bluuebunny/crossref_metadata_2025 huggingface dataset:
International relations in the Horn of Africa (1991–96)
Authors: Tekle Amare
Published: July 2007

The international relations of any region cannot be understood by reference to developments in that region alone, but must be viewed in the context of linkages between systems at various regions and levels. It is the combination of the dynamics within each system and its interaction with other systems — regional and global — that determine the pattern of inter‐state relations. The Horn of Africa is not an exception. Thus, both Markakis, who emphasizes the predominance of internal factors, and Lefebvre, who gives prominence to external factors, each make valid points about the situation in the Horn of Africa (Endnote 1). However, it would be risky to accept either point of view to the exclusion of the other. Another point needs to be made clear. All too often, it is assumed that the interests of foreign powers — especially the superpowers — have determined the course of history in a given region; this is not entirely true. In fact, if one is to judge by the pattern of conflicts and alliances in the Horn of Africa, it is the local dynamics that have had more influence on the actions of foreign powers rather than vice versa. This article will focus on the states of the Horn of Africa ‐ Eritrea, Ethiopia, Sudan, Somalia, Kenya, Djibouti, Uganda — and the linkages between this region and other regions as well as the global system.
Ethnicity and power in Ethiopia
Authors: Young John
Published: July 2007

Ethiopia is implementing a radical programme of decentralising state power to ethnic‐based regional units, which could be of interest to other countries in Africa faced with demands of ethnic communities for a greater role in the state. This apparent empowerment of ethnicity represents a complete reversal of this country's past practices, and is the joint product of the ethnocratic character of the state until recently and the policies adopted by the Tigray Peoples Liberation Front (TPLF) in its long struggle against the military regime that ruled Ethiopia during 1974–1991. This article examines the processes that brought forth this novel, and for Africa unprecedented, constitutional arrangement.
New development agendas: changes in UK NGO policies & procedures
Authors: Wallace Tina
Published: July 2007

This article reports on research carried out on changes in the operational management of a broad sample of British NGOs. Despite the diversity of NGOs it finds surprising convergence towards the application of certain managerial concepts and tools. Three of these ‐ Strategic Planning, Logical Framework Analysis and Evaluation are considered in detail and the questions of why they are being used and for what purpose posed. The evidence is overwhelmingly that they have been adopted to meet Northern needs ‐ to satisfy the demands of Northern funding institutions and to help NGO headquarters control growing organisations. Faced with this evidence the article looks critically at the claims that such NGO practice can be consistent with development theories which are based on greater empowerment of Southern ‘partners’ and is obliged to repeat arguments, previously thought to be widely accepted, that the use and understanding of such tools are culturally mediated and far from neutral.
Book notes
Authors: Love Roy , Bush Ray , Szeftel Morris
Published: July 2007

The Eritrean Struggle for Independence: Domination, resistance, nationalism 1941 ‐ 1993by Ruth Iyob; Cambridge: Cambridge University Press, 1995. xvi + 198.Reviewed by John Markakis

From Colonisation to Democracy: A New Historical Geography of South AfricabyAlan Lester (1996), London: I B Tauris.

The Political Economy of South Africa: From Minerals‐Energy Complex to Industrialisation
by Ben Fine and Zavareh Rustomjee (1996), London: Hurst & Co.

Changing the Rules: The Politics of Liberalisation and the Urban Informal Economy in Tanzania
by Alli Mari Tripp (1997), University of California Press.

The Poverty of Nations: The Aid Dilemma at the Heart of Africa
by James Morton (1996), London: I B Tauris.

Crisis Response: Humanitarian Band‐Aids in Sudan and Somalia
by John Prendergast (1997), London: Pluto Press.

Eritrea and Ethiopia: The Federal Experience
by Tekeste Negash (1997), Uppsala: Nordiska Afrikainstitutet.

The Lie of the Land: Challenging Received Wisdom on the African Environment
edited by Melissa Leach and Robin Mearns (1996), London: James Currey/Heine‐mann.

Political Economy and Identities in Kwazulu‐Natal: Historical and Social Perspectives
edited by Robert Morrell (1996), University of Natal: Indicator Press.
Losing Lomé: the potential impact of the commission guidelines on the ACP non‐least developed countries
Authors: Watts Patrick
Published: July 2007

Relations between European Union (EU) states and associated underdeveloped economies (the ACP states) have been largely governed by the Lomé Conventions. Likely difficulties in gaining World Trade Organisation (WTO) approval for a renewal of Lomé IV in its current form, and recognition that Lomé has been an insufficient support to the ACP group, has led the European Commission to search for an alternative framework. Its proposed new guidelines bring the debate forward on what a politically and legally feasible, and economically mutually beneficial framework might involve. They include a proposal that aid be focused on countries with a proven commitment to poverty eradication and conflict prevention, and offer Lomé‐style access to non‐ACP Least Developed Countries (LLDCs).

Yet they fail to respond to ACP trade interests, and sit uneasily with the stated development aims of previous Lomé conventions. ACP non‐LLDC's will have to chose between negotiating ill‐defined Free Trade Agreements (FTA), or acceeding to the Generalised System of Preferences (GSP), markedly reducing access to EU markets. The costs ‐ in foreign exchange foregone and livelihoods destroyed ‐ could be considerable, as is shown by case studies of Zimbabwe, Ghana, and the Windward Islands.

