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1.
A series of long-chain quaternary ammonium halogen esters (UKK-chemicals), quaternary dimethyl tallow epoxypropyl ammonium
halogens (EPK1), quaternary ditallow methyl epoxypropyl ammonium halogens (EPK2), and EPK2 oligomers (EPK2P) were synthesized.
At acidic, neutral, or slightly basic conditions, EPK1-, EPK2-, EPK2P-, and UKK-chemicals operate as cationic chemicals. They
can be used, for example, as stock sizings, surface sizings, or fixatives. Stock sizing, surface sizing, and fixative experiments
indicate that EPK1-, EPK2-, EPK2P-, and UKK-chemicals function at least as well as or better than the corresponding synthetic
chemicals used in papermaking. 相似文献
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4.
Jensen-Campbell Lauri A.; Graziano William G.; West Stephen G. 《Canadian Metallurgical Quarterly》1995,68(3):427
Three multimethod studies (total N?=?348) probed the hypothesis that women's attraction to men would be influenced by male prosocial orientation. In Study 1, prosocial men were rated as more physically and sexually attractive, socially desirable, and desirable as dates than were nonprosocial men. Dominant men were no more attractive than low-dominance men, and male dominance did not interact with male prosocial orientation in eliciting attraction from women. In Study 2, prosocial orientation was manipulated to avoid "personalism," but still affected attraction. Across all measures attraction was an interactive function of dominance and prosocial tendencies. Dominance alone did not increase any form of attraction measured. In Study 3, male prosocial tendencies and dominance interacted to affect women's attraction to men. Results are discussed in terms of the place of altruism and dominance in evolutionary approaches to human interpersonal attraction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Lauri PuroAuthor VitaeJeffrey E. TeichAuthor Vitae Hannele WalleniusAuthor VitaeJyrki WalleniusAuthor Vitae 《Decision Support Systems》2011,51(1):31-41
We define and identify bidding strategies in real-life small loan auctions (Prosper.com). In such auctions, lenders bid for borrowers' loan listings and the winners get to fund the loan at an interest rate determined by the auction. The exceptionally large empirical database provided by Prosper.com offers a unique opportunity to test and further develop the theory of online auctions. This study shows that bidding behavior is not homogeneous among bidders, as the traditional auction theory suggests. Instead, bidders use many different bidding strategies. Moreover, learning and bidders' consistency over time in different auctions is studied. 相似文献
6.
Heikki Ailisto Lauri Pohjanheimo Pasi Välkkynen Esko Strömmer Timo Tuomisto Ilkka Korhonen 《Personal and Ubiquitous Computing》2006,10(6):333-344
The prevalent visions of ambient intelligence emphasise natural interaction between user and functions and services embedded in the environment or available through mobile devices. In these scenarios the physical and virtual worlds seamlessly gear into each other, making crossing the border between these worlds natural or even invisible to the user. The bottleneck in reaching these scenarios appear in the natural mapping between the physical objects and their virtual counterparts. The emergence of local connectivity in mobile devices opens possibilities for implementing novel user interface paradigms to enhance this mapping. We present physical selection paradigm for implementing an intuitive human technology interaction for mobile devices. In order to demonstrate the feasibility of the paradigm we implemented two experimental set-ups using commercially available smart phones with IrDA connectivity. The experiments involved selecting a website by physically pointing at its symbol and making a phone call by pointing at an icon representing the person to be called. In tentative user experiments the physical selection method was more time-efficient and it was perceived more positively by the users than a conventional method.
相似文献
Heikki AilistoEmail: |
7.
The North Karelia Project: a programme for community control of cardiovascular diseases 总被引:1,自引:0,他引:1
P Puska K Koskela H Pakarinen P Puumalainen V Soininen J Tuomilehto 《Canadian Metallurgical Quarterly》1976,4(2):57-60
Patients with chronic glomerulonephritis and mild hypertension show a consistent behaviour in their renin-aldosterone-system. There is a close correlation between the elevation of mean blood pressure and destruction of glomeruli. No correlation has been found between renin values and the degree of hypertension. Thus the cuase of mild hypertension occurring in the early stages of chronic GN remains to be elucidated. Normal PRA values in spite of hypertension and expansion of ECFV accompaning progression of chronic glomerulonephritis could be a sign of "relative hyperreninemia". Apparently various mechanisms are involved in the pathogenesis of renal hypertension. These include sodium retention, increased cardiac output. anemia, renin, aldosterone, prostaglandins, expanded plasma volume and peripheral vasoconstriction. These factors are more or less active in the different stages of hypertension and renal failure. 相似文献
8.
Oxidation state of titanium was determined in CaO‐SiO2‐TiOx slags in the composition range 25‐53 percent CaO, 27‐46 percent SiO2, 10‐55 percent TiOx at 1873K using gas equilibration method. In the experiments, slags with different titanium oxide contents were equilibrated with a known carbon monoxide and carbon dioxide ratio. The results were used to determine the Ti3+ and Ti4+ contents as well as the activity coefficient ratio of corresponding oxides in the slag. The dependence of the activity coefficient ratio as a function of oxygen partial pressure was determined. 相似文献
9.
Prime pictures of emotional scenes appeared in parafoveal vision, followed by probe pictures either congruent or incongruent in affective valence. Participants responded whether the probe was pleasant or unpleasant (or whether it portrayed people or animals). Shorter latencies for congruent than for incongruent prime-probe pairs revealed affective priming. This occurred even when visual attention was focused on a concurrent verbal task and when foveal gaze-contingent masking prevented overt attention to the primes but only if these had been preexposed and appeared in the left visual field. The preexposure and laterality patterns were different for affective priming and semantic category priming. Affective priming was independent of the nature of the task (i.e., affective or category judgment), whereas semantic priming was not. The authors conclude that affective processing occurs without overt attention--although it is dependent on resources available for covert attention--and that prior experience of the stimulus is required and right-hemisphere dominance is involved. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
The effect of slightly warm temperature on work performance and comfort in open‐plan offices – a laboratory study 下载免费PDF全文
The aim of the study was to determine the effect of a temperature of 29°C on performance in tasks involving different cognitive demands and to assess the effect on perceived performance, subjective workload, thermal comfort, perceived working conditions, cognitive fatigue, and somatic symptoms in a laboratory with realistic office environment. A comparison was made with a temperature of 23°C. Performance was measured on the basis of six different tasks that reflect different stages of cognitive performance. Thirty‐three students participated in the experiment. The exposure time was 3.5 h in both thermal conditions. Performance was negatively affected by slightly warm temperature in the N‐back working memory task. Temperature had no effect on performance in other tasks focusing on psychomotor, working memory, attention, or long‐term memory capabilities. Temperature had no effect on perceived performance. However, slightly warm temperature caused concentration difficulties. Throat symptoms were found to increase over time at 29°C, but no temporal change was seen at 23°C. No effect of temperature on other symptoms was found. As expected, the differences in thermal comfort were significant. Women perceived a temperature of 23°C colder than men. 相似文献