bluuebunny/crossref_metadata_2025 huggingface dataset:
Post-Hypnotic Amnesia as Disrupted Retrieval: A Role-Playing Paradigm
Authors: Wagstaff Graham F.
Published: July 2007

Evans and Kihlstrom (1973) have proposed that the phenomenon of “disrupted retrieval” may be an unobtrusive measure of post-hypnotic amnesia not readily explicable in terms of role-playing or task motivational paradigms of hypnotic behaviour. An attempt was made to test the viability of a role-playing explanation of hypnotic disrupted retrieval by giving equivalent role-playing instructions to carry out hypnosis scale suggestions to unhypnotised subjects. When given the instruction to “pretend” to remember on a few items, unhypnotised subjects recalled items in a random and disorganised manner similar to Evans' and Kilstrom's “hypnotised” subjects; when not given this instruction the unhypnotised subjects showed the sequential organised recall of Evan's and Kihlstrom's hypnotically insusceptible subjects. It was concluded that the phenomenon of disrupted retrieval in post-hypnotic amnesia can readily be explained in terms of the role-playing behaviour implicitly demanded of hypnotically susceptible subjects.
Monkeys' Recognition Memory for Complex Pictures and the Effect of Fornix Transection
Authors: Gaffan David
Published: July 2007

Two monkeys were trained in a running-recognition task with complex pictures. The task was made gradually more difficult by increasing the number of intervening items between the first and second presentation of the same picture. Before undergoing an operation in which the fornix was transected, both monkeys performed above 90% correct even in the most difficult task set, with up to 18 intervening items. After operation neither monkey could reliably perform a much easier task with only 2.7 intervening items on average. This impairment is comparable to that of human amnesic patients in similar tasks.
Cardiac Indices of Infant Speech Perception: Orienting and Burst Discrimination
Authors: Miller Cynthia L. , Morse Philip A. , Dorman Michael F.
Published: July 2007

The present study investigated burst cue discrimination in 3- to 4-month-old infants with the natural speech stimuli [bu] and [gu]. The experimental stimuli consisted of either a [bu] or a [gu] burst attached to the formants of the [bu], such that the sole difference between the two stimuli was the initial burst cue. Infants were tested using a cardiac orienting response (OR) paradigm which consisted of 20 tokens of one stimulus (e.g. [bu]) followed by 20 tokens of the second syllable (20/20 paradigm). An OR to the stimulus change revealed that young infants can discriminate burst cue differences in speech stimuli. Discussion of the results focused on asymmetries observed in the data and the relationship of these findings to our previous failure to demonstrate burst discrimination using the habituation/dishabituation cardiac measure generally employed with older infants.
Discrimination of Word-Like Compound Visual Stimuli by Monkeys
Authors: Gaffan David
Published: July 2007

In Experiment I, two monkeys solved a successive visual discrimination in which the four positive stimuli were the visual arrays RIM, LID, RAD and LAM while the four negative stimuli were RID, LIM, RAM and LAD. In Experiment II the same monkeys first learned a discrimination where the positive stimuli were pairs of letters (e.g. OB and AK) while the negative stimulus was the letter I; in a subsequent generalization test with all four possible pairings of the stimulus elements that had been positive during training (i.e. with OB, AK, OK and AB) the monkeys responded more strongly to the pairs that had been present in initial training. These results were discussed in relation to the theoretical analysis of configurational cues in animal discrimination learning and to the mechanism underlying visual discrimination of words by people.
Isolating the Typicality Effect in Semantic Memory
Authors: McFarland Carl E. , Duncan Edward M. , Kellas George
Published: July 2007

An experiment was conducted to isolate the typicality effect in the overall categorization process. Subjects were required to indicate whether or not a probe word was a member of one of a variable number of categories held in memory. The typicality of the probe word, with respect to its superordinate category, was varied as was the physical quality of the probe. These manipulations were designed to test predictions drawn from Collins and Loftus (1975) and Anderson and Reder (1974), as well as a prediction based on the well-known effect of semantic context on word perception. A fourth prediction was drawn from a proposed model which postulates successive access of categories and locates the typicality effect in a within-category search stage. Typicality proved to be additive with stimulus quality and set size, but interacted with response type. These results were interpreted as support for the successive-access within-category search model while disconfirming the alternative predictions.
Measurement of Trace Strength in Memory for Pictures
Authors: Gaffan David
Published: July 2007

Four experiments using a yes-no recognition task with snapshots examined (1) the effect of presenting not one but two items simultaneously, either both targets or both distractors, for a single judgment at a retention test trial; (2) the rate of forgetting; (3) the interaction between retention interval and the exposure duration at acquisition; (4) acquisition as a function of the number of times a picture was presented. In each case performance was assessed by calculating the discriminability index d′. The results supported the hypotheses that trace strength is lognormally distributed, that forgetting is exponential, and that in acquisition trace strength is a linear function of the number of presentations.
Interference in Pitch Memory as a Function of Ear or Input
Authors: Deutsch Diana
Published: July 2007

An experiment was conducted to investigate the effect of spatial separation on interference effects in pitch memory. Subjects compared the pitches of two tones that were separated by a sequence of eight interpolated tones. It was found that error rates were lower in sequences where the test and interpolated tones were presented to different ears, compared with sequences where they were presented to the same ear; however, this effect of spatial separation was not large. It is concluded that differences in spatial location can enable the focussing of attention away from the irrelevant tones and so reduce their disruptive effect, but that this occurs only to a limited extent.
Neonatal Auditory Habituation and State Change
Authors: Bench John , Mentz Lutgen
Published: July 2007

