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Impact of regulatory focus on express packaging waste recycling behavior: moderating role of psychological empowerment perception 全文
2019
Chen, Feiyu | Chen, Hong | Yang, Jiahui | Long, Ruyin | Li, Wenbo
To effectively solve environmental pollution and resource waste problems caused by the rapid growth of express packaging waste, government intervention is needed in the separation and recycling of household waste at the source. Considering the correlation between behavior and individual psychological preference and concerns, this study administered a questionnaire survey (N = 847) and used factor analysis, hierarchical regression, and sensitivity analysis to evaluate the responses and determine the influence of individual focus tendency and empowerment perception on waste recycling behavior. The results showed that individuals with a high prevention focus or a high promotion focus were more likely to have good waste recycling behaviors. Furthermore, the higher the psychological perception of waste recycling empowerment (reflected in the meaning, competence, choice, and impact), the more inclined an individual to participate in recycling and waste reduction activities. In terms of interaction effect, psychological empowerment perception and its dimensions can positively moderate the effect of promotion focus on waste recycling behaviors. In other words, psychological empowerment perception acts as an “amplifier,” and its dimension of meaning was the most important moderating variable. The study results supported policy suggestions to promote individuals’ active participation in waste source separation and recycling activities.
显示更多 [+] 显示较少 [-]Copper-doped TiO2 photocatalysts: application to drinking water by humic matter degradation 全文
2019
Turkten, Nazli | Cinar, Zekiye | Tomruk, Ayse | Bekbolet, Miray
The aim of this study was to determine the photocatalytic performance of copper-doped TiO₂ (Cu-TiO₂) specimens on the degradation of dissolved organic matter (DOM) represented by a model humic acid (HA). TiO₂ was synthesized by sol-gel method from an alkoxide precursor. Cu-doped TiO₂ specimens containing 0.25 wt% and 0.50 wt% Cu were prepared by wet impregnation method using sol-gel synthesized as well as bare TiO₂ P-25 and characterized by XRD, SEM, XPS, Raman spectroscopy, UV-DRS, and BET measurements. Their photocatalytic activities were evaluated with regard to degradation kinetics of HA in terms of UV-vis and fluorescence spectroscopic parameters and organic contents. HA fluorescence excitation emission matrix (EEM) contour plots indicated that the solar photocatalytic degradation pathway was TiO₂-type specific and Cu dopant content.
显示更多 [+] 显示较少 [-]Enhanced selective removal of arsenic(V) using a hybrid nanoscale zirconium molybdate embedded anion exchange resin 全文
2019
Bui, Trung Huu | Hong, Sung Pil | Yoon, Jeyong
Selective removal of trace arsenic is crucial for obtaining safe drinking water. Here, the selective adsorptive performance of arsenate (As(V)) on a hybrid ZMAE (nanoscale zirconium molybdate embedded a macroporous anion exchange resin) was examined. It was found that the As(V) adsorption efficiency of ZMAE was almost retained in the presence of competing ions (NO₃⁻ or SO₄²⁻) up an [SO₄²⁻]/[As] or [NO₃⁻]/[As] ratio of 150/1, whereas that of bare AE (anion exchange resin) was negligible for [SO₄]/[As] over 15/1. In addition, the As(V) maximum adsorption capacity of ZMAE was found to be 41.2 mg/g, which is in contrast with the negligible adsorption of bare AE under sulfate-rich condition. The enhanced arsenate selectivity of ZMAE can be attributed to the excellent selectivity of ZM NPs (zirconium molybdate nanoparticles), which contributed up to 45% of the adsorption capacity of ZMAE. The behavior of ZMAE towards arsenate was compared with that towards phosphate showing similar adsorption performances between them, which indicates the similar affinity of ZMAE towards arsenate and phosphate. Finally, ZMAE examined for fixed-bed column adsorption for As(V) removal from synthetic As(V) water was effective for up to 5100 BVs, treating As(V) from 0.1 mg/L to below 0.01 mg/L (meeting the WHO guidelines).
