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Provenance tracing of dust using rare earth elements in recent snow deposited during the pre-monsoon season from mountain glaciers in the central to northern Tibetan Plateau Full text
2021
Zheng, Kui | Li, Yuefang | Li, Zhen | Huang, Ju
To provide insight into dust sources in snow deposited during the non-monsoon period on the Tibetan Plateau, detailed post-Archean Australian shale (PAAS)-normalized rare earth element (REE) distribution patterns and variations in REE tracers, such as La/Yb, La/Er, and Gd/Yb with depth, as well as the distribution of samples in the plots of REE ratio pairs, such as La/Yb vs. Y/ΣREE, La/Er vs. Gd/Er, and Y/La vs. Nd/Er, were compared in seven potential dust source areas in Asia. Snow samples from five glaciers, i.e., Qiumianleike (QMLK), Meikuang (MK), Yuzhufeng (YZF), Xiaodongkemadi (XDKMD), and Gurenhekou (GRHK), were collected from April 26 to May 13 before the onset of monsoon activity. The results show that dust trapped in snow pits from the studied glaciers, i.e., QMLK, MK, XDKMD, and GRHK, has varying degrees of contribution from the Taklimakan Desert, Qaidam Basin, and the surface soil of the Tibetan Plateau. There are signals of the Tengger and Badain Jaran Desert and Chinese Loess in the MK and XDKMD snow pit samples or in the QMLK and GRHK surface samples from the REE tracers; however, from the point of view of the land location, the three dust sources should not be the major contributors. Signals of dust from the Indian Thar Desert were occasionally detected from the MK, YZF, and XDKMD snow pit samples and GRHK surface snow samples, implying the intrusion of early Indian monsoon activities to the sites. The dust signal from the Thar Desert in India from the YZF glacier is significantly greater than that from the XDKMD and MK glaciers. These findings were also supported by the tracer of dust transmitted to the three snow pits through the air mass backward trajectories. The new finding of this study is that dust from the Indian Desert can even reach the Kunlun Mountains in the northern region of the Tibetan Plateau. The conclusions are helpful in interpreting the sources of dust and the pollutants absorbed by dust particles, as well as the extent of the impact of Indian monsoon activities at the end of the non-monsoon season on the plateau.
Show more [+] Less [-]Effect of sulfur dioxide exposure on histopathology and morphometry of pancreatic islet cells and glycemic indices in Wistar rats Full text
2021
Soltan-Abad, Razieh Musapour | Kheirouri, Sorayya | Abbasi, Mehran Mesgari | Alizadeh, Mohammad | Khordadmehr, Monireh
Sulfur dioxide (SO₂) is a ubiquitous air pollutant. Recent studies suggest that SO₂ is a momentous risk factor for diabetes mellitus (DM). The present investigation aimed to evaluate the effects of SO₂ exposure on histopathology and morphometry of pancreatic islet cells and serum glycemic indices in rats. Sixteen male Wistar rats were divided equally into SO₂ and control groups. SO₂ group was exposed to 10 parts per million (ppm) SO₂ for 5 weeks (6 days a week, 3 h/day) and control group to filtered air for the same time as SO₂ group. Blood serums were collected and pancreatic tissue isolated. Glycemic indices were measured. Pathological and morphometric changes were studied in the pancreatic tissues. Exposure to SO₂ caused a significant increase in blood glucose but did not significantly change insulin and HbA1c serum levels and HOMA-IR. There were significant differences in vascular congestion (p= 0.02) and insulitis (p= 0.04) between the groups. SO₂ inhalation significantly reduced beta cell number and beta-alpha cell ratio compared with the control group (p=0.03 and p<0.0001, respectively). These findings suggest that SO₂ exposure damages pancreatic tissue which subsequently influences either the incidence of DM or the trend of diabetic complications.
Show more [+] Less [-]Environmental Applications of Nanotechnology: Nano-enabled Remediation Processes in Water, Soil and Air Treatment Full text
2021
Linley, Stuart | Thomson, Neil R.