Summary recommendations are made, finally, as to how EU trade preferences for ACP countries might best meet the needs of the majority, including a ten year waiver, allowing scope to adjust to new competitive pressures and to begin diversification of export bases; and simplified access to EU markets for the LLDC's.
Journalism & armed conflict in Africa: the civil war in Sierra Leone
Authors: Khan Amadu
                      Wurie
Published: July 2007

Unusually for discussions of the press in West Africa, this article is written by a journalist‐academic, who for a large part of 1990s worked for the Sierra Leonenan human rights newspaper For Di People,reporting on and analysing the civil war in Sierra Leone. Drawing on his experience, he sets out in detail the nature of accusations of bias against the local and foreign media in Sierra Leone, accusations made not only by interested parties, but also by a wide range of readers or listeners, and which have been seen as materially affecting the course of the war and attempts at mediation and peace‐making. A variety of reasons for vulnerability to such accusations are then examined, including the exigencies of war reporting, journalistic practice in Sierra Leone, the political economy of the press, and the problems created both by harsh government restrictions on press freedom and the media's response to them. The article argues that while there are instances of overt and calculated bias in reporting of the civil war, it is very difficult to draw a clear distinction between ‘intended’ and ‘unintended’ bias.
Visual "Drive" and Cinematic Narrative: Reading Gaze Theory in Lacan, Hitchcock, and Mulvey
Authors: Manlove Clifford T
Published: July 2007

This essay reconsiders the psychoanalytic theory derived from Sigmund Freud and Jacques Lacan that Laura Mulvey uses to support her theory of the gaze in the 1975 essay "Visual Pleasure and Narrative Cinema." "Visual 'Drive' and Cinematic Narrative" also reconsiders and rereads the three Alfred Hitchcock films Mulvey uses to prove her theory of the patriarchal gaze: Vertigo, Rear Window, and Marnie.
Association between T102C and A–1438G polymorphisms in the serotonin receptor 2A (5-HT2A) gene and schizophrenia: relevance for treatment with antipsychotic drugs
Authors: Peñas-Lledó Eva M. , Dorado Pedro , Cáceres Macarena C. , de la Rubia Alfredo , LLerena Adrián
Published: July 2007

Clin Chem Lab Med 2007;45:835–8.
Spectroscopic studies of poly(vinyl alcohol) films filled with a lanthanum/N‐ethylmorpholine complex
Authors: El‐Kader Kamal M. Abd , Anwar Zeinab
Published: July 2007

Poly(vinyl alcohol) (PVA) films with different concentrations of lanthanum ions were prepared with a casting technique. The thickness of the prepared samples was 0.25 mm. Optical absorption and transmission measurements were performed for thesesamples. The ultraviolet–visible absorption spectra of pure PVA showed absorption bands at 200, 275, and 325 nm, which were assigned to the presence of carbonyl groups. The absorption spectra of doped PVA films showed an observable change in the band position with the filling levels. This was due to the link between the lanthanum metal ion and the polymer OH groups. The dependence of the absorption coefficient on the photon energy was determined, and the band tails and energy gaps were calculated. The band tail increased, whereas the optical gaps decreased, as the concentration of lanthanum ions increased. X‐ray diffraction was used to characterize the prepared films. The results indicated the appearance of several new bands not existing for the lanthanum ions or PVA. Direct current/voltage characterization curves were measured for PVA–lanthanum films with different concentrations, and they showed remarkable increases in the conduction current of about 3 orders of magnitude in comparison with that of the pure PVA film. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Akustisch‐thermische Analyse von Korund‐Einkristallen
Authors: Kvapil J. , Kment V.
Published: July 2007

Eine zur akustisch‐thermischen Analyse (ATA) von Korund‐Einkristallen entwickelte Apparatur wird kurz beschrieben, und ihre Anwendung zur Beurteilung der Wirksamkeit des Temperungsprozesses wird besprochen. Die Apparatur ermöglicht Schallanalysen im Temperaturgebiet bis etwa 1600 °C.

Die mit dieser Methode an synthetischen Korundbirnen gemessene Erniedrigung der inneren Spannung stimmt mit den Ergebnissen der optischen Spannungsmessung quantitativ überein. Die ATA von synthetischen Rubinen hat gezeigt, daß für die Temperung auch das Temperaturgebiet um etwa 350 °C, in dem eine Änderung der Gitterkonstante eintritt, von Bedeutung ist.
Eine Vakuum‐Spaltapparatur für Epitaxieuntersuchungen an Alkalihalogeniden
Authors: Schoenborn W. , Wäsch R.
Published: July 2007

Definierte Untersuchungen zur Epitaxie erfordern adsorptionsfreie Substratoberflächen. Entsprechende Oberflächen lassen sich durch Spaltung im Vakuum erzeugen.

Die hier beschriebene Apparatur erlaubt die gleichzeitige Spaltung von 6 Alkalihalogeniden im Dampfstrahl. Die Spaltung erfolgt durch Zerbrechen der Kristalle. Zwei elektronenmikroskopische Aufnahmen der Abscheidung von PbS auf NaF und NaJ geben über die Güte der Spaltflächen Auskunft.
Bestimmung von kristallographischen Elementen stabförmiger kubischer Einkristalle (III)
Authors: Bohm J. , Wadewitz H.
Published: July 2007

Es werden einige Verfahren und Methoden zur Bestimmung von kristallographischen Elementen stabförmiger kubischer Einkristalle im Zusammenhang dargestellt. Speziell berücksichtigt werden Fragen der kristallographischen Orientierung und Gleitvorgänge. Die Beschreibungen sind so ausführlich, daß sie als Anleitung für entsprechende praktische Aufgaben dienen können. Im dritten Teil werden rechnerische Verfahren unter Bezug auf Vektoren angegeben.
Hochvakuumaufdampfung von Germanium auf NaF und NaCl
Authors: Mietz I.
Published: July 2007

Bei einem Vakuum von 10−5 Torr wurde Germanium auf luftgespaltene und vakuumgespaltene NaCl‐ und NaF‐Substrate aufgedampft. In Abhängigkeit von der Substrattemperatur (280–500°C), der Aufdampfgeschwindigkeit (1–35 Å s−1) und der aufgedampften Schichtdicke (100–1500 Å) wurde die Struktur der Germaniumabscheidungen untersucht. Hierbei interessierten der Übergang amorph/kristallin, die Zahl und Größe der Kristallite, ihre Orientierung und Anordnung auf der Substratoberfläche sowie der prozentuale Anteil der mit Germaniumkristalliten bedeckten Substratoberfläche. Die Untersuchungen erfolgten mit einem Elektronenmikroskop durch Abbildung und Beugung.
Polymorphism, optical and photoelectrical properties of lead monoxide thin single crystals
Authors: Bordovskij G. A. , Izvozčikov V. A.
Published: July 2007