显示更多 [+] 显示较少 [-]Variations in cadmium accumulation and distribution among different oilseed rape cultivars in Chengdu Plain in China 全文
2019
Wang, Xin | Bai, Jiuyuan | Wang, Jing | Le, Sixiu | Wang, Maolin | Zhao, Yun
Cadmium (Cd) is a widespread toxic heavy metal trace pollutant worldwide. The ability of Cd absorption and accumulation highly varies among different species and varieties. In order to screen oilseed rape cultivars which are appropriate for cultivation and application in Cd-contaminated soils, we conducted the field trial of 32 oilseed rape varieties in Shifang County of Chengdu Plain. The various biomass, Cd accumulation, and distribution patterns were investigated via determining the Cd concentration in different plant tissues. Moreover, the food safety risks of rapeseeds were finally assessed. The results indicated diverse responses to Cd stress appeared in various tested varieties, including plant biomass, seed yield, Cd concentration, and proportion in different tissues. And most Cd were concentrated in non-edible parts. Through cluster analysis, we found that Nanchongjie, Pengzhoubai, and J-25 belong to high-biomass and high-Cd-accumulated groups in experimental cultivars, which indicated that they could possess more biomass and gather higher Cd content in overground part, so they could be great materials for phytoremediation in Cd-polluted area. Besides, combined with the risk assessment of food safety in rapeseeds, cultivars 72A and 47 with the traits of high yield, low-Cd concentration, and low food safety risk can be considered as suitable materials to widely plant as cash crop. These results provide valuable reference for practical planting and application of oilseed rape in Cd-polluted areas.
显示更多 [+] 显示较少 [-]Particulate matters and gaseous pollutants in indoor environment and Association of ultra-fine particulate matters (PM1) with lung function 全文
2019
Akther, Tanzina | Ahmed, Morshad | Shohel, Mohammad | Ferdousi, Farhana Khanom | Salam, Abdus
Real-time particulate matters (PM₁, PM₂.₅, PM₄, PM₇, PM₁₀, and TSP) with AEROCET 531S (USA), gaseous pollutants (NO₂ and TVOC) with Aeroquel 500 gas sampler (NZ) were measured from the indoor air of houses at four residential locations in Dhaka, Bangladesh. PM₁₀ samples were collected on quartz filters with a dual channel dust sampler (IPM-FDS 2510, India) for selected trace metal determination from five houses of Dhaka. Respiratory function of the occupants was assessed by using a peak expiratory flow meter (Rossmax PF 120). Mean PM₁, PM₂.₅, and PM₁₀ concentrations were 46.1 ± 13.4, 76.0 ± 16.2, and 203.9 ± 44.8 μg m⁻³, respectively. Higher enrichment factors of Pb, Zn, and Ni were found for traffic, industrial, and constructional activities. The correlation between indoor and outdoor PM₂.₅ (R² = 0.42) and ratios (I/O < 1) suggesting indoor air was effected by outdoor air. The concentration of NO₂ (0.076 ± 0.007 ppm) and TVOC (90.0 ± 46.0 ppm) was found above than other studies. The average total hazard ratio (THR) in Dhaka was 9.06 and has the highest exposure to air pollutants (PM₂.₅, PM₁₀, NO₂) in Khilkhet (THR 10.1) residents. A negative association between ultra-fine particles (PM₁) and peak flow rate measurements of the residents living in these houses indicates that inhalations of ultra-fine particles has great influence on the reduced lung efficiency.
显示更多 [+] 显示较少 [-]How does urbanization affect carbon emission intensity under a hierarchical nesting structure? Empirical research on the China Yangtze River Delta urban agglomeration 全文
2019
Wang, Feng | Wang, Ge | Liu, Juan | Chen, Hongtao
Urbanization is an important direction for China’s future social development and an important focus of its carbon emission reduction path. China’s current administrative management is a vertical nested structure, and the characteristics of high-scale regions have a non-negligible impact on low-scale areas. Taking the county scale of the basic unit of economic and social development as the research scale, according to the panel data of the Yangtze River Delta from 2008 to 2016, a two-level hierarchical linear model (HLM) for carbon emission intensity is constructed, especially considering the characteristics of high-scale regions (i.e., low-carbon pilot cities) at the second level, and is combined with the mediating effect test method to analyze the impact path of urban development on carbon emissions intensity. The results show that (1) there is a spatial nesting relationship between regions of different scales, and the city scale can explain 85.21% of the carbon emissions intensity, which is much higher than the county scale. (2) There is an N-shaped curve relationship between urban development and carbon emissions intensity. After considering the high-scale factor (low-carbon pilot cities) at the city scale (the second level of the HLM), if a high-scale city is a low-carbon pilot city, then improvement in the level of urbanization in the county can promote a reduction in carbon intensity. (3) The impact path of urban development ⇄ per capita gross domestic product (the proportion of secondary industry, patent application volume) → carbon emissions intensity and urban development → the proportion of tertiary industry → carbon emissions intensity is significant. However, the path of the proportion of tertiary industry → urban development → carbon emissions intensity is not significant.
