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  • 1
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 101 (1994), S. 4668-4681 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Intermolecular and intramolecular energy flow and subsequent bond dissociation in collinear collisions I–C≡C–H+Ar and I–C≡C–C≡C–H+Ar have been studied by classical trajectory techniques over the collision energy range of 0 to 10 eV. When the molecule is initially in the ground state, the overall energy transfer in I–C≡C–H+Ar is very small, but in I–C≡C–C≡C–H+Ar it is large. The collisionally perturbed C–H bond stores a large amount of energy from translation for a brief period during the early stage of collision and transfers most of it to the inner region of the molecule, specifically to the low frequency C–I vibration. Thus the high-frequency vibration of the perturbed C–H bond during the collision plays a crucial role in determining the extent of intramolecular energy transfer and, in turn, C–I dissociation. But in nondissociative collisions, there is another series of the C–H vibration at the latter stage of collision, transferring energy back to translation. This study also considers collision-induced intramolecular energy flow in the molecule with an initially excited C–H bond. The relaxation of the low-lying C–H excitation is very slow on a nanosecond time scale. However, when the excitation is high, the vibrational frequency of the C–H bond is significantly weakened, thus becoming comparable to that of the triple bond, in which case the isolating effect of the adjacent C≡C bond is no longer important and intramolecular energy flow becomes efficient.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Inorganic chemistry 29 (1990), S. 3298-3301 
    ISSN: 1520-510X
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of fish biology 39 (1991), S. 0 
    ISSN: 1095-8649
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Oxygen uptake rates and yolk-inclusive dry weiGhts were measured during the egg and yolk-sac larval stages of milkfish, Chanos chanos (Forsskal). Oxygen uptake by eggs and yolk-sac larvae was measured to assess the effects of four salinities (20,25,30,35 ppt) at 28°C. The effects of three temperatures (23,28,33°C) on oxygen uptake by yolk-sac larvae were determined at a salinity of 35 ppt. Dry weights were measured throughout embryonic development at 28°C and the yolk-sac stage at 23.28 and 33°C.Oxygen uptake rates of eggs increased more than fivefold during embryogenesis (0.07±0.03 to 0.40 ± 03 μl O2 egg −1 h −1;blastula to prehatch stage). Larval oxygen uptake did not change with age but was affected by rearing temperature (0.33 ± 0.08, 0.44 ± 0.07 and 0.63 ± 0.13 μl O2 larva −1 h−1 at 23, 28 and 33°C, respectively; Q10= 1.93). Acute temperature changes from 28 to 33°C caused significant increases in oxygen uptake by embryos (Q 10= 1.69–3.58) and yolk-sac larvae (Q 10=2.55). Salinity did not affect metabolic rates.Dry weight of eggs incubated at 28°C decreased 13% from fertilization to hatching. Incubation temperatures from 23–33°C did not affect dry weights at hatching. Rearing temperatures significantly affected the rate of larval yolk absorption (Q 10= 2.25).
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Dental traumatology 7 (1991), S. 0 
    ISSN: 1600-0595
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract The purpose of this study was to evaluate apical extrusion of root canal content using ultrasonic and hand instrumentation. Forty-nine tooth models were fabricated with clear resin. Each model contained a canal in the center. Each tooth model was mounted in a plastic cube (1 × 1 × 2 cm) with white dental plaster so that the coronal 2–3 mm of the model was exposed for instrumentation. Methylene blue dye with glycerin was used as a marker for root canal content. The study consisted of three groups. In group I, Enac ultrasonic instrumentation was used 1 mm from the apex; in group II, Enac ultrasonic instrumentation was used 3 mm from the apex; in group III, K Files were used with a push-pull instrumentation technique, 1 mm from the apex. After instrumentation the resin models were extracted and the plaster blocks were sectioned through the long axis of the models. Photographs were made of the area of apical leakage and the amount of dye penetration was measured using a planimeter. There were no differences between hand instrumentation and both ultrasonic groups. At p〈0.05, ultrasonic instrumentation 3 mm from the apex leaked significantly more than the ultrasonic instrumentation 1 mm from the apex.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    International orthopaedics 17 (1993), S. 241-244 
    ISSN: 1432-5195
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Deux cent onze patients atteints de hernie discale lombaire, confirmée par imagerie par résonance magnétique (IRM) et représentant 242 niveaux, ont été répartis en cinq groupes. Le diagnostic IRM a été comparé aux constatations opératoires afin d'évaluer de façon prospective la précision diagnostique de la classification IRM. Il n'y a pas eu d'exploration discale négative. Pour la distinction entre protrusion et autres types de hernie discale, la sensibilité, la spécificité et l'exactitude de l'IRM ont été respectivement de 92%, 91% et 92%. Pour la séquestration discale, la sensibilité a été de 92%, la spécificité de 99% et l'exactitude de 97%. En ce qui concerne l'extrusion sous-ligamentaire, on a noté une sensibilité de 71%, une spécifité de 82% et une exactitude de 79%, tandis que pour les extrusions trans-ligamentaires la sensibilité a été de 52%, la spécifité de 92% et l'exactitude de 79%. L'exactitude moyenne pour la prévision du type de hernie discale a donc été de 85%. L'IRM de haute résolution est donc très efficace pour la détection des lésions discales et leur classification.
