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  • 1
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Thermal Behaviour of Sulfates. III. The Behaviour of CdSO4 at High TemperatureThe behaviour of CdSO4 was studied by means of high temperature Guinier photographs in the temperature range of 20 to 960°C. Except N-CdSO4 which is the thermodynamically stable modification at STP, there are 3 high temperature modifications (M, H1 and H2-CdSO4) of which only metastable M-CdSO4 can be obtained kineticly stable at room temperature. The lattice constants and the structure type of H1- and H2-CdSO4 were determined. The structure of H1-CdSO4 is closely related with that of N-CuSO4 but in difference of N-CuSO4 it has a superlattice. H1-CdSO4 crystallizes orthorhombic with a325°C = 17.80 Å, b325°C = 7.35 Å, c325°C = 4.84 Å, Z = 8.H2-CdSO4 crystallizes hexagonal with a850°C = 5.01 Å, c850°C = 7.64 Å, Z = 2 in a modified NaKSO4 structure type (space group P 3m 1) with Cd2+ only in the Na+ positions. The temperatur and sequence of transitions as well as the thermal expansion of N- and M-CdSO4 was determined
    Notes: Mit Heizguinieraufnahmen wurde das Verhalten von CdSO4 im Temperaturbereich von 25-960°C untersucht. Außer der bei Raumtemperatur thermodynamisch stabilen Modifikation (N-CdSO4) existieren 3 Hochtemperaturmodifikationen (M, H1 und H2-CdSO4), von denen nur das metastabile M-CdSO4 bei Raumtemperatur kinetisch stabil zu erhalten ist. Metrik und Strukturtyp von H1- und H2-CdSO4 wurden bestimmt. H1-CdSO4 ist mit N-CuSO4 strukturverwandt, besitzt jedoch eine Überstruktur. Es kristallisiert orthorhombisch mit a325°C = 17,80 Å, b325°C = 7,35 Å, c325°C = 4,84 Å, Z = 8. H2-CdSO4 kristallisiert hexagonal mit a850°C = 5,01 Å, c850°C = 7,64 Å, Z = 2 in einem modifizierten NaKSO4-Typ (RG: P 3m 1); Cd2+ nur auf Na+-Punktlagen. Temperatur und Verlauf der Umwandlungen sowie die thermische Dilatation von N- und M-CdSO4 wurden bestimmt.
    Additional Material: 4 Ill.
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  • 2
    ISSN: 1573-3297
    Keywords: mating activity ; Drosophila persimilis ; chromosomal variants ; homokaryotypes ; heterosis for mating activity ; populational variation in mating activity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Previous tests for mating activity ofDrosophila persimilis homokaryotype KL (Klamath) and MD (Mendocino) chromosomal arrangements (northern California population: Redwoods) had shown KL to mate faster on the average than MD in homogamic tests. A strain (double-cross hybrid of four KL lines from the same population) with reliable high mating activity was developed for testing the sexes separately. Five pairs of KL-MD homokaryotype strains were chosen to be tested by the criterion that each pair had been derived from a separate wild KL/MD progenitor. Strains were crossed within arrangements in a diallelic design (20 inter- and five intrastrain crosses tested in 16 replicates per cross) to provide mating activity indices of four sets: KL females, KL males, MD females, MD males. Mating tests employed ten virgin experimental flies with ten tester (double-cross hybrid) flies of the opposite sex in 30-min observation periods. All flies were matured for 5 days at 25°C before testing. Among parental strains, females were consistently higher in mating activity than males for both KL and MD arrangements. Most interstrain hybrids were heterotic, with KL and MD females not significantly different. However, hybrid MD males displayed greatest variation and had lowest mating activity, while KL males were the least variable and highest in mating activity. With heterosis in the hybrids, there was no predictability (additivity) from performance of parental strains to hybrid offspring. Mating activities of the two sexes were uncorrelated, indicating either that the sexes have independent genetic systems controlling mating activity or that the expression of the same genetic system is influenced by sex. Since the hybrid males of the two karyotypes displayed different courtship activity while the females were at about an equal level of receptivity, intrasexual selection among males is likely to be important in nature.