Groups of newborn babies were exposed to various series of 90 dB SPL noiseband stimuli or to simulated (control) stimuli, while their heart rates (HR) and states of behavioural arousal were monitored. In general the response to stimulation was an accelerative HR change which tended to decrease with repeated stimulation. This seemed to provide evidence of habituation to the auditory stimuli. However, the HR response to sound depended on prestimulus HR and on state, and, when these effects were removed by regression techniques, the progressive decrease in evoked HR with repeated stimulation disappeared, apart from the first few trials. This implied that there was HR habituation to the initial stimuli, but not subsequently, when the apparent HR “habituation” reflected progressive endogenous state changes.
Determinants of Operant Behaviour in Humans: Some Differences from Animals
Authors: Lowe C. Fergus , Harzem Peter , Hughes Sara
Published: July 2007

The performance of human subjects was investigated on fixed-interval (FI) schedules of reinforcement where responses meeting the schedule requirement produced points, later exchanged for money. For one group (the conventional FI condition) presses on a single response-panel were reinforced according to an FI schedule. For another group the procedure was the same as in the conventional FI condition, except that each response also illuminated a digital clock for 0.5 s. A third group responded on two panels; presses on one panel produced reinforcement on an FI schedule, and presses on the second panel illuminated the digital clock for 0.5 s. Responding in the conventional FI condition varied considerably both within and between subjects and different response measures showed no systematic relationship with FI value. For subjects in the other two groups, the pattern of responding on the clock-illuminating panel was scalloped, showing a pause after reinforcement followed by an accelerated response rate; the post-reinforcement pause was an increasing function, and running rate (calculated after excluding the post-reinforcement pause) was a decreasing function, of the value of the FI schedule. The data were compared with results of animal studies on FI schedules and some of the factors which affect performance on these schedules were analysed.
Selective Noise Disturbance of the Information Input in Short-Term Memory
Authors: Salamé P. , Wittersheim G.
Published: July 2007

The present experiment was designed in order to investigate the effects of noise produced intermittently during the input stage of serially displayed visual materials (6-digit lists). These materials were to be memorized and subsequently reproduced on a specially designed keyboard. The four experimental conditions were the following: (1) quiet (Q);

(2) noise uninterrupted during the presentation of each list (CN);

(3) noise emitted simultaneously with each list element (500 ms) (ND);

(4) noise emitted in the interval (140 ms) between each element (NA).

Record was taken of the errors and omissions, of key response initiating times and of hand movement times. As an additional variable, subjects were required to estimate the annoyance induced by each of the four conditions. All noise conditions yielded more errors and omissions than the Q-condition, with the highest rates occurring in the two conditions where noise was superimposed on the digits. Close analysis of the errors showed that the primacy end of the lists was the most affected by noise, whereas keying speed for correct reproductions remained relatively unaffected.

On the other hand, when the speed variable was split into a decision and a motor component, it turned out that the more a condition was judged as annoying, the more the time for response decision was delayed, while the reverse occurred for keying movement times. The latter effect could possibly be ascribed to arousal induced by the three noise conditions. It is argued that noise is liable to affect differently the various components of a task performance, either directly by interference with the intake of pertinent information, or indirectly through induced annoyance or through noise modulated arousal.
Gastric and Plasma Volume in the Control of Milk Intake in Suckling Rats
Authors: Drewett R. F.
Published: July 2007

A method is described for measuring the milk intake of infant rats accurately in short (2-h) tests. It depends upon the prevention of urine loss by occluding the external urethra with collodion during the period of the test. With this method, the role of two internal stimuli—gastric volume and plasma volume—in the control of milk intake were investigated. Saline isotonic with plasma, given by stomach tube in loads of 1.0 ml reduced milk intake. Loads of 1.5 and 2.0 ml prevented also the actual attachment of the pups to the nipple. If, however, the saline was allowed to clear completely from the stomach before the pups were allowed to feed, its effect on milk intake was completely lost. This suggests that any expansion of plasma volume that results from the load after absorption cannot be responsible for inhibiting milk intake. Consistently with this, peritoneal dialysis with the hyperoncotic colloid polyethylene glycol, a procedure which reduces plasma volume, did not stimulate milk intake, though it reduced the rate of urine formation. These results show, therefore, that milk intake responds to changes in gastric volume; but not to changes in plasma volume.
The Overshadowing and Blocking of Punishment
Authors: Claire-Smith R. J. St.
Published: July 2007

Two experiments were undertaken to test the assumption that the outcome of an instrumental contingency depends on the acquisition of signalling properties by the response in the same sense that the acquisition of signalling properties by a stimulus is viewed as determining the outcome of a Pavlovian contingency. The presence coincident with a punished response of a stimulus either previously or preferentially correlated with shock was found to reduce the extent to which punishment suppressed the rate of responding. It was argued that these results, interpreted as indicating the blocking and overshadowing of the response-shock association, were consistent with the assumption tested.
The Interaction of Visual and Motor Memory for Graphic Forms following Tracing
Authors: Hulme Charles
Published: July 2007

Memory for series of abstract graphic forms was tested using a recognition/ reconstruction procedure in two experiments with 8–9-year-old children. The children either looked at the forms and traced around each of them in turn (VT condition), or looked at the forms for an equivalent length of time and pointed to them (V condition). Memory for the forms, but not their order was improved by tracing. The mechanism responsible for this was investigated by comparing the effects of motor and visual interference interpolated between stimulus presentation and recognition testing. Motor interference was most disruptive in the VT condition while visual interference tended to be most disruptive in the V condition. These results support the proposal that tracing produces a distinct motor memory trace and that this additional source of information aids visual recognition.
Control over Sensory Change versus Sensory State Preference in Sensory Contingent Bar Pressing
Authors: Glow Peter H. , Winefield Anthony H.
Published: July 2007

