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61.
In this study, the characteristics of emotional responses to color are explored in two empirical studies. In particular, the relationship between color attributes and emotional dimensions—valence, arousal, and dominance—is analyzed. To account for the cognitive quantity of color, 36 color stimuli were selected following hue and tone categorizations and based on the CIELAB LCh system. In one experiment, the colors were presented on A5‐size glossy paper whereas the identical colors were displayed on CRT monitors in the other experiment. In both experiments, the subjects assessed the emotional responses to each color stimulus using a Self‐Assessment‐Manikin (SAM), which consists of three rows of five pictograms illustrating the three dimensions of emotion, respectively. The empirical results provide evidence that the patterns of affective judgment of colors can be profiled in terms of the three dimensions of emotion (Reliability coefficient, Cronbach's alpha > 0.7). All three attributes of colors, i.e. hue, Chroma, and Lightness, influenced the emotional responses (repeated measurement One‐way ANOVA, P < 0.05), and especially, Chroma was always positively correlated with each of the three emotional dimensions (r > 0.60 P < 0.01). Moreover, the results indicate that emotional responses to color vary more strongly with regard to tone than to hue categories. Comparing the SAM ratings between the two experiments, a systemic explanation has yet to be found to conclude that there is a media effect on the emotional responses to colors. Furthermore, the process of affective judgment of colors and the limit of color as an emotion elicitor are discussed. © 2009 Wiley Periodicals, Inc., Col Res Appl, 2010. 相似文献
62.
Hollow tin dioxide (SnO2) microspheres were synthesized by the simple heat treatment of a mixture composed of tin(IV ) tetrachloride pentahydrate (SnCl4·5H2O) and resorcinol–formaldehyde gel (RF gel). Because hollow structures were formed during the heat treatment, the pre‐formation of template and the adsorption of target precursor on template are unnecessary in the current method, leading to simplified synthetic procedures and facilitating mass production. Field‐emission scanning electron microscopy (FE‐SEM) images showed 1.7–2.5 μm sized hollow spherical particles. Transmission electron microscopy (TEM) images showed that the produced spherical particles are composed of a hollow inner cavity and thin outer shell. When the hollow SnO2 microspheres were used as a lithium‐battery anode, they exhibited extraordinarily high discharge capacities and coulombic efficiency. The reported synthetic procedure is straightforward and inexpensive, and consequently can be readily adopted to produce large quantities of hollow SnO2 microspheres. This straightforward approach can be extended for the synthesis of other hollow microspheres including those obtained from ZrO2 and ZrO2/CeO2 solid solutions. 相似文献
63.
To find a novel high-performance anode material for lithium-ion batteries, a new form of carbon characterized by highly crimped and crystalline nanofibrillar microtextures was produced by heat treating polyacrylonitrile/FeCl3 hybrid precursor and subsequent thermal annealing under hydrogen gas. This form of carbon exhibits a rechargeable capacity of ∼630 mAh/g, which is superior to that of graphite, with a Coulomb efficiency of ∼70%. Further, the new form of carbon was found to exhibit an efficiency of lithium ion insertion/extraction of ∼100% in the voltage range from 0.06 to 0.80 V, with a capacity of ∼400 mAh/g. We speculate that this excellent capacity is due to the characteristic structure of this form of carbon, i.e. its highly entangled web-like hyperstructure consisting of highly crimped and crystalline nanofibrillar microtextures, which enables good permeation and has high resilience to volume deformation during the insertion/extraction of Li ions. 相似文献
64.
Chang Kook Hong Kap Seung Yang Seung Hyun Oh Jou‐Hyeon Ahn Baik‐Hwan Cho Changwoon Nah 《Polymer International》2008,57(12):1357-1362
BACKGROUND: The aim of the work presented was to determine the morphology development and relevant change in fibre diameter of a binary polymer blend system during an electrospinning process. The size of the fibre diameter is one of the important factors determining the general properties of non‐woven mats formed from electrospun fibres. RESULTS: The morphology and diameter of electrospun polyacrylonitrile (PAN)/poly(methyl methacrylate) (PMMA) blends were investigated as a function of blend ratio using scanning electron microscopy. The diameter of the electrospun PAN/PMMA fibres decreased with increasing PMMA content up to 50 wt%, and then increased again with further increase of PMMA. After thermal treatment, the fibres shrank, and an irregularly shaped morphology was observed. CONCLUSION: The electrospinning of incompatible PAN/PMMA blends leads to a microphase‐separation morphology of fibres. A phase inversion occurs at a PMMA content of between 50 and 75 wt%. Due to the phase inversion, the fibre diameter shows a minimum value at the relevant composition. Copyright © 2008 Society of Chemical Industry 相似文献
65.
The formation of N2O in NH3–SCR deNOx reaction over an on-site-used commercial V2O5–WO3/TiO2 catalyst has been measured using an on-line IR system with a modified gas cell. The N2O could be formed by the SCR and NH3 oxidation reactions. These two reactions were particularly enhanced with the on-site-used sample. 相似文献
66.
