1,720,994 research outputs found
Les catéchismes roumains du XVIe siècle
No full textRosetti A. Les catéchismes roumains du XVIe siècle. In: Romania, tome 48 n°191, 1922. pp. 321-334
Ov. Densuşianu, Vieaţa păstorească în poesia noastră populară, I ; Casa scoalelor, 1922
No full textRosetti A. Ov. Densuşianu, Vieaţa păstorească în poesia noastră populară, I ; Casa scoalelor, 1922. In: Romania, tome 49 n°194, 1923. pp. 283-285
Nicolae Drägan, Douä manuscripte vechi : codicele Tödorescu si codicele Martian, studiu si transcriere , 1914
No full textRosetti A. Nicolae Drägan, Douä manuscripte vechi : codicele Tödorescu si codicele Martian, studiu si transcriere , 1914. In: Romania, tome 47 n°185, 1921. pp. 123-129
Du nouveau sur la date des premières traductions roumaines de livres religieux
No full textRosetti A. Du nouveau sur la date des premières traductions roumaines de livres religieux. In: Romania, tome 80 n°317, 1959. pp. 79-82
Intake manifold primary trumpet tuning options for fuel flow limited high Performance I.C.E
No full textThe 2014 change in Formula One regulations, from naturally aspirated to highly-downsized and heavily-boosted hybridized power units, led to a relevant increase of the internal combustion engine brake specific power output in comparison with former V-8 units. The newly designed “downsized” engines are characterized by a fuel flow limitation and a relevant increase in the thermal loads acting on the engine components, in particular on those facing the combustion chamber. Furthermore, efficiency becomes an equivalent paradigm as performance. In the power unit layout, the air path is defined by the compressor, the intercooler and the piping from the intake plenum to the cylinder. Intake duct length is defined from intake plenum to valve seat and it is a key parameter for engine performance. In order to find the optimum length different design criteria can be applied: the so called “tuning”, the “un-tuning” or the “anti-tuning” are all valid possibilities, showing pros and cons. The scope of the paper is to study and present the possible different tuning options for the internal combustion engine (ICE) part of a hybrid F1 powertrain. From 2015, variable trumpet can be used: the continuous variable length may be used to optimize volumetric efficiency and furthermore to reduce knocking and improve combustion accordingly. The scope of the paper is to show and qualitatively compare all the different options for a hybrid powertrain with fuel flow limited combustion unit
Comparison of coated and immobilized chiral stationary phases based on amylose tris-[(S)-α-methylbenzylcarbamate] for the HPLC enantiomer separation of α-lipoic acid and its reduced form
Full text linkThe couple of chiral sulfur compounds α-lipoic acid (ALA)/α-dihydrolipoic acid (DHALA) has attracted considerable attention in recent years owing to its remarkable anti-inflammatory and antioxidant properties. It is well known that the chirality of the C6 plays a key role in determining the biological activity of ALA. The natural occurring (R)-ALA enantiomer is an essential cofactor for key oxidative metabolism enzyme complexes and, after oral administration of the racemic mixture, it shows higher plasma concentration than (S)-ALA. Differently, the in vivo enantioselective action difference between the enantiomers of DHALA has not yet been studied. This lacking is perhaps due to the unavailability of analytical methods capable of determining the enantiomeric composition of biological samples during pharmacokinetic and pharmacodynamic events. In the present work, the direct and baseline enantioresolution of both chiral acids by HPLC on two amylose-derived chiral stationary phases is presented. The proposed chiral enantioselective protocol, therefore, does not require pre- or on-column derivatization. The performance of the coated Chiralpak AS-H CSP and the new immobilized Chiralpak IH-3 CSP, which have the same chiral selector amylose tris-[(S)-α-methylbenzylcarbamate], were compared using conventional normal-phase mobile phases containing ethanol or 2-propanol as alcoholic solvents and a fixed percentage of trifluoroacetic acid. Nonconventional eluents containing dichloromethane, ethyl acetate, and 2-methyltetrahydrofuran as organic cosolvents were applied in the separation of the enantiomers of two carboxylic acids on the immobilized Chiralpak IH-3 CSP. The effect of the column temperature was carefully evaluated in order to improve enantioselectivity. Adequate amounts of enantiomers were isolated by an analytical-size Chiralpak IH-3 column and submitted to chiroptical measurements. The absolute configuration assignment of the isolated enantiomers was determined by a multidisciplinary procedure based on the comparison of the experimental and calculated chiroptical properties
Multimilligram-scale production implementation of atropisomers of 2,2′-bis(2,2′-bithiophene-5-yl)-3,3′-bithianaphthene
No full text2,2′-Bis[2-(5,2′-bithienyl)]-3,3′-bithianaphthene (1) is the progenitor of a class of C2 symmetric thiophene-based electroactive monomers that, when electrooxidized in the enantiomerically pure form, produce inherently chiral films endowed with outstanding electrochemical enantiorecognition properties. The enantioselective high-performance liquid chromatography (HPLC) is the only approach used so far to resolve the racemic form of 1 into enantiomers. In this work, an improved HPLC method for multimilligram enantiomer production is presented. Key factors controlling the enantioseparation, such as mobile phase composition and column temperature, were identified using a 100 × 4.6 mm i.d. Chiralpak IB-3 column and subsequently scaled up to a 250 × 10.0 mm i.d. Chiralpak IB column. In the optimized semipreparative conditions, about 34 mg of pure (P) and (M) enantiomers per hour could be produced
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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