The optical and photoelectric properties of the hybridal polymorphic lead monoxide single crystals have been studied. The crystals core is of orthorhombic structure, and tetragonal monoxide is present in the surface layer. The spontaneous and artificial enantiotrophical transformation of orthorhombic to hybridal single crystals results in: 1) appearing of additional absorption band; 2) activation of photoelectric sensity \documentclass{article}\pagestyle{empty}\begin{document}$ \left({\frac{{\Delta I}}{{I_D }} \approx 10^5 {\raise0.7ex\hbox{${\rm o}$} \!\mathord{\left/ {\vphantom {{\rm o} {\rm o}}}\right.\kern-\nulldelimiterspace} \!\lower0.7ex\hbox{${\rm o}$}}} \right) $\end{document}; 3) the spectral response shows the form characteristic for the case of high surface recombination velocity with maximum photocurrent about ∼615 nm. The activation of the photoelectric sensity is explained by the formation of the tetragonal (red) monoxide.
Über die Komplexbildung zwischen Zink ‐ und Blei(II)‐thiocyanat
Authors: Dost J. , Steinike U. , Paudert R.
Published: July 2007

Zink‐ und Blei(II)‐thiocyanat reagieren bei der Trockenmahlung oder beim Schütteln von Bleithiocyanat in gesättigter Zinkthiocyanatlösung zu einer intensiv gelben Verbindung der stöchiometrischen Zusammensetzung ZnPb(SCN)4. Es werden die Ergebnisse vo Remissionsmessungen, IR‐spektroskopischen und rötgenographischen Untersuchungen beschrieben.
Texturanalyse metallischer Werkstoffe und ihre Bedeutung für die laufende Produktionskontrolle
Authors: Lihl F.
Published: July 2007

Es werden die verschiedenen Arten von Texturen diskutiert. Dies sind neben den Wachstumstexturen vor allem die Umformungs‐ und Rekristallisationstexturen. Sie hängen von einer großen Anzahl von Parametern ab, z. B. Kristallstruktur, Legierungszusammensetzung, Walzgrad, Walztemperatur, Glühtemperatur, Glühdauer. Die als Ideallagen auftretenden Orientierungen werden durch Orientierungsmatrizen dargestellt. Der Zusammenhang zwischen den Ideallagen der Verformungstextur und denen der Rekristallisationstextur kann durch eine Umkristallisationsmatrix beschrieben werden. Hierfür werden einige Beispiele angegeben. Der Zusammenhang zwischen der Textur und den Eigenschaften technischer Materialien wird diskutiert. Daraus ergibt sich die Notwendigkeit der Texturkontrolle bei Produktionsprozessen. Es wird eine einfaches, diesem Zweck dienendes Gerät beschrieben.
Umrechnung der Winkel‐Orientierungsdaten einer Einkristall‐Oberfläche beim Wechsel des Bezugs‐Koordinatensystems des Einkristallgitters im kubischen System
Authors: Schmidt G. K.
Published: July 2007

In der vorliegenden Arbeit werden die Zahlenwerte von über 100 Umrechnungsmatrizen angegeben, mit denen man die auf niedrig indizierte kristallografische Dreibeine bezogenen Winkelorientierungsdaten einer Einkristalloberflächen‐Normalen für ein kubisches ([100] – [110] – [111]) Bezugssystem umrechnen kann. Wie unter Verwendung der Umrechnungsmatrizen ein präzises Verfahren für die Orientierungsbestimmung von Einkristalloberflächen‐Normalen arbeitet, wird beschrieben.
Mechanismus der nichtstationären Keimbildung und des Kristallwachstums in einem Modellglase
Authors: Gutzow I. , Toschev S. , Marinov M. , Popov E.
Published: July 2007

Es wird die Keimbildung und das Kristallwachstum in glasbildenden Schmelzen am Beispiel eines Modells, des sog. Graham'schen Glases (NaPO3)x untersucht. Die Keimbildung erwies sich als ein nichtstationärer Prozeß; eine konsequente Anwendung der Theorie erlaubt auch in diesem Falle, die für die Kristallisation wichtigsten Daten der homogen und heterogen geführten Kristallisation zu bestimmen. Es wird eingehend die nichtstationäre Keimbildung isotroper und kristalliner Keime diskutiert und mit dem Experiment verglichen. Es wird auch der Versuch gemacht, über den Mechanismus der linearen Kristallisationsgeschwindigkeit zu entscheiden. Auf Grund elektronenmikroskopischer Daten und des Temperaturverlaufes der Viskosität wird die Vermutung geäußert, daß das Wachstum durch zweidimensionale Keimbildung bestimmt wird.
Über die Ausbildung der Ausscheidungsstrukturen von Kupfer in Silizium in Abhängigkeit von einigen Dekorationsparametern
Authors: Fricke P.
Published: July 2007

In Siliziumeinkristallen wurde das Ausscheidungsverhalten von Kupfer in Abhängigkeit von der Dekorationstemperatur, der Dekorationszeit und der Abkühlrate untersucht. Die Dekoration erfolgte in einem Silitstabofen in Luft bei 700–1200°C innerhalb einer Minute bis 8 Stunden bei Abkühlraten von 0,5 grd s−1 bis 20 grd s−1. Die erhaltenen Ausscheidungen wurden mit einem IR‐Fernsehmikroskop beobachtet.
Die Methode der Texturuntersuchung mittels Neutronenbeugung und ihre besonderen Anwendungsvorteile
Authors: Kleinstück K. , Tobisch J.
Published: July 2007

