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Design of natural elements in open spaces of cities with a Mediterranean climate, conditions for comfort and urban ecology Полный текст
2018
Gómez, Francisco | Valcuende, Manuel