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41.
The deposition of dyes onto lightly colored garments, or onto lighter sections of multicolored garments, during laundry results in fabric discoloration. In particular, there is a requirement to restrict indigo dye transfer between garments. Polymers may be added to detergent formulations as dye transfer inhibitors to prevent dye transfer by blocking the deposition of fugitive dyes in aqueous solution. This article reports the generation of a range of dye transfer inhibitors produced by condensation reactions that are effective in preventing the transfer of unbound indigo dye to a variety of fiber types. Key design rules relating to polymer hydrophilicity and pendant polymer functionality were established for the creation of effective dye transfer inhibitors. Remarkably, polymers at concentrations as low as 0.1 mg/ml were found to be effective in inhibiting indigo deposition on a variety of fiber types, offering great promise for their inclusion within laundry detergent formulations as dye transfer inhibitors.  相似文献   
42.
Research has not resolved whether depression is associated with a distinct information-processing bias, whether the content of the information-processing bias in depression is specific to themes of loss and sadness, or whether biases are consistent across the tasks most commonly used to assess attention and memory processing. In the present study, participants diagnosed with major depression, social phobia, or no Axis I disorder, completed several information-processing tasks assessing attention and memory for sad, socially threatening, physically threatening, and positive stimuli. As predicted, depressed participants exhibited specific biases for stimuli connoting sadness; social phobic participants did not evidence such specificity for threat stimuli. It is important to note that the different measures of bias in memory and attention were not systematically intercorrelated. Implications for the study of cognitive bias in depression, and for cognitive theory more broadly, are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
43.
A supramolecular approach was undertaken to create functionally activatable cell‐penetrating peptides. Two tetra‐arginines were assembled into an active cell‐penetrating peptide by heterodimerizing leucine zippers. Three different leucine‐zipper pairs were evaluated: activation was found to depend on the association constant of the coiled‐coil peptides. The weaker‐binding peptides required an additional disulfide linkage to induce cell‐penetrating capability, whereas for the most‐stable coiled‐coil no additional stabilization was needed. The latter zipper pair was used to show that the induced formation of the coiled coils allows control over the uptake of an oligoarginine CPP‐conjugated cargo protein.  相似文献   
44.
Thin film sensor systems based on hydrogenated carbon have the advantage to combine two very important characteristics in order to be used in measurement engineering: Firstly, the sensory layer demonstrates piezoresistive behavior and secondly its good properties related to hardness and wear resistance lead in a tribologically stable system. Therefore, the thin film sensor systems can be applied into the main distribution of force within machine parts or used for universal interchangeable sensor systems, e.g. sensory washers. In this article the deposition of a self-contained thin film sensor system on a large technical component (spindle shaft) is shown. The spindle shaft with a length of 480 mm and an outer diameter of 90 mm is part of a belt driven machining spindle for planing machines in woodworking industries. In order to establish a measurement system, which allows monitoring the clamping force of the tool holder and the imbalance of the mounted tool, the thin film sensor system was directly applied to the front surface of the spindle shaft. For this application a novel self-contained thin film sensor system was developed, which consists of an alumina layer for electrical isolation, a chromium layer to establish internal sensor electrodes, a piezoresistive hydrogenated carbon layer (1 μm) and a second covering wear resistance and insulation layer (silicon and oxygen modified carbon layer). The piezoresistive sensor layer and the top layer are part of the diamond like carbon layer family (Robertson, Diam Relat Mater 12:79–84, 2003; Bewilogua et al. DLC based coatings for tribological applications, pp. 67–75, 2006; Biehl et al. Thin Solid Films 515(3):1171–1175, 2006, Novel measurement and monitoring system for forming processes based on piezoresistive thin film systems. Springer Verlag, pp. 879–883, 2010).  相似文献   
45.
Conversion of NOx with reducing agents H2, CO and CH4, with and without O2, H2O, and CO2 were studied with catalysts based on MOR zeolite loaded with palladium and cerium. The catalysts reached high NOx to N2 conversion with H2 and CO (>90% conversion and N2 selectivity) range under lean conditions. The formation of N2O is absent in the presence of both H2 and CO together with oxygen in the feed, which will be the case in lean engine exhaust. PdMOR shows synergic co-operation between H2 and CO at 450–500 K. The positive effect of cerium is significant in the case of H2 and CH4 reducing agent but is less obvious with H2/CO mixture and under lean conditions. Cerium lowers the reducibility of Pd species in the zeolite micropores. The catalysts showed excellent stability at temperatures up to 673 K in a feed with 2500 ppm CH4, 500 ppm NO, 5% O2, 10% H2O (0–1% H2), N2 balance but deactivation is noticed at higher temperatures. Combining results of the present study with those of previous studies it shows that the PdMOR-based catalysts are good catalysts for NOx reduction with H2, CO, hydrocarbons, alcohols and aldehydes under lean conditions at temperatures up to 673 K.  相似文献   
46.