Ausgehend von den physikalisch bedingten Mängeln, die den Anwendungsbereich der röntgenographischen Texturuntersuchung beschränken, werden die spezifischen Vorteile der Neutronenbeugungsmethode dargelegt. Diese sind gegeben durch die geringe Absorption der Neutronen in den meisten Werkstoffen. Einige neutronographische Untersuchungsbeispiele sollen die diskutierten Vorteile belegen, insbesondere den Aussagegehalt und die hohe Genauigkeit quantitativ ermittelter vollständiger Polfiguren.
Further data on the preparation of extremely pure sodium chloride crystals
Authors: Raksányi K. , Voszka R.
Published: July 2007

The following methods for purification of sodium chloride were compared in relation to their effectiveness: ion exchange, extraction, crystallization from solution, precipitation and distillation. For the purification of sodium chloride the ion exchange followed by a crystallization from solution in a teflon vessel appeared to be the most effective method giving a sodium chloride with an alkaline earth content about 1 × 10−7mole/mole.
Some remarks on the statistical character of crystal growth
Authors: Malicsko L.
Published: July 2007

The instantaneous growth rate of KBr crystals growing under constant external conditions in a supersaturated aqueous solution and that of fixing salt crystals growing in an under‐cooled melt show statistical fluctuations. According to our experiments the instantaneous growth rate – as a probability variable – may be described with a good approximation by using a Maxwellian probability density function.
Der Einfluß der Kristallisationswärme auf die Verschiebungsgeschwindigkeit der Kristallisationsfront in Schmelzen
Authors: Todes O. M.
Published: July 2007

[Russian text ignored].
Evaporation of Zinc Single Crystals
Authors: Iwanov D. , Nanev Chr. , Kaischew R.
Published: July 2007

The dislocation nature of defects leading to local evaporation of the {0001} face of zinc single crystals is proved. Two kinds of pits appear on the emergence points of dislocations, upon heating the crystals in vacuum, that is, hexagonal ones on screw dislocations and conical ones on edge dislocations (and probably on impurities). Hexagonal pits appeared at the growth points of whiskers upon evaporation. This is in excellent agreement with the assumption that whiskers grow by a screw dislocation mechanism.

Deepening and broadening of the pits were studied by interferometry. It was found that the change in profile with time can be described by the equations of Frank's kinematic theory. The same theory was used to calculate the step flux along the basal face of zinc single crystals upon evaporation at 250, 270, and 290°C. The rate of advance of unit steps was determined from the flux and compared with the theoretically expected one. The temperature dependence of this rate made it possible to estimate the vibrational frequency of the atoms in the crystal lattice as well as the evaporation heat of zinc. The reasonable values obtained demonstrate the correctness of the interpretation of the experimental data.
Beiträge zum Ätzen von Galliumarsenid (II) Zur Kinetik der Auflösung von GaAs
Authors: Voigt R. , Neels H.
Published: July 2007

Untersucht wird die Kinetik der Auflösung von {111}‐ und {100}‐Ebenen von GaAs in NaClO‐ und HNO3‐Lösungen sowie im HF/CrO3‐Lösungssystem. Dazu werden Auflösungsgeschwindigkeiten bestimmt und mit Hilfe der Arrhenius‐Gleichung w = C · e Aktivierungsenergien und Geschwindigkeitskonstanten angenähert ermittelt. Es ergeben sich Anhaltspunkte für den geschwindigkeitsbestimmenden Schritt (Diffusion ‐ Konvektion, heterogene chemische Reaktion). Bei der Auflösung von GaAs können je nach Art des Mediums (Konzentrationen) Diffusion oder chemische Reaktion geschwindigkeitsbestimmend sein. In manchen Fällen läßt sich aus der Größe der Geschwindigkeitskonstanten das Erscheinen oder Nichterscheinen von Ätzgruben verstehen. Die Auflösungsgeschwindigkeit w für sich allein gestattet keine zuverlässige Aussage über die Wahrscheinlichkeit der Bildung von Ätzgruben.
The Influence of AsCl3 Impurity on Growth Mechanism and Structure Perfection of Autoepitaxial Germanium Films
Authors: Stepanova A. N. , Sheftal N. N.
Published: July 2007

The changes of film morphology and microtwin concentration in these films caused by AsCl3 impurity have been studied. The correlation of growth mechanism and structure perfection of the films has been revealed.
Phasen und Epitaxien in gasnitrierten polykristallinen Fe‐Blechen und einkristallinen Fe‐Folien
Authors: Amthauer G. , Gebhardt M. , Neuhaus A.
Published: July 2007

Es wurden die Phasen‐ und Epitaxiebeziehungen nitrierter Eisenbleche und ‐Folien mittels Röntgen‐ und Elektronenbeugungsmethoden untersucht. Dabei wurden die folgenden, in zeitlicher Bildungsfolge aufgeführten Nitrierphasen gefunden: α Fe(N) (als feste Lösung) ‐ Fe4N (γ′‐Phase) ‐ ϵ‐Phasen (mit ϵ‐Fe3N und ϵ‐Fe2N) ‐m ζ‐Fe2N.

Alle genannten Nitrierphasen gehen, laufende N‐Zufuhr vorausgesetzt. durch epitaxisch initiierte Gitterumbaureaktionen auseinander hervor (= Topotaxie).