Sixteen rats selected as high responders in a sensory contingent bar pressing situation, were studied when they had free access to four different sensory states. The experimental procedure allowed choices (entries into states) and preferences (as reflected by time spent in states) to be measured simultaneously. Although clear and consistent preferences were observed, they proved to be a relatively weak predictor of choice behaviour. Implications for theories of choice were discussed and the results were interpreted in accordance with the hypothesis that control over the environment has motivational and reinforcing properties.
The Cross-Modal Matching of Brightness to Loudness by Children
Authors: O'Loughlin B. J.
Published: July 2007

According to Stevens’ explanation of cross-modal matching, the recruitment-like effects of masking seen in intramodal loudness judgements should be reflected in a brightness-to-loudness matching task. In an experiment with child observers, this failed to occur. The results are explicable in terms of category mediation of the cross-modal, but not the intramodal, task. In support of this account, it is shown that cross-modal judgements are unaffected by explicit category mediation. However, intramodal judgements, explicitly mediated in the same way, produce a pattern of results similar to those obtained in the cross-modal task. The experiments suggest that cross-modal matching does not provide a useful test of loudness recruitment in the bilaterally hearing impaired.
Transfer of Persistence to the Acquisition of a New Behaviour
Authors: Eisenberger Robert , Carlson Jeffrey , Frank Michael
Published: July 2007

Two experiments tested whether the degree of effort required for the reinforcement of one behaviour would affect the acquisition of a second behaviour. In the first experiment, rats were placed in a conditioning chamber and: (a) were required to press a lever for food pellets on a fixed ratio schedule, (b) received free presentation of the pellets, or (c) did not receive pellets. Next, all rats were rewarded for a new behaviour, round trips across the length of a runway. As predicted, the fixed-ratio group had the greatest shuttle rate. In the second experiment, two groups were required to press a lever, and the number of presses per pellet was varied. For two other groups not required to press the lever, the amount of food presented per approach to the feeder was varied. The greater required number of lever presses and the lesser number of pellets per approach to the feeder produced the higher subsequent shuttle rates. Two alternative explanations were compared: the degree of accustomed effort per reinforcer becomes a learned component of behaviour, or high effort increases the habituation of frustration-produced disruptive responses.
Conversion Errors in Processing Artificial Set Inclusions
Authors: Griggs Richard A. , Osterman Lawrence J.
Published: July 2007

Recent studies on processing linguistically-derived, artificial set inclusions have generally found poor performance on true-false verification tests. Results have indicated logical processing errors, mainly conversions (e.g. if told All As are Bs, then responding true to the test statement All Bs are As). The present experiment attempted to reduce the occurrence of these errors by providing repetitive study of and test on the same set inclusion structure and immediate feedback on each true-false test sentence. Conversion errors were reduced, but only for about one-half of the subjects. Reaction time profiles for these subjects indicated an integrated, holistic representation of the set inclusion information. These reaction time data were like those observed for artificial linear orderings.
Levels of Processing and the Cue Overload Principle*
Authors: Parkin Alan J.
Published: July 2007

This experiment investigates the influence of processing level on the extent of Cue Overload (Watkins and Watkins, 1975, 1976) produced by semantically similar or dissimilar interpolated material. The results showed that semantically similar material only led to increased cue overload if it, itself, was processed semantically. Non-semantic processing of the same types of material failed to reveal any difference between conditions. The results are seen as supportive of the Levels of Processing approach to memory research, since they reinforce the view that different types of orienting task result in qualitative differences in the nature of processing itself. Additionally the results provide some information about the locus of cue overload effects.
Actively Controlling Anticipation of Irregular Events
Authors: Rabbitt Patrick , Vyas Subhash
Published: July 2007

There have been no investigations as to how people respond to sequences of events which occur at brief, unpredictable intervals as in everyday life. Eleven young adults were practised at a two-choice, continuous, serial choice-response task in which intervals between each response and the onset of the next signal (RSIs) varied randomly from trial to trial. On half the trials in each of four conditions the RSI was 20 ms, and on the other trials 200, 400, 800 and 1600 ms respectively. Reaction times fell as RSIs increased from 20-200 ms but thereafter appeared to be unaffected by RSI duration. In the 20/200 and 20/400 ms RSI conditions RT was not affected by transitions between different RSIs but in the 20/800 and 20/1600 ms conditions RTs were faster when the longer RSI recurred on immediately successive trials than if the long RSI followed the short (20 ms) RSI. These results are discussed in terms of a control system model for the way in which subjects actively trade off between their internal performance limitations to optimally meet task demands.
Linguistic Context and the Priming of Semantic Information
Authors: Tabossi Patrizia , Johnson-Laird P. N.
Published: July 2007

Two experiments were carried out to demonstrate that linguistic context (in the form of a sentence) influences the interpretation of unambiguous words. Experiment I established that subjects read a sentence which primes a particular aspect of the meaning of one of the words it contains faster than they read a sentence which primes no particular aspect of the word's meaning. It also showed that subjects produce semantic characteristics of the word faster following the priming sentence than following the sentence that primes no particular semantic component. Experiment II corroborated these results using a task in which subjects read a sentence and then answered a question about the meaning of a word that occurred in it. Given a particular question, responses were faster when it followed a sentence that primed a characteristic relevant to the question than when it followed a sentence that primed no particular characteristic of the word. Responses were reliably slowest when the question followed a sentence that primed a characteristic that was not relevant to the question. Semantic priming is known to affect the identification of words and their disambiguation; the present study confirms that it also affects the specific interpretation of words.
The Intervention That Wasn't: A New Look at the McArthur-Forrest Cyanide Patent Conflict in Western Australia
Authors: Segal Naomi
Published: July 2007

The patented McArthur-Forrest gold extraction process played a significant role in facilitating gold recovery in Western Australia after 1897. The patent-holders failed, however, both to obtain income commensurate with their efforts and to extend their patent rights in Western Australia. This paper revises existing historical accounts of the cyanide royalties dispute in Western Australia in the light of new sources and focuses on industry-state relations and the respective strategic roles that industry and the state played in the resolution of the dispute. The paper also provides a new conclusion to the dispute's resolution in Western Australia.
Experience Matters Most
Authors: Paschke Karl Theodor
Published: July 2007

