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排序方式: 共有4046条查询结果,搜索用时 15 毫秒
71.
This retrospective analysis was conducted between May 1997 and May 2000 at the Centro de Atención Nutricional Infantil de Antímano, CANIA, in Caracas, Venezuela to assess the efficacy of two treatments (ambulatory versus day-care) of mild and moderate malnourished children. Inclusion criteria were: children under 10 years old with mild and moderate malnourishment, who attended a minimum of 3 control visits during a period of 12 months. One hundred fourteen malnourished children were included: fifty seven in ambulatory treatment and fifty seven in day-care treatment paired per nutritional diagnosis, gender and age (thirty nine mild and eighteen moderate malnourished children). The nutritional recovery criterion was weight for height above tenth percentile. No relation was found between treatment approaches and nutritional recovery at 3 and 6 months of treatment. In the group of mild malnourished children, the percentage of recovered patients at 3 months of treatment, that kept their recovered condition at 6 months was 83% (15/18) in the ambulatory treatment and 82% (18/22) in the day-care treatment Age of children, associated disease, acute morbidity, dietetic risk and mother's education and age were not associated with nutritional recovery at 6 months of treatment (p > 0.05). The day-care approach resulted as effective as ambulatory in mild malnourished children. In moderate malnourished new studies will need to be conducted with greater number of patients. 相似文献
72.
Three formulations of mix concentrated milk with hydrosolubles extract of soybean powder and cow's milk were prepared. The products were condensed up to 31% and 33.65% of solids in a vacuum evaporator at temperature of 45 degrees and 58 degrees C with a vacuum pressure of 540 mmHg. The products obtained were compared with standard concentrated milk through sensory evaluation showing satisfactory characteristics. 相似文献
73.
Boundary scan test,test methodology,and fault modeling 总被引:1,自引:0,他引:1
The test technique called boundary scan test (BST) offers new opportunities in testing but confronts users with new problems too. The implementation of BST in a chip has become an IEEE standard and users on board level are the next group to begin thinking about using the new possibilities. This article addresses some of the questions about changes in board-level testing and fault diagnosis. The fault model itself is also affected by using BST. Trivial items are extended with more sophisticated details in order to complete the fault model. Finally, BST appears to be a test technique that offers a high degree of detectability on board level, but for diagnosis, some additional effort has to be made. 相似文献
74.
Lucas F. de Lima Cristiane C. Maciel André L. Ferreira Rafael J. G. Rubira Carlos J. L. Constantino Marystela Ferreira 《应用聚合物科学杂志》2021,138(5):49750
In this paper, we report the controlled fabrication of layer-by-layer (LbL) films deposited on gold substrates with three different supramolecular architectures using polypyrrole (Ppy) and magnetite nanoparticles (Fe3O4-np), besides conventional poly(allylamine hydrochloride) (PAH) e poly(vinyl sulfonic acid) (PVS) polyelectrolytes, demonstrating the synergistic effect between Ppy and Fe3O4-np such as a result of their interaction. Modified gold electrodes were analyzed by contact angle (wettability), surface plasmon resonance (SPR), raman spectroscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. The (Fe3O4-np/Ppy)3 architecture was also evaluated by scanning electron microscopy. The modified gold electrodes present more homogeneous covering, higher electron transfer and a decrease of resistance with the incorporation of the nanostructured materials such as Ppy and Fe3O4-np forming (Fe3O4-np/Ppy)3 LbL film. The results carried out in this study suggest that the (Fe3O4-np/Ppy)3 LbL film can be applied as a possible electrochemical or optical non-enzymatic sensor for analytical detection. 相似文献
75.
Polymer/carbon nanotube nanocomposites have attracted high interest for a wide spectrum of applications, including antistatic packaging used to protect electronic devices against electrostatic discharge. Polytrimethylene terephthalate (PTT)/maleic-anhydride-grafted PTT (PTT-g-MA)/acrylonitrile butadiene styrene (ABS) blend-based multiwall carbon nanotubes (MWCNTs) nanocomposites were prepared through extrusion. It was conducted chemical functionalization on the MWCNTs by oxidation using nitric acid to introduce functional groups. The effect of the amount (0.5 or 1.0 wt%) and functionalization of MWCNTs on the nanocomposites was investigated. Despite the poor barrier properties of PTT/PTT-g-MA/ABS/MWCNT nanocomposites due to the presence of voids confirmed by scanning electron microscopy (SEM), the nanocomposites with functionalized MWCNT (MWCNTf) showed excellent barrier properties, indicating that the functionalization process improved the interaction between the MWCNTs and the matrix. The addition of MWCNTs into PTT/PTT-g-MA/ABS blend decreased the electrical resistivity by eight orders of magnitude. The use of MWCNTf may still disrupt the electrical network pathway and slightly decreasing the electrical resistivity, but the nanocomposites present the desired properties required for antistatic packaging. 相似文献
76.