Es konnten epitaxische Verwachsungen aller in der obigen Bildungsfolge benachbarten Fe‐Nitride miteinander und über Epitaxiekette auch mit αFe nachgewiesen werden und zwar: αFe mit Fe4N(γ′); Fe4N(γ′); mit ϵ‐Fe3N; ϵ‐Fe3N mit ϵ‐Fe2N und ϵ‐Fe2N mit ζ‐Fe2N. Alle zugehörigen Verwachsungsgesetze konnten festgelegt werden. Von besonderer Aussagekraft erwiesen sich hierbei nitrierte Fe‐Einkristallfolien von ≈600 Å Dicke, die durch Vakuumaufdampfung auf (001)‐NaCl bei 475°C gezüchtet worden waren.
Short range order parameters for ternary zincblende substitutional solid solutions
Authors: Brühl H. G. , Schmidt W.
Published: July 2007

The determination of Warren's short range order parameters (pair correlations) for substitutional A1‐xBxC‐type solid solutions by means of diffuse X‐ray scattering is described. The relations obtained are applied to the diffuse X‐ray scattering of Ga0.16Al0.84As solid solutions being under different thermal treatment.
Ergebnisse bei der Darstellung von GaAs‐Einkristallen
Authors: Schulz M. , Schaefer H. , Seifert M. , Heckert H.
Published: July 2007

Es wird über Arbeiten zur Züchtung von 〈111〉 und 〈100〉 orientierten GaAs‐Einkristallen nach der Czochralski‐Technik mit Abdeckschmelze berichtet. Dargestellt werden Versuchsergebnisse zur Kristallperfektion und zur Dotierung. Für Zinn‐und Tellur‐dotierte GaAs‐Einkristalle werden Zusammenhänge zwischen eingesetztem Dotierungsmaterial und den Kristalleigenschaften experimentell untersucht und diskutiert. Der bei den Untersuchungen ermittelte Verteilungskoeffizient für Sn in GaAs wird mit früher veröffentlichten Werten verglichen. Des weiteren werden Ergebnisse über die Homogenität hinsichtlich der Dotierung und der Perfektion dargestellt.
Colour centre formation in corundum doped with divalent ions
Authors: Kvapil Jiři , Perner B. , Súlovský J. , Kvapil Jos.
Published: July 2007

The colour changes of corundum crystals annealed in hydrogen, oxygen and argon, and exposed to an UV irradiation is described. The comparison of samples doped with Be, Mg, or Fe is given. The change from pink colour to brown of rubies as well as the yellow colour of sapphires is attributed to the O− centre formation which causes an increase of the absorption between 400 to 480 nm.
Study on a simple model of recrystallization of large crystals
Authors: Skřivánek J. , Žáček S. , Vacek V.
Published: July 2007

In this paper a simple model of recrystallization is presented for crystallization of larger crystals than such ones, for which the explanation of Ostwald ripening can hold. Equations describing the particle size distribution are formulated and solved for a special case. The results obtained are in a qualitative agreement with so far observed facts.
Röntgenographische Bestimmung von Gitterdefekten in Magnetiten
Authors: Nestler C.‐G. , Kämpfe B. , Faust A. , Lange D.
Published: July 2007

Von unterschiedlichen Magnetiten wurde das Verhältnis Fe2+:Fe3+ chemisch bestimmt und Röntgenbeugungsuntersuchungen wurden durchgeführt. – Die Ergebnisse zeigen, daß alle untersuchten Magnetite in Wirklichkeit Mischkristalle des Systems Magnetit: Maghaemit sind. Mit steigendem Fe3+‐Anteil wurden lokale Inhomogenitäten des Fe2+:Fe3+‐Verhältnisses festgestellt.
Lang method applied to investigation of Al single crystal initial structure and of its effect on the eventual development of plastic strain
Authors: Novikova I. G. , Pustovalov V. V. , Startsev V. I.
Published: July 2007

The land method was used to study the structure of Al single crystals (99.9997% pure) grown from the melt, the thermal stability and the character of changes in different subgrain structures during work hardening. The method has proved to permit observation of slip development both in the early strain region (where occurs “levelling” of the structure of the bulk under strain), and during concert dislocation movement in specific slip planes up to large strains at 4.2°K.
Surface and contact properties of GaN produced from GaAs
Authors: Nieke H. , Rennert K. J. , Thoma A.
Published: July 2007

Samples of some thickness and extent showed fine cracks on the brink already after oxidization in Ga2O3 which became more distinctive after nitriding into GaN. Current‐voltage characteristics were recorded from different long nitrided samples with contacts of In, Sn, Sb, and Te. The long nitrided samples had a lower resistance. Some of the samples showed hysteresis effects with characteristics similar to varistors.
Zum Zusammenhang von Verfärbungserscheinungen und Gitterdeformationen in synthetischen Quarzeinkristallen
Authors: Härtwig J. , Dietz R.
Published: July 2007

Synthetische Quarzeinkristalle mit Rauchverfärbungsstreifen senkrecht zur Wachstumsrichtung zeigen Maxima der reflektierten Röntgenstrahlung (Reflex (0003)) an Stellen, an denen sich die Absorption im optischen Bereich stark ändert. Nachweisbare Komponenten des Verschiebungsvektors liegen parallel zur Wachstumsrichtung. In Bereichen mit starker Verfärbung ist das Gitter gedehnt.
Investigation of a new LPE method of obtaining AlGaAs heterostructures
Authors: Alferov Zh. I. , Andryev V. M. , Konnikov S. G. , Larionov V. R. , Pushny B. V.
Published: July 2007

A more detailed description of some peculiarities of the LPE method published by ALFEROV et al. (1974, 1975) for obtaining multilayer AIIIBV heterostructures and more precise details of the boat construction are given. A particular attention is paid to intermediate transient layers.
Zur Gleichgewichts‐ und Wachstumsform von β‐Kupferphthalocyanin‐Einkristallen
Authors: Kersten F. , Hamann C.
Published: July 2007