Prolonged sitting is a potential health risk, not only for people with an inactive lifestyle but also for those who meet the daily physical activity recommendations. Mobile applications that trigger people to take regular breaks from sitting seem promising. In this paper, we present the results of our quest to create effective persuasive mobile applications aimed at reducing sedentary behavior. First, we developed SitCoach, a mobile application to nudge office workers from their seats. SitCoach monitors physical activity and sedentary behavior and provides timely persuasive messages suggesting active breaks. A user test showed that users had little awareness of the risks of prolonged sitting and considered their ability to take active breaks to be highly dependent on external factors. The results from this study formed the basis for a second experiment, which was more extensive in duration and number of participants. In this 6-week experiment, office workers received timely persuasive messages on their smart phones, advising them to take an active break whenever they were sitting behind their computer for too long. Compared to a Control group who did not receive these messages, a significant decrease in computer activity was achieved. The studies show the potential and limitations of using a smart phone as a platform for reducing sedentary behavior. We conclude with recommendations to create effective mobile applications that motivate people to take regular breaks from sitting.  相似文献   
47.
This paper offers a simplified model in which an agency is in charge of investing in road capacity and maintain it but cannot use the capital market so that the only sources of funds are the toll revenues. We refer to this requirement as the ’strict self-financing constraint’ to distinguish it from the traditional form for self-financing that allows borrowing from the capital market. Two small test problems are analysed: the one link problem and the problem of two parallel links with one link untolled. The numerical illustrations show the cost of the strict self-financing constraint as a function of the importance of the initial infrastructure stock, the rate of growth of demand, the price elasticity of demand and the flexibility in the pricing instruments.  相似文献   
48.
Motorcyclists have a relative high risk of crash involvement. As a consequence there is an on-going search for safety measures to improve road safety for motorcyclists. One popular measure is motorcycle training. Although intuitively sound, there are only few thorough studies on rider training courses and they do not always show a positive safety effect.  相似文献   
49.
This qualitative inquiry explores how self-identified Arabs living in the United States express their collective identities in talk. Twenty-one participant observations, 50 interviews, and 4 group discussions were conducted with first- and second-generation Arabs of Druze, Muslim, and Christian faiths. Identity labels were identified as a means of communication for expressing collective identities. The participants in this study identified themselves as a heterogeneous group with intersecting and evolving collective identities that were affirmed and refuted in social interactions. Self-identification as "Arab,""Arab American,""Muslim," or "Iraqi" depended on such situational factors as audience, physical setting, and September 11. Although some respondents dropped the label "Arab" after September 11 to avoid discrimination, others started to self-identify as "Arab American." The findings add to the literature on culture, identity, and communication by illustrating the importance of identity terms for personal and communal relationships, problematizing the definition of large identity groups a priori as ethnic, national, or cultural, describing the social and communicative consequences of self- and other-ascribed identities, and highlighting the impact of September 11 on Arab identity expressions in the United States.  相似文献   
50.
Carotenoids and vitamin E in oils from the market – 6 rapeseed and 6 sunflower oils, half of each cold pressed and refined – and in the oils of rape, sunflower, flax and safflower as well as the respective seeds and press cakes from a local oil mill were quantified by HPLC. Furthermore, a photometric determination of carotenoid content was tested and checked against the chromatographic method. In the cold pressed oils minor amounts of xanthophylls (allE)‐lutein and (allE)‐zeaxanthin were determined. With exception of traces of (allE)‐β‐carotene in cold‐pressed rapeseed oil this provitamin A active compound did not occur. Cold pressed rapeseed oils contained 0.5–1.5 mg total carotenoids/100 g which was manifold the content of the further oils. Vitamin E was found in all vegetable oils at plant‐typic tocopherol patterns. The photometric determination of carotenoids resulted in significantly higher concentrations compared to the HPLC. This overestimation bases on the carotenoid pattern which was validated by comparison with known high‐carotenoid materials, i.e. maize flour with an abundant amount of xanthophylls and carrots with an abundant amount of carotenes.  相似文献   
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