Environmental remediation is a research field transformed over the past two decades by the integration of engineered nanoscale materials. The market for nanotechnology in environmental applications is rapidly growing, signifying the importance of such advancements in practice as well as research. Most nano-enabled remediation challenges in water, soil and air treatment are addressed by two primary phenomena—contaminant degradation by reduction/oxidation reactions or contaminant sequestration through adsorption processes. Despite the scientific accessibility of these fields by virtue of their shared treatment mechanisms, the unique engineering and physical challenges associated with implementation require field-specific solutions and create research bubbles where scientists and engineers may be unfamiliar with current research in parallel areas. Consequently, this review is focused on summarizing the key nano-enabled technologies and their mechanisms in the fields of water, soil and air treatment, as well as describing recent advances and highlighting areas with clear direction for further development. This review covers nano-enabled processes including photocatalysis in air and water treatment, nZVI-mediated reduction and adsorption processes in soil and water treatment, and CO₂ capture and reduction including the state-of-the-art materials driving research focused on improving these technologies. This review is intended as a platform for researchers to understand how their expertise fits into the larger community of remediation technology as well as to provide direction for literature review of parallel fields suiting their interest. We conclude by identifying core research focuses and underdeveloped research directions in each of the three areas, most notably, a need for guided evaluation of meaningful composite materials for next-generation catalysts.
Show more [+] Less [-]Experimental studies of thermal performance of an evacuated tube heat pipe solar collector in Polish climatic conditions Full text
2021
Siuta-Olcha, Alicja | Cholewa, Tomasz | Dopieralska-Howoruszko, Kinga
This work presents the results of experimental studies on the energy performance of an evacuated solar collector, heat pipe type, consisting of 24 tubes, over the period of 2 months. The solar collector with a gross area of 3.9 m² is part the solar hot water test system located in Lublin (Poland). The effect of the weather conditions and operating parameters on the thermal and exergy efficiencies of the evacuated tube solar collector has been defined. The solar irradiation per month for July amounted to 80 kWh/m², and for August, it equalled 112.8 kWh/m². The average thermal gain was found to be in July 163 W/m² and in August 145 W/m², respectively. For the considered study period, the average value of energy yield in the solar collector was obtained at the level of 4.28 MJ/(m²·d). The average monthly energy efficiencies of the solar collector in July and August were 45.3% and 32.9%, respectively, while the average monthly exergy efficiencies reached 2.62% and 2.15%, respectively. Increasing the wind speed to 0.86 m/s decreases the thermal efficiency and the exergy efficiency by 67% and 41%, respectively.
Show more [+] Less [-]Environmental conservation value of an endangered species: the case of Cypripedium Japonicum Full text
2021
Kim, Ju-Hee | Kim, Chang-Min | Yoo, Seung-Hoon
The South Korean government is seeking information on the environmental conservation value (ECV) of Cypripedium japonicum, a plant on the first-level priority endangered species list of the Korea Ministry of Environment, as well as on the Red List of the International Union for Conservation of Nature. This research paper aims to assess the ECV by employing contingent valuation (CV) to elicit people’s willingness to pay (WTP) for its conservation. To achieve this aim, in May 2020, a CV survey of 1,000 interviewees in South Korea was carried out employing a closed-ended question. The average household WTP is estimated to be KRW 3,770 (USD 3.07) per annum and secures statistical significance. From a national point of view, using information on the national population, this value comes to KRW 76.72 billion (USD 62.42 million) per year. Although the cost of conserving the species has not yet been accurately estimated, the ECV seems to be larger than the cost of conservation. Thus, it is socially desirable to conserve Cypripedium japonicum, and the conservation should be carried out in a stable and continuous manner.