Mit der Methode der PBC‐Vektoren von HARTMAN und PERDOK wird die Gleichgewichtsform von β‐Kupferphthalocyanin‐Einkristallen bestimmt und mit der experimentell ermittelten Wachstumsform aus der Gasphase gezüchteter Kristalle verglichen. Es zeigt sich prinzipielle Übereinstimmung. Die Kristalle sind von nadelförmigem Habitus, die Tracht wird durch die Formen {001}, {201}, {100}, {101} und {110} gebildet. Das Längen–Breiten‐Verhältnis der Kristalle läßt sich durch die Variierung des Inertgasdruckes beeinflussen. Diese Abhängigkeit wird auf die Diffusion des Nährstoffdampfes zurückgeführt.
Zur Röntgenbeugung an kleinen kohärenten Kristallbereichen
Authors: Berger H.
Published: July 2007

Für kohärente Einkristalle mit sehr geringen Abmessungen werden Beziehungen für die Winkelintervalle der einfallenden und reflektierten Röntgenstrahlen im Beugungsfall abgeleitet. Im Fall einer dünnen Schicht ergeben sich nach der kinematischen Beugungstheorie explizite Ausdrücke, die sich auch als Grenzfall aus den Beziehungen der dynamischen Theorie herleiten lassen. Das Verhalten der Strahlen ist dabei völlig analog zum Beugungsgeschehen an großen perfekten Einkristallen. Für einen isometrischen kleinen Kristall sind die quantitativen Zusammenhänge von der konkreten experimentellen Anordnung abhängig. Die grundsätzlichen diffraktometrischen Meßmöglichkeiten für diese Winkelintervalle der Beugung werden betrachtet und hinsichtlich ihres Informationsgehaltes verglichen. Für einige praktisch wichtige Anwendungsbeispiele diffraktometrischer Untersuchungen werden die Konsequenzen diskutiert, die sich bei Berücksichtigung der Kohärenzlängenbeiträge ergeben. Dabei wird speziell die Möglichkeit abgeschätzt, einen solchen Beitrag durch Registrierung der Rockingkurve bei festem Winkel 2⊖ experimentell zu ermitteln.
Effect of CuCl2 · 2 H2O additive in ethanol on dissolution and selective etching behaviour of CsI crystals
Authors: Sangwal K. , Urusovskaya A. A. , Smirnov A. E.
Published: July 2007

{100} faces of Kyropoulos grown CsI crystals had undergone a selective etching, and CsI spheres of ∼ 10 mm in diameter were subjected to dissolution at room temperature for 10 hrs. The results are: pure ethanol does not bring about any anisotropy in dissolution, addition of CuCl2 · 2 H2O leads to an anisotropy in dissolution of CsI, change in CuCl2 · 2 H2O concentration changes etch pit morphology, whereas the dissolution form does not depend on additive concentration. With increasing CuCl2 · 2 H2O etching rates at first increase, later decrease, dissolution rates linearly increase.
Zur Bestimmung der Kristallitgrößenverteilung von Metallen auf Katalysatorträgern aus Röntgenweitwinkelmessungen (I). Ermittlung primärer Verteilungskenngrößen aus Linienprofilen
Authors: Spindler Herbert , Orban Peter , Westphal Bodo
Published: July 2007

Es werden die Möglichkeiten zur Bestimmung der Größenverteilungen von Metallkristalliten in Trägerkatalysatoren aus den Profilen von Röntgenweitwinkelinterferenzen untersucht. Dabei erweist sich ein Fourier‐Verfahren als zweckmäßig, das primär die Momente der Sehnenlängenverteilung liefert. Aus den Ergebnissen lassen sich für die Metallkristallite Verteilungsfunktionen ableiten, die mit hoher Genauigkeit die experimentellen Linienprofile wiedergeben.
Correlation between preparation variables and dielectric data of GaN formed by GaAs conversion
Authors: Procházková Olga , Šrobár F.
Published: July 2007

Polycrystalline GaN samples were prepared by two‐stage conversion of monocrystalline GaAs. Dependence of material properties on temperature and duration of the nitriding treatment was studied mainly by means of dielectric data taken in the range 0.25… 110MHz. Existence of optimum nitriding temperature, reported by previous workers, was borne out, and an attempt was made at its explanation in the framework of a simple model.
Zur Korrespondenz von Kristallstruktur und Habitus. Bestimmung der Molekülschwerpunkte in organischen Kristallen
Authors: Follner H.
Published: July 2007

Schraubenachsen und Gleitspiegelebenen vermindern die morphologische Bedeutung bestimmter Kristallflächen. Es wird gezeigt, daß auch Pseudosymmetrien die Kristalltracht beeinflussen. Bei organischen Kristallen ist es in günstigen Fällen möglich, mit Hilfe „morphologischer Auslöschungstabellen”︁ näherungsweise die Molekülzentren zu bestimmen.
Röntgenografische Untersuchung des Debye‐Waller‐Faktors und der Gitterkonstanten von V3Si‐Pulver im Temperaturbereich von 25 K bis 1000K
Authors: Försterling G. , Hegenbarth E.
Published: July 2007

Im Temperaturbereich von 25 K bis 1000 K werden die Temperaturabhängigkeit der integralen Intensität und Braggwinkel der elastisch gestreuten Röntgenstrahlung von V3Si‐Pulver ermittelt. Die gemessenen Intensitäten können durch einen isotropen, quasiharmonischen Debye‐Waller‐Faktor beschrieben werden. Eine anomale Temperaturabhängigkeit im Bereich des martensitischen Phasenüberganges tritt nicht auf. Der lineare thermische Ausdehnungskoeffizient nimmt im Bereich unter 100 K anomal stark mit der Temperatur ab (und hat ein negatives Vorzeichen bei Temperaturen unterhalb 70 K).
On the growth mechanism of sodalite single crystals grown by the hydrothermal method on single crystal seeds coated with informative informative interfacial layers
Authors: Distler G. I. , Kobzareva S. A. , Lobachev A. N. , Melnikov O. K. , Triodina N. S.
Published: July 2007