显示更多 [+] 显示较少 [-]Analysis of uranium removal capacity of anaerobic granular sludge bacterial communities under different initial pH conditions 全文
2019
Zeng, Taotao | Li, Licheng | Mo, Guanhai | Wang, Guohua | Liu, Haiyan | Xie, Shuibo
The bacterial community of an anaerobic granular sludge associated with uranium depletion was investigated following its exposure to uranium under different initial pH conditions (pH 4.5, 5.5, and 6.5). The highest uranium removal efficiency (98.1%) was obtained for the sample with an initial pH of 6.5, which also supported the highest bacterial community richness and diversity. Venn diagrams visualized the decrease in the number of genera present in both the inoculum and the uranium-exposed biomass as the initial pH decreased from 6.5 to 4.5. Compared with the inoculum, a significant increase in the abundances of the phyla Chloroflexi and Proteobacteria was observed following uranium exposure. At initial pH conditions of 6.5 to 4.5, the proportions of the taxa Anaerolineaceae, Chryseobacterium, Acinetobacter, Pseudomonas, and Sulfurovum increased significantly, likely contributing to the observed uranium removal. Uranium exposure induced a greater level of dynamic diversification of bacterial abundances than did the initial pH difference.
显示更多 [+] 显示较少 [-]Correction to: Ginkgo biloba mitigates silver nanoparticles-induced hepatotoxicity in Wistar rats via improvement of mitochondrial biogenesis and antioxidant status 全文
2019
Abd El-Maksoud, Eman M. | Lebda, Mohamed A. | Hashem, Aml E. | Taha, Nabil M. | Kamel, Maher A.
The original publication of this paper contains a mistake. The correct image of figure 3 is shown in this paper.
显示更多 [+] 显示较少 [-]Dental health status and its indicators in adult Brazilian Indians without exposition to drinking water fluoridation: a cross-sectional study 全文
2019
Montanha-Andrade, Katia | Maia, Wolf | Pimentel, Ana Caroline Pereira | Arsati, Ynara Bosco De Oliveira Lima | Santos, Jean Nunes Dos | Cury, Patricia Ramos
Water fluoridation is considered a cost-effective and practical method for controlling and preventing dental caries in the general population. The objective of this study was to evaluate the dental health status and risk indicators for dental caries in adult Brazilian Indians without exposition to dental caries–preventive effects of water fluoridation. Decayed (DT), missing (MT), and filled (FT) permanent teeth (DMFT), as well as plaque index, unstimulated salivary flow rate, salivary buffering capacity, and fasting blood glucose were examined in 225 adult Indians. Smoking habits and sociodemographic data were evaluated using a structured questionnaire. Drinking water samples from 10 Indian villages were analyzed for the natural fluoride concentration. The mean DMFT was 10.33 ± 6.91 (DT, 4.19 ± 3.99; MT, 4.99 ± 5.64; FT, 1.14 ± 1.75). DMFT index ≥ 9 was associated with age ≥ 35 years (p = 0.000), lower education (p = 0.03), and plaque index > 40% (p = 0.003). DT was associated only with plaque index (p = 0.03). MT was associated with age (p < 0.001) and plaque index (p = 0.01). FT was negatively associated with age (p = 0.02) and income (p = 0.02). Fluoride concentration varied from 0.01 to 0.07 mg/L and was not associated with dental health status (p ≥ 0.29). In conclusion, poorer dental health status was associated with older age, higher plaque index, and lower education and income levels. The fluoride level in the drinking water of Kiriri villages was lower than the level recommended for preventing dental caries. Water fluoridation may be recommended for this population.
显示更多 [+] 显示较少 [-]What determines compliance with cleaner production? An appraisal of the tanning industry in Sialkot, Pakistan 全文
2019
Padda, Ihtsham Ul Haq | ʻĀṣim, Muḥammad
Leather tanneries which produce significant amounts of solid waste, effluents, and emissions are a major contributor to industrial waste. A cleaner production program was launched by the government of Pakistan to implement the cleaner production measures for tanneries of Sialkot from 1999 to 2005. The main objective of this study is to identify the impact of a cleaner production program, along with other determinants of a cleaner production in the leather industry. The study analyses firm-level primary data collected from leather tanneries in Sialkot. The primary data were collected from tanneries in Sialkot. The econometric analysis is conducted using the Poisson regression analysis. Overall results show that there is no significant impact of cleaner production in 2015, while the panel data results indicate that the effect of cleaner production support by CPC on cleaner production practices diminished once the support came to an end. The other main factor is firm size, which indicates the financial position of the firm; international and regulator pressures are major determinants of the adoption of cleaner production measures. The analysis also indicates that there is higher probability of large firms adopting a cleaner production in comparison with small ones. Export orientation of firms is another important determinant of cleaner production. The enforcement of the environment compliance laws also has positive effect. The compliance with cleaner production measures is quite low, at 6.4 out of 19 cleaner production practice measures. There is a need to adopt measures that are environmentally friendly and are favorable towards both labor health and product quality, which are important for the sustainable growth of the tanning industry.
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