Sorption of Non-ionic Aromatic Organics to Mineral Micropores: Interactive Effect of Cation Hydration and Mineral Charge Density

Prestasi pemisahan sistem membran penuras nano didapati sangat bergantung kepada kesan sterik dan cas. Kajian terdahulu telah menunjukkan bahawa kombinasi yang tepat di antara saiz liang (kesan sterik) dan ketumpatan cas berkesannya (kesan Donnan) akan memberikan prestasi pemisahan yang optimum. Justeru itu, keupayaan menghasilkan membran penuras nano bersifat optimum akan memberikan pembaikan yang signifikan dari aspek prestasi membran dan pengurangan kos pemprosesan. Oleh itu, objektif utama kajian teoritikal ini ialah untuk menyelidik kesan interaktif saiz liang (rp) dan ketumpatan cas membran, (Xd) terhadap prestasi pemisahan. Dua parameter tanpa dimensi telah digunakan iaitu λ (λ = rs/rp) dan ζ(ζ = Xd/Cb). Pengangkutan elektrolit melalui membran penuras nano tersebut ditentukan dengan menggunakan model liang sterik-donnan (DSPM). Pelbagai larutan garam dengan pelbagai saiz liang dan kesan cas diuji dengan menggunakan model tersebut. Kajian menunjukkan bahawa untuk kes membran dengan kapasiti cas berkesan yang tinggi, faktor Donnan didapati lebih penting untuk membran yang longgar strukturnya. Sumbangan faktor Donnan ini berkurangan dengan peningkatan saiz liang membran. Sebaliknya, untuk membran berketumpatan cas yang rendah, kesan faktor Donnan terhadap tolakan ion boleh diabaikan, tanpa bergantung kepada saiz liang. Kata kunci: Penurasan nano, DSPM, ketumpatan caj berkesan, saiz liang, teoritikal The separation performance of NF membrane system is found to be significantly dependent on the steric and charge effects. Previous studies have shown that the right combination of membrane pore size (steric effect) and its effective charge density (donnan effect) will lead to an optimum separation performance. Hence, the ability to produce nanofiltration membranes with optimized properties will certainly provide significant improvement in terms of membrane performance and processing cost reduction. Therefore, the main objective of this theoretical study is to investigate the interactive effect of membrane pore size (rp) and membrane charge density, (Xd) towards the separation performance. Two general dimensionless parameters were used namely λ (λ = rs/rp) and ζ(ζ = Xd/Cb). The electrolyte transport through nanofiltration membranes is determined using a model based on the application of the extended Nernst–Planck equation coupled with Donnan–steric pore model (DSPM). A variety of salt solution with various pore size and charge effect was tested using the above–mentioned model. It was found that for the case of membranes with high effective charge density, the Donnan factor is more prominent for loose membranes. The contribution of the factor decreased with the increase of membrane pore size. Vice versa, for the lower charge density membrane, the effect of Donnan factor towards ion rejection could be neglected, regardless of membrane pore sizes. Key words: Nanofiltration, DSPM, membrane charge density, pore size, theoretical

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Incommensurate modulated phases of the NbxTa1-xTe4 charge density wave system

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100120692 ◽

1992 ◽

Vol 50 (1) ◽

pp. 58-59

Author(s):

S. Ritchie ◽

J. C. Bennett ◽

A. Prodan ◽

F.W. Boswell ◽

J.M. Corbett

Keyword(s):

Charge Density ◽

Charge Density Wave ◽

Direct Evidence ◽

Density Wave ◽

Wave System ◽

Modulated Phases ◽

Metal Atoms ◽

Incommensurate Modulation ◽

End Members ◽

Modulation Wave Vector

A continuous sequence of compounds having composition NbxTa1-xTe4; 0 ≤ x ≤ 1 have been studied by electron diffraction and microscopy. Previous studies have shown that the end members of the series, TaTε4 and NbTε4 possess a quasi-one-dimensional character and exhibit charge density wave (CDW) distortions. In these compounds, the subcell structure is tetragonal with axes (a × a × c) and consists of the metal atoms (Nb or Ta) centered within an extended antiprismatic cage of Te atoms. At room temperature, TaTε4 has a commensurate modulation structure with a 2a × 2a × 3c unit cell. In NbTε4, an incommensurate modulation with × ∼ 16c axes is observed. Preliminary studies of the mixed compounds NbxTα1-xTε4 showed a discontinuous jump of the modulation wave vector commensurate to incommensurate when the Nb dopant concentration x, exceeded x ≃ 0.3, In this paper, the nature of the compositional dependence of is studied in greater detail and evidence is presented for a stepwise variation of . This constitutes the first direct evidence for a Devil's staircase in CDW materials.

