Thesis--Columbia University. / Thesis statement mounted on t.p. Includes bibliographical references.

Thesis (Ph. D.)--Columbia University. / Published also without thesis note. Vita. "Finding list of government publications": p. [285]-329.

Thesis--Columbia University. / Thesis statement mounted on t.p. Includes bibliographical references.

Thesis (Ph. D.)--University of California, Los Angeles, 1986. / Includes bibliographical references.

Thesis (Ph. D.)--University of California, Los Angeles, 1986. / Includes bibliographical references.

Thesis (Ph. D.)--Boston College, 1992. / Includes bibliographical references (leaves 239-242).

Since the synthesis of Mn12, which can be regarded as the birth of the class of magnetic molecules, many different molecules of various sizes and structures have been produced. The magnetic nature of these molecules originates from a number of paramagnetic ions, whose unpaired electrons form collective angular momenta, referred to as spins. The interaction between these spins can often be described in the Heisenberg model. In this work, we use the rotational band model to predict the energy spectrum of the giant Keplerate {Mo72Fe30}. Based on the approximate energy spectrum, we simulate the cross-section for inelastic neutron scattering, and the results are compared to experimental data. The successful application of our approach substantiates the validity of the rotational band model. Furthermore, magnetic molecules can serve as an example for studying general questions of quantum mechanics. Since chemistry now allows the preparation of magnetic molecules with various spin quantum numbers, this class of materials can be utilized for studying the relations between classical and quantum regime. Due to the correspondence principle, a quantum spin system can be described exactly by classical physics for an infinitely large spin quantum number s. However, the question remains for which quantum numbers s a classical calculation yields a reasonable approximation. Our approach in this work is to develop a converging scheme that adds systematic quantum corrections to the classical density of states for Heisenberg spin systems. To this end, we establish a correspondence of the classical density of states and the quantum spectrum by means of spin-coherent states. The algorithm presented here allows the analysis of how the classical limit is approached, which gives general criteria for the similarity of the classical density of states to the quantum spectrum.

