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  • 1.
    Alam, Rauful
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Mihai, Raducan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Eriksson, Lars
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för oorganisk kemi och strukturkemi.
    Szabo, Kalman J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Selective Formation of Adjacent Stereocenters by Allylboration of Ketones under Mild Neutral Conditions2013Ingår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 15, nr 10, s. 2546-2549Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Allylboronic acids readily react with a broad variety of ketones, affording homoallylic alcohols with adjacent quaternary and tertiary stereocenters. The reaction proceeds with very high anti stereoselectivity even if the substituents of the keto group have a similar size. a-Keto acids react with syn stereoselectivity probably due to the formation of acyl boronate intermediates. The allylation reactions proceed without added acids/bases under mild conditions. Because of this, many functionalities are tolerated even with in situ generated allylboronic acids.

  • 2.
    Alam, Rauful
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Pilarski, Lukasz T.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Pershagen, Elias
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Szabo, Kalman J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stereoselective intermolecular allylic C-H trifluoroacetoxylation of functionalized alkenes2012Ingår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 134, nr 21, s. 8778-8781Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Pd-catalyzed allylic C-H trifluoroacetoxylation of substituted alkenes was performed using PhI(OCOCF3)(2) as the oxidant and acyloxy source. Trifluoroacetoxylation of monosubstituted cyclopentenes and cyclohexenes proceeds with excellent regio- and diastereoselectivity. Studies with one of the possible (eta(3)-allyl)Pd(II) intermediates suggest that the reaction proceeds via stereoselective formation of Pd(IV) intermediates and subsequent stereo- and regioselective reductive elimination of the product.

  • 3.
    Szabo, Attila
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för matematikämnets och naturvetenskapsämnenas didaktik.
    Matematikundervisning för begåvade elever – en forskningsöversikt2017Ingår i: Nordisk matematikkdidaktikk, ISSN 1104-2176, Vol. 22, nr 1, s. 21-44Artikel, forskningsöversikt (Refereegranskat)
    Abstract [sv]

    Artikeln redovisar de huvudsakliga pedagogiska och organisatoriska metoder relaterade till begåvade elevers matematikundervisning som fokuseras i forskningslitteraturen – även könsskillnader, motivation och matematiskt begåvade elevers sociala situation i klassrummet diskuteras. Översikten visar att det finns åtgärder – t.ex. frivillig acceleration i ämnet där undervisningen är anpassad till elevens förkunskaper och kapacitet eller arbete med utmanande uppgifter i prestationshomogena grupper – som antas ha goda effekter på begåvade elevers kunskapsutveckling i matematik. Analysen visar också att det kan uppfattas som problematiskt att vara begåvad i matematik samt att begåvade flickor upplever vissa aspekter av matematikundervisningen annorlunda jämfört med motsvarande grupp pojkar.

  • 4.
    Szabo, Attila
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för matematikämnets och naturvetenskapsämnenas didaktik.
    Matematiska förmågors interaktion och det matematiska minnets roll vid lösning av matematiska problem2013Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [sv]

    Avhandlingen fokuserar matematiska förmågors interaktion och det matematiska minnets roll vid problemlösning. För att undersöka dessa företeelser, har jag analyserat matematiska förmågors uttryck hos högpresterande gymnasieelever. Eleverna löste nya och utmanande matematiska problem individuellt, under enskilda observationer. Studien visar att det matematiska minnet tar i anspråk en relativt liten andel tid av problemlösningsprocessen och är huvudsakligen närvarande i processens inledande fas. Trots att det matematiska minnet tar i anspråk en liten andel tid, så är det matematiska minnet avgörande för valet av problemlösningsmetoder eftersom eleverna väljer lösningsmetoder i processens inledande fas. Studien visar att valet av problemlösningsmetod har viktiga konsekvenser för elevers problemlösning. Om de valda metoderna inte leder till önskat resultat, så har eleverna mycket svårt för att ändra sina initialt valda lösningsmetoder. Studien visar också att elever som använder allmänna problemlösningsmetoder presterar bättre än elever som använder numeriska metoder.

  • 5.
    Szabo, Attila
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för matematikämnets och naturvetenskapsämnenas didaktik.
    Mathematical abilities and mathematical memory during problem solving and some aspects of mathematics education for gifted pupils2017Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis reports on two different investigations.

    The first is a systematic review of pedagogical and organizational practices associated with gifted pupils’ education in mathematics, and on the empirical basis for those practices. The review shows that certain practices – for example, enrichment programs and differentiated instructions in heterogeneous classrooms or acceleration programs and ability groupings outside those classrooms – may be beneficial for the development of gifted pupils. Also, motivational characteristics of and gender differences between mathematically gifted pupils are discussed. Around 60% of analysed papers report on empirical studies, while remaining articles are based on literature reviews, theoretical discourses and the authors’ personal experiences – acceleration programs and ability groupings are supported by more empirical data than practices aimed for the heterogeneous classroom. Further, the analyses indicate that successful acceleration programs and ability groupings should fulfil some important criteria; pupils’ participation should be voluntary, the teaching should be adapted to the capacity of participants, introduced tasks should be challenging, by offering more depth and less breadth within a certain topic, and teachers engaged in these practices should be prepared for the characteristics of gifted pupils.

