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991.
为全面推进生态文明建设、加强生态环境保护,政府和企业正积极探索激励个人绿色消费的有效措施。随着游戏化应用的日益普及,以游戏化助推绿色消费行为的研究愈加受到关注,但尚未形成系统的理论框架。本综述首先对游戏化的要素、设计框架以及示能性进行了系统回顾。然后分别从动机、态度和行为3个方面分析梳理了绿色消费的研究现状,并根据绿色消费的特点提出了间接绿色消费行为的概念。最后,本综述基于对游戏化助推绿色消费行为相关文献的研究分析,构建了一个探究游戏化助推绿色消费行为的总体研究框架。该框架强调游戏化对个人的绿色消费动机、态度、行为均产生助推作用,为相关领域的探索提供了研究思路。 相似文献
992.
Xuan Minh Pham Nguyen Thi Nguyen Thang Van Bui Nhu Huynh Thi Nguyen Thao Minh Nguyen Pha Ngoc Bui Ngoc Nhu Thi Nguyen Mai Thanh Phong Van-Huy Nguyen Le-Hai Tran 《应用聚合物科学杂志》2024,141(1):e54749
In this study, the semi-aromatic polyamide membranes were synthesized by the interfacial polymerization between piperazine (PIP) monomers in the water phase and Benzene-1,3,5-tricarbonyl chloride in the organic phase. To further modify the semi-aromatic pervaporation membrane, the two amino acids, glycine, and l -lysine, were mixed with PIP monomers for interfacial polymerization. The morphology and physicochemical properties of the synthesized membranes were analyzed using Fourier transform infrared (FTIR), field emission scanning electron microscope (FE-SEM), atomic force microscope (AFM), and contact angle measurements. The results show that the semi-aromatic polyamide membranes modified by the two amino acids possess a higher hydrophilic surface and lower thickness compared to the unmodified membrane. Additionally, the permeation flux of the semi-aromatic polyamide membranes was improved by 18.6% and 38.5% as modified with glycine and l -lysine, respectively, at the operating temperature of 70°C when the rejection of both NaCl and arsenic are higher than 99.8%. Furthermore, the operating temperature significantly influenced the permeation flux, while the salt rejections were insignificantly affected. The permeation flux increases by 3.2- and 4.0-folds for glycine and lysine-modified membranes, respectively, when elevating the feed temperature from 40°C to 70°C. The highest permeation flux of 29.5 kg m−2 h−1 with a 5 wt% NaCl rejection of 99.8% was obtained at 70°C by using 0.3 wt% l -lysine modified polyamide (PA) membrane. For elimination of 1.5 mg L−1 As solution at the feed temperature of 70°C, such l -lysine modified PA membrane exhibited the permeation flux of 30.5 kg m−2 h−1 and As rejection of 99.6%, respectively. This work provides a cost-saving, facile, and eco-friendly preparation method for effectively improving the permeation flux while not sacrificing the high rejection of salts of the modified membranes. 相似文献
993.
Sokunbi MO Staff RT Waiter GD Ahearn TS Fox HC Deary IJ Starr JM Whalley LJ Murray AD 《IEEE transactions on bio-medical engineering》2011,58(11):3206-3214
We investigated the association between individual differences in cognitive performance in old age and the approximate entropy (ApEn) measured from functional magnetic resonance imaging (fMRI) data acquired from 40 participants of the Aberdeen Birth Cohort 1936 (ABC1936), while undergoing a visual information processing task: inspection time (IT). Participants took a version of the Moray House Test (MHT) No. 12 at age 11, a valid measure of childhood intelligence. The same individuals completed a test of non-verbal reasoning (Raven's Standard Progressive Matrices [RPM]) aged about 68 years. The IT, MHT and RPM scores were used as indicators of cognitive performance. Our results show that higher regional signal entropy is associated with better cognitive performance. This finding was independent of ability in childhood but not independent of current cognitive ability. ApEn is used for the first time to identify a potential source of individual differences in cognitive ability using fMRI data. 相似文献
994.