For the knowledge economy of the twenty-first century, intellectual skills (such as critical thinking) have been identified as imperative for success. Educational institutions have a responsibility to equip students with the knowledge and skills required for future employment. The South African Institute of Chartered Accountants has identified critical thinking as one of the skills that should be developed in Financial Accounting students who wish to become chartered accountants. For this limited-scope dissertation a qualitative study was done, applying a constructivist paradigm to a case study design, to explore the development of critical thinking in first-year Financial Accounting students in an open distance and e-learning context in South Africa. To achieve this, data were collected through semi-structured interviews with twelve academics and the use of document analysis. As the focus of the study was limited to two first-year financial accounting modules which form part of the South African Institute of Chartered Accountants accredited programme taught at an open distance and e-learning institution, the findings cannot be generalised. While the perceptions of students were not considered in the study, the findings provide valuable insight into the development of critical thinking in accounting modules. The findings revealed that, although academics believe critical thinking skills and good thinking habits should be developed in first-year Financial Accounting students, it is currently only done through a content-centred approach, or not at all. Furthermore, only technologies which academics are comfortable using, are being incorporated, mainly for the delivery of content. The recommendations made for curriculum evaluation and professional development relate specifically to these findings. / Vir die een-en-twintigste-eeuse kennisekonomie is intellektuele vaardighede (soos kritiese denke) geïdentifiseer as noodsaaklik vir sukses. Opvoedkundige instellings het 'n verantwoordelikheid om studente met die kennis en vaardighede toe te rus wat nodig is vir toekomstige indiensneming. Die Suid-Afrikaanse Instituut vir Geoktrooieerde Rekenmeesters het kritiese denke geïdentifiseer as 'n vaardigheid wat studente in Finansiële Rekeningkunde, wat geoktrooieerde rekenmeesters wil word, moet ontwikkel. Vir hierdie verhandeling van beperkte omvang, is 'n kwalitatiewe studie gedoen deur 'n konstruktivistiese paradigma toe te pas op 'n gevallestudie-ontwerp om die ontwikkeling van kritiese denke in eerstejaarstudente in Finansiële Rekeningkunde in 'n oop e-afstandsleerkonteks in Suid-Afrika te ondersoek. Om hierdie doel te bereik, is data versamel deur semi-gestruktureerde onderhoude te voer met twaalf akademici en dokumentontleding te gebruik. Omdat die studie beperk was tot twee eerstejaar finansiële rekeningkunde modules, wat deel vorm van die Suid-Afrikaanse Instituut vir Geoktrooieerde Rekenmeesters se geakkrediteerde program wat by 'n oop e-afstandsleerinstelling aangebied word, kan die bevindinge nie veralgemeen word nie. Alhoewel die studente se persepsies nie in die studie in ag geneem is nie, bied die bevindings waardevolle insig oor die ontwikkeling van kritiese denke in rekeningkundemodules. Die bevindings dui daarop dat, alhoewel akademici glo dat vaardighede in kritiese denke en goeie denkgewoontes in die eerste jaar van Finansiële Rekeningkunde onderrig moet word, word dit tans slegs deur 'n inhoudgebaseerde benadering gedoen, of glad nie. Verder word slegs tegnologieë geïnkorporeer waarmee akademici gemaklik is, hoofsaaklik vir die oordrag van die inhoud. Die aanbevelings vir kurrikulumevaluering en professionele ontwikkeling hou spesifiek verband met hierdie bevindings. / Kha ikonomi ya nḓivho ya ḓanwaha fumbili nthihi, zwikili zwa nḓivho (zwi ngaho vhukoni ha u humbula nga nḓila yo dzudzaneaho) zwo topolwa sa ndaela ya mvelaphanḓa. Zwiimiswa zwa pfunzo zwi na vhudifhinduleli u lugisela matshudeni nga ndivho na zwikili zwine zwa ṱodea mishumoni ya tshifhingani tshidaho. Tshiimiswa tsha Afrika Tshipembe tsha Vhomakone vha Akhaunthini tsho topola vhukoni ha u humbula nga ndila yo dzudzaneaho vhune ha tea u bveledzwa kha matshudeni a Akhaunthini ya Masheleni vhane vha tama u vha vhomakone vha muvhalelano. Ho itwa ngudo dza khwalithathivi dza desithesheni ya tshikoupu tsho pimiwaho, hu tshi khou u fhaṱwa ndivho na kupfesesele nga kha tshenzhemo kha u bveledza ngudo, u wanulusa vhukoni ha u humbula nga ndila yo dzudzaneaho kha nwaha wa u thoma kha matshudeni a Akhaunthuni ya Masheleni kha nyimele ya tshiimiswa tsha u guda u kule na kha lubuvhisia Afrika Tshipembe. U swikelela izwi, data yo kuvhanganyiwa nga kha inthaviwu dzo dzudzanywaho na vhoraakademi vha fumimbili na u shumisa musaukanyo wa linwalo. Sa musi ngudo yo vha yo sedza fhedzi kha mimodulu mivhili ya nwaha wa u thoma ya Akhaunthini ya masheleni ine ya vhumba tshipida tsha mbekanyamushumo ya akhiredithesheni ya Tshiimiswa tsha Afrika Tshipembe tsha Vhomakone vha Akhaunthuni ine ya funzwa kha tshiimiswa tsha u guda u kule na kha Lubuvhisia, mawanwa a nga si angaredzwa. Ngeno kuvhonele kwa matshudeni ku songo dzhielwa ntha kha ngudo, mawanwa o ṋetshedzwa ndivho ya ndeme kha mveledziso ya vhukoni ha u humbula nga ndila yo dzudzaneaho kha mimodulu ya akhaunthini. Mawanwa o dzumbulula uri, naho vhoraakademi vha tshi tenda uri zwikili zwa vhukoni ha u humbula nga ndila yo dzudzaneaho na maitele a kuhumbulele kwavhudi zwi fanela u bveledziswa kha nwaha wa u thoma wa matshudeni vha Akhaunthini ya Masheleni, zwa zwino zwi khou itwa fhedzi nga kha maitele o disendekaho nga zwi re ngomu, kana zwa sa itwe na luthihi. Zwi tshe zwo ralo, ndi thekhinolodzhi fhedzi dzine vhoraakademi vha takalela u dzi shumisa, zwo tanganyiswa, nga maanda ndisedzo ya zwi re ngomu. Themendelo dzo itwa kha u ela kharikhulamu na mveledziso dzi re na vhushaka na mawanwa anea o tiwaho. / Institute for Open and Distance Learning (IODL) / M. Ed. (Open and Distance Learning)