842 resultados para FORM-I


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Yellow form (I): Mr= 350.09, monoclinic, P2Jn, Z--4, a=9.525(1), b=14.762(1), c= 11.268(1),/t, fl= 107.82 (1) o , V= 1508.3 A 3 , Din(flotation in aqueous KI)= 1.539 (2), D x= 1.541 (2) g cm -3, #(Cu Ka, 2 = 1.5418 A) = 40.58 cm -~, F(000) = 712, T= 293 K, R = 8.8% for 2054 significant refections. Red form (II): Mr= 350.09, triclinic, Pi, Z=2, a=9.796(2), b= 10.750 (2), c= 7.421 (1)A, a= 95.29 (2), fl= 0108-2701/84/111901-05501.50 70.18 (1), y = 92-.76 (2) °, V= 731.9 A 3, Din(flotation in KI) = 1.585 (3), D x = 1.588 (3) g cm -3, ~t(Cu Ka, 2 = 1.5418/~) = 40.58 cm -1, F(000) = 356, T=293 K, R = 5.8% for 1866 significant reflections. There are no unusual bond distances or angles. The triazole and two phenyl rings are planar. On the basis of packing considerations the possibility of intermolecular interactions playing a role in the reactivity of the starting material is ruled out.

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The morphologies and crystalline structures of melt-crystallized ultrathin isotactic poly(1-butene) films have been studied with transmission electron microscopy and electron diffraction. It is demonstrated that a bypass of form II crystallization can be achieved with an increase in its crystallization temperature. Electron microscopy observations show that melt-grown isotactic poly(1-butene) single crystals have a well-shaped hexagonal form, whereas form I crystals converted from form II display the morphologies of their tetragonal precursors. Electron diffraction results indicate that, instead of the twinned hexagonal pattern of the converted form I crystal, the directly formed form I single crystals exhibit an untwinned hexagonal pattern.

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The structures of single crystals of syndiotactic poly(butene-1) in form I, produced by thin-film growth, are studied by transmission electron microscopy and electron diffraction. Bright-field electron microscopy observation shows that the single crystal exhibits a regular rectangular shape with the long axis along its crystallographic b-axis. Electron diffraction results indicate an isochiral C-centered packing of a-fold helical chains in an orthorhombic unit cell corresponding to the C222(1) space group, according to the model proposed in the literature. The differences with the polymorphic behavior of syndiotactic polypropylene concerning the formation and the stability of the isochiral mode of packing are outlined.

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Chlortalidone (CTD) is an antihypertensive drug for which only two solid state phases have been structurally elucidated thus far. Here, we have prepared a chloroform solvate thereof, namely, CTD Form IV, and its structure was compared to those of Form I and Form III. Its two conformers exhibit a dual structural feature in relation to the antecedent polymorphs. Both CTD molecules of Form IV adopt a Form III-like conformation, which is featured, if the conformation of CTD Form I is used as a reference, by a rotation of about 90 degrees on the axis of the C-C bond bridging the substituted benzene and isoindolinyl rings. However, CTD Form IV assembles as in the Form I crystal packing despite the different stacking fashion of their centrosymmetric dimers. In contrast to Form I, there is no offset stacking in Form IV, which forces a bend of ca. 24 degrees between the planes passing through the isoindolinyl moieties of two [100]-stacked dimers. Chloroform molecules at a maximum stoichiometry of 0.25 mol per mol of the drug play a stabilizing role in the assembly of Form IV by filling the channels formed on the crystals.

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Advancing (θA) and receding (θR) contact angles were measured with several probe liquids on the external facets (201), (001), (011), and (110) of macroscopic form I paracetamol crystals as well as the cleaved (internal) facet (010). For the external crystal facets, dispersive surface energies γd calculated from the contact angles were found to be similar (34 ± 1 mJ/m2), while the polar components varied significantly. Cleaving the crystals exposed a more apolar (010) surface with very different surface properties, including γd = 45 ± 1 mJ/m2. The relative surface polarity (γp/γ) of the facets in decreasing order was (001) > (011) > (201) > (110) > (010), which agreed with the fraction of exposed polar hydroxyl groups as determined from C and O 1s X-ray photoelectron spectroscopy (XPS) spectra, and could be correlated with the number of non-hydrogen-bonded hydroxyl groups per unit area present for each crystal facet, based on the known crystal structures. In conclusion, all facets of form I paracetamol crystals examined exhibited anisotropic wetting behavior and surface energetics that correlated to the presence of surface hydroxyl groups.  © 2006 American Chemical Society.

