203 research outputs found
Extraction of chestnut bark with subcritical water
No full textBiomasa predstavlja naravni vir vrednih komponent. Lubje kostanja vsebuje visoke vsebnosti taninov in različne fenolne spojine, ki se uporabljajo v medicini ter farmacevtski, kozmetični in prehrambeni industriji. Namen diplomskega dela je bil separirati vredne spojine iz lubja kostanja s subkritično vodo in optimizirati proces z uporabo metode odzivnih površin z zasnovo Box-Behnkenovega načrtovanja. Optimizirali smo tri ključne spremenljivke, in sicer temperaturo, čas in razmerje topilo/material, ter spremljali njihov vpliv na ekstrakcijski izkoristek in vsebnost vrednih komponent v lubju, kot so totalni fenoli, totalni tanini in antioksidativna aktivnost. V lubju smo dokazali prisotnost elagne in galne kisline, elagotaninov (veskalagin, kastalagin, 1-o-galoj kastalagin), sladkorjev (maltoza, glukoza, fruktoza in arabinoza) ter njihovih derivatov (5-HMF, furfural in levulinska kislina). Zadnji korak v diplomskem delu je bil določitev optimalnih pogojev, s katerimi bi dosegli najvišjo vsebnost elagne kisline ter zadovoljive vsebnosti totalnih fenolov in totalnih taninov.Biomass represents the natural source of valuable compounds. Chestnut bark contains high level of tannins and various phenolic compounds which can be utilized in medicine and pharmaceutical, cosmetic, and food industry. The aim of this work was optimization of subcritical water extraction process of chestnut bark using Box-Behnken response surface method. The influence of process parameters, such as temperature, extraction time and solid-solvent ratio, on extraction yield, yield of the main compounds, total phenol content, total tannin content and antioxidant activity was observed. The identified compounds were ellagic and gallic acid, ellagitannins (vescalagin, castalagin, 1-o-galloyl castalagin), sugars (maltose, glucose, fructose and arabinose) and sugar derivatives (5-HMF, furfural and levulinic acid). The final step of the work was determination of the optimal conditions of the process to obtain the bark extract highly rich in ellagic acid and with satisfactory level of total phenols and total tannins
Reactive CO 2 absorption in mixtures of ionic liquids and ethanolamine
No full textV zadnjem stoletju so človekove dejavnosti v ozračje izpustile velike količine CO2 in drugih dimnih plinov, ki so posledica globalno segrevanje. To lahko s časom vpliva na zaloge vode, na okolje, na naše zdravje in varnost.
Odstranjevanje emisij CO2 iz dimnih plinov je zelo pomembno s stališča narave in nam predstavlja velik izziv. Procesi za odstranjevanje CO2 iz dimnih plinov temeljijo na kemijski in fizikalni absorpciji v tekočinah.
Etanolamin je najbolj pogost amin za zamreževanje CO2. Velik potencial za zamreževanje CO2 iz dimnih plinov pa prikazujejo tudi ionske tekočine, zaradi njihovih unikatnih lastnosti, kot so stabilnost v velikem temperaturnem razponu, nehlapnost in visoko tališče, ki se kaže s toplotno stabilnostjo.
Namen diplomskega dela je bil osredotočen na možno uporabo mešanic etanolamina in ionskih tekočin kot sredstvo za zamreženje CO2. Ta proces je prvič zasnoval Camper s sodelavci, ko je predlagal mešanje ionskih tekočin s skomercializiranimi amini.
V eksperimentalnem delu smo mešanice vode in etanolamina primerjali z mešanicami ionskih tekočin in etanolamina, po tem, ko smo jim dodali CO2. Spremembe temperatur vzorcev smo med procesom opazovali in jih na koncu primerjali. Za nadaljno karakterizacijo smo uporabljali Fourirerjevo transformacijsko infrardečo spektroskopijo (FTIR).For the past century human activities have released large amounts of CO2 and other greenhouse gases into the atmosphere. These gases are held responsible for global warming. With time, these changes can affect water supplies, natural environment, health and safety.
From the environmental point of view reducing the greenhouse gas emissions of CO2 is very important and it presents an enormous challenge. Processes for removing CO2 from flue gases are based on chemical or physical absorption in liquids. Mono-ethanolamine (MEA) is the most commonly used amine for CO2 capture. Ionic liquids have shown great potential for capturing CO2 from flue gases, because of their unique characteristics such as chemical stability over a wide range of temperatures, low volatility, and high melting points, thus providing thermal stability.
The aim of this work was focused on the possibility of using MEA - ionic liquids’ solutions as solvents for capturing CO2. This approach was first initiated by Camper et.al, who suggested mixing room temperature ionic liquids (RTILs) with commercial amines.