Even in foreign services that, like Germany's Auswärtiges Amt, follow a generalist principle in their human resources' management, individual careers are shaped by specific experiences. The author uses his own curriculum vitae as a case in point: he served many years in Press and Public Affairs at the German Embassy in Washington DC and as Foreign Office Spokesman in Bonn; he also acquired solid expertise in Personnel and Administration and headed the German Foreign Ministry's Central Department. He was later selected for an assignment as the United Nations' Inspector-General.Paschke feels that interaction with the media, administrative matters and oversight in international organizations are as challenging and attractive as any other diplomatic activity. His professional expertise continues to be in demand even after his retirement.
A self‐tuning controller for mimo non‐linear systems
Authors: Agarwal Mukul , Seborg Dale E.
Published: July 2007

A new self‐tuning control (STC) strategy for non‐linear, multi‐input/multi‐output control problems is proposed. This strategy is applicable to a broad class of non‐linear systems, which can include any nonlinear functions of the old inputs and outputs as well as the products of these functions and any powers of the most recent inputs. Simulation results for a two‐link robot manipulator demonstrate that the new non‐linear STC strategy provides significant improvement over conventional STCs based on linear models.
Comparative 13C‐NMR and matrix‐assisted laser desorption/ionization time‐of‐flight analyses of species variation and structure maintenance during melamine–urea–formaldehyde resin preparation
Authors: Despres A. , Pizzi A. , Pasch H. , Kandelbauer A.
Published: July 2007

The preparation of an industrially used sequential formulation of a melamine–urea–formaldehyde resin was followed by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry and 13C‐NMR analysis. The analysis allowed us to identify and follow the appearance, increase, decrease, and disappearance of a multitude of chemical species during the preparation of both the initial urea–formaldehyde (UF) phase of the reaction and the subsequent reaction of melamine with the UF resin that formed. The analysis indicated that (1) the increase and decrease in the species that formed proceeded through a cycle of the formation and degradation of species occurring continuously through what appeared to be a series of complex equilibria, (2) even at the end of the reaction a predominant proportion of methylene ether bridges was still present, (3) some small proportion of methylene bridges already had formed in the UF reaction phase of the resin even under rather alkaline conditions, and (4) the addition of melamine to the UF prepolymer induced some noticeable rearrangement of methylene ether bridges to methylene bridges. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Diallyl bisphenol A—novolac epoxy system cocured with bisphenol‐A‐bismaleimide—cure and thermal properties
Authors: Ambika Devi K. , Reghunadhan Nair C. P. , Ninan K. N.
Published: July 2007

Novolac epoxy (EPN)—2,2′‐diallyl bisphenol A (DABA) resin system was modified by cocuring it with bisphenol A bismaleimide (BMI). Molar concentration of BMI in the stochiometric blend of EPN and DABA was varied from 0.5 to 2.0. The cure optimization was done using DSC, IR spectroscopy, and rheological studies. The curing proceeded by phenol‐epoxy and Alder‐ene reactions. The performance of the ternary Epoxy‐Allyl phenolic‐Bismaleimide system was evaluated through their thermal and dynamic mechanical characterization. BMI improved the overall thermal stability and the modulus of the resultant composites. The increase in BMI concentration in the system resulted in enhanced glass transition temperature with a consequent improvement in high temperature performance typically estimated by their lap shear strength at high temperatures. The high temperature performance of the epoxy‐phenol‐bismaleimide (EPB) system was found to be far superior to the epoxy‐phenol (EP)system. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Poly(N‐isopropylacrylamide‐co‐poly(ethylene glycol))‐acrylate simultaneously physically and chemically gelling polymer systems
Authors: Cheng Vicki , Lee Bae Hoon , Pauken Christine , Vernon Brent L.
Published: July 2007

In an effort to create an in situ physically and chemically cross‐linked hydrogel for in vivo applications, N‐isopropylacrylamide (NIPAAm) was copolymerized with poly(ethylene glycol)‐monoacrylate (PEG‐monoacrylate) and then the hydroxyl terminus of the PEG was further modified with acryloyl chloride to form poly(NIPAAm‐co‐PEG) with acrylate terminated pendant groups. In addition to physically gelling with temperature changes, when mixed with a multi‐thiol compound such as pentaerythritol tetrakis 3‐mercaptopropionate (QT) in phosphate buffer saline solution of pH 7.4, this polymer formed a chemical gel via a Michael‐type addition reaction. The chemical gelation time of the polymer was affected by mixing time; swelling of the copolymer solutions was temperature dependant. Because of its unique gelation properties, this material may be better suited for long‐term functional replacement applications than other thermo‐sensitive physical gels. Also, the PEG content of this material may render it more biocompatible than similar HEMA‐based precursors in previous simultaneous chemically and physically gelling materials. With its improved mechanical strength and biocompatibility, this material could potentially be applied as a thermally gelling injectable biomaterial for aneurysm or arteriovenous malformation (AVM) occlusion. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Ein Zuverlässigkeitskriterium für Polfiguren von Texturen kubischer Kristalle
Authors: Bunge Hans‐Joachim
Published: July 2007

Es wird eine Methode angegeben, die Genauigkeit von Polfiguren für Texturen kubischer Kristalle abzuschätzen. Dazu werden gewisse Integrale mit den Mittelwerten der Polfiguren verglichen.
Über die Elektrokristallisation des Wismuts
Authors: Stojčev N. , Budurov St. , Kirov G. , Jurukova I.
Published: July 2007