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Individual Differences in the Name Similarity Effect

Journal of Individual Differences ◽

10.1027/1614-0001/a000133 ◽

2014 ◽

Vol 35 (2) ◽

pp. 111-118

Author(s):

Daniel J. Howard ◽

Roger A. Kerin

Keyword(s):

Individual Differences ◽

Impression Management ◽

Interactive Effect ◽

Purchase Intentions ◽

Brand Attitude ◽

Self Monitoring ◽

Similarity Effect ◽

And Behavior ◽

Usage Context

The name similarity effect is the tendency to like people, places, and things with names similar to our own. Although many researchers have examined name similarity effects on preferences and behavior, no research to date has examined whether individual differences exist in susceptibility to those effects. This research reports the results of two experiments that examine the role of self-monitoring in moderating name similarity effects. In the first experiment, name similarity effects on brand attitude and purchase intentions were found to be stronger for respondents high, rather than low, in self-monitoring. In the second experiment, the interactive effect observed in the first study was found to be especially true in a public (vs. private) usage context. These findings are consistent with theoretical expectations of name similarity effects as an expression of egotism manifested in the image and impression management concerns of high self-monitors.

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When Apologies for Injustice Matter

European Psychologist ◽

10.1027/1016-9040.13.4.239 ◽

2008 ◽

Vol 13 (4) ◽

pp. 239-247 ◽

Cited By ~ 26

Author(s):

David De Cremer ◽

Barbara C. Schouten

Keyword(s):

Laboratory Study ◽

Interaction Effect ◽

Interactive Effect ◽

Cross Sectional ◽

Fairness Perceptions ◽

Organizational Survey ◽

Experimental Laboratory

The present research examined the idea that the effectiveness of apologies on promoting fairness perceptions depends on how meaningful and sincere the apology is experienced. More precisely, it was predicted that apologies are more effective when they are communicated by an authority being respectful to others. A study using a cross-sectional organizational survey showed that an apology (relative to giving no apology) revealed higher fairness perceptions, but only so when the authority was respectful rather than disrespectful. In a subsequent experimental laboratory study the same interaction effect (as in Study 1) on fairness perceptions was found. In addition, a similar interaction effect also emerged on participants’ self-evaluations in terms of relational appreciation (i.e., feeling valued and likeable). Finally, these self-evaluations accounted (at least partly) for the interactive effect on fairness perceptions.

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Interactive Effect of Dispositional Cognitive Avoidance, Magnitude of Threat, and Response Efficacy on the Persuasive Impact of Threat Communications

Journal of Individual Differences ◽

10.1027/1614-0001/a000077 ◽

2012 ◽

Vol 33 (2) ◽

pp. 94-100 ◽

Cited By ~ 2

Author(s):

Steffen Nestler ◽

Boris Egloff

Keyword(s):

Individual Differences ◽

Interactive Effect ◽

Cognitive Avoidance ◽

Effective Response ◽

Response Efficacy ◽

Internet Study ◽

High Threat

This internet study investigated the effect of individual differences in cognitive avoidance on the persuasive impact of threat communications. A total of 289 participants completed a measure of dispositional cognitive avoidance and read either a high- or a low-threat communication that provided either an effective response to reduce the threat or not. We found that cognitive avoidance did not moderate the effect of magnitude of threat when response efficacy was low. By contrast, cognitive avoidance was relevant when efficacy was high: After a high-threat message, low cognitive avoiders reported more favorable attitudes toward and intentions to adopt the action recommendation than high cognitive avoiders. Further analyses showed that severity perceptions mediate this effect of avoidance on attitudes and intentions. Individual differences in cognitive avoidance are thus an important moderator of the effectiveness of threat communications.

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