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The study investigates the formal integration of English loanwords into the Swedish language system. The aim has been to analyse and describe the morphological/morphosyntactic and the orthographical integration of the loanwords. I have studied how the foreign language elements get accommodated to Swedish and which factors are relevant in the integration. The material for the study consists of Swedish newspapers published in Sweden and Finland in paper format (with a focus on the years 1975 and 2000) and newspapers in digital format on the net. The theoretical frame for the study is contact linguistics. The study is based on a sociolinguistic, structural and language political perspective on what language is, and what language contact is. The method used is usage-based linguistic analysis. In the morphological study of the loanwords, I have made both a quantitative and a qualitative study. I have analysed the extent to which loanwords show some indication of integration in Swedish, and to what extent they show no signs of integration at all. I have also analysed integration in relation to word classes i.e., how nouns, adjectives and verbs integrate and which factors are relevant for the result of the integration. The result shows that most loanwords (36 %) do not show any signs of being formally integrated in Swedish. They undergo neither inflectional, nor derivational changes. One fifth of the loanwords are inflected according to the rules of Swedish grammar. Nouns are generally more often than verbs placed in positions in the sentence where no formal adaption is needed. Almost all of the verbs in the material are inflected according to Swedish rules of grammar. Only 3 % of the loanwords are inflected according to English rules or are placed in an ungrammatical position in the sentence. The orthographical study shows that English loanwords very seldom get adapted to Swedish orthography. Some English vowel and consonant graphemes are replaced with Swedish ones, for example a, ay and ai are replaced with aj or ej (mail → mejl). The study also indicates that morphological integration is related to orthographical integration: loanwords that are inflected according to Swedish grammar are more likely to be orthographical integrated than loanwords that are inflected according to English grammar. The results also shows that the integration of loanwords are affected by mostly language structural factors and language political factors.

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The mutual influence of the components on the crystallization behaviour of polyblends, namely, isotactic polybutene-1 (PB) with low-density and high-density polyethylene (LDPE and HDPE), has been studied using techniques such as differential scanning calorimetry, infra-red spectroscopy, wide-angle X-ray diffraction, scanning electron microscopy, etc. Each component in the blend is observed to crystallize independently. There is phase separation and incompatibility, as shown from tensile properties and scanning electron microscopic observation of the fracture surface of the blend. For HDPE-PE blends (<30% HDPE), unusual form I′ crystals of PB are observed along with the usual form II.

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Structures and crystal form transition of the novel aryl ether ketone polymer containing meta-phenylene linkage: PEKEKK(T/I) were investigated by wide angle X-ray diffraction (WAXD), imaging plates (IPs) and small angle X-ray scattering (SAXS). The energy of activation of the decomposition reaction and degree of crystallinity of PEKEKK(T/I) were determined by WAXD and thermo-gravimetric analysis (TGA), respectively. Results obtained from WAXD and IPs show that crystal forms I and II coexist in the PEKEKK(T/I) samples isothermally cold crystallized in the temperature range from 180degreesC to 240degreesC and only form I occurs in PEKEKK(T/I) samples isothermally cold crystallized at 270degreesC. The radius of gyration (Rg), thickness of microregions with electron-density fluctuations (E) and distribution of particle sizes were investigated by SAXS.

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Epitaxial crystallization of syndiotactic polypropylene (sPP) on 2-quinoxalinol (2-Quin) yields, in the lower part of the crystallization range, the less common and metastable form II based on the packing of isochiral helices, rather than the stable antichiral form I. The contact plane is (110)(II). Form II exits only as a thin layer (< 50 nm) near the substrate surface. During further growth away from the surface, a transition takes place to the disordered form I, observed in "conventional" thin film growth. The epitaxial relationship rests only partly on dimensional matching with the chain axis repeat distance (which would be valid for both forms I and II) and on interchain distances. Whereas a better dimensional match would be achieved with form I, selection of the isochiral form II results from better correspondence of the surface topographies of the deposit (110)(II) sPP and substrate 2-Quin (001) contact faces.

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Cytenamide form I (R (3) over bar) undergoes a solid-state transformation upon heating to form II (P (1) over bar), with the structures exhibiting the same two-dimensional similarity that exists between the R (3) over bar and P (1) over bar forms of carbamazepine.