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  • 3
    ISSN: 1573-3297
    Keywords: minority mating advantage ; Drosophila melanogaster ; mating behavior ; male courtship cues ; habituation by female
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Alleles at the brown locus ofDrosophila melanogaster combined with homozygous scarlet provide a useful model to demonstrate minority advantage of males in mating. Heterozygotes with orange (O) eyes equal in numbers to homozygotes with red (R) eyes (10∶10 in both sexes) displayed no bias favoring either eye color, but each eye color was favored when males occurred in a minority ratio (2∶18). In direct observation of single females with equal numbers of males (3∶3) as controls,O males courted less and more slowly thanR males, but females mated with either type without bias. When unequal (4∶1), the minority males were successful at more than twice the frequency expected. Whether successful or not, the minority males did not change their level of courtship, and thus cannot be said to compensate for their frequency in any way. The time between first courtship and mating was less for the minority males than for the majority males. We discard the hypothesis that the minority male will be accepted immediately or ahead of a majority male, because the opposite tended to occur: that if a minority male courted first he was less likely to be successful than if he waited until the majority courted. Our results then are in conformity with the hypothesis that a female samples males and their courtship cues, thus becoming habituated to the majority of the first courting male, but she accepts a male with a cue different from that which she originally detected but avoided. That male is most often the minority.
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  • 4
    ISSN: 1573-0581
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract The Tamayo transform fault occurs at the north end of the East Pacific Rise where it enters the Gulf of California. The two deep-tow surveys reported here show that the transform fault zone changes significantly as a function of distance from the spreading center intersections. At site 1, near the intersection, one side of the fault is young and the fault zone is narrow and well-defined. Strike slip occurs in a zone approximately 1-km wide suggesting a correspondingly narrow zone of decoupling between the Pacific and North American plates. On the young side of the strike-slip zone, normal faults occur along shear zones which are 45°–50° oblique to the transform strike. They occur parallel to the short axis of the strain ellipse for transform fault strain here, i.e., perpendicular to the least compressive stress. The transform walls are formed by normal faulting as has been pointed out in previous detailed surveys. Here, however, the age contrast of 2.5 m.y. across the transform valley is apparent in the morphology of the normal fault scarps. While the scarps are steep and well-defined on the young side, the scarps on the older side have gradual 10°–30° slopes and appear to be primarily talus ramps. Apparently, the scarps have been tectonically eroded by continued strike slip activity after the initial stages of normal faulting. Thus, transform valleys should be quite asymmetric in cross-section where there is a significant age contrast and one side is less than approximately 0.5 m.y. old. Also, along older sections of the transform valley walls, normal faulting may not be at all obvious due to degradation of the scarps by tectonic erosion. This phenomenon makes the likelihood of transform faults providing ‘windows’ into the oceanic crust most unlikely except in special cases. The picture of transform deformation is more complex at site 2 in the central portion of the fault where both sides of the fault are greater than 1 m.y. old. Here the transform valley is wider (25–30 km as opposed to 2–5 km). There is no clear simple zone of strike slip tectonics. In fact, the only clear evidence for deformation is the intrusion of magmatic or serpentinite diapirs through the sediments of the transform valley floor. The diapirs have deformed the turbidite layers flooring the valley and in one carefully studied case the turbidite sequence has been uplifted, perched atop the diapir. The pattern of deformation on this outcropping diapir shows radial and concentric fractures which can be modeled by a vertical intrusion circular in plan view. Magnetic studies limit the possible composition to basalt or serpentinite. A 60-km-long median ridge is also likely to be the product of intrusion along the transform fault. The survey at site 2 pointed out the importance of vertical tectonics in the transform valley floor and in particular the importance of diapiric intrusions of either basaltic or serpentinite composition. Based on initial boundary conditions and present tectonic elements in the Tamayo fault zone, a possible history of the mouth of the Gulf of California is outlined. The median ridge was emplaced starting approximately 0.8 m.y. ago by regional extension across the transform fault, the result of ‘leaky’ transform faulting. The diapirs occur along a possible ‘relay’ zone of extension midway along the fault which began approximately 0.15 m.y. ago. The extension in this case is parallel to the trend of the transform fault, is still occurring at present, and may evolve into a true spreading center.
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  • 5
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: 2D NMR spectra have been measured at variable temperatures between -100°C and +110°C in a sample of melt crystallized deuterated polyethylene (PE). The line shape could be decomposed into a central part originating from deuterons in the amorphous regions and outer parts from crystalline regions of PE. The “NMR crystallinity” determined from this separation was 72% in agreement with the X-ray crystallinity of 74%. Changes of the crystalline NMR line shape were interperted in terms of oscillations around the chain axis, the r.m.s. oscillation amplitude varying from 5° at 40°C to 12° at 110°C. The central part of the NMR line shape indicates the existence of a “narrow” and a “medium” component due to different motional processes in the amorphous regions.