In der vorliegenden Arbeit werden die Anfangsformen des Wachstums halbkugelförmiger Wismut‐Einkristalle bei Elektrokristallisation aus Bi(NO3)3‐Lösungen studiert. Die Versuche wurden bei 20 °C und Stromdichten zwischen 0,05 und 12 mA/cm2 durchgeführt. Die experimentell erhaltenen Anfangsformen des Wachstums stimmen gut mit der Gleichgewichtsform der Wismutkristalle überein, die von den Autoren nach der Methode von Stranski und Kaischew bestimmt wurde.
Über die Definierung der spezifischen Oberflächenenergien bei endlichen Kristallen
Authors: Kaischew R. , Nenow D.
Published: July 2007

Auf Grund eines Kristallmodells, das die Form eines Parallelepipeds besitzt, wird gezeigt, daß bei endlichen Kristallen die Definierung der von den Kristallabmessungen abhängigen spezifischen Oberflächenenergien auf verschiedene Weise möglich ist. Die spezifischen Oberflächenenergien, die mit Hilfe der von Stranski erweiterten Methode von Born und Stern definiert werden, sind als integrale Werte zu betrachten. Es können aber auch, ähnlich wie bei den Flüssigkeiten, differentielle spezifische Oberflächenenergien definiert werden, für die ein der Wulffschen Regel formal analoger Ausdruck gültig ist.
Die Bestimmung der Kristallinität von Schlacken
Authors: Engel Aribert
Published: July 2007

Für die Beurteilung der Verwendungsfähigkeit glasig erstarrter Stoffe, wie z. B. Hochofenschlacken, ist die Kenntnis ihrer chemischen Zusammensetzung und der Kristallinität unerläßlich. Es wird ein lichtoptisches Integrationsverfahren beschrieben, bei dem die Anisotropieeffekte der kristallinen Bestandteile durch eine neuartige Meßanordnung bestimmt werden.
Über den Einfluß der aliphatischen Carbonsäuren auf die Wachstumsgeschwindigkeit von KBr‐Kristallen
Authors: Bliznakov G. , Nikolaeva R.
Published: July 2007

Es wurde festgestellt, daß die Wachstumsgeschwindigkeit der {100}‐Flächen von KBr‐Kristallen unter dem Einfluß von aliphatischen Carbonsäuren abnimmt, und zwar nach der von einem der Autoren früher abgeleiteten Abhängigkeit (Bliznakov 1954; 1958). Säuren, die eine größere Anzahl von CH2‐Gruppen enthalten, weisen eine stärkere passivierende Wirkung auf. Die Isothermen der Passivierung wurden bei einigen Temperaturen aufgenommen. Aus den experimentellen Daten wurden die Werte der Adsorptionswärme der Beimengungen (Säuren) an den aktiven Wachstumszentren der {100}‐Flächen von KBr‐Kristallen berechnet. Säuren, die stärker adsorbiert werden, haben eine stärker passivierende Wirkung.
Über die Einkristallzüchtung von Vanadinpentoxid aus der Schmelze
Authors: Kleber W. , Ickert L. , Grasme K. , Riedel G.
Published: July 2007

Es wurden Züchtungsversuche von Vanadinpentoxid aus der Schmelze mit Hilfe einer Apparatur nach Bridgman und Stockbarger sowie nach dem Zonenschmelzverfahren unter Sauerstoff durchgeführt. Die Qualität der gewonnenen Einkristalle wurde mit der Ätzmethode und mit einer röntgentopographischen Methode untersucht. Es zeigte sich, daß die Einkristalle, die nach dem Zonenschmelzverfahren unter Sauerstoff hergestellt worden waren, weniger fehlerhaft gebaut sind als jene, die nach Bridgman‐Stockbarger gezogen wurden.
Fadenförmige Einkristalle von Magnesiumoxid
Authors: Budnikov P. P. , Sandulov D. B.
Published: July 2007

Durch die Transportreaktionen magnified image wurden fadenförmige Magnesiumoxid‐Einkristalle gezüchtet. Die optimale Temperatur in der Reaktionszone beträgt 1600–1700 °C; das Kristallwachstum des MgO auf einem Substrat aus polykristallinem Magnesiumoxid erfolgt bei 1400–1600 °C. Die Länge der Kristalle erreichte 30 mm; ihre Dicke lag zwischen einigen Zehntel und 50–100 μm. Die 10–50 μm dicken Kristalle wachsen in Richtung 〈100〉, die Wachstumsrichtungen der dünnen Kristalle (0,1–1 μ), die aus Präzisions‐Elektronenbeugungsaufnahmen bestimmt wurden, sind 〈100〉 und 〈111〉.

Die Zerreißfestigkeit der Kristalle betrug für Kristalle von 2 μm Dicke bei der ersten Belastung 350 kp mm−2; bei der zweiten Belastung desselben Kristalls stieg die Festigkeit auf 510 kp mm−2; bei der dritten auf 790–800 kp mm−2.
Dendritisches Wachstum beim Gastransport halbleitender Stoffe
Authors: Sirtl E. , Zaminer Ch.
Published: July 2007

Die Vorraussetzungen zur Bildung von Dendriten an der Phasengrenze gasförmigfest werden umrissen und die verschiedenen Bauprinzipien solcher Kristallindividuen diskutiert. Bei hohen Übersättigungen können Längen‐ und Dickenwachstum als Primär‐ bzw. Sekundärstadium getrennt betrachtet werden. Die verschiedenen Stadien des Kantenwachstums beim Verdickungsprozeß lassen sich anhand geätzter Querschliffe verfolgen.
Kraterbildung und Deformationsstrukturen in Antimoneinkristallen durch Laserbearbeitung
Authors: Meyer K. , Meier W.
Published: July 2007

Es wird die Wirkung von fokussierten Laserstrahlen auf (111)‐Spaltflächen von Antimon im Hinblick auf die Bildung eines Verdampfungskraters und die Entstehung von Deformationsstrukturen durch Translations‐ und Zwillingsgleitung systematisch unter Veränderung der Kristalltemperatur (−100°C bis +200°C) und der Energiedichte (20 bis 80 Ws cm−2) untersucht. Die Bildung eines Verdampfungskraters wird theoretisch gedeutet und eine befriedigende Übereinstimmung mit dem Experiment erzielt. Die Berechnung der thermischen Spannungen ermöglicht die Deutung der beobachteten Versetzungsstrukturen. Die Zwillingsbildung wird zurückgeführt auf den Rückstoßdruck der verdampfenden Antimonatome.

