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A tertiary amine functionalized 4-nitro-4′-alkoxy azobenzene mesogen with a 10 or 12 carbon spacer (azo-nN) was synthesized and complexed in equimolar proportions with poly(acrylic acid) (PA-H) and poly(sulfonic acid) (PSS-H), and investigated by thermogravimetric analysis, differential scanning calorimetry, polarizing optical microscopy, Fourier transform infrared spectroscopy and X-ray diffraction. The neat azo-nN is characterized by a partial bilayer SA mesophase at higher temperatures, and a highly ordered phase, in which the molecules are stacked orthogonally in bilayers, at lower temperatures. As supported by infrared analysis, for the azo-nN/PA-H mixture, the complexation is partial while for the same azo-nN/PSS-H mixture, complete proton transfer occurs. When the azo-nN is blended with the PA-H, regarded as a weak acid, a biphasic system is generated and the thermotropic behavior of neat mesogen is not significantly affected. In contrast, by mixing the same mesogen with a PSS-H (regarded as a strong acid), the thermotropic behavior is significantly influenced: the complexation generated a partial or interdigitated smectic A or tilted smectic C lamellar phase. 相似文献
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Bonanno George A.; Moskowitz Judith Tedlie; Papa Anthony; Folkman Susan 《Canadian Metallurgical Quarterly》2005,88(5):827
Recent research has indicated that many people faced with highly aversive events suffer only minor, transient disruptions in functioning and retain a capacity for positive affect and experiences. This article reports 2 studies that replicate and extend these findings among bereaved parents, spouses, and caregivers of a chronically ill life partner using a range of self-report and objective measures of adjustment. Resilience was evidenced in half of each bereaved sample when compared with matched, nonbereaved counterparts and 36% of the caregiver sample in a more conservative, repeated-measures ipsative comparison. Resilient individuals were not distinguished by the quality of their relationship with spouse/partner or caregiver burden but were rated more positively and as better adjusted by close friends. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The performance of cemented carbide inserts coated with various PVD-films in milling Inconel 718 is evaluated by innovative analytical and experimental methods. Three PVD films with different micro and macro structures were applied. The coatings’ strength properties were detected by nanoindentations and by impact tests at various temperatures. These results were considered in FEM calculations of the material removal process to determine the mechanical and thermal loadings of the cutting wedge. Employing this innovative methodology, it is possible to capture proactively the effect of the cutting conditions on tool wear, thus reducing the effort dedicated in traditional sequential cutting experimentation. 相似文献
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A Tursi G Cammarota A Papa M Montalto G Veneto G Capelli L Cuoco G Branca G Fedeli G Gasbarrini 《Canadian Metallurgical Quarterly》1996,43(10):859-862
BACKGROUND/AIMS: Our study is to compare a short-term low-dose triple therapy with a long-term medium-dose double therapy for H.pylori eradication. MATERIALS AND METHODS: One hundred and ten consecutive patients, suffering from dyspeptic symptoms, with H.pylori infection, were randomly allocated to one of the following 2 groups with different therapeutic regimens: A) omeprazole 20 mg/day for 7 days, tinidazole 500 mg bid for 7 days, clarithromycin 250 mg bid for 7 days (55 pts, 20 with peptic ulcer); B) omeprazole 20 mg bid for 14 days, amoxycillin 1000 mg bid for 14 days (55 pts, 28 with peptic ulcer). The "H.pylori status" was evaluated by means of histology, culture and urease test, at entry and 8 weeks after treatment. RESULTS: Two group A and one group B pts didn't complete the treatment. The H.pylori eradication was obtained in 38 pts of group A (71.69%) (C.I.95%: 55.19176-80.86293), in 31 of group B (58.49%) (C.I.95%: 42.32777-69.7017); on Intention-to-Treat analysis, the rate of eradication gave similar results. Side effects occurred in 9 pts of group A (16.98%), in 8 of group B (14.81%). CONCLUSIONS: Short-term low-dose triple therapy with omeprazole/tinidazole/clarithromycin has a better cost/benefit ratio than long-term dual therapy with omeprazole/amoxycillin in the H.pylori eradication, but it causes more side-effects. 相似文献
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Alexander I. Iliev Michael S. Scordilis João P. Papa Alexandre X. Falcão 《Computer Speech and Language》2010,24(3):445-460
A new method for the recognition of spoken emotions is presented based on features of the glottal airflow signal. Its effectiveness is tested on the new optimum path classifier (OPF) as well as on six other previously established classification methods that included the Gaussian mixture model (GMM), support vector machine (SVM), artificial neural networks – multi layer perceptron (ANN-MLP), k-nearest neighbor rule (k-NN), Bayesian classifier (BC) and the C4.5 decision tree. The speech database used in this work was collected in an anechoic environment with ten speakers (5 M and 5 F) each speaking ten sentences in four different emotions: Happy, Angry, Sad, and Neutral. The glottal waveform was extracted from fluent speech via inverse filtering. The investigated features included the glottal symmetry and MFCC vectors of various lengths both for the glottal and the corresponding speech signal. Experimental results indicate that best performance is obtained for the glottal-only features with SVM and OPF generally providing the highest recognition rates, while for GMM or the combination of glottal and speech features performance was relatively inferior. For this text dependent, multi speaker task the top performing classifiers achieved perfect recognition rates for the case of 6th order glottal MFCCs. 相似文献
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Satellite-based estimates of groundwater storage variations in large drainage basins with extensive floodplains 总被引:2,自引:0,他引:2
Frédéric Frappart Fabrice Papa Andreas Güntner Joecila Santos da Silva Frédérique Seyler William B. Rossow Marie-Paule Bonnet 《Remote sensing of environment》2011,115(6):1588-1594
This study presents monthly estimates of groundwater anomalies in a large river basin dominated by extensive floodplains, the Negro River Basin, based on the synergistic analysis using multisatellite observations and hydrological models. For the period 2003-2004, changes in water stored in the aquifer is isolated from the total water storage measured by GRACE by removing contributions of both the surface reservoir, derived from satellite imagery and radar altimetry, and the root zone reservoir simulated by WGHM and LaD hydrological models. The groundwater anomalies show a realistic spatial pattern compared with the hydrogeological map of the basin, and similar temporal variations to local in situ groundwater observations and altimetry-derived level height measurements. Results highlight the potential of combining multiple satellite techniques with hydrological modeling to estimate the evolution of groundwater storage. 相似文献
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G. Giannetto G. León J. Papa R. Monque R. Galiasso Z. Gabelica 《Catalysis Letters》1993,22(4):381-386
Propane aromatization (530°C, 1 atm) was used as a reaction model to evaluate the effect of the calcination temperature on the catalytic properties of an as-synthesized [Ga1.3]-ZSM-5 zeolite obtained from alkali-free media and calcined at two different temperatures: 530°C (C-530) and 750°C (C-750). Results show that in spite of its lower acidity, C-750 is more active and selective toward aromatics than C-530. This is probably due to the fact that at higher temperature the decomposition of organic compounds used during the zeolite synthesis is accompanied by a partial degalliation of the zeolitic support leading to the production of a bifunctional xGa2O3 /H-[Gay-ZSM-5(2x+y=1.3)catalyst. 相似文献