Hypocholesterolemic Action of Fermented Brown Rice Supplement in Cholesterol-Fed Rats: Cholesterol-lowering Action of Fermented Brown Rice 总被引:3,自引:0,他引:3
Fermented rice products have been implicated in vascular injury and atherosclerosis in recent animal and human studies. In the current study, whether consumption of differently processed brown rice diets may change the cholesterol metabolism was evaluated in male Spraque Dawley (SD) rats after 28 d of treatment with diets containing 1% cholesterol. The experimental diets include corn starch alone as control diet (CO) or a diet containing a 50% substitute of CO; uncooked brown rice (UB), cooked brown rice (CB), lactic acid bacteria (LAB), brown rice mixed with LAB (BLAB), and fermented‐brown rice by LAB (FB), respectively. Among them, FB group elicited significantly lower levels of plasma and hepatic triglycerides, plasma total cholesterol, low‐density lipoprotein cholesterol (LDL‐C), and very low‐density lipoprotein cholesterol (VLDL‐C) by 33% to 50%, whereas higher levels of HDL‐C were elicited by 227% compared with the CO group (P < 0.05). These amelioration action on lipid profile in FB group appeared to correspondent to the higher excretions of fecal weight, triglyceride (TG), total cholesterol (TC), and bile acid (P < 0.05). Furthermore, sensory properties such as flavor liking, taste liking, and overall acceptability of the diet were significantly improved by the addition of fermented brown rice. Conclusively, fermented‐brown rice may have a potent cholesterol‐lowering benefits with sensory quality improvement of the diet. 相似文献
67.
68.
Effects of Different Salt Treatments on the Fermentation Metabolites and Bacterial Profiles of Kimchi 下载免费PDF全文
Dong Wook Kim Bo‐Min Kim Hyeon‐Jeong Lee Gwang‐Ju Jang Seong Hwa Song Jae‐In Lee Sang Bong Lee Jae Min Shim Kang Wook Lee Jeong Hwan Kim Kyung‐Sik Ham Feng Chen Hyun‐Jin Kim 《Journal of food science》2017,82(5):1124-1131
The effects of purified salt (PS) and mineral‐rich sea salt (MRS), both with different mineral profiles, on kimchi fermentation were studied using a culture‐dependent 16S rRNA sequencing technique and mass‐based metabolomic analysis. The different mineral profiles in the fermentation medium caused changes in the bacterial profiles of the 2 kimchi products. An increase of Leuconostoc species in MRS‐kimchi decreased the Lactobacillus/Leuconostoc ratio, which led to changes in metabolites (including sugars, amino acids, organic acids, lipids, sulfur compounds, and terpenoids) associated with kimchi quality. Although further studies on the relationship between these salt types and kimchi fermentation are needed, these results suggested that the MRS treatment had positively affected the changes of the kimchi mineral contents, bacterial growth, and metabolite profiles, which are linked to kimchi quality. 相似文献
69.
Microstructures and tensile behavior of carbon nanotube reinforced Cu matrix nanocomposites 总被引:6,自引:0,他引:6
Kyung Tae Kim Seung Il Cha Seong Hyeon Hong Soon Hyung Hong 《Materials Science and Engineering: A》2006,430(1-2):27-33
Carbon nanotubes (CNTs) have been considered as an ideal reinforcement to improve the mechanical performance of monolithic materials. However, the CNT/metal nanocomposites have shown lower strength than expected. In this study, the CNT reinforced Cu matrix nanocomposites were fabricated by spark plasma sintering (SPS) of high energy ball-milled nano-sized Cu powders with multi-wall CNTs, and followed by cold rolling process. The microstructure of CNT/Cu nanocomposites consists of two regions including CNT/Cu composite region, where most CNTs are distributed, and CNT free Cu matrix region. The stress–strain curves of CNT/Cu nanocomposites show a two-step yielding behavior, which is caused from the microstructural characteristics consisting of two regions and the load transfer between these regions. The CNT/Cu nanocomposites show a tensile strength of 281 MPa, which is approximately 1.6 times higher than that of monolithic Cu. It is confirmed that the key issue to enhance the strength of CNT/metal nanocomposite is homogeneous distribution of CNTs. 相似文献
70.
Young Been Kim Sung Hyeon Jung Dong Su Kim Nishad G. Deshpande Hee Won Suh Hak Hyeon Lee Ji Hoon Choi Ho Seong Lee Hyung Koun Cho 《Advanced functional materials》2021,31(38):2102439
Antimony triselenide (Sb2Se3) nanoflake-based nitrogen dioxide (NO2) sensors exhibit a progressive bifunctional gas-sensing performance, with a rapid alarm for hazardous highly concentrated gases, and an advanced memory-type function for low-concentration (<1 ppm) monitoring repeated under potentially fatal exposure. Rectangular and cuboid shaped Sb2Se3 nanoflakes, comprising van der Waals planes with large surface areas and covalent bond planes with small areas, can rapidly detect a wide range of NO2 gas concentrations from 0.1 to 100 ppm. These Sb2Se3 nanoflakes are found to be suitable for physisorption-based gas sensing owing to their anisotropic quasi-2D crystal structure with extremely enlarged van der Waals planes, where they are humidity-insensitive and consequently exhibit an extremely stable baseline current. The Sb2Se3 nanoflake sensor exhibits a room-temperature/low-voltage operation, which is noticeable owing to its low energy consumption and rapid response even under a NO2 gas flow of only 1 ppm. As a result, the Sb2Se3 nanoflake sensor is suitable for the development of a rapid alarm system. Furthermore, the persistent gas-sensing conductivity of the sensor with a slow decaying current can enable the development of a progressive memory-type sensor that retains the previous signal under irregular gas injection at low concentrations. 相似文献