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Non-oxidative propane dehydrogenation is an endothermic reaction requiring thermally stable and regenerable catalysts to produce propylene. In this work, we investigate bimetallic CoXNi2-XP as an alternative, non-noble metal propane dehydrogenation catalyst. Co1Ni1P displayed higher propylene selectivity than Co2P and higher site-normalized propylene production rates than Ni2P. Different compositions of CoXNi2-XP catalysts were evaluated for propane dehydrogenation with oxidative regeneration in between each cycle. Ni-rich Co0.5Ni1.5P showed increased propylene production upon regeneration due to the formation of the Ni12P5 phase during reaction. In contrast, Co1Ni1P and Co1.25Ni0.75P showed the ability to recover > 50% of the initial activity for at least 3 oxidative regenerations, while maintaining high propylene selectivity without any phase change. This study showcases the enhancement in stability and propane dehydrogenation performance of Ni2P through Co incorporation and Ni:Co ratio control. [ABSTRACT FROM AUTHOR]

Low-temperature non-thermal plasmas produce highly reactive chemical environments made up of electrons, ions, radicals, and vibrationally excited molecules. These reactive species, when combined with catalysts, can help drive thermodynamically unfavorable chemical reactions at low temperatures and atmospheric pressure. The conversion of methane (CH4) to produce other value-added chemicals is a good model system because of its applicability to a wide range of industries. To effectively create these plasma catalytic systems, a fundamental understanding of the plasma-phase chemistry alone is imperative. While there have been many studies on methane plasmas and how certain operating conditions (i.e., gas composition and power) affect the plasma, there is limited understanding on how changing bulk reaction temperature affects the plasma properties and ensuing plasma chemistry. In this work, we use a dielectric barrier discharge to investigate the effects of temperature on the reaction chemistry and the plasma's electrical properties in various methane-gas mixtures. Results show that increasing temperature leads to a reduction in methane conversion as well as changes to both the gas and dielectric material pre-breakdown, which manifests itself in temperature-dependent electrical properties of the plasma. Experiments at various temperatures and power show a positive correlation between key electrical plasma properties (average charge and lifetime per filament) and the measured methane conversion as a function of temperature. [ABSTRACT FROM AUTHOR]

Remembering to fulfill an intention at a later time often requires people to monitor the environment for cues that it is time to act. This monitoring involves the strategic allocation of attentional resources, ramping attention up more in some contexts than others. In addition to interfering with ongoing task performance, flexibly shifting attention may affect whether task-irrelevant information is later remembered. In the present investigation, we manipulated contextual expectations in event-related prospective memory (PM) to examine the consequences of flexible attention allocation on incidental memory. Across two experiments, participants completed a color-matching task while monitoring for ill-defined (Experiment 1) or specific (Experiment 2) PM targets. To manipulate contextual expectations, some participants were explicitly told about the trial types in which PM targets could (or not) appear, while others were given less precise or no expectations. Across experiments, participants' color-matching decisions were slower in high-expectation trials, relative to trials when targets were not expected. Additionally, participants had better incidental memory for PM-irrelevant items from high-expectation trials, but only when they received explicit contextual expectations. These results confirm that participants flexibly allocate attention based on explicit trial-by-trial expectations. Furthermore, the present study indicates that greater attention to item identity yields better incidental memory even for PM-irrelevant items, irrespective of processing time. [ABSTRACT FROM AUTHOR]

Although false memories have largely been examined with the Deese-Roediger-McDermott (DRM) paradigm, little research has focused on the semantic context in which associates are encoded. Across three experiments, we varied semantic context during a sentence-processing task with DRM associates embedded within sentences. More meaningful sentences resulted in greater memory errors (Experiment 1). Furthermore, providing contextual information to discriminate old from new items did not reduce false alarms relative to encoding words in isolation when sentences converged on the meaning of the critical lure (Experiment 2), and actually increased memory errors (Experiment 3). These results suggest that semantic context that allows for meaningful relational processing of items within-lists and that converge on the semantic meaning of the critical lure increases the likelihood that the list theme is identified, resulting in more errors at test. [ABSTRACT FROM AUTHOR]

