The objective of this study is to extract phenolic compounds from nettle and melissa by using microwave and ultrasound and to compare these methods with conventional extraction and maceration, respectively. Extraction of melissa essential oil was also studied. In extraction of phenolics, effects of extraction time (5-20 min for microwave / 5-30 min for ultrasound) and solid to solvent ratio (1:10, 1:20, 1:30 g/ml) on total phenolic content (TPC) were investigated for microwave and ultrasound extractions. Different powers were also studied for ultrasound extraction. In addition, effect of solvent type (water, ethanol, ethanol-water mixture at 50:50 v/v) was analyzed and water was found as better solvent. Optimum conditions for microwave extraction of phenolics were determined as 10 min and 1:30 solid to solvent ratio for nettle, and as 5 min and 1:30 solid to solvent ratio for melissa. TPC at these conditions for nettle and melissa extracts were 24.6 and 145.8 mg GAE/g dry material, respectively. Optimum conditions for ultrasound extraction was 30 min, 1:30 solid to solvent ratio, and 80% power for nettle and 20 min, 1:30 solid to solvent ratio, and 50% power for melissa. TPC at these conditions for nettle and melissa were 23.9 and 105.5 mg GAE/g dry material, respectively. Major phenolic acids were determined as naringenin in nettle and rosmarinic acid in melissa. Major aromatic compounds in melissa essential oil were found as limonene, citral, and caryophyllene oxide. Yields of essential oil obtained by microwave and hydrodistillation were 4.1 and 1.8 mg oil/g dry sample, respectively.

Fibre plants favour different growth conditions and require different levels of husbandry. However, the fibres share some physical and material properties, which make them difficult to distinguish in the archaeological record. This thesis evaluates the effectiveness of methods for characterising bast fibres including; fibre chemical analysis, mechanical testing and fibre morphology, to propose that longitudinal microfibrillar angle (MFA) and cross-sectional circularity (Ct) used in a two-step procedure to analyse selected modern fibres of nettle (Urtica dioica L.), flax (Linum usitatissimum L.) and hemp (Cannabis sativa L.) could offer an alternative approach. The reliability of MFA and Ct, as diagnostic features, was evaluated under a temperature accelerated degradation 48week trial with eight fibre types from three deposition soils Post deposition, surviving fibres were subjected to evaluation of changes in MFA and Ct. An additional check on the diagnostic efficacy was conducted within a blind-test protocol. Finally, the research programme employs MFA and Ct in the diagnosis of a range of archaeological textile fibres from museum collections and fibres from the Kasr el Yahud mass burial. The thesis includes recommendations to address future post thesis research programmes.

The aim of this esseay is to analyse the configuration of the literary child in Henning Mankells Comedia Infantil and Harry Martinssons Flowering Nettle. The teoretical outset is interdisciplinary, informed by both literarystudies and childstudies adopting a psycho-social perspective which allows a reading of the childprotagonists inside as well as outside preconditions and how these are constructed in the texts. The narratological concepts of focalization is used to investigate in detail how the narrator and narrative constructs a childperspectiveand conception of childhood. A point of interest is also to examine how the novels relate to the idea of the innocent or/and the competent child.

No description available.

The plant Urera baccifera Gaudich, known as stinging nettle, had its leaves and roots used to urinary infections and arthritis. Studies about its anti-inflammatory activities already exist, but are few the studies about their chemical constituents. Due the shortage of dates, this study aim to realize an qualitative and quantitative photochemistry analysis, and antioxidant activity of the plant roots and leaves, beyond realize a morphoanatomic and hystochemical study its leaves and stems. In the qualitative analysis were obtained positive results to aminogroups, anthocyanins, anthocyanidins and flavonoids, steroids, phenols with free para positions, coumarins, saponins and organic acids in the leaves and the roots. In the qualitative analysis the plant showed significant values of phenolic compounds, flavonoids, alkaloids and condensed tannins, mainly in the chloroform fraction of leaves and roots. The crude extract of both part of the plant presented a moderated antioxidant activity. An expressive concentration of oxalic acid was quantified in the roots, indicating toxicity. The morphological analysis of steams and leaves showed stinging, simple tectores and glandular trichomes, cistolits in the epidermis and abundant presence of drusen-type crystals of calcium oxalate besides that elucidate the inner structure of the plant tissues. In the hystochemical tests were presented in the different vegetative organs, substances which form cell walls, reserve substances and secondary metabolites, like phenolic compounds, lipids, terpenoids and cetosteroids, tannins and serotonin. More studies will be realized with Urera baccifera roots, stems and leaves, to elucidate its chemical composition and toxic potential. / A planta Urera baccifera Gaudich, conhecida como Urtiga-Brava, tem suas folhas e raízes utilizadas para infecção urinária e artrite. Já existem estudos sobre sua atividade antiinflamatória, mas poucos são os estudos a respeito de sua composição química. Devido à escassez de dados, este estudo visa realizar uma análise fitoquímica qualitativa e quantitativa, e avaliar a atividade antioxidante das raízes e folhas da planta, além de realizar um estudo morfo-anatomico e histoquímico das folhas e caules. Na análise qualitativa foram obtidos resultados positivos para aminogrupos, antocianinas, antocianidinas e flavonóides, esteróides, fenóis com posição para livres, cumarinas, saponinas e ácidos orgânicos nas folhas e raízes. Na analise qualitativa a planta mostrou valores significantes de compostos fenólicos, flavonoides, flavonóis, alcaloides e taninos condensados principalmente na fração clorofórmio das folhas e raízes. O extrato bruto das duas partes da planta demonstraram uma moderada atividade antioxidante. Foi quantificado numa concentração expressiva, ácido oxálico nas raízes, indicando toxicidade. A análise da morfologia dos caules e folhas evidenciou tricomas urticantes, tectores simples e glandulares, cistólitos na epiderme e presença abundante de cristais do tipo drusas de oxalato de cálcio, além de elucidar a estrutura interna dos tecidos da planta. Nos testes histoquímicos foram evidenciados nos diferentes órgãos vegetativos, substâncias que formam as paredes celulares, substâncias de reserva e metabólitos secundários, como compostos fenólicos, lipídios, terpenóides e cetoesteróides, taninos e serotonina. Mais estudos serão realizados com raízes, caules e folhas de Urera baccifera, a fim de elucidar sua composição química e analisar seu potencial tóxico.

