557 resultados para Assignments


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There are NMR data of ¹H and 13C of the iridoid plumieride, but controversy related to the assignments of the protons H-3 or H-10 and carbons C-6 or C-7 and C-3 or C-10 are described in the literature. There are a little discussion regarding to the resonance assignment of protons of the glycoside unity. Analysis based on 2D shift correlated NMR spectra (COSY, HETCOR, HETCORLR) and NOE difference ¹H NMR spectra allowed to assign unambigously the chemical shift of ¹H and 13C of plumieride which has been found in the literature with non coincident values.

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Phytochemical investigation of the leaves and branches of a specimen of Ouratea semiserrata led to the isolation and characterization of ent-16alpha,17-dihydroxykauran-19-oic acid, along with other natural products. This diterpenoid and its derivatives were used to unambiguous ¹H and 13C chemical shifts assignments and to indicate some mistake data described in the literature as consequence mainly of the stereochemicals of the chiral carbons C-4 and C-16. The HRMS spectra were also analysed.

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The flowers of Stiffitia chrysantha Mikam(Asteraceae) contain eriodictiol, quercetin, luteolin and b-D-glycopyranosil-sitosterol. These compounds and its derivatives were identified by their 1H and 13C NMR, infra-red and mass spectra data. The heteronuclear 2D NMR were used to confirm the assignments of the proton and carbon chemical shifts, it was used to eliminate definitively the ambiguous correlation reported in the literature for C-5 and C-9 of quercetin and C-23 and C-25 of b-D-glycopyranosil-sitosterol.

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Työn tavoitteena on sisäisen palveluyksikön prosessikuvauksien kautta kehittää nykyistä toimintaa, laskea tuotettujen palveluiden yksikkökustannuksia ja arvioida palkitsemisen vaikutusta sisäisten tukipalveluiden tuottamisen tehostamiseen Nurmijärven kunnassa. Toimintolaskennalla saadaan aikaiseksi tuotetuille palveluille kustannukset ja tuotehinnoittelu. Tällä saadaan aikaan lähes aiheuttamisperiaatteen mukainen kustannusten kohdistaminen. Lisäksi työssä arvioidaan kustannusten kautta saavutettavaa toiminnan tehokkuutta. Työssä haastateltiin yksikön henkilökuntaa, minkä tuloksena saatiin toiminnasta prosessikuvaukset. Toimintolaskennassa tiedot kerättiin eri järjestelmistä ja yksikössä mitattiin työtehtävien hoitoon käytettyä aikaa. Kannusteiden vaikutuksista järjestettiin kolmen organisaation tietotekniikkayksiköiden henkilökunnalle kysely sekä yksikön esimiehet haastateltiin. Haastattelun avulla selvitettiin palkitsemisen nykytilannetta ja tulevaisuuden kehittämismahdollisuuksia. Tuloksena saatiin tukipalveluhinnasto, jolla toteutettiin sisäisten kustannusten kohdistaminen organisaatiossa. Tukipalveluprosessien kuvaamisen tuloksena saatiin toimenpide-ehdotuksia toteutukseen ja lisäkehittämishankkeita. Työntekijöiden kannustekyselyn tuloksena rahapalkitsemisen lisäksi nousi esiin esimiehen antaman palautteen arvostus sekä oman osaamisen kehittäminen.