Anna Raffaela de Matos Costa Juliana Cysneiros Lima Raquel dos Santos Lhaira Souza Barreto Mariana Alves Henrique Laura Hecker de Carvalho Yêda Medeiros Bastos de Almeida 《应用聚合物科学杂志》2021,138(36):50916
This work deals with the rheological, morphological, and thermal properties of composites having poly(ethylene terephthalate) (PET), polyamide-6 (PA6), and their blends as matrices, and rice husk ash (RHA) as a filler. The study determines the effect of composition on the change in viscosity and rate of degradation during processing in a torque rheometer. Our data indicates that thermal stability and degradation during processing depend on matrix composition and filler concentration. SEM micrographs show both partial adhesion of the filler to the matrices and filler pullout. Optical microscopy shows particle agglomeration and that agglomerate size increased with filler content. FTIR investigates the shifting of absorption bands of PET/PA6 composite after the addition of RHA and attributes the selective dispersion of RHA to the formation of hydrogen bonds. Our data supports the idea that filler employed here is an option to develop polymer composites with improved properties. 相似文献
77.
Electrochemical tests were carried out on steel/steel multi-laminar cells under thin layers of sulphate solution simulating atmospheres with contents of 20, 50 and 75 μg m−3 of SO2 and a relative humidity of 85%. Measurements of the current flowing between the two electrodes of the cell vs drying time and impedance measurements for different times were taken. Potentiodynamic cathodic polarization plots were also obtained for one concentration of contaminant at various drying times using three electrode multi-laminar cells. The results showed that the multi-laminar cells allowed the drying process of the thin electrolyte films to be followed. The use of electrochemical techniques gave information on the kinetics and mechanism of the corrosion process occurring during the drying period. Initially the process is controlled by oxygen diffusion through the liquid film, but for longer periods the control changes to the anodic reaction. 相似文献
78.
Francisco Henrique Ferreira Ana Paula C. da Silva Alex B. Vieira 《Peer-to-Peer Networking and Applications》2016,9(1):1-15
Despite the large number of works devoted to understand P2P live streaming applications, most of them put forth so far rely on characterizing the static view of these systems. In this work, we characterize the SopCast, one of the most important P2P live streaming applications. We focus on its dynamics behavior as well as on the community formation phenomena. Our results show that SopCast presents a low overlay topology diameter and low end-to-end shortest path. In fact, diameter is smaller than 6 hops in almost 90 % of the observation time. More than 96 % of peers’ end-to-end connections present only 3 hops. These values combined may lead to low latencies and a fast streaming diffusion. Second, we show that communities in SopCast are well defined by the streaming data exchange process. Moreover, the SopCast protocol does not group peers according to their Autonomous System. In fact, the probability that a community contains 50 % of its members belonging to the same AS (when we observe the largest AS of our experiments) is lower then 10 %. Peers exchange more data with partners belonging to the same community instead of peers inside the same AS. For the largest AS we have, less than 18 % of peer traffic has been exchanged with another AS partners. Finally, our analysis provides important information to support the future design of more efficient P2P live streaming systems and new protocols that exploit communities’ relationships. 相似文献
79.
Mariana G. Figueiro Brittany Wood Barbara Plitnick Mark S. Rea 《Journal of the Society for Information Display》2013,21(10):417-421
Self‐luminous electronic devices emit optical radiation at short wavelengths, close to the peak sensitivity of melatonin suppression. The present paper investigated if light from a 178‐cm (70 in.) television suppressed melatonin. Results showed that light from televisions does not impact melatonin levels in the evening. 相似文献
80.
Mariana Pinteala Valeria Harabagiu Cornelia Cotzur Marian N. Holerca Bogdan C. Simionescu 《Polymer Bulletin》1994,32(2):173-178
Summary Carboxyester- and carboxyamido-terminated polydimethylsiloxanes were obtained through the reaction of cyclic anhydrides (succinic, maleic and phthalic anhydride) with hydroxypropyl- and aminoalkyl-terminated polydimethylsiloxanes, respectively. The reactivity of the starting compounds and the influence of the reaction conditions on the characteristics of the final products are discussed.Part 1: Eur. Polym. J., in press 相似文献