During the experimental section, aqueous MEA solutions were compared with MEA in ionic liquids’ solutions, whilst CO2 was added to the mixtures. The changes in temperatures of the samples were observed and compared. For further characterization Fourier Transform Infra-Red spectroscopy (FTIR) was carried out
PLANNING THE OPERATION AND BEHAVIOUR IN A TRADING COMPANY
No full textPlaniranje je del našega vsakdana. Kot je planiranje prisotno v vsakdanjem življenju pri preprostih opravilih, tako je prisotno pri kompleksnejših odločitvah v podjetjih. S planiranjem se v podjetju srečujemo vse od njegovega nastajanja – ustanovitve, razvoja in rasti, delovanja in obnašanja, samega poslovanja, sanacije in ne nazadnje tudi prenehanja podjetja. Z dobrim planiranjem v času obstoja in razvoja, ter delovanja in obnašanja se znatno podaljša življenjska doba podjetja in se prepreči sanacija.
V diplomskem delu smo preučevali trgovsko podjetje in presojali planiranje delovanja in obnašanja v podjetju. Trgovsko podjetje je specializirana trgovina na debelo na področju pekarstva, slaščičarstva in gostinstva. Podjetje spada po Zakonu o gospodarskih družbah med majhne družbe. V začetnem delu diplomskega dela smo na splošno opredelili podjetniško planiranje, delovanje in obnašanja v podjetju. V nadaljevanju diplomskega dela smo predstavili trgovsko podjetje, njegovo vizijo in poslanstvo ter temeljne cilje. V obravnavanem podjetju smo ugotavljali in preučevali planiranje, področja planiranja in planiranje angažiranja. Ugotovili smo prednosti in slabosti ter priložnosti in nevarnosti v podjetju in zunaj njega. Menimo, da je največja prednost kakovost prodajnega blaga in dobro poznavanje prodajnih trgov. Največjo slabost pa smo zaznali v veliki koncentraciji domače in tuje konkurence.
Na podlagi analiziranja trgovskega podjetja smo opozorili na nekaj področji, v katerih planiranje ni najbolj optimalno. S tem smo podjetju pripomogli k še boljšemu planiranju delovanja in obnašanja ter posledično k boljšemu poslovnemu rezultatu.Planning is a part of a daily life. The same way it is present in a daily life, it is also present in more complex decisions in a company. We apply planning in the company at its formation – establishment, development and growth, operation and behaviour, remediation and even at the dissolution of the company. The lifespan of the company significantly extends with good planning during the business’s existence and development, operation and behaviour, and also prevents the need for the remediation of the company.
In this thesis, I studied the trading company and its planning of the operation and behaviour of the company. The trading company is a wholesaler specialized in the bakery, confectionery and catering industry. This company is classified as a small business, according to the Companies Act. In the first part of the thesis, I roughly describe company’s planning and operation, and behaviour in it. In the second part of the thesis, I present the trading company, its vision, mission and primary goals. In the case company, I observed and studied the planning, areas and engagement of planning. I determined advantages and disadvantages and also opportunities, and internal and external threats. The biggest advantage of this company is the quality of the goods they sell and good knowledge of the markets. The biggest threat I was able to determine, was the high concentration of domestic and foreign competitors.
Based on the analysis of the trading company, I was able to point out the areas, where planning was not optimised. With this I helped the company to a better planning and behaviour, and consequently to the better business result
READINESS OF KINDERGARTEN TEACHERS TO GIVE FIRST AID IN THE KINDERGARTEN
No full textPri vsakdanjem delu v vrtcu se strokovni delavci poleg načrtovanega vzgojnega dela srečujejo tudi s poškodbami in nenadnimi bolezenskimi stanji. Namen diplomskega dela je bil ugotoviti, ali so strokovni delavci sposobni ustrezno nuditi prvo pomoč otroku. Za namen raziskave smo uporabili anketni vprašalnik, ki je vseboval 26 vprašanj. S pomočjo vprašalnika se je raziskalo, s katerimi poškodbami in nenadnimi bolezenskimi stanji se najpogosteje srečujejo vzgojitelji in pomočniki vzgojiteljev v praksi ter za katere jih je najbolj strah, da bi do njih prišlo v njihovi skupini. V raziskavi je sodelovalo 72 anketiranih vzgojiteljic in pomočnic vzgojiteljic na območju Dolenjske. Podatke smo obdelali kvantitativno z deskriptivno statistiko, s frekvenčno distribucijo, z uporabo tabel in z grafičnim prikazom. Raziskava je pokazala, da so strokovni delavci v vrtcih delno sposobni nuditi ustrezno prvo pomoč v določenih situacijah. Znanje prve pomoči strokovnih delavcev bi se moralo izpopolnjevati in obnavljati v krajšem obdobju.In addition to the planned educational work, early childhood professionals also face injuries and sudden health conditions with children in kindergartens. The objective of the diploma paper was to find whether early childhood professionals are able to properly offer first aid to children. We conducted a study with a questionnaire comprising 26 questions. The questionnaire helped us to analyse what injuries and sudden health conditions kindergarten teachers and their assistants encounter most frequently and which of those they are most afraid would occur in their groups. Our study included 72 kindergarten teachers and assistants in the Dolenjska region. The data obtained was processed quantitatively with descriptive statistics, using a frequency distribution, charts and graphs. The study has shown that early childhood professionals are partly able to properly offer first aid in certain situations. First aid knowledge among early childhood professionals should be extended and renewed over a shorter period of time
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