The growth mechanism of the early formation stages of sodalite single crystals grown by the method of hydrothermal synthesis on single crystal seeds coated with interfacial layers of polycrystalline silver has been studied at an electronmicroscopic scale. Coating with interfacial layers leads to a very weak adhesion between the overgrown single crystal and the surface of the interfacial layer on top of the seed, thus providing a unique possibility of detaching the overgrown single crystals from seeds and investigating the very early crystallization stages by the morphology of the growth surface. In local microregions of seed surfaces coated with interfacial layers discrete particles arise differing from one another in morphology, this being primarily associated with the electrical heterogeneity of seed surfaces. During crystallization, the space between the discrete particles was filled with the hydrothermal solution which represented a liquid interfacial layer exhibiting informative properties occurred under the influence of electrically active elements of the seed surface. At the boundary separating the liquid interfacial layers with particular informative properties from the rest of the solution volume, at early crystallization stages, together with the formation of discrete particles directly on the coated seed surface, growth of a continuous sodalite single crystal took place. The informative properties of seed surfaces, which are regularly modified due to coating with interfacial silver layers, determine the occurrence on local regions of seed surfaces (under appropriate crystallization conditions) of one or the other polymorphous modification: either hexagonal – cancrinite, or cubic – sodalite.
The development of the rolling texture of f.c.c. metals dependent on relative stacking‐fault energy
Authors: Mücklich A. , Tobisch J. , Kleinstück K.
Published: July 2007

Neutronographic texture investigations are presented for nickel and Co32Ni – the representatives of f.c.c. metals of very high or extremely low relative stacking‐fault energies, resp., as well as for α‐brasses with zinc concentrations between 1 and 4 atomic percent, which are typical for mean values of γ/Gb. The discussion of the results is based on three‐dimensional distribution functions calculated by series expansion. For the main texture components a higher indexing as usually is assumed what is also due to the orientations of these minor components originating in the mechanical twinning. The origin of additional minor components of additional minor components is attributed to the formation of surface textures and recrystallization phenomena. The texture development at extreme relative stacking‐fault energies is associated with cross slip or microtwinning and partial glide, resp.
Emission von Elektronen hoher Energie bei der Zerstörung verschiedener fester Körper
Authors: Chrustalev Ju. A. , Krotova N. A.
Published: July 2007

Es wird der Einfluß der Struktur und der Eigenschaften einer größeren Zahl von Festkörpern auf die Emission von Elektronen hoher Energie bei mechanischer Beanspruchung dargelegt. Die Ursache dieser Feldelektronen‐Emission ist auf die Wirkung von Restlandungen auf der frischgebildeten Oberfläche zurückzuführen, die in den aktiven Zentren zu Feldstärken bis zu 107 V/cm führen.
Temperature distribution in growing semi‐transparent crystals (I). Theory
Authors: Kvapil Jiří , Kubelka J. , Vadura R.
Published: July 2007

Simplified analytical and computational solutions of the temperature distribution in crystals grown by Czochralski method including the temperature difference on the liquid/solid interface are given. The model used is based on experiments with oxide crystals with melting points above 2000 K. Computational solution was more extended because it enables to calculate actual temperature distribution with a relatively small error.
Scandium thin films‐structure and electrical resistance (I). A study on films obtained in a vacuum of 10−5 up to 10−6 Torr
Authors: Loboda V. B. , Protsenko I. E. , Yaremenko A. V.
Published: July 2007

A structure as well as a specific electrical resistance of scandium films having a various thickness (300 up to 2800 Å) obtained at a condensation rate: w⋍ 1 up to 155 Å/s have been studied in the present work. Depending on condensation conditions in films a hydride ScHx, h.c.p. — Sc, or ScHx + Sc alternatively, is formed, a phase containing a distorted hexagonal lattice evolving into the ScHx over a period of a few hours. The ScHx and h.c.p‐Sc change to Sc2O3 when annealed in a vacuum of 5 · 10−5 Torr at a T ≈ 800°C, while in a vacuum of 3 · 10−8 Torr a change to h.c.p.‐Sc with negligible inclusions of oxidic Sc2O3 particles takes place. Formation of oxide is observed also when heating the films with an electron beam directly in a microscope under vacuum of ∼ 8 · 10−5 Torr. The specific electrical resistance ϱ of the film just after a condensation has taken place is approximatly by an order higher as against the ScHx‐ and h.c.p.‐Sc solid specimens. An irreversible gain in said resistance is observed while holding at a room temperature or annealing in a vacuum of 5 · 10−5 Torr, this being associated with absorption of H2, O2 and, possibly, of water steam, and then with formation of Sc2O3. Annealing in a vacuum of 5 · 10−8 up to 10−7 Torr involves a temperature relationship for ϱ of an intricated nature, this being accounted for by a structure transition as follows:

A diode‐effect diminishing with a temperature rise is observed in annealed films.
Some micro‐disk patterns on calcite
Authors: Desai C. C.
Published: July 2007

Microdisk patterns have been produced on {100} cleavage faces of calcite crystals by etching them in a 5 p.c. citric acid solution at 80°C. It is observed that the disks are of different sizes and are distributed all over the face. The microtopography of the disks studied by interferometry has revealed that they are slight elevations on the surface. Various experiments have been performed on matched cleavage faces of calcite and it has been established that the formation of the microdisks is due to protective action of microbubbles formed on the crystal surface during the process of etching. The implications are discussed.
On the growth of one spherical precipitate in an isotropic infinite matrix
Authors: Simmich O. , Löffler H.
Published: July 2007

The growth of one spherical precipitate in an isotropic infinite matrix is treated solving the diffusion equation of the “stationary solution”, i.e. assuming ∂c/∂t = 0, for the general case that the diffusion constant D depends on concentration c. The influence of the resistance of the interface p = p(R) on the growth is considered, too (R radius of the precipitate). It could be shown that the growth law of the particle R ∼ t1/2 holds even foreach D = D(c) used, but it depends sensitively on p = p(R) applied.
On a delayed dislocation emission from hot hardness indentations
Authors: Brenner B. , Wetzig K.
Published: July 2007