Abschließend werden die laserinduzierten und die durch mechanische Bearbeitung erzeugten Deformationsstrukturen verglichen.
Adsorption von Harnstoff und Bleichlorid and NaCl‐Würfeln und ‐Oktaedern
Authors: Karge H.
Published: July 2007

Von Hille und Jentsch mitgeteilte Befunde, nach welchen die Adsorption von Harnstoff sowie HgCl2 an {100}‐ und {110}‐ bzw. {110}‐Flächen des Steinsalzes „negativ”︁ ist (Anreicherung von Wasser in der Grenzschicht), erwiesen sich als vorgetäuscht durch Harnstoff‐ bzw. HgCl2‐Verluste bei der Versuchsdurchführung.

Bei Ausschaltung der Fehlerquellen ergab sich sowohl im Falle von NaCl/Harnstoff als auch im Falle des ebenfalls untersuchten Systems NaCl/PbCl2 eine positive Adsorption des trachtändernden Lösungsgenossen an den {111}‐Flächen. Die {100}‐Flächen zeigten keine meßbare Adsorption.

Für die Oktaeder wurde die Adsorption aus der den trachtändernden Lösungsgenossen enthaltenden Mutterlösung, und zwar unmittelbar nach Entstehung der Kriställchen, ermittelt. Dabei wurde festgestellt, daß der trachtändernde Lösungsgenosse nicht nur adsorptiv an der Oberfläche der Oktaeder angereichert, sondern auch im hohen Maße eingebaut wird.
Über die Wachstumsformen von Cäsiumeinkristallen aus der Gasphase
Authors: Stojčev N. , Budurov S. , Peneva S.
Published: July 2007

Es werden die Wachstumsformen kugelförmiger Cäsiumeinkristalle aus der Dampfphase bei einem Übersättigungsverhältnis s von 1,02 bis 56 untersucht. Bei diesen Übersättigungen treten an der Anfangswachstumsform nur die Flächen {110} auf. An den Endwachstumsformen erscheinen auch die Flächen {211}. {100}‐ und {111}‐Flächen wurden nicht beobachtet.

Die Ergebnisse werden vom Standpunkt der Theorie von STRANSKI und KAISCHEW diskutiert und gedeutet.
Stresses in Silicon after Boron Diffusion (I). Determination of Residual Stresses in Boron‐diffused Silicon Slices Using Lang's Method
Authors: Brümmer O. , Höche H. R.
Published: July 2007

The radii of curvature of specially prepared specimens are determined by means of the Lang method, from which qualitative and quantitative information can be obtained on stresses in boron‐diffused silicon slices. It is possible to give an estimation of the serveral causes of the stresses.
The structure of epitaxially grown layers and the electrical parameters of p–n junctions formed on them
Authors: Pfeifer J. , Gútai L. , Haraszthy É. Sz.
Published: July 2007

Germanium layers were evaporated onto p‐type substrates in oil diffusion pumped systems under pressures varying between 3 × 10−5 and 1 × 10−8 torr. Evaporation parameters: CP‐4 etched (111) Ge substrate; 810°C substrate temperature; condensation rate: 3–5 μmin−1; layer thickness: 15–25 μ. Structural properties were determined by etching rate, microscopy and electron diffraction examinations. Graded p–n junctions were formed by diffusion into the layers. I–V, C–V characteristics of the junctions and storage‐time were determined. Hole concentrations between 1 × 1018 and 4 × 1015 cm−3 were found. The lifetime of the minority carriers was found to be 0.1–1 μs, depending on the pressure during evaporation. It is suggested, that the interfaces between layers and substrates possess the worst structural properties and that the electrical properties of p–n junctions are much more characteristic of the layer quality than the results of the proper structural investigations.
Die Abhängigkeit der Aktivierungsenergie des Kristallwachstums von der Temperatur
Authors: Meleško L. O.
Published: July 2007

Es wird eine Methode zur Bestimmung der Temperaturabhängigkeit der Aktivierungsenergie der Grenzschicht‐Selbstdiffusion im Bereich des abfallenden Teils des Verlaufs der Funktion v = f(ΔT) (v ist die lineare Kristallwachstumsgeschwindigkeit, ΔT die Unterkühlung der Schmelze) beschrieben, ein entsprechender analytischer Ausdruck abgeleitet und experimentelle Daten für Antipyrin, Benzophenon und Kodein mitgeteilt.
Untersuchungen zur orientierten Verwachsung von Gold mit Alkalihalogeniden im UHV
Authors: Harsdorff M. , Adam R. W. , Schmeisser H. H.
Published: July 2007

In der vorliegenden Arbeit wird die orientierte Verwachsung von Gold mit Alkalihalogeniden unter den sauberen Bedingungen des UHV untersucht. Dabei ergab sich im Gegensatz zu den im HV erhaltenen Ergebnissen, daß Au mit NaCl nicht vollständig orientiert verwächst, die Epitaxietemperaturen bei den weiterhin untersuchten Unterlagen (KCl, KBr, KJ) für Au erheblich höher liegen als bei UHV‐Experimenten und eine Funktion der Aufdampfrate sind. Der Einfluß der durch die Kondensationsenergie verursachten lokalen Temperaturerhöhung, von im UHV aufgedampften amorphen Zwischenschichten und der Art der Bedampfung (kontinuierlich bzw. diskontinuierlich) wird untersucht.
Die Ausbildung der Textur von vakuumkondensierten In‐Schichten
Authors: Pócza J. F. , Barna Á. , Barna P. B.
Published: July 2007

Die im Flüssigkeitszustand kondensierenden Partikel besitzen in der ersten Phase der Kristallisation eine ungeordnete Orientierung im Temperaturbereich zwischen dem Schmelzpunkt und der Zimmertemperatur.