Prospective memory (PM) is typically measured using keypresses in laboratory paradigms, which therefore assess only discrete, stage-like processes. In the present study we manipulated focal and nonfocal PM cue conditions, as well as participants' focus on different aspects of the PM/ongoing task set, using the methodology to capture dynamic computer mouse movements. The software captured mouse trajectories during lexical decisions and PM responses. We replicated many findings typical in the PM literature, including the accuracy advantage for focal over nonfocal conditions and longer ongoing-task response times for nonfocal conditions. Participants' movement trajectories during PM responses revealed evidence for both spontaneous-retrieval and strategic-monitoring processes in focal and nonfocal PM retrieval conditions. During trials suggestive of spontaneous retrieval, mouse trajectories initially went toward the typical ongoing-task response but turned mid-trajectory toward the PM response field on the opposite side of the computer screen. In nonfocal conditions, these trajectory reversals had a wider arc and took longer to complete, reflecting the likely greater retrospective retrieval requirements of nonfocal conditions. Regarding what are more likely to be strategic-monitoring processes, a significant portion of responses traveled directly to the PM response field, as though people were prepared to make such a response. [ABSTRACT FROM AUTHOR]

We explored 2 research questions: whether criterion shifts within different recognition tasks are reliable across testing sessions and whether such shifts correlate across the different tasks. In Experiment 1, we established consistent group-level criterion shifting based on expected strength of target items in the test. False-alarm rates were higher when expected strength was weak as opposed to strong, even when expected strength cues were unblocked at test. Test-retest reliabilities in this strength-cuing environment were good. In Experiment 2, we manipulated either the probability (high or low) or expected memory strength (strong or weak) of target items and had people perform both tasks on each of 2 days of testing. Varying the probability of target items consistently produced criterion shifts, as did manipulating target memory strength. Regarding individual differences, shifting in a given test context predicted shifting on a second day in that same test context. However, one's tendency to shift a decision criterion on 1 type of test context did not predict one's tendency to do so in the other. The extent to which people shifted their decision criterion in recognition memory testing was largely dependent on the type of test. [ABSTRACT FROM AUTHOR]

In three experiments we explored cross-dimensional cuing effects in a multidimensional source encoding and retrieval paradigm. We employed a bias-controlled experimental method of source cuing at retrieval (Starns & Hicks, ) in an attempt to improve retrieval of location information indirectly by cuing gender information. Encoded words were situated on the left or right side of a computer monitor and associated with either a male or a female face. When multiple faces were used across the set of encoded words, reinstating the correct face at retrieval alongside an incorrect, opposite-gender face cue improved male/female source decisions for test words. However, this powerful test cue did not improve memory for the encoded location of the words, suggesting that within-dimension cuing does not produce cross-dimensional cuing. This null outcome was found when gender decisions were required (Experiments 1A and 2) or not required (Experiment 1B) prior to location decisions. Nor was cross-dimension cuing found when subjects were told to expect a source test of both gender and location information at retrieval (Experiment 2). Our findings reinforce prior work demonstrating that multiple context dimensions can be bound to item information without any direct binding between the contexts. [ABSTRACT FROM AUTHOR]

In seven experiments, we explored the potential for strength-based, within-list criterion shifts in recognition memory. People studied a mix of target words, some presented four times (strong) and others studied once (weak). In Experiments 1, 2, 4A, and 4B, the test was organized into alternating blocks of 10, 20, or 40 trials. Each block contained lures intermixed with strong targets only or weak targets only. In strength-cued conditions, test probes appeared in a unique font color for strong and weak blocks. In the uncued conditions of Experiments 1 and 2, similar strength blocks were tested, but strength was not cued with font color. False alarms to lures were lower in blocks containing strong target words, as compared with lures in blocks containing weak targets, but only when strength was cued with font color. Providing test feedback in Experiment 2 did not alter these results. In Experiments 3A-3C, test items were presented in a random order (i.e., not blocked by strength). Of these three experiments, only one demonstrated a significant shift even though strength cues were provided. Overall, the criterion shift was larger and more reliable as block size increased, and the shift occurred only when strength was cued with font color. These results clarify the factors that affect participants' willingness to change their response criterion within a test list. [ABSTRACT FROM AUTHOR]

Reinstating source details at test often has no impact on source memory. We tested the proposition that participants internally reinstate source cues when such cues are not provided by the experimenter, thus making the external cues redundant. Participants studied words paired with either a male or a female face and were later asked to specify the gender of the face studied with each word. To disrupt the ability to internally reinstate sources, some participants saw eight male faces and eight female faces throughout the study list (multiple-face condition), making it difficult to determine which face should be internally reinstated for uncued test trials. Other participants saw only a single face for each gender (single-face condition), which should facilitate internal reinstatement. Across three experiments, participants in the multiple-face condition showed improved source discrimination when the studied faces were reinstated at test, as compared to uncued trials. In contrast, participants in the single-face condition showed no effect of the face cues. Moreover, the cuing effect for the multiple-face condition disappeared when the test structure facilitated internal reinstatement. Overall, the experiments support the contention that internal reinstatement is a natural part of source retrieval that can mask the effects of external cues. [ABSTRACT FROM AUTHOR]

