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101.
Lawrence E. Matson Helmut Erhart Moonyong Lee Robert A. Rapp 《Metallurgical and Materials Transactions A》1984,15(12):2241-2246
In situ oxidation of polycrystalline iron at 1200 °C and
atm has revealed symmetrical square growth pits in the wustite scale. The pit walls are nominally oriented with the {110}
planes of the wustite lattice but are dissociated into macro- and microledges consisting of {100}-type planes. Such growth
pits intrude into the wustite scale at the gas/oxide interface, and at the oxide/metal interface small oxide nodules intrude
into the metal. After sufficiently long oxidation times at 1200 °C, rate control should shift from oxidant arrival to cation
volume diffusion, and pits are then destabilized and a planar morphology is achieved. 相似文献
102.
Double contrast examination constitutes an important element in radiological gastric examination. The author examines the history of the term "double contrast" and defines the designation of "double contrast examination". The exclusive use of the double contrast method reduces the diagnostic value of gastric X-ray examinations. Thus a method is suggested that will avoid the disadvantages of exclusive double contrast examination while adequately including double contrast in the gastric examination. This is done by using various methods - according to the problem posed - in order to achieve the double contrast. 相似文献
103.
104.
HJ Suschke 《Canadian Metallurgical Quarterly》1976,94(16):977-980
A multicentric open clinical trial was carried out by 8 practising specialists in dermatology or paediatrics in patients with bacterial skin diseases who were subjected to a systemic therapy with Syncillin (=Azidocillin). The Syncillin presentation for adults and schoolchildren was tablets of 750 mg each, and sachets of 125 mg or 250 mg for infants. The duration of treatment was 10 days. The parameters analyzed were bacteriological findings and the clinical course of disease. 71 (=74%) of the 96 patients included in this study were considered as cured, 21 (=22%) as improved and 4 patients (=4%) as unchanged. Bacterial identification was still positive in 10 cases after the termination of treatment. However, this did not preclude the assessments of "cured' (3 cases) or "improved' (7 cases). The tolerance of the preparation was considered as "very good' or "good' in 91 and as "poor' in 5 patients. The most common side effects were nausea and diarrhoea. Exanthema was observed in 2 cases. None of these side effects, however, made a discontinuation of medication necessary. The era of rational and well-directed chemotherapy enables good therapeutic approach also to bacterial skin diseases. 相似文献
105.
Amon Rapp Alessandro Marcengo Luca Buriano Giancarlo Ruffo Mirko Lai Federica Cena 《Behaviour & Information Technology》2018,37(4):335-366
Thanks to the advancements in ubiquitous and wearable technologies, Personal Informatics (PI) systems can now reach a larger audience of users. However, it is not still clear whether this kind of tool can fit the needs of their daily lives. Our research aims at identifying specific barriers that may prevent the widespread adoption of PI and finding solutions to overcome them. We requested users without competence in self-tracking to use different PI instruments during their daily practices, identifying five user requirements by which to design novel PI tools. On such requirements, we developed a new system that can stimulate the use of these technologies, by enhancing the perceived benefits of collecting personal data. Then, we explored how naïve and experienced users differently explore their personal data in our system through a user trial. Results showed that the system was successful at helping individuals manage and interpret their own data, validated the usefulness of the requirements found and inspired three further design opportunities that could orient the design of future PI systems. 相似文献
106.
HJ 《家用电脑与游戏机》2012,(11):46-47
大家在筛选录像的时候会发现,每一场DOTA2比赛都有自己的等级,分为普通、高、非常高三种。比赛的等级是由每个人的Matchmarkingranking数值所决定的,我们简称其为MMR值,与天梯积分有点像。 相似文献
107.
Stefania Mamberti Maruthi K. Pabba Alexander Rapp M. Cristina Cardoso Michael Scholz 《International journal of molecular sciences》2022,23(7)
CTCF is a nuclear protein initially discovered for its role in enhancer-promoter insulation. It has been shown to play a role in genome architecture and in fact, its DNA binding sites are enriched at the borders of chromatin domains. Recently, we showed that depletion of CTCF impairs the DNA damage response to ionizing radiation. To investigate the relationship between chromatin domains and DNA damage repair, we present here clonogenic survival assays in different cell lines upon CTCF knockdown and ionizing irradiation. The application of a wide range of ionizing irradiation doses (0–10 Gy) allowed us to investigate the survival response through a biophysical model that accounts for the double-strand breaks’ probability distribution onto chromatin domains. We demonstrate that the radiosensitivity of different cell lines is increased upon lowering the amount of the architectural protein. Our model shows that the deficiency in the DNA repair ability is related to the changes in the size of chromatin domains that occur when different amounts of CTCF are present in the nucleus. 相似文献
108.
Thornell G Rapp H Hjort K 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2000,47(1):8-15
With the recently developed ion track lithography based on the selective etching, widening, and merging of ion-induced defects collectively resembling a superimposed anisotropy in certain areas as defined by a stencil mask, 39-kHz x-cut miniature tuning forks with a tine size of 331x2, 500x42 mum and a Q-value of up to 42 000 were fabricated from single crystalline quartz mostly to demonstrate this new technique's ability to structure difficult cuts, but also to benefit from the much simpler electrode configuration possible with this cut in comparison with ordinary z-cut watch tuning forks. 相似文献
109.
The flow field dynamics in open and packed segments of capillary columns has been studied by a direct motion encoding of the fluid molecules using pulsed magnetic field gradient nuclear magnetic resonance. This noninvasive method operates within a time window that allows a quantitative discrimination of electroosmotic against pressure-driven flow behavior. The inherent axial fluid flow field dispersion and characteristic length scales of either transport mode are addressed, and the results demonstrate a significant performance advantage of an electrokinetically driven mobile phase in both open-tubular and packed-bed geometries. In contrast to the parabolic velocity profile and its impact on axial dispersion characterizing laminar flow through an open cylindrical capillary, a pluglike velocity distribution of the electroosmotic flow field is revealed in capillary electrophoresis. Here, the variance of the radially averaged, axial displacement probability distributions is quantitatively explained by longitudinal molecular diffusion at the actual buffer temperature, while for Poiseuille flow, the preasymptotic regime to Taylor-Aris dispersion can be shown. Compared to creeping laminar flow through a packed bed, the increased efficiency observed in capillary electrochromatography is related to the superior characteristics of the electroosmotic flow profile over any length scale in the interstitial pore space and to the origin, spatial dimension, and hydrodynamics of the stagnant fluid on the support particles' external surface. Using the Knox equation to analyze the axial plate height data, an eddy dispersion term smaller by a factor of almost 2.5 than in capillary high-performance liquid chromatography is revealed for the electroosmotic flow field in the same column. 相似文献
110.
Up to now, the value of the dynamic critical exponent z is still an open question. We have studied this exponent in the intermediate (XY) critical regime in zero field for a set of high quality Bi
2
Sr
2
CaCu
2
O
8+
single crystals both by previously obtained critical exponents of the dc critical conductivity fluctuations [1] and in terms of Fisher-Fisher-Huse (FFH) dynamic scaling [2]. In this regime (i.e. the absence of Coulomb interactions), one would expect model-E dynamics (z = 1.5) to apply with the conserved charge-density conjugate to the phase fluctuations. However, we find the dynamic critical exponent to be z = 2, which is in agreement with the suggestion of FFH that due to the plasma fluctuation, fully relaxational dynamics, model A (z=2), should be appropriate. 相似文献