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Suomessa asuu haja-asutusalueilla yli miljoona ihmistä, jotka käyttävät kiinteistökohtaista jätevesijärjestelmää. Arviolta 350 000-400 000 kiinteistöä joutuu saneeraamaan järjestelmänsä vuoden 2013 loppuun mennessä vastaamaan Valtioneuvoston asetusta. Jätevesijärjestelmän korjaamiseen tarvitaan yleensä toimenpidelupa ja sen liitteeksi suunnitelma jätevesien käsittelystä. Suunnittelu- ja toteutusprosessin tietohallintaan tarvitaan tietojärjestelmä. Diplomityössä perehdyttiin tietokantapohjaisiin Internet-sovelluksiin ja ekstranet-järjestelmiin ja suunniteltiin niiden perusteella käyttökelpoisin tietojärjestelmäratkaisu, jonka avulla jätevesialan toimijat voivat jakaa tietoa, tehdä jätevesiselvityksiä ja -suunnitelmia, välittää toimeksiantoja aliurakoitsijoille ja raportoida tietoja viranomaisille sähköisesti. Työn tuloksena syntyi selvitys tietojärjestelmän suunnittelun pohjaksi, ja suunnitelma järjestelmän toteuttamiseksi. Järjestelmällä voidaan tarjota asiakkaalle eli kiinteistönomistajalle kokonaisvaltainen ratkaisu jätevesijärjestelmän saneeraukseen ja ylläpitoon.

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There is no question that students majoring in chemistry graduate with underdeveloped writing skills. Many educators have expressed concern about the obvious deficiencies in student writing. This article is designed to aid professors interested in teaching writing skills in their classrooms and laboratories.

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The structures of seven oleanene and ursene triterpenoids (1-7) isolated from aerial parts of Mentha villosa were identified. In addition, the complete ¹H and 13C resonance assignments of these triterpenoids were accomplished using 1D and 2D NMR spectroscopic experiments.

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Harjoitustöiden vertaisarvioinnissa opiskelijat tarkastavat toistensa töitä ja antavat niistä palautteen annettujen ohjeiden mukaan. Yleensä opiskelijoille annetaan tätä tehtävää tukemaan tietty joukko arviointikriteereitä, joiden osalta työtä ainakin on kommentoitava. Vertaisarviointi voi antaa opiskelijoille monipuolisempaa palautetta kuin ilman sitä olisi mahdollista, mahdollisuuden tehtävien vaihtoehtoisiin ratkaisuihin tutustumiseen sekä kokemusta ongelmanratkaisun analyyttisestä ja kriittisestä tarkastelusta. Lisäksi vertaisarviointi voi tukea opettajien työtä helpottamalla riittävän palautteen antamista opiskelijoille ja antamalla jonkinlaista kuvaa opiskelijoiden näkemyksistä tehtävän aihealueeseen liittyen. Tämän työn tavoitteena on selvittää, mitä mainituista vertaisarviointiin liitetyistä hyödyistä voidaan todellisuudessa saavuttaa ohjelmointipainotteisilla kursseilla. Ohjelmointikurssin opiskelijat arvioivat kurssiin kuuluvien harjoitustöiden yhteydessä toistensa ratkaisuja yhteen tehtävistä. Opiskelijoille suunnatulla kyselyllä pyritään kartoittamaan, kuinka hyvin vertaisarvioinnille asetetut tavoitteet toteutuvat. Kokemuksia opettajan näkökulmasta selvitetään haastattelujen avulla. Testauksen toteutuksessa käytetään verkkosovellusta, johon opiskelijat tallentavat omat työnsä, josta he lataavat itselleen määrätyt työt arvioitavaksi, johon he tallentavat arvionsa ja jonka kautta he lopulta saavat palautteen omasta työstään.

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In an ethanolic extract of leaves of Ottonia corcovadensis (Piperaceae) were identified sixteen terpenoids of essential oil and the three flavonoids 3',4',5,5',7-pentamethoxyflavone (1), 3',4',5,7-tetramethoxyflavone (2) and 5-hydroxy-3',4',5',7-tetramethoxyflavone (3) and cafeic acid (4). Two amides (5 and 6) were isolated from an ethanolic extract of the roots. The structures were established by spectral analysis, meanly NMR (1D and 2D) and mass spectra. Extensive NMR analysis was also used to complete ¹H and 13C chemical shift assignments of the flavonoids and amides. The components of the essential oil were identified by computer library search, retention indices and visual interpretation of mass spectra.