Eine ausgezeichnete Orientierung mit der Achse ⟂ (111) erscheint erst in einer späteren Phase der Koaleszenz, in der Kristallite eine bestimmte Größe erreichen.

Die kritische Massendicke einerseits und die kritische Korngröße andererseits, bei denen die ausgezeichnete Orientierung beginnt, wurde in Abhängigkeit von der Temperatur des Substrates gemessen.

Die zum Auftreten der ausgezeichneten Orientierung gehörende Mindestkorngröße nimmt mit zunehmendem Partialdruck des Sauerstoffes monoton ab. Man kann eindeutig feststellen, daß die Wachstumstextur durch eine Umkristallisation, die bei der Koaleszenz vor sich geht, verursacht wird.
Apparatus for dynamic piezooptic investigations on semiconductors in the temperature region between 100 and 500°K
Authors: Ochel M.
Published: July 2007

A sampleholder for applying uniaxial, periodic pressure on small crystals is described. The arrangement allows temperature variation between 100 and 500°K and was developed for piezooptical measurements on semiconductor single crystals with dimensions of about 17×4×0, 8 mm3. The principal design of the apparatus for piezoabsorption measurements is given. ‐ The piezoabsorption curves are well reproducible.
Zone refining of alkali chlorides and bromides
Authors: Voszka R. , Raksányi K. , Berkes L.
Published: July 2007

The authors show that the zone‐refining method used by them previously in the case of KCl is effective for KBr, RbCl, RbBr and CsCl as well. The attainable purity for M2+ is better than 10−8 mole/mole. In the case of NaCl and NaBr they propose to replace Ca2+ ions with Ba2+ ones by chemical means before zone melting. By this method NaCl single crystals of 2 × 10−7 mole/mole purity were produced.
Über die Rolle der Alkalimetalle beim Aufbau der Silicate und Germanate unter hydrothermalen Bedingungen
Authors: Lobačev A. N. , Kusmina I. P. , Demjanez L. H. , Iljuchin V. V. , Belov N. V.
Published: July 2007

Die kristallchemische Analyse der Germanante A3HG7O16 · 4 H2O, A2Ge4O9, A4Ge9O20,A2MeGeO4, wo A = Li, Na, K, Cs; Me = Zn, Cd, Co, Ni sind (Germanium kann eine doppelte Rolle spielen, als Kation – Ge oktaedrisch koordiniert – und als Anion tetraedrisch koordiniert), die mit Hilfe von Kristallisationsmethoden aus der Schmelze oder aus Lösungen bei Temperaturen unterhalb des Siedepunktes von Wasser synthetisiert wurden, gestattet mit einem bestimmten Wahrscheinlichkeitsgrad das Verhalten der Alkaligermanate unter hydrothermalen Bedingungen vorauszusagen. Theoretische Aussagen über die Stabilität der Germanatphasen auf der Grundlage der Kristallchemie erhärten die Ergebnisse der Hydrothermalsynthese bei Temperaturen von 200–450°C.
Untersuchungen zur chemischen Homogenität nickeldotierter Kupfereinkristalle nach Wärmebehandlung
Authors: Hildebrand Helga
Published: July 2007

Mit Neutronen bestrahlte einkristalline Cu‐0,2 At.‐% Ni‐Proben wurden autoradiographisch und mittels γ‐Spektroskopie in bezug auf die Nickelverteilung im Kristallquerschnitt und über der Kristallänge untersucht. Obwohl die Versetzungsbewegung während der langdauernden Wärmebehandlung zur Herabsetzung des Versetzungsinhaltes radial zur Kristallachse in Richtung zur Oberfläche abläuft, wird das Nickel nicht an der Oberfläche angereichert. Jedoch läßt sich in den nach Bridgman gezogenen Kristallen eine Eisenanreicherung in dem zuletzt erstarrenden Kristallende als Folge des gerichteten Kristallwachstums nachweisen. Untersuchungen mit der Elektronenstrahlmikrosonde stützen diese Befunde. Damit ist eine langdauernde Wärmebehandlung bei nickeldotierten Kupferkristallen anwendbar, um Kristalle mit hinreichend niedriger Versetzungsdichte und chemischer Homogenität zu erhalten.
Umwandlung des Fe3S4 von Fd3m nach Pa3, P4/nmm bzw. P63/mmc beim hydrothermalen Prozeß
Authors: Yamaguchi S. , Wada H.
Published: July 2007

Beim hydrothermalen Prozeß der Fällung von Eisensulfid entstehen u. U. Greigit (Raumgruppe: Fd3m), Pyrit (Pa3), Mackinawit (P4/nmm) und Pyrrhotin (P63/mmc). Mit Greigit entsteht auch Pyrit, wenn das Reaktionsgefäß beim hydrothermalen Prozeß nicht schnell von 192°C bis auf Zimmertemperatur, sondern langsam abgekühlt wird. In diesem Fall bilden Greigit und Pyrit teilweise einen Mischkristall. Mechanische Gemenge von Greigit‐Mackinawit und von Greigit‐Pyrrhotin entstehen beim hydrothermalen Prozeß unterhalb bzw. oberhalb 192°C. Reinen Greigit kann man nur durch schnelle Abschreckung des Reaktionsgefäßes von 192 auf 10°C darstellen.
Investigation of the kinetics of the inversion of modifications sphalerite—wurtzite in zinc sulphide
Authors: Sirota N. N. , Sapelkina V. P.
Published: July 2007

The kinetics of isothermal transition of wurtzite into sphalerite at temperatures below the equilibrium temperature of transition (T < Tk) and sphalerite into wurtzite at (T > Tk) is studied.

