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This study investigated developmental trends associated with the Deese/Roediger-McDermott false-memory effect, the role of distinctive information in false-memory formation, and participants' subjective experience of true and false memories. Children (5- and 7-year-olds) and adults studied lists of semantically associated words. Half of the participants studied words alone, and half studied words accompanied by pictures. There were significant age differences in recall (5-year-olds evinced more false memories than did adults) but not in recognition of critical lures. Distinctive information reduced false memory for all age groups. Younger children provided with distinctive information, and older children and adults regardless of whether they viewed distinctive information, expressed higher levels of confidence in true than in false memories. Source attributions did not significantly differ between true and false memories. Implications for theories of false memory and memory development are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
995.
The conversion of monochloropropanes and dichloropropanes over acid catalysts has been investigated in the presence of oxygen. In the temperature range of 450–550 K, dehydrochlorination of monochloropropanes to propene and HCl occurs selectively over silica–alumina, while significant formation of chlorinated by-products is observed over ZSM5 zeolite catalyst even at higher temperatures. Dichloropropanes conversion over silica–alumina catalyst gives rise mainly to chloropropenes in the temperature range 500–700 K. COx are predominant products only at the highest reaction temperatures (just above 700 K). Water vapor in the feed only slightly affects conversions and selectivities. Deactivation processes occur upon dichloropropane conversion, mainly due to coke deposition.

The conversion of highly chlorinated compounds, such as trichloroethylene (TCE) has been tested over silica–alumina and over HY zeolite in the presence of water vapor in the so-called “steam reforming” conditions (HVOC:water=1:2). With diluted feed (1200 ppm) on HY, reaction occurs above 800 K and formation of chlorinated by-products is minimized, COx being the main reaction products. At higher HVOC concentrations conversion is obtained at even lower temperature (600 K), but no more negligible by-products formation has been detected. In our conditions zeolite catalyst is more effective in TCE total conversion than silica–alumina.  相似文献   

996.
Edible oil extraction with petroleum derivatives as solvents has caused safety, health, and environmental concerns everywhere. Thus, finding a safe alternative solvent will have a strong and positive impact on environments and general health of the world population, considering the scale of oil extraction operations worldwide. The extraction of oil from rice bran by d‐limonene and hexane (for comparison) has been carried out at their respective boiling points at various solvent‐to‐meal ratios and for various extraction times. The preliminary data suggested that the optimum solvent‐to‐meal ratio and extraction time required for d‐limonene extraction of rice bran oil to be 5:1 and 1 h respectively. The initial quality characteristics (free fatty acid content, oil color, phospholipid content) of crude oil extracted under these optimum conditions were analyzed using various analytical methods based on the standard methods of AOCS and were found to be comparable to the oil extracted with hexane. The initial positive result has paved the way for further studies on issues related to meal qualities as well as to a scale‐up of the method in the near future.  相似文献   
997.
The effect of the organic solvent on the transport of lead ions through a bulk liquid membrane containing dicyclohexano‐18‐crown‐6 (DC18C6) as carrier was studied. Chloroform, 1,2‐dichloroethane, chlorobenzene, nitrobenzene and their binary solutions were employed as solvents. SCN‐, NO3‐, CI‐ and CH3COO‐ were used as anions. The selectivity and the efficiency of lead transport from aqueous solutions containing other cations such as Ni2+, Cu2+, Co2+, and Zn2+ were also investigated.  相似文献   
998.
Polymide 6 (PA 6) molecules can form many different structural modifications depending on the polymer treatment conditions. α-modification is energetically the most stable, has the monoclinic symmetry and originates from the unstable γ*-hexagonal structure. There is still, however, confusion regarding the structure of the second γ modification, resulting from a special treatment with iodine. There are reports about hexagonal [1] and other about monoclinic [2, 3] and even orthorhombic [4, 5] forms of this structure. Given this situation we have applied several treatments to PA 6 monofilament yarn with the purpose of obtaining different structural modifications. Special attention has been given to the formation of the γ-crystalline form. The structural characteristics were investigated using differential scanning calorimetry (DSC), density and X-ray scattering. We have found that the γ-structure obtained after special treatment in iodine solution has the hexagonal symmetry with hydrogen bridges between the parallel chains. Electronic Publication  相似文献   
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Measurements of the impact-ionization multiplication coefficient M-1 in advanced Si BJTs up to values in excess of 10 (corresponding to a peak electric field at the base-collector junction of about 9×105 V/cm) are presented. The intrinsic limitations affecting M-1 measurements at high electric fields are discussed. In particular, the fundamental role played by the negative base current and the parasitic base resistance in determining instabilities during M-1 measurements is pointed out. An accurate theoretical prediction of the M-1 coefficient on collector-base voltages close to BVCBO requires that the contribution of holes to impact ionization be properly accounted for  相似文献   
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