We report the synthesis of multifunctional, hierarchical, cerium-containing HZSM-5 catalysts with various aluminum and cerium contents using a dry-gel, dual templating method. The catalysts were characterized by X-ray diffraction, N physisorption, scanning electron microscopy, diffuse reflectance UV-Visible spectroscopy, diffuse reflectance Fourier transform infrared spectroscopy, Fourier transform Raman spectroscopy, NH temperature programmed desorption and X-ray photoelectron spectroscopy. At low theoretical Si:Al ratios (15 and 20), the formation of amorphous silica-alumina materials was observed. However, at higher theoretical Si:Al ratios (30, 40, and 50), crystalline materials were formed. Furthermore, with Si:Al ratios of 50, cerium incorporation as high as 2.2 wt% was obtained using this procedure. To understand the role of aluminum and cerium in the catalyst, the crystalline materials were studied in the catalytic fast pyrolysis of glucose at 600 °C. The catalysts with cerium incorporated showed an increase in the production of oxygenated chemicals as well as CO, compared with their non-cerium containing analogs. [ABSTRACT FROM AUTHOR]

A positive relationship between prior knowledge and item memory is a consistent finding in the literature. In the present study, we sought to determine whether this relationship extends to episodic details that are present at the time of encoding, namely source memory. Using a novel experimental design, we were able to show both between- and within-subjects effects of prior knowledge on source memory. Specifically, the results revealed that the degree of prior knowledge positively predicted memory for source specifying contextual details. In addition, by including two conditions in which attention was divided either at encoding or retrieval, we were able to show that prior knowledge influences memory by affecting encoding processes. Overall, the data suggest that a priori knowledge within a specific domain allows attentional resources to be allocated toward the encoding of contextual details. [ABSTRACT FROM AUTHOR]

In this study, we examined a source-monitoring phenomenon that arises from reactivated related information from the study phase. Three experiments showed that source attributions for target events were influenced not only by the target item itself, but also by studied information about related items. In Experiment 1, source memory for target items that have a high forward association value to a single related study item (e.g., credit) were affected by the source of the associated information (e.g., card), so that memory performance was better when associated items were presented in the same source rather than a different source. A similar effect occurred with bidirectional associates (Exp. 2), as well as with synonymous pairs of words (Exp. 3). We argue that the source information of the reactivated material can be commingled with information about a candidate during a source judgment at retrieval and thereby can affect performance. [ABSTRACT FROM AUTHOR]

In four experiments, we compared binding between item and context information with binding between different types of context information. Participants studied line drawings of common objects that appeared in both different colors and different locations. We explored the effects of reinstating one type of information on recognition memory for another type, and we also tested the participants' ability to discriminate intact from rearranged pairings of two types of information. Results showed that different contextual dimensions (i.e., color and location) were bound to item information (i.e., object information), but not to each other. [ABSTRACT FROM AUTHOR]

We report three experiments investigating source memory for words that were called "new" on a recognition test. In each experiment, participants could accurately specify the source of words that they failed to recognize. Results also demonstrated that source memory for unrecognized items varied with the bias to respond "old" in recognition decisions: Participants displayed unrecognized source memory when they were told that 25% of the recognition test words were old (promoting conservative responding) but not when they were told that 75% of the test words were old (promoting liberal responding). Our results were successfully predicted by a multivariate signal detection approach to recognition/source memory. [ABSTRACT FROM AUTHOR]

Source monitoring for valenced materials has received very little attention from researchers interested in the residual effects that emotion can have on memory. The three previous studies that examined memory for valenced material found a source-monitoring enhancement effect. By contrast, we used two different combinations of sources and found a novel, consistent source-monitoring deficit for valenced words as compared with neutral ones. In addition, this memory deficit for contextual details did not consistently covary with item memory. We assert that it is possible to obtain an effect in which heightened attention toward valenced material reduces the binding of contextual details into memory. [ABSTRACT FROM AUTHOR]