Show more [+] Less [-]Efficient abatement of NOx emitted from automotive engines via adsorption on the Ba-CMK-3 adsorbents Full text
2021
Wu, Runping | Ye, Qing | Wu, Kai | Dai, Hongxing
The Ba-CMK-3(x) (x was the Ba(NO₃)₂:CMK-3 mass ratio and equals to 5, 10, and 15 wt%) samples were prepared by the incipient impregnation method, which were used for the adsorption of NO + O₂ at room temperature. The samples were characterized by the XRD, BET, TEM, TPD, TG, and DRIFTS techniques. The results showed that the CMK-3 and Ba-CMK-3(x) samples possessed an ordered two-dimensional hexagonal mesoporous structure, and Ba was uniformly dispersed on the surface of CMK-3. After Ba doping, the surface areas and pore size distributions of the Ba-CMK-3(x) samples were altered due to the synergistic effect of partial blocking of the channels by Ba and partial etching of the carbon materials by O₂ produced from Ba(NO₂)₃ decomposition at high temperatures. The sequence in NO adsorption capacity was Ba-CMK-3(10) (108.1 ± 0.55 mg/g) > Ba-CMK-3(15) (106.2 ± 0.72 mg/g) > Ba-CMK-3(5) (102.3 ± 1.33 mg/g) > CMK-3(88.8 ± 1.15 mg/g), with the Ba-CMK-3(10) sample showing the best (NO + O₂) adsorption performance. We proposed the two main adsorption pathways in the process of NO adsorption: (i) NO reacted with O₂ to form NO₂, part of NO₂ were weakly adsorbed on the surface hydroxyl groups, part of NO₂ were adsorbed to form the nitrite and nitrate species, and the left NO₂ was disproportionated to the NO, NO₂⁻, and NO₃⁻ species; and (ii) NO was directly oxidized to the NO₂⁻ species by the oxygen-containing functional groups in carbon, and then some of the NO₂⁻ species were transformed to the NO₃⁻ species directly or via disproportionation. The regeneration efficiencies of the Ba-CMK-3(x) samples were slightly inferior to that of the CMK-3 sample.
Show more [+] Less [-]In situ bioremediation of Fenton’s reaction–treated oil spill site, with a soil inoculum, slow release additives, and methyl-β-cyclodextrin Full text
2021
Talvenmäki, Harri | Saartama, Niina | Haukka, Anna | Lepikkö, Katri | Pajunen, Virpi | Punkari, Milla | Yan, Guoyong | Sinkkonen, Aki | Piepponen, Tuomas | Silvennoinen, Hannu | Romantschuk, Martin
In situ bioremediation of Fenton’s reaction–treated oil spill site, with a soil inoculum, slow release additives, and methyl-β-cyclodextrin Full text
2021
Talvenmäki, Harri | Saartama, Niina | Haukka, Anna | Lepikkö, Katri | Pajunen, Virpi | Punkari, Milla | Yan, Guoyong | Sinkkonen, Aki | Piepponen, Tuomas | Silvennoinen, Hannu | Romantschuk, Martin
A residential lot impacted by spills from a leaking light heating oil tank was treated with a combination of chemical oxidation and bioremediation to avoid technically challenging excavation. The tank left emptied in the ground was used for slow infiltration of the remediation additives to the low permeability, clayey soil. First, hydrogen peroxide and citrate chelate was added for Fenton’s reaction–based chemical oxidation, resulting in a ca. 50% reduction from the initial 25,000 mg/kg average oil concentration in the soil below the tank. Part of this was likely achieved through mobilization of oily soil into the tank, which was beneficial in regards to the following biological treatment. By first adding live bacteria in a soil inoculum, and then oxygen and nutrients in different forms, an approximately 90% average reduction was achieved. To further enhance the effect, methyl-β-cyclodextrin surfactant (CD) was added, resulting finally in a 98% reduction from the initial average level. The applicability of the surfactant was based on laboratory-scale tests demonstrating that CD promoted oil degradation and, unlike pine soap, was not utilized by the bacteria as a carbon source, and thus inhibiting degradation of oils regardless of the positive effect on biological activity. The effect of CD on water solubility for different hydrocarbon fractions was tested to serve as the basis for risk assessment requirements for authorizing the use of the surfactant at the site.