    The second investigation reports on the interaction of mathematical abilities and the role of mathematical memory in the context of non-routine problems. In this respect, six Swedish high-achieving students from upper secondary school were observed individually on two occasions approximately one year apart. For these studies, an analytical framework, based on the mathematical ability defined by Krutetskii (1976), was developed. Concerning the interaction of mathematical abilities, it was found that every problem-solving activity started with an orientation phase, which was followed by a phase of processing mathematical information and every activity ended with a checking phase, when the correctness of obtained results was controlled. Further, mathematical memory was observed in close interaction with the ability to obtain and formalize mathematical information, for relatively small amounts of the total time dedicated to problem solving. Participants selected problem-solving methods at the orientation phase and found it difficult to abandon or modify those methods. In addition, when solving problems one year apart, even when not recalling the previously solved problem, participants approached both problems with methods that were identical at the individual level. The analyses show that participants who applied algebraic methods were more successful than participants who applied particular methods. Thus, by demonstrating that the success of participants’ problem-solving activities is dependent on applied methods, it is suggested that mathematical memory, despite its relatively modest presence, has a pivotal role in participants’ problem-solving activities. Finally, it is indicated that participants who applied particular methods were not able to generalize mathematical relations and operations – a mathematical ability considered an important prerequisite for the development of mathematical memory – at appropriate levels.

  • 6.
    Szabo, Attila
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för matematikämnets och naturvetenskapsämnenas didaktik.
    Mathematical memory revisited: mathematical problem solving by high achieving students2017Ingår i: Proceedings of the Tenth Congress of the European Society for Research in Mathematics Education (CERME10, February 1-5, 2017) / [ed] Thérèse Doole, Ghislaine Gueudet, Dublin: DCU Institute of Education, ERME , 2017, s. 1202-1209Konferensbidrag (Refereegranskat)
    Abstract [en]

    The present study deals with the role of the mathematical memory in problem solving. To examine that, two problem-solving activities of high achieving students from secondary school were observed one year apart - the proposed tasks were non-routine for the students, but could be solved with similar methods. The study shows that even if not recalling the previously solved task, the participants’ individual ways of approaching both tasks were identical. Moreover, the study displays that the participants used their mathematical memory mainly at the initial phase and during a small fragment of the problem-solving process, and indicates that students who apply algebraic methods are more successful than those who use numerical approaches.

  • 7.
    Szabo, Attila
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för matematikämnets och naturvetenskapsämnenas didaktik.
    Andrews, Paul
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för matematikämnets och naturvetenskapsämnenas didaktik.
    Examining the interaction of mathematical abilities and mathematical memory: A study of problem-solving activity of high-achieving Swedish upper secondary students2017Ingår i: The Mathematics Enthusiast, ISSN 1551-3440, Vol. 14, nr 1-3, s. 141-159Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper we investigate the abilities that six high-achieving Swedish upper secondary students demonstrate when solving challenging, non-routine mathematical problems. Data, which were derived from clinical interviews, were analysed against an adaptation of the framework developed by the Soviet psychologist Vadim Krutetskii (1976). Analyses showed that when solving problems students pass through three phases, here called orientation, processing and checking, during which students exhibited particular forms of ability. In particular, the mathematical memory was principally observed in the orientation phase, playing a crucial role in the ways in which students' selected their problem-solving methods; where these methods failed to lead to the desired outcome students were unable to modify them. Furthermore, the ability to generalise, a key component of Krutetskii's framework, was absent throughout students' attempts. These findings indicate a lack of flexibility likely to be a consequence of their experiences as learners of mathematics.

  • 8.
    Szabo, Attila
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för matematikämnets och naturvetenskapsämnenas didaktik. Stockholm City Education Department, Sweden.
    Andrews, Paul
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för matematikämnets och naturvetenskapsämnenas didaktik.
    Uncovering the Relationship Between Mathematical Ability and Problem Solving Performance of Swedish Upper Secondary School Students2018Ingår i: Scandinavian Journal of Educational Research, ISSN 0031-3831, E-ISSN 1470-1170, Vol. 62, nr 4, s. 555-569Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we examine the interactions of mathematical abilities when 6 high achieving Swedish upper-secondary students attempt unfamiliar non-routine mathematical problems. Analyses indicated a repeating cycle in which students typically exploited abilities relating to the ways they orientated themselves with respect to a problem, recalled mathematical facts, executed mathematical procedures, and regulated their activity. Also, while the nature of this cyclic sequence varied little across problems and students, the proportions of time afforded the different components varied across both, indicating that problem solving approaches are informed by previous experiences of the mathematics underlying the problem. Finally, students’ whose initial problem formulations were numerical typically failed to complete the problem, while those whose initial formulations were algebraic always succeeded.

  • 9.
    Szabo, Kalman J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Pincer complexes as catalysts in organic chemistry2013Ingår i: Organometallic pincer chemistry / [ed] VanKoten, G., Milstein, D., Berlin, Heidelberg: Springer Berlin/Heidelberg, 2013, s. 203-241Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Application of pincer complexes in catalytic applications is a rapidly expanding field in organic synthesis. This chapter is mainly focused on selective formation of carbon carbon, carbon nitrogen, and carbon metal (C B, C Si, and S-Sn) bonds, as well as transfer hydrogenation reactions. The described pincer-complex catalyzed processes are more efficient and more selective than the corresponding transformations catalyzed by metal salts and added ligands. Some of the described pincer-complex catalyzed reactions are not amenable by traditional metal catalysts at all. It has been demonstrated that the superiority of pincer-complex catalysts over the traditional ones is based on the high stability and well-defined structure and stoichiometry of these species. These properties of pincer complexes allow a rational design of active and highly selective catalysts.

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