Task interference occurs in prospective memory tasks when an intention deleteriously affects performance on an ongoing activity in some way. Several studies have shown that task interference can manifest itself in slower latencies to perform an ongoing task. Recent evidence demonstrates that associating intentions to certain performance contexts affects prospective memory performance (see, e.g., Cook Marsh, & Hicks, 2005). In the present study, an intention was associated with a particular stimulus class, such as pictures or words. We found that task interference could be reduced when participants could reliably predict that the material about to be processed was irrelevant to the intention. This material-specific interference effect was found on a trial-by-trial basis in a random sequence of two different kinds of materials across two experiments and with blocking manipulation in another experiment. These results demonstrate that task interference is not a monolithic construct rather, it results from dynamic and flexible attentional allocation strategies that can change on a trial-by-trial basis. [ABSTRACT FROM AUTHOR]

High-context-variability (HCV) items are experienced in many more preexperimental semantic contexts than are low-context-variability (LCV) items. LCV confers an advantage to recognition memory (Steyvers & Malmberg, 2003). In the present study, we tested whether or not that advantage could be caused by enhanced source memory. Both context variability and word frequency were manipulated, and both factors generally affected source monitoring. Accuracy was better for LCV items than for HCV items and better for low-than for high-word-frequency items. We also considered whether context variability exerts its influence at encoding or at retrieval. We concluded that better recognition memory for LCV items was due, in part to better retrieval of contextual details that specify how an item was originally studied. [ABSTRACT FROM AUTHOR]

One of the current issues in the field of prospective memory concerns whether having an intention produces a cost to other ongoing activities (called task interference). The evidence to date suggests that certain intentions held over the shorter term do interfere with other tasks. Because the cumulative effect of such costs would be prohibitively expensive in everyday life, the present study examined one means by which that interference may be reduced. Participants who formed a specific association to fulfilling an intention in a future context did not exhibit task interference over the intervening period until that context was encountered. This outcome was observed with both an event-based and a time-based prospective memory task The results suggest that associating intention fulfillment with a specific context can eliminate task interference, and they emphasize the importance of studying intentions that are linked to future contexts versus those that are not. [ABSTRACT FROM AUTHOR]

Context variability refers to the number of preexperimental contexts that are associated with concepts. In four experiments, we investigated the basis for increased recognition memory for low context variability words. Low context variability was associated with greater recollection in the hit rates, and high context variability was associated with greater familiarity in the false alarms. Shortening the study time reduced recollection, but low context variability still influenced recollection in the hit rates. A modality change from study to test also reduced recollection but preserved recollective differences for low versus high context variability items. One interpretation of the results suggests that low context variability evokes more specific and, perhaps, idiosyncratic recollective associations during learning and that these associations support better recognition in the hit rates. By contrast, activating the larger number of associations for high context variability items may be mistaken for familiarity in the false alarm rates. [ABSTRACT FROM AUTHOR]

In two experiments, we tested whether false recognition and false recall were prone to retrieval- induced forgetting, using the retrieval practice paradigm (Anderson, Bjork, & Bjork, 1994). Participants encoded lists of cue-target word pairs associated with a nonpresented, critical theme word and then engaged in retrieval practice for half of the word pairs from half of the lists. As expected, unpracticed targets from practiced lists were recognized (Experiment 1) and recalled (Experiment 2) less well than those from unpracticed lists. In addition, false recognition and false recall of critical items associated with practiced lists was lower than false recognition and false recall of items associated with unpracticed lists. We argue that false memories are prone to inhibitory mechanisms engendered by the retrieval practice paradigm. The results are consistent with the claim that semantically activated critical themes interfere with the episodic retrieval of list words and that inhibition decreases the activation level of these interfering memory representations during retrieval practice. [ABSTRACT FROM AUTHOR]

Investigates the output monitoring component of event-based prospective memory performance. Elaboration of prospective memory performance; Influence of performance on the incidence of repetition and omission errors in memory tasks; Examination of behavioral consequences.

Assesses the recall performance of students from the University of Georgia. Impact of recall failure on predictive judgments; Comparison between cued and free recall performance; Accuracy of predictive remember-know judgments; Identification of collective details to be among the partial knowledge retrieved in the absence of successful cued recall.

Examines the intention superiority effect which is the finding that intentions to perform an activity are stored in a heightened state of activation. Presence of intention superiority effect in constellation of unrelated activities; Inhibition effect of cancelling the intention; Practical consequences for daily prospective memory by activation and inhibition of intentions.

Investigates prospective memory, through the use of a naturalistic paradigm. Reference to research on prospective memory; Definition of prospective memory; Details on experiments conducted; Information on participants in the experiments; Results of these experiments; Discussion on these results.