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Four different pseudopotentials and three methodologies were employed in the calculation of the geometry and the frequencies of metal complexes like [M(NH3)2X2] [X=halogen, M=Zn, Cd], and [Hg(NH3)2]Cl2. The vibrational assignments were carefully checked and compared to the theoretically calculated ones. Graphical procedures were employed to estimate family errors and their average behavior. The calculated results show the SBK-X basis set with the best results for the geometries and calculated frequencies, for individual species and statistical results. Its use is recommend, mainly if the neighborhood atoms are described with similar pseudopotentials. Excellent results were also obtained with the Hay and Wadt pseudopotential.

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Phytochemical studies with leaves of Uncaria guianensis resulted in the isolation of the oxindole alkaloids isomitraphylline (1), 3-isoajmalicine (2) mitraphylline (3), and isomitraphylinic acid (4). Structural assignments of these alkaloids, including relative configurations and conformations, were performed through spectral data and physical properties. 1D and 2D homonuclear and heteronuclear NMR spectroscopy was a valuable tool for the establishment of the relative stereochemistry of those compounds.

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The ¹H NMR data set of a series of 3-aryl (1,2,4)-oxadiazol-5-carbohydrazide benzylidene derivatives synthesized in our group was analyzed using the chemometric technique of principal component analysis (PCA). Using the original ¹H NMR data PCA allowed identifying some misassignments of the proton aromatic chemical shifts. As a consequence of this multivariate analysis, nuclear Overhauser difference experiments were performed to investigate the ambiguity of other assignments of the ortho and meta aromatic hydrogens for the compound with the bromine substituent. The effect of the 1,2,4-oxadiazol group as an electron acceptor, mainly for the hydrogens 12,13, has been highlighted.