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  • 6
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Thermal Behaviour of Sulfates. II. On the Thermal Dehydration of ZnSO4 · 7 H2O and the Effect of High Temperature upon Anhydrous ZnSO4The dehydration of ZnSO4 · 7 H2O and effect of high temperature upon unhydrous ZnSO4 was examined by means of continous high temperature Guinier photographs. On heating in air ZnSO4 · 7 H2O decomposes stepwise to ZnSO4 · 6 H2O, to an unknown hydrate, to the monohydrate and finally to N—ZnSO4, which is the thermodynamically stable modification at S.T.P. At about 700°C a reversible transformation to H-ZnSO4 can be observed which can start from N—ZnSO4 or H-ZnSO4, proceeds to the oxide sulfate Zn3O(SO4)2 and finally to ZnO.ZnSO4 · 6 H2O crystallizes monoclinically in the hexahydrite structure with a25°C = 9.981 Å, b25°C = 7.250 Å, c25°C = 24.280 Å, β25°C = 98.45°, Z = 8, space group: C 2/c. Cubic H-ZnSO4 is the first A2+B6+O4 compound of H-Cristobalit structure; probable space group F 43 m with a700°C = 7.18 Å, Z =4, N-Zn3O(SO4)2 is monoclinic probable space group B 2 with a25°c=13.987 Å, b25°c=6.706 Å, c25°c =7.379 Å β25°c=90.69°, Z=4, Above 420°C N-Zn3(SO4)2 becomes orthorhombic where at first of all H′-Zn3O(SO4)2 which has a reversible transformation point to H-Zn3O(SO4)2 at 655°C is formed. The probable space group of H-Zn2O(SO4)2 is C 2221 with a 850°C = 7.36 Å, b350°C = 13.96 Å, c850°C = 6.79 Å Z = 4, The solid solution N—Cu1,5Zn1,5O(SO4)2 is isotypic with N—Zn3O(SO4)2 and has the lattice constants a25°C = 14.03 Å, b25°C = 6.62 Å, c25°C = 7.33 Å, β25°C = 90.58°, Transoformations into the non quenchable high temperature modifications H-ZnSO4, H′-Zn3O(SO4)2 and H-Zn3O(SO4)2 are displacive. The thermal expansion of N-ZnSO4 and H-ZnSO4 and H-ZnSO4 has been exa-mined.
    Notes: Mit kontinuierlichen Heizguinieraufnahmen wurde die Dehydratisierung von ZnSO4 · 7 H2O und das Hochtemperaturverhalten von wasserfreiem ZnSO4 untersucht. Der Abbau von ZnSO4 · 7 H2O verläuft an der Luft über das 6-Hydrat, eine unbekannte Hydratphase und das 1-Hydrat zum N-ZnSO4, der Normaltemperaturform; bei etwa 700°C wird die reversible Umwandlung in H-ZnSO4 beobachtet. Die Thermolyse, die von N-ZnSO4 oder H-ZnSO4 ausgehen kann, verläuft über das Oxidsulfat Zn3O(SO4)2 weiter zum ZnO.ZnSO4 · 6 H2O kristallisiert monoklin im Hexahydrit (MgSO4 · 6 H2O)-Typ mit a25°C = 9,981 Å b25°c = 7,250 Å, c25°C = 24,280 Å, β25°C = 98,45°, Z = 8, RG: C 2/c. Das kubische H-ZnSO4 ist die erste A2+B6+O4-Verbindung mit H-Cristobalit-Struktur; wahrscheinliche RG: F 43 m mit a700°C = 7,18 Å, Z = 4. N—Zn3O(SO4)2 ist monoklin mit der wahrscheinlichen RG: B 2 mit a25°C = 13,987 Å b25°C = 6,706 Å, c25°C = 7,379 Å, β25°C = 90,69°, Z = 4. Oberhalb 420°C wird das Oxidsulfat orthorhombisch, wobei zunächst H′-Zn3O(SO4)2 entsteht, das bei 655°C reversibel in H-Zn3O(SO4) übergeht. Für H-Zn2O(SO4)2 ist die wahrscheinliche RG: C 2221 mit a850°C = 7,36 Å, b 850°C = 13,96 Å, c850°C = 6,79 Å, Z = 4. Der Mischkristall N—Cu1,5 Zn1,5O(SO4)2 ist isotyp mit N-Zn3O(SO4)2 und besitzt die Gitterkonstanten a25°C = 14,03 Å, b25°C = 6,62 Å, c25°C = 7,33 Å, β25°C = 90,58°, Z = 4. Die Umwandlungen in die nicht abschreckbaren Hochtemperaturformen (H-ZnSO4 H'-Zn3O(SO1)2 und H-Zn3O(SO4)2) erfolgen displaziv. Die thermische Dilatation von N-ZnSO4 und H-ZnSO4 wurde ermittelt.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Computing 17 (1976), S. 23-36 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Abstract This papers gives a survey of possible speed-ups of matrix-multiplication by the methods due to S. Winograd and V. Straßen. Questions of implementation of the algorithms are investigated and formulas for the required additional core-memory are given. By using a machine model which is similar to existing computers the results given are of practical importance.