The diagrams of stability of the overheated and supercooled phases are drawn, and the temperature of the equilibrium transition is defined more precisely.
Included and occluded grains in iron single crystals
Authors: Kadečková S. , Přádná R.
Published: July 2007

The paper presents some experimental results concerning the occurrence of stray grains in high‐purity iron single crystals grown by the strain‐anneal method. The experimental results indicate that the stray grains are either the unabsorbed grains from the polycrystalline matrix with twin orientation or true annealing twins. The iron crystals with a small number of stray grains can be prepared when a steep temperature gradient is used during growth.
Anomale Wärmeausdehnung von V2O5
Authors: Filatov S. K.
Published: July 2007

Mit Hilfe der Hochtemperatur‐Diffraktometrie wurde der stark anisotrope Charakter der Wärmeausdehnung des kristallinen Vanadiumpentoxids festgestellt. Im Intervall von 0 bis 685 °C betragen die Ausdehnungskoeffizienten αa = 0,4–7,9, αb = –2,0, αc = 45,8–44,4 (· 10−6 grd−1). Eine Erklärung für diese Anomalie kann man in der erhöhten Dynamik des Koordinationsfünfecks des Sauerstoffs um das Vanadium suchen, das die Struktur des V2O5 aufbaut.

Die Ergebnisse der Pulverdiffraktometrie wurden durch Reflexionen im Großwinkelbereich an Textur‐Präparaten präzisiert, die auf der Fläche des Kristallhalters präpariert wurden.
Ätzuntersuchungen an Alaunen mit nichtwäßrigen Lösungsmitteln. Will Kleber zum Gedenken
Authors: Hähnert I.
Published: July 2007

Die Ätzuntersuchungen wurden an einkomponentigen Alaunen (KAl‐, NH4Al‐ und KCr‐Alaun) und Mischkristallen (K(Al, Cr)‐Alaun) durchgeführt. Beste Ergebnisse bezüglich der Grubenausbildung und ihrer Reproduzierbarkeit wurden mit alkoholischer Weinsäure als Ätzmittel erhalten. Die Beziehung von Ätzgruben zu Versetzungen wurde an KAl‐Alaunkristallen untersucht. Eine Verbindung von mikroskopischen Einschlüssen mit Versetzungen mußte nach den Ätzergebnissen und den bestehenden Vorstellungen zu deren Bildungsmechanismus ausgeschlossen werden.
Untersuchungen zum orientierten Aufwachsen von Silberschichten auf Muskovit
Authors: Dobbert P. , Neumann H.‐G. , Preuschhof H. J.
Published: July 2007

In der vorliegenden Arbeit wird der Einfluß einer amorphen Kohlezwischenschicht auf das orientierte Aufwachsen von Silber auf Muskovit untersucht. Es wird nachgewiesen, daß das einkristalline Substrat bis zu Kohleschichtdicken von 200 Å orientierend auf die entstehende Silberschicht wirkt.
Zur Auflösungsgeschwindigkeit von Kristallen in Wasser. Will Kleber zum Gedenken
Authors: Haussühl S. , Müller W.
Published: July 2007

Die Auflösungsgeschwindigkeit in Wasser wurde an 38 verschiedenen Kristallarten mit einer neuen, einfachen Methode gemessen. Ein dünner Wasserstrahl wird unter festen Bedingungen gegen die Oberfläche gerichtet. Der durch eine bestimmte Lösungsmittelmenge erzeugte Gewichtsverlust gibt ein Maß für die Auflösungsgeschwindigkeit. Die NERNST‐BRUNNERsche Beziehung beschreibt die Abhängigkeit der Auflösungsgeschwindigkeit von der Löslichkeit, dem Diffusionskoeffizienten, der Viskosität und der Temperatur in befriedigender Weise. In isotypen Kristallen verhalten sich Gitterenergie und Auflösungsgeschwindigkeit gegenläufig. Hauptwachstumsflächen zeigen in fast allen Fällen ein Minimum der Auflösungsgeschwindigkeit. Zusätze in geringen Konzentrationen verursachen eine starke Hemmung ebenso wie bei Wachstumsexperimenten, wenn sie schwerlösliche Verbindungen mit dem Substrat bilden. Die Korrespondenz zwischen Wachstum und Auflösung tritt in fast allen Erscheinungen hervor.
Über P.B.C.‐Vektoren und ihre Bedeutung für das Kristallwachstum, speziell beim Silicium
Authors: Schreckenbach M.
Published: July 2007

Es wird gezeigt, wie man mit der P.B.C.‐Methode für das Kristallwachstum einige allgemeine Gesichtspunkte gewinnen kann. Dabei wird der Begriff „Richtkraft”︁ vorgeschlagen, der verschiedene Kristallsysteme zu vergleichen erlaubt, namentlich hinsichtlich der Aussichten auf Herstellung versetzungsarmer Kristalle.
Untersuchung der Ausscheidungsverhältnisse von schmelzgegossenen hochaluminiumoxidhaltigen feuerfesten Materialien
Authors: Schröder W.
Published: July 2007

Es wird der Zusammenhang zwischen den Ausscheidungsbedingungen und dem Gefüge von schmelzgegossenen hochaluminiumoxidhaltigen Steinen untersucht. Dabei zeigt sich, daß Steine mit einem geringen Glasphasenanteil einem relativ langsamen Abkühlprozeß unterworfen werden müssen, damit ein zu stark gestörtes Wachstum der Korundkristalle in größeren Bereichen des Steines verhindert wird. Ein schneller Erstarrungsprozeß durch rasches Abkühlen führt nicht zur definierten Dendritenbildung und Herausbildung eines stabilen Gleichgewichtszustandes.