    Notes: Summary Two hundred and eleven patients with lumbar disc herniation at 242 levels were divided into 5 groups by their appearances on magnetic resonance imaging (MRI), and the findings at operation were compared to assess the accuracy of the MRI classification. There were no negative explorations. There was 92% sensitivity, 91% specificity and 92% accuracy for MRI in distinguishing protruded discs from other forms of lumbar disc herniation. For sequestrated discs there was 92% sensitivity, 99% specificity and 97% accuracy. In the extruded subligamentous type there was 71% sensitivity, 82% specificity and 79% accuracy, and 52% sensitivity, 92% specificity and 81% accuracy in the extruded transligamentous type. The overall accuracy of MRI predicting the types of herniated lumbar intervertebral disc was 85%. High resolution MRI is sensitive in detecting disc disease and specific in characterizing various subgroups of disc herniation, especially those which are sequestrated.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Copenhagen : International Union of Crystallography (IUCr)
    Acta crystallographica 49 (1993), S. 806-811 
    ISSN: 1600-5740
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Polymer bulletin 29 (1992), S. 521-525 
    ISSN: 1436-2449
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary The miscibility of poly(4-vinyl pyridine) (P4Py) with polysulfone (PSf) and four carboxylated polysulfone samples (CPSf) was studied by differential scanning calorimetry. P4Py is immiscible with PSf but is miscible with CPSf having degrees of carboxylation of 0.43, 0.93, 1.38 and 1.93. In some cases, P4Py and CPSf form complexes with varying stoichiometries. A high degree of carboxylation of CPSf and a high CPSf content in the feed favor complexation.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Circuits, systems and signal processing 9 (1990), S. 421-433 
    ISSN: 1531-5878
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Abstract The paper first briefly reviews some subspace techniques for high-resolution array processing. It is shown that existing high-resolution techniques like the MUSIC algorithm are based on visual inspection of the spatial spectrum. It is not a scientifically valid means of assessing resolution of a spectrum estimator. The paper then proposes a technique based on a combination of optimal processing and signal subspace extraction for high-resolution array processing. Numerical results show that the proposed technique not only achieves superresolution of the spectrum, but also provides power estimates of the arrivals.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 1434-601X
    Keywords: 23.20.Lv ; 27.60+j
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract High spin states in115Te have been studied using the89Y (29Si, p2n) reaction at a beam energy of 108 MeV.γ-γ coincidence, Eγ, Iγ and excitation functions have been measured. The level scheme has been extended to 82 MeV excitation energy relative to the 11/2 state and several new states are established. The systematical behaviour in odd- N Te isotopes is discussed.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 1434-601X
    Keywords: 23.20.Lv ; 27.70.+q
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract 154Ho was studied via141Pr(16O,3n) reaction at beam energy of 75 MeV. We found two new rotationally aligned bands made of neutron h9/2 and f7/2 orbitals coupled to a proton h11/2 orbital. As with several new high-spin states, up to I=20, the ground state band with odd parity starts to show anomalous signature splitting at I=13 in this doubly odd154Ho. The observed rotational bands in154Ho are quite consistent with the onset of collectivity which appears in general at neutron number of 87 in neutron-deficient rare-earth nuclei.
    Type of Medium: Electronic Resource
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