    Notes: Zusammenfassung Diese Arbeit soll eine Übersicht über den möglichen Zeitgewinn geben, der durch den Einsatz der schnelleren Matrix-Multiplikationen von S. Winograd und V. Straßen erzielbar ist. Implementierungsfragen werden besprochen und der benötigte Zusatzspeicher wird ermittelt. Die Abschätzungen beruhen auf einem Rechner-Modell, welches den heutigen Rechenanlagen nachgebildet ist, und liefern daher realistische Ergebnisse.
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  • 8
    ISSN: 1432-1076
    Keywords: Partial trisomy 10p ; Malformation-retardation-syndrome ; Inheritance ; Reciprocal translocation, balanced/unbalanced ; Maternal carrier
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Es wird von einer Familie berichtet, in der durch mütterliche balancierte Translokation t(5;10)(p15;p13) eine unbalancierte Chromosomenkonstitution bei zwei Kindern entstand. Mit Hilfe der G-Bandenanalyse wurde sie als Trisomie des distalen Abschnitts des kurzen Armes von Chromosom 10 (p13→pter) identifiziert. Der Vergleich mit 15 Literaturberichten von Trisomie 10p bestätigt das Vorliegen eines charakteristischen Dysmorphiesyndroms.
    Notes: Abstract This is the report of a family in which a balanced translocation in the mother t(5;10)(p15;p13) led to an unbalanced chromosomal constitution in two children. It was identified by G-banding analysis as trisomy of the distal portion of the short arm of chromosome 10 (p13→pter). Comparison with 15 previous reports of trisomy 10p confirms the existence of a characteristic dysmorphic syndrome.
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    European journal of pediatrics 132 (1979), S. 271-276 
    ISSN: 1432-1076
    Keywords: Exostoses ; Benign osteochondromas ; Bone tumors ; Radiation therapy ; Radium-224 ; Thorium X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Exostoses are benign cartilaginous tumors of bone. They can occur naturally or be induced by radiation therapy during the time of skeletal growth. We have observed exostoses in 28 of 218 children given repeated injections of radioactive bone-seeking 224Ra. The younger the age at irradiation, the higher the incidence of exostoses. Boys are more susceptible than girls. To our knowledge, none of these radiation-induced exostoses have become malignant, although 36 of these children have developed bone sarcomas elsewhere in the skeleton.
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  • 10
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Stability in aqueous solution of some complexes of heavy metals with diaza-polyoxamacrocyclic ligandsStability of metal complexes (Mn+ = Cu2+, Ni2+, Co2+, Zn2+, Pb2+, Ag+ and Cd2+) with five diaza-polyoxamacrocycles (L = [2.1.1], [2.2.1], [2.2.2], [2.1] and [2.2] ) have been determined at 25°, in 0.1 M Et4N+ClO4- aqueous solutions, by means of potentiometric titrations. All cations form MLn+ complexes; Cu2+ also forms the MHL(n+1)+ protonated species with both [2.2.1] and [2.1.1] ligands. The stability of these complexes has been discussed in terms of structure and by considering the ionic radii of the cations together with the radii of the macrocyclic cavities. Different behaviour is observed between some of these complexes and the well known alkali and alkaline-earth cryptates, partly due to the more covalent nature of bonds formed by the investigated cations and the donor sites of the ligands. The effect of the substitution of two oxygen by two sulfur atoms in the pentadentate ligand [2.1] on the stability of the complexes is reported.
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