The change of the dislocation arrangements around microindentations after indentation test has been investigated by TEM and etching. The indentations were generated on {100} ‐ surfaces of iron single crystals at temperatures between 800 K and 1000 K. The change of the dislocation structure was found to depend strongly on stress and dislocation density in the deformation field. The deformation field especially acts as a dislocation source operating over long periods. The results suggest that the propagation of emitted dislocations is controlled by dragging of Cottrell‐atmospheres of carbon atoms. Conclusions regarding the hardness‐temperature relation in pure iron are drawn.
Mechanical interaction of point defects and volume defects near curved surfaces
Authors: Michael D. , Michel B.
Published: July 2007

The paper deals with the influence of spherical surfaces of solids upon elastic interaction between two point defects or volume defects in an elastic isotropic medium. Formulae have been derived, taking into account the finite dimensions of the defects. This leads to analytic expressions for the energy terms which remain correct (finite) also in the immediate vicinity of the boundary surface of the solid. Hence, they are more sufficient for further application than it is the case with formulae, based on the concept of singular dilatation centres only. The latter are mostly used for investigations of the bulk material, but they lead to divergent expressions for the interaction energy at the surface. Approximation formulae will be given for practical application.
The consistency, coherence and calibration of holistic, decomposed and recomposed judgemental probability forecasts
Authors: Wright George , Saunders Carol , Ayton Peter
Published: July 2007

In this paper we make an empirical investigation of the relationship between the consistency, coherence and validity of probability judgements in a real‐world forecasting context. Our results indicate that these measures of the adequacy of an individual's probability assessments are not closely related as we anticipated. Twenty‐nine of our thirty‐six subjects were better calibrated in point probabilities than in odds and our subjects were, in general more coherent using point probabilities than odds forecasts. Contrary to our expectations we found very little difference in forecasting response and performance between simple and compound holistic forecasts. This result is evidence against the ‘divide‐and‐conquer’ rationale underlying most applications of normative decision theory. In addition, our recompositions of marginal and conditional assessments into compound forecasts were no better calibrated or resolved than their holistic counterparts.

These findings convey two implications for forecasting. First, untrained judgemental forecasters should use point probabilities in preference to odds. Second, judgemental forecasts of complex compound probabilities may be as well assessed holistically as they are using methods of decomposition and recomposition. In addition, our study provides a paradigm for further studies of the relationship between consistency, coherence and validity in judgemental probability forecasting.
The Quadratic Divergencies and Confinement in Non‐Abelian Gauge Theories
Authors: Kaschluhn F.
Published: July 2007

Regularization and renormalization of loop functionals are discussed. A special regularization the so‐called superregularization, is developed which yields neither logarithmic nor linear divergencies when the regularization is removed. All integrals occurring in the perturbation expansion have a well‐defined limit for which gauge invariance can be maintained. Finite subtraction constants referring to the logarithmic and linear divergencies of the originally ill‐defined integrals can be included in their redefined form, the so‐called supervalues of the integrals. On the same basis the derivatives of the loop functionals can be treated. The Makeenko‐Migdal equation is studied in an once‐integrated form. Assuming its singular behaviour to be dominant for large contours the area law is derived. Minimality of the area enclosed by the loop is guaranteed by the Bianchi identities. The string tension involves a subtraction constant of dimension of (length)2 to be determined experimentally.
The use of emergency contraception in young Polish women
Authors: OLSZEWSKI JAROSLAW , OLSZEWSKA HANNA , ABACJEW ANNA , CHMYLKO LUKASZ , GAWORSKA‐KRZEMINSKA ALEKSANDRA
Published: July 2007

Background. The aim of this work was to assess the frequency of use of emergency contraception (EC) and the factors that influence young women in Poland to choose this method of contraception. Methods. The study included 1,154 randomly chosen young women of whom 843 were students of the four largest universities and 311 were pupils aged 18 and over of six randomly chosen secondary schools in the Gdansk region of Poland. A diagnostic review was made by means of a survey based on an anonymous self‐administered questionnaire, that was handed directly to the respondents. The factors affecting EC choice were assessed. The characteristics of women who used EC and those who did not were described and compared. Results. The mean age of the respondents was 21.692.10. In a group of young sexually active women EC was used by only 14%, and among these the frequency with which it had been used varied from once to eight times. The students who most often turned to the EC were from institutions of higher education, came from large cities, and did not have a steady partner. Women in Poland have a general familiarity with the possibility of using EC, but there is insufficient exact knowledge of the way it works, as evidenced by the high proportion of women (68.3%) who regarded the EC as a means of early termination of pregnancy. Conclusions. EC is not routinely employed in Poland. Thus there is a need for thorough and comprehensive sexual education which covers EC.
Counter-urbanisation on the Zambian Copperbelt? Interpretations and Implications
Authors: Potts Deborah
Published: July 2007

For the past 20 years, the population of Zambia has been gradually ruralising, or de-urbanising. For a country which was once seen as emblematic of the process of African urbanisation, and was very often cited (erroneously) as being among the first in sub-Saharan Africa to have reached the stage where over half the population was urban, this is a dramatic shift. This paper has both an empirical and theoretical element. Empirically, it seeks to demonstrate the scale and pattern of the shift within Zambia through careful examination of census data which, although occasionally problematic, are generally sufficiently accurate to provide a basis for analysis. It is shown that counter-urbanisation is mainly characteristic of Copperbelt Province, but that other urban centres have also experienced a marked downturn in their growth rates. Changes in fertility and mortality rates have played a part, but the most important factor is shown to be shifts in migration patterns, with many centres clearly experiencing net out-migration, including that of some urban-born people, as a response to urban economic decline. These dynamics are also discussed theoretically in relation to longstanding debates in African urban studies about the implications of urbanisation and migration dynamics, which date back to the early days of the famous Rhodes-Livingstone Institute which was based in colonial Zambia.