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Färg och form kan bidra till att skapa uppmärksamhet, förmedla budskap och skapa känslor som i sin tur kan öka sannolikheten av att kunden genomför köpet. Förpackningens färg och form bör synkronisera för att budskapen inte ska motsäga varandra, och det är mycket viktigt att designen lämpar sig till målgruppen. Färg kan ses som ett språk som kommunicerar med konsumenten, och att förstå detta språk kan vara ett starkt redskap inom marknadsföring och design. Det är vanligt att förpackningsdesign riktas mot något eller bägge könen och att ge produkten en karaktär av maskulint eller feminint kan vara ett effektivt tillvägagångssätt att särskilja produkten från resterande sortiment. I samband med färg och form är det nödvändigt att förstå konsumentens behov samt användning av produkten, och det är viktigt att skapa en god design riktad mot rätt målgrupp. Det är viktigt att förstå vad konsumenten attraheras till och vad som lockar till att genomföra ett köp. Syftet med denna studie var att ta reda på varför förpackningsdesign för duschcreme specificerade för kvinnor respektive män skiljer sig, och vad som anses vara kvinnligt och manligt när det kommer till färg och form, i samband med duschcremesförpackningar. För att ta reda på detta genomfördes en visuell innehållsanalys samt en enkätundersökning. Resultatet som genererades av dessa metoder sammanfattades i tabeller och diagram, som tydligt visar de färger som anses vara maskulina samt feminina. Mörka färger, som svart och blått, anses vara maskulina medan ljusa färger och rosa toner anses vara feminina. Mjuka grafiska element och former kopplas till femininitet medan motsatsen kopplas till maskulinitet. Slutsatsen av detta är att anledningen till att förpackningarna skiljer sig är för att lättare kommunicera med målgruppen, och i detta fall via färg och form.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The present study addresses the assembly in the chloroplast thylakoid membranes of PsaD, a peripheral membrane protein of the photosystem I complex. Located on the stromal side of the thylakoids, PsaD was found to assemble in vitro into the membranes in its precursor (pre-PsaD) and also in its mature (PsaD) form. Newly assembled unprocessed pre-PsaD was resistant to NaBr and alkaline wash. Yet it was sensitive to proteolytic digestion. In contradistinction, when the assembled precursor was processed, the resulting mature PsaD was resistant to proteases to the same extent as endogenous [correction of endogeneous] PsaD. The accumulation of protease-resistant PsaD in the thylakoids correlated with the increase of mature-PsaD in the membranes. This protection of mature PsaD from proteolysis could not be observed when PsaD was in a soluble form-i.e. not assembled within the thylakoids. The data suggest that pre-PsaD assembles to the membranes and only in a second step processing takes place. The observation that the assembly of pre-PsaD is affected by salts to a much lesser extent than that of mature-PsaD supports a two-step assembly of pre-PsaD.

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I den här avhandlingen är intresset riktat mot svensk utbildningspolitik och medborgarskap. I tider av globalisering, och med ett etablerat svenskt medlemskap i Europeiska unionen, har det nationella policyskapandet kring utbildningens medborgardanande funktion hamnat under ökat tryck. I studien undersöks hur detta hanteras i svensk utbildningspolitik under 1990-talet, en tid som utmärker sig genom betydande förändringar på utbildningsområdet i Sverige. Frågan är, mera precist, vilken riktning för skolans, enligt lag befästa, uppdrag att fostra demokratiska medborgare som utstakas i svensk utbildningspolitik vid denna tid. Genom att fästa vikt vid mål, visioner och motiv som formuleras i utbildningspolitiska 1990-talstexter klarläggs förståelser av medborgarskap som karaktäriserar svensk utbildningspolitik under denna tid. Även en bredare historisk analys görs, ur vilken historiska målsättningar med skolans medborgarfostran som föregår 1990-talets framträder. Studiens syfte är kritiskt. Förståelserna granskas utifrån vad de innesluter och vad de utesluter, vilka möjliga konsekvenser de kan tänkas få för olika individer och grupper i samhället, och om det finns öppningar för tänkbara alternativ. Studien visar på två historiska skiften vad gäller medborgarskapets innehåll och mening i det inhemska policyskapandet. Det första skiftet äger rum under 1990-talets tidiga del. Då bryts en etablerad samhällsbyggande medborgarroll upp, till förmån för andra mera marknadsorienterade medborgarroller. Under 1990-talets senare del, då marknadsorienteringen förstärks i neoliberal riktning, sker ett andra skifte; en historiskt vedertagen gemenskapstanke – nationen – bryts upp som grund för medborgerlig gemenskap. Denna tanke ersätts av en annan som är globaliseringsinriktad, vilken visar sig ha andra inne- och uteslutande mekanismer för olika individer och samhällsgrupper. Utifrån dessa forskningsrön tecknas avslutningsvis några konturer till ett alternativt sätt att tänka kring medborgarskap och gemenskap. Detta alternativ tar form i ambitionen att, i högre grad än vad som blir synligt i svensk utbildningspolitik, resonera kring möjligheter för ett medborgarskap bortom förhandstecknade indelningsgrunder för ett “vi”. Språk som politisk och samhällelig förändringskraft ges en central betydelse i avhandlingen. I analysen av texternas tal om skolans medborgarfostrande roll undersöks pågående politiska motsättningar när det gäller att vinna tal- och tolkningsföreträde till skolans fostransmål. Utgångarna av dessa motsättningar belyses genom tre områden för medborgarfostran som urskilts som centrala; ett politiskt, ett kulturellt samt ett ekonomi- och arbetslivsriktat. Genom dessa har rådande medborgarskapsdiskurser tagit form, ur vilka de utbildningspolitiska förståelserna av medborgarskap gestaltas och diskuteras.