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The research assesses the skills of upper comprehensive school pupils in history. The focus is on locating personal motives, assessing wider reasons hidden in historical sources and evaluating source reliability. The research also questions how a wide use of multiple sources affects pupils’ holistic understanding of historical phenomena. The participants were a multicultural group of pupils. The origins of their cultures can be traced to the Balkan, the Middle East, Asia and Europe. The number of native Finnish speakers and pupils speaking Finnish as their second language was almost equal. The multicultural composition provides opportunities to assess how culturally responsive learning history from sources is. The intercultural approach to learning in a multicultural setting emphasizes equality as a precondition for learning. In order to set assignments at least to some extent match with all participants only those answers were taken into account which were produced by pupils who had studied history for a similar period of time in the Finnish comprehensive school system. Due to the small number of participants (41), the study avoids wide generalizations. Nevertheless, possible cultural blueprints in pupils’ way of thinking are noted. The first test examined the skills of pupils to find motives for emigration. The results showed that for 7th graders finding reasons is not a problematic task. However, the number of reasons noticed and justifications varied. In addition, the way the pupils explained their choices was a distinguishing factor. Some pupils interpreted source material making use of previous knowledge on the issue, while other pupils based their analysis solely on the text handed and did not try to add their own knowledge. Answers were divided into three categories: historical, explanatory and stating. Historical answers combined smoothly previously learned historical knowledge to one’s own source analysis; explanatory answers often ignored a wider frame, although they were effective when explaining e.g. historical concepts. The stating answers only noticed motives from the sources and made no attempts to explain them historically. Was the first test culturally responsive? All pupils representing different cultures tackled the first source exam successfully, but there were some signs of how historical concepts are understood in a slightly different way if the pupil’s personal history has no linkage to the concepts under scrutiny. The second test focused on the history of Native Americans. The test first required pupils to recognize whether short source extracts (5) were written by Indians or Caucasians. Based on what they had already learned from North American history, the pupils did not find it hard to distinguish between the sources. The analysis of multiphase causes and consequences of the disputes between Native Americans and white Americans caused dispersion among pupils. Using two historical sources and combining historical knowledge from both of them simultaneously was cumbersome for many. The explanations of consequences can be divided into two groups: the ones emphasizing short term consequences and those placing emphasis on long term consequences. The short term approach was mainly followed by boys in every group. The girls mainly paid attention to long term consequences. The result suggests that historical knowledge in sources is at least to some extent read through role and gender lenses. The third test required pupils to explain in their own words how the three sources given differed in their account of living conditions in Nazi Germany, which turned out to be demanding for many pupils. The pupils’ stronghold was rather the assessment of source reliability and accounts why the sources approached the same events differently. All participants wrote critical and justified comments on reliability and aspects that might have affected the content of the sources. The pupils felt that the main reasons that affected source reliability were the authors’ ethnic background, nationality and profession. The assessment showed that pupils were well aware that position in a historical situation has an impact on historical accounts, but in certain cases the victim’s account was seen as a historical truth. The account of events by a historian was chosen most often as the most reliable source, but it was often justified leniently with an indication to professionalism rather than with clear ideas of how historians conduct accounts based on sources. In brief, the last source test demonstrates that pupils have a strong idea that the ethnicity or nationalism determines how people explained events of the past. It is also an implication that pupils understand how historical knowledge is interpretative. The results also imply that history can be analyzed from a neutral perspective. One’s own membership in an ethnical or religious group does not automatically mean that a person’s cultural identity excludes historical explanations if something in them contradicts with his or her identity. The second method of extracting knowledge of pupils’ historical thinking was an essay analysis. The analysis shows that an analytical account of complicated political issues, which often include a great number of complicated political concepts, leads more likely to an inconsistent structure in the written work of pupils. The material also demonstrates that pupils have a strong tendency to take a critical stance when assessing history. Historical empathy in particular is shown if history somehow has a linkage to young people, children or minorities. Some topics can also awake strong feelings, especially among pupils with emigrant background, if there is a linkage between one’s own personal history and that of the school; and occasionally a student’s historical experience or thoughts replaced school history. Using sources during history lessons at school seems to have many advantages. It enhances the reasoning skills of pupils and their skills to assess the nature of historical knowledge. Thus one of the main aims and a great benefit of source work is to encourage pupils to express their own ideas and opinions. To conclude, when assessing the skills of adolescents in history - their work with sources, comments on history, historical knowledge and finally their historical thinking - one should be cautious and avoid cut off score evaluations. One purpose of pursuing history with sources is to encourage pupils to think independently, which is a useful tool for further identity construction. The idea that pupils have the right to conduct their own interpretations of history can be partially understood as part of a wider learning process, justification to study history comes from extrinsic reasons. The intrinsic reason is history itself; in order to understand history one should have a basic understanding of history as a specific domain of knowledge. Using sources does not mean that knowing history is of secondary importance. Only a balance between knowing the contextual history, understanding basic key concepts and working with sources is a solid base to improve pupils’ historical understanding.

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Tiedostojen palautus erilaisissa kursseissa yleistyy. Harjoituksia ja harjoitustöitä palautetaan erilaisissa tiedostomuodoissa, yleensä sähköpostin välityksellä. Oppilaat saattavat palauttaa tiedostoja väärin nimettynä tai tiedostotyyppi on väärä, joka hankaloittaa tarkastusta. Oppilas määrän ollessa suuri, tulee palautuksia myös paljon, joka täyttää tarkastajan sähköpostin. Tämän kandidaatintyön tarkoitus on selventää mitkä ohjelmointikielet kävisivät verkkopohjaisen palautusjärjestelmän toteutukseen. Verkkopohjainen palautusjärjestelmä toteutetaan kirjallisuudesta löytyvän materiaalin perusteella.

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Six known alkaloids iboga type and the triterpen α- and β-amyrin acetate were isolated from the roots and stems of Peschiera affinis. Their structures were characterized on the basis of spectral data mainly NMR and mass spectra. 1D and 2D NMR spectra were also used to unequivocal ¹H and 13C chemical shift assignments of alkaloids. The ethanolic extract of roots, alkaloidic and no-alkaloidic fractions and iso-voacristine hydroxyindolenine and voacangine were evaluated for their antioxidative properties using an autographic assay based on β-carotene bleaching on TLC plates, and also spectrophotometric detection by reduction of the stable DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical.