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Presents an obituary for Elizabeth Douvan (1926-2002). Douvan was a pioneer in the study of changing gender, work, and family roles; personal values; and well-being in the second half of the 20th century. Through her research, she contributed to the interdisciplinary fields of social psychology and women's studies while building and strengthening institutions that remain committed to the same mission. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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PMMA, poly(metheylmethacrylate), nanocomposites were made by in situ radical polymerization of MMA, methylmethacrylate, with colloidal silica (ca. 12 nm) to study the effects of nanoscale silica particles on the physical properties and flammability properties of PMMA. Transparent samples resulted and the dispersity of the particles was examined by transmission electron microscopy and atomic force microscopy. The addition of nanosilica particles (13% by mass) did not significantly change the thermal stability, but it made a small improvement in modulus, and it reduced the peak heat release rate roughly 50%. Last, the flame‐retardant mechanism provided by the addition of nanosilica particles in PMMA is discussed. Published 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2072–2078, 2003  相似文献   
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The purpose of this work was to study the role of cesium in sodium‐based geopolymer and its thermal stability for nuclear waste management. A series of mixed sodium and cesium geopolymer samples (Na1?x Cs x )2O·Al2O3·SiO2·12H2O (referred to as (Na1? x Cs x )‐GP, where x = 0, 0.08, 0.15, 0.42, 1) have been prepared. All geopolymer samples were heated at 1100°C for 24 h. Pollucite (CsAlSi2O6) and feldspathoid (CsAlSiO4) were crystallized from Cs‐GP. Nepheline (NaAlSiO4) and a small amount of crystallized silica were obtained from Na‐GP. The other geopolymers (Na1? x Cs x )‐GP (x = 0.08, 0.15, 0.42) led to pollucite and nepheline main phases. Amorphous silica phase was observed in all the geopolymer samples with various amounts. Phase quantification and scanning electron microscope revealed that higher Cs concentrations in Na‐GP tend to decrease the amorphous phase while improving pollucite and nepheline phase quantification. The amorphous geopolymers have also been studied by pair distribution function analysis. Tetrahedral chains formed by T–O bonding (with T = Si, Al) were shown to be more tighten around Cs+ than around Na+. It led to shorter Cs–T bond than Na–T bond matching the higher solvation property of Na+. Furthermore, thermal study analysis pointed out the fact that geopolymer samples (Na1? x Cs x )‐GP, can be considered as solid solutions.  相似文献   
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Sugar content is one of the most important quality attributes of citrus fruit, either for fresh or for processing market. Since sugars in citrus juice are highly correlated with total soluble solids (TSS) content, which can be determined easily even by the means of a hand refractometer, TSS is one of the most frequently used quality index. Since TSS can be measured only destructively, the results are representative only if carried out on large samples and do not allow classifying marketable fruit one by one according to their specific sugar content. Objective of this experiment was to assess possibility and limits of a non-destructive estimation of citrus fruits internal quality parameters (TSS and titratable acidity) presenting thick peel by the use of a spectrophotometric portable VIS-NIR system. Four hundred fruit of “Miho” satsuma and 150 fruit of “Page” tangelo were used. Each fruit was first subjected to spectrophotometric acquisition and soon after was juiced and TSS and titratable acidity (TA) determined. Partial least squares (PLS) regression analysis was applied for constructing a predictive model based on the spectral normalized response, constructing the model on a sub-sample and verifying the model (prediction test) on independent ones. The TA relative to Page mandarin was predicted in the test with an r = 0.88 and a standard error of prevision (SEP) coefficient of variability of 3.8% while the TSS scored an r = 0.85 and a SEP coefficient of variability equal to 4%. The TA of Miho mandarin was predicted in the test with an r = 0.81 and a SEP coefficient of Variability of 8.3% while the TSS scored an r = 0.84 and a SEP coefficient of variability equal to 5.6%.  相似文献   
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The actual Italian production of clams is chiefly sustained by the native Tapes decussatus and the fortuitously imported Tapes philippinarum. Both species are commercialized as “Vongola verace”, but the commercial value of T. philippinarum is lower. The discrimination of species by sight is usually difficult and it cannot be done by observation based on shell morphology but only when animals open their valves hence displaying the two siphons. In this study, we propose a new, noninvasive method to discriminate individuals of both species based on the analysis of the external shape of their shells. Accordingly, in sympatric populations at two sites of the Po river outlet, we have chosen individuals (63 for T. decussatus and 57 for T. philippinarum) of comparable commercial size for which a certain genetic discrimination was previously done. Pictures of the left side valve were taken for all specimens. Their profiles were analyzed with the elliptic Fourier analysis. The mean outline for each species was graphically extracted. The coefficients of the harmonic equations were analyzed by multivariate classification (partial least squares discriminant analysis [PLSDA]). Results showed a high percentage of correct classification of individuals of both species (96.6%). Contour analysis reflected the overall shell shape and thus identified morphological aspects that were difficult to recognize and quantify in sight. The high percentage of correct classifications obtained by combining the analysis of elliptic Fourier harmonics with PLSDA demonstrated the feasibility of this method to discriminate species with a high level of resemblance.  相似文献   
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The catalytic activity of Ni–Rh on the synthesized BEA zeolite in carbon dioxide reforming of methane has been investigated. Catalysts were prepared using the incipient wetness impregnation method, with a total content of metals up to 5 wt%. Catalysts were characterized through XRD, TPR, N2 adsorption, SEM, AAS, TG/DSC analyses. The prepared Ni–Rh zeolites were tested for their catalytic activity at 700 °C, at atmospheric pressure, and at CH4/CO2 ratio of 1. Catalytic results showed that bimetallic based zeolites exhibit high activity (CH4 and CO2 conversion equal to 73 and 78, respectively) but monometallic Rh catalysts were the only one stable against coke formation.  相似文献   
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The marital relationship rarely exists in isolation and yet few studies have examined the multiple relationships experienced by most married people. This study used the Convoy Model of Social Relations to examine patterns of multiple relationships and well-being among men and women ages 22 to 79 years (N = 654). Cluster analyses identified profiles of relationship quality among people with spouse, family (children, mother, father), and a best friend (N = 451) and those married with family but no best friend (N = 202). Relationship profiles differed in quality and by gender, race, and age. Among people with best friends, having at least 2 high quality relations, not necessarily with a spouse, is associated with greater well-being. In contrast, among people without best friends, the spousal relation appears to be particularly important for well-being. Although family relationships (e.g., spouse) are important for well-being, interventions should consider the composition and quality of social networks to determine which relationships may need improvement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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