasnovano kolekcijo oblačil MuCoSi. Zanjo so razviti kroji oblačil
s programsko opremo OptiTex. Kolekcija oblačil je prikazana v virtualnem okolju s pomočjo
vizualiziranih 3D prototipov oblačil.The diploma thesis is focused on silk, silk farming and silk production, and the creation of a
virtual collection of garments and sample textiles for it. It presents silk farming and silk
production in Slovenia, past and present, and silk clothing heritage. Based on the silk
clothing heritage, textile patterns are designed for the MuCoSi clothing collection, for which
clothing patterns are developed using the OptiTex software. The clothing collection is
displayed in a virtual environment with the help of visualised 3D prototypes of the
garments