No description available.

Tyrimo tikslas – įvertinti skirtingo natūralaus pluošto įtaką kompozicinės medžiagos polietilenas – pluoštas“ mechaninėms savybėms. Bandinių gamyba bei medžiagų mechaninių savybių tyrimai atlikti 2013/2014 m. Aleksandro Stulginskio universitete, Jėgos ir transporto mašinų inžinerijos instituto ir Žemės ūkio inžinerijos ir saugos instituto laboratorijose. Tyrinėjami kompozitai armuoti trimis skirtingai natūraliais pluoštais: kanapių, dilgėlių ir linų. Polietileno klijų kompozitas armuojamas keturiais kiekiais pluošto: 5 %,7 %, 10 % ir12 %. Tempimo ir lenkimo bandymai atlikti „Instron“ medžiagų savybių tyrimo stendu, nustatyta apkrova, kurią atlaiko bandinys ir deformacija. Atlikus lenkimo ir tempimo tyrimus nustatyta, kad geriausia armuojanti medžiaga yra kanapių pluoštas. Tempiant atlaikė didžiausią apkrovą – 753,7 N ir deformavosi 4 mm. Lenkiant kanapių pluoštu armuotas bandinys atlaikė 24,3 N apkrovą ir deformavosi 11,6 mm. / The aim - to evaluate the influence of different natural fiber composite polyethylene - fibers' mechanical properties. Specimen fabrication and mechanical properties of the materials were tested in 2013/2014 year. Alexander Stulginskio University, Power and Transport Machine Engineering and the Institute of Agricultural Engineering and Safety Institute laboratories. Reinforced composites are studied in three different natural fibers: hemp, ramie and flax. Polyethylene adhesive composite reinforced with four volumes of fiber: 5%, 7%, 10%, and 12%. Tensile and flexural tests were examined by using "Instron" material properties testing machine down load the sample and can withstand deformation. After bending and tensile tests showed that the best reinforcement material is hemp. Tensile withstood the maximum load - 753.7 N and deformed 4 mm. bending of hemp fiber reinforced sample withstood 24.3 N load and 11.6 mm.

Tyrimai atlikti 2012 – 2013 metais ASU Žemės ūkio inžinerijos ir saugos instituto laboratorijose bei ASU bandymų stotyje. Darbo tikslas – ištirti netradicinių energetinių augalų (drambliažolių, pluoštinių kanapių ir pluoštinių dilgėlių) ruošimo ir naudojimo biokurui technologinius-techninius parametrus bei nustatyti susmulkintų ir supresuotų augalų fizikines-mechanines savybes ir kokybinius rodiklius. Pateikto darbo literatūros apžvalgoje išanalizuota šių augalų nuėmimo ir paruošimo technologija biokurui bei įvertintos augalų naudojimo deginimui galimybės. Atlikus drambliažolių, pluoštinių kanapių ir pluoštinių dilgėlių eksperimentinius tyrimus buvo nustatyti biometriniai rodikliai, smulkinimo ir malimo parametrai, ištirtos pjaustinio ir miltų fizikinės-mechaninės savybės. Nustatyta frakcinė sudėtis pagal ES šalyse taikomą metodiką, naudojant sietų komplektą su skirtingų skersmens skylutėmis. Taip pat buvo ištirtos ir paruoštų granulių svarbiausios fizikinės-mechaninės savybės. / Investigations were carried out in 2012-2013 years in the laboratories of ASU Institute of Agricultural Engineering and Safety and ASU training farm. The aim – to investigate the technological-technical parameters of non-traditional energy plants (elephant grass, fibrous hemp and fibrous nettle) for the preparation and use of biofuels and to determine the chopped and pressed plant physical-mechanical properties and qualitative indicators. In the literature review of presented work was analyzed the plant harvesting and processing technology of biofuels and evaluates the use of plants burning capabilities. After the elephant grass, fibrous hemp and fibrous nettle experimental studies were established the biometric indicators, chopping and milling parameters, and were investigated the chaff and mill physical-mechanical properties. Fractional composition was determined according to the methodology of EU countries, while using the sieves with the different diameter holes. It was also been tested and most important physical-mechanical properties of prepared pellets.