Conventional two-step algorithm, long latency of interpolation and various motion vectors are three factors that mainly induce high computation complexity of fractional motion estimation and also prevent it from encoding high-definition video. In order to overcome these obstacles, a high performance fractional motion engine is proposed in this paper with three techniques. First, based on high correlation between motion vector of a block and its up-layer as well as relationship of integer candidates, one-step algorithm is proposed. Second, an 8×4 element block processing is adopted, which not only eliminates almost redundancies in interpolation, but also still ensures hardware reusability. Finally, a scheme of processing 4×4 and 4×8 block with free of cycles is presented, so that the number of motion vectors can be reduced up to 59%. Experimental results show that the proposed design just needs 50% of gate count and 56% of cycles when compared with previous design while nearly maintaining the coding performance. 相似文献
995.
The Cane Resources Network for Southern Africa evaluated how bioenergy from sugarcane can support sustainable development and improve global competitiveness in the region. The assessment of six countries with good contemporary potential for expanding sugarcane cultivation described in this paper was part of their analysis. Its principal objective was to identify land where such production will not have detrimental environmental and/or socio-economic impacts. Geographic Information Systems (GIS) was used to interrogate 1 km2 resolution protected area, land cover, climate, elevation and soil data sets. To avoid detrimental impacts on biodiversity, all categories of protected areas, closed canopy forests and wetlands were excluded. To safeguard food security, all areas under food and/or cash crop production were excluded. Areas unsuitable because of climate, terrain and soil constraints were also excluded. The assessment found that almost 6 million hectares of suitable land is available in these countries, clearly suggesting that ‘land’ is unlikely to be a limiting factor in harnessing sugarcane’s bioenergy potential in the region. However, land identified as such in this study needs to be verified using better resolution, preferably ground, information. 相似文献
996.
997.
Particle size is a very important variable in semi-autogenous grinding processes. It is desirable to measure the variable efficiently or even predict its variations in advance. In this paper, the time delay neural network model is developed to predict the feed particle size of a semi-autogenous grinding mill, and the Levenberg–Marquardt algorithm is used to train the network. Results show that the model predicted values fit well with the industrial operating data. The proposed model can predict the particle size in advance and allow adequate time to take corrective actions during abnormal operations, and therefore provide a great advantage in monitoring and control of the industrial processes. 相似文献
998.
999.
Nabil T. Fadai Rahil Sachak-Patwa Helen M. Byrne Philip K. Maini Mona Bafadhel Dan V. Nicolau Jr 《Journal of the Royal Society Interface》2021,18(175)
While the pathological mechanisms in COVID-19 illness are still poorly understood, it is increasingly clear that high levels of pro-inflammatory mediators play a major role in clinical deterioration in patients with severe disease. Current evidence points to a hyperinflammatory state as the driver of respiratory compromise in severe COVID-19 disease, with a clinical trajectory resembling acute respiratory distress syndrome, but how this ‘runaway train’ inflammatory response emerges and is maintained is not known. Here, we present the first mathematical model of lung hyperinflammation due to SARS-CoV-2 infection. This model is based on a network of purported mechanistic and physiological pathways linking together five distinct biochemical species involved in the inflammatory response. Simulations of our model give rise to distinct qualitative classes of COVID-19 patients: (i) individuals who naturally clear the virus, (ii) asymptomatic carriers and (iii–v) individuals who develop a case of mild, moderate, or severe illness. These findings, supported by a comprehensive sensitivity analysis, point to potential therapeutic interventions to prevent the emergence of hyperinflammation. Specifically, we suggest that early intervention with a locally acting anti-inflammatory agent (such as inhaled corticosteroids) may effectively blockade the pathological hyperinflammatory reaction as it emerges. 相似文献
1000.
The adoption of liquefied petroleum gas vehicles is strongly linked to the break-even distance at which they have the same costs as conventional cars, with very limited market penetration at break-even distances above 40,000 km. Hydrogen vehicles are predicted to have costs by 2030 that should give them a break-even distance of less than this critical level. It will be necessary to ensure that there are sufficient refuelling stations for hydrogen to be a convenient choice for drivers. While additional LPG stations have led to increases in vehicle numbers, and increases in vehicles have been followed by greater numbers of refuelling stations, these effects are too small to give self-sustaining growth. Supportive policies for both vehicles and refuelling stations will be required. 相似文献