Show more [+] Less [-]In situ bioremediation of Fenton’s reaction–treated oil spill site, with a soil inoculum, slow release additives, and methyl-β-cyclodextrin Full text
2021
Talvenmäki, Harri | Saartama, Niina | Haukka, Anna | Lepikkö, Katri | Pajunen, Virpi | Punkari, Milla | Yan, Guoyong | Sinkkonen, Aki | Piepponen, Tuomas | Silvennoinen, Hannu | Romantschuk, Martin | https://orcid.org/0000-0002-6821-553X | 4100210510 | Luonnonvarakeskus
Transition to sustainable transport: understanding the antecedents of consumer’s intention to adopt electric vehicles from the emotional research perspective Full text
2021
Xu, Guowei | Wang, Shanyong | Zhao, Dingtao
Electric vehicles (EVs) are recognized as one of the effective measures to realize sustainable transport. Therefore, many countries have issued related policy initiatives and measures to promote EVs. However, consumer’s cognition and acceptance of EVs is not ideal, which affects the early diffusion speed of EVs on the market. This research attempts to explore how consumer’s driving experience affects EVs adoption intention from the perspective of consumer’s emotional response (satisfaction and trust) by using stimulus-organism-response framework. Based on the analysis of 692 sample data collected through questionnaire survey, we found that consumer’s driving experience has a significant and positive impact on EVs adoption intention. Meanwhile, driving experience also significantly and positively affects consumer’s satisfaction while has no significant effect on trust. Furthermore, satisfaction has a significantly positive effect on trust, and satisfaction and trust are both significantly and positively associated with EVs adoption intention. The results further uncovered that satisfaction not only plays a mediating role between driving experience and adoption intention but also plays a multiple mediating role between driving experience and adoption intention together with trust. On this basis, relevant recommendations have been made to promote the development of EVs from the perspective of government and enterprise.
Show more [+] Less [-]Experimental Study on the Effect of the Physicochemical Properties of Contaminated Fillers in Bioretention System on Microbial Community Structure Full text
2021
Li, Yajiao | Yang, Yaou | Zhang, Jingyu | Zhang, Zhaoxin | Li, Jiake
Six bioretention filter columns were designed to study the effects of the bioretention system on surface runoff reduction through rainfall simulation water distribution experiments, and the relationship between the physicochemical properties of contaminated fillers and microbial community structure was analyzed. Results show that (1) the water volume and load reduction effect of traditional bioretention soil media (BSM) + 5% water treatment residue (WTR) was better than that of traditional bioretention soil media; (2) soil moisture content (SMC), carbon, nitrogen, phosphorus, Cd, and Cu increased after the water distribution test, while the change of Zn in the filter columns varied; (3) species richness decreased after the experiment. In terms of microbial community structure, the top 10 dominant phyla did not change. At the genus level, Arthrobacter replaced Sphingomonas as the most abundant flora after the experiment; (4) the effects of the physicochemical properties of contaminated fillers on microbial community structure in terms of pH were not clear, but total organic carbon(TOC), total phosphorus(TP), and SMC greatly influenced the microbial community structure, while the influence of heavy metals on the relative abundance at the phylum and genus levels was not uniform.
Show more [+] Less [-]Utilization of different plant species for dewatering of sewage sludge Full text
2021
El-Gendy, Ahmed Shafik | Ahmed, Amira Galal
Bench-scale and pilot-scale experiments were conducted in an outdoor environment to study the ability of some plant species in dewatering of sewage sludge collected from biological activated sludge treatment. In the bench-scale experiments, four types of plants were tested, including water hyacinth (Eichhornia crassipes), common reed (Phragmites austuralis), Samar (Cyperus alopecuroides), and El Nesila (Panicum echinochloa). Sludge dewatering in the plant reactors was compared with that in the control reactors (no plants). The bench-scale experiments were conducted in reactors with capacities of 17 L. All plants showed a growth in the sewage sludge matrix. High dewatering efficiencies of sewage sludge were obtained with the use of each type of plant, as compared with those in the controls. Among other plants tested in the current study, water hyacinth proved to have the highest dewatering efficiency and was selected for further testing in a pilot-scale experiment. Two identical drying beds were constructed as a pilot-scale, each with its own multi-layered underdrainage system. The plants were added to one of the beds while the other bed served as a control. The pilot study showed that the use of water hyacinth in conventional sludge drying beds can triple the sludge dewatering capacity of these beds. In addition, the quality of the dewatered sludge was also improved compared with that found in conventional drying beds.
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