<p>U ovoj disertaciji proučavana je osmotska<br />dehidratacija lista koprive u dva različita<br />osmotska rastvora: 1. vodenom rastvoru<br />saharoze i natrijum hlorida i 2. melasi &scaron;ećerne<br />repe. Ispitivan je uticaj temperature procesa<br />(20&deg;C, 35&deg;C i 50&deg;C) i vremena imerzije (30, 60<br />i 90 min) na gubitak vode, prira&scaron;taj suve<br />materije, sadržaj suve materije, vrednosti<br />aktivnosti vode, mikrobioo&scaron;ke promene,<br />promenu mineralnog sastava (Ca, Mg, Na, K,<br />Fe, Cu, Zn, Mn, Co) i promenu antioksidativne<br />aktivnosti, tokom osmotske dehidratacije lista koprive.<br />Dokazano je da se povećanjem temperature i<br />produženjem vremena trajanja procesa<br />pospe&scaron;uje prenos mase tj. migracija molekula<br />vode iz tretiranog biljnog materijala u okolni<br />rastvor, i prodiranje molekula rastvorene<br />supstance iz osmotskog rastvora u tretirano<br />biljno tkivo.<br />Snižene aw vrednosti u svim ispitivanim<br />uzorcima ukazuju na pozitivan uticaj osmotske<br />dehidratacije na mikrobiolo&scaron;ku stabilnost<br />tretiranog lista koprive. Dobijeni rezultati su<br />pokazali značajno pobolj&scaron;anje mineralnog<br />sastava lista koprive, dehidriranih u melasi<br />&scaron;ećerne repe, dok je kod uzoraka tretiranih u<br />rastvoru saharoze i natrijumhlorida uočeno<br />smanjenje sadržaja ispitivanih mineralnih<br />materija. Nasuprot rastvoru saharoze i natrijum<br />hlorida koji je uticao na opadanje ukupne<br />antioksidativnosti osmotski dehidriranih<br />uzoraka, melasa &scaron;ećerne repe, kao bogat izvor<br />prirodnih antioksidanasa, doprinosi povećanju<br />antioksidativnosti i pobolj&scaron;anju funkcionalnog<br />kvaliteta dehidriranog produkta.<br />Statističkom obradom rezultata, uočeno je da<br />su optimalni procesni parametri u pogledu<br />efikasnosti procesa, kao i mikrobiolo&scaron;kog,<br />nutritivnog i funkcionalnog kvaliteta osmotski<br />dehidriranog lista koprive, vreme trajanja<br />procesa od 60 min, na temperaturi od 50&deg;C, u<br />melasi &scaron;ećerne repe kao osmotskom rastvoru.</p> / <p>The osmotic dehydration of the nettle leaf into<br />two different osmotic media was studied in this<br />dissertation: 1. Aqueous solution of sucrose and<br />sodium chloride and 2. Sugar beet molasses.<br />The effects of the process temperature (20 &deg;C,<br />35 &deg;C and 50 &deg;C) and the immersion time (30,<br />60 and 90 min) on water loss, solid gain, dry<br />matter content, water activity, microbial<br />changes, mineral composition (Ca, Mg, Na, K,<br />Fe, Cu, Zn, Mn, Co) and the change in the antioxidant activity during osmotic dehydration<br />of the nettle leaf were studied in this<br />investigation.<br />It has been proved that the increase in<br />temperature and the prolonging of process time,<br />accelerate the mass transfer, i. e., the migration<br />of the water molecules from the treated plant<br />material to the surrounding osmotic solution,<br />and also the penetration of the molecules from<br />the osmotic solution into the treated plant tissue.<br />The reduced aw values in all tested samples<br />indicate the positive effect of osmotic<br />dehydration on the microbiological stability of<br />the treated nettle leaf. The obtained results<br />showed a significant improvement in the<br />mineral composition of the nettle leaf<br />dehydrated in sugar beet molasses, while the<br />decrease in the mineral content was observed in<br />the samples treated with sucrose and sodium<br />chloride solution. Contrary to the sucrose and<br />sodium chloride solution, which negatively<br />affected the overall antioxidative effect of<br />osmotically dehydrated samples, sugar beet<br />molasses contributed to an increase in<br />antioxidantity, being a rich source of natural<br />antioxidants, and it also improves the functional<br />quality of the dehydrated product.<br />Statistical analysis of the obtained experimental<br />results showed that optimal process parameters<br />in terms of process efficiency, as well as<br />microbiological, nutritive and functional quality<br />of the osmotically dehydrated leaf net, could be<br />reached after 60 min of osmotic treatment, at a<br />temperature of 50 &deg;C, using sugar beet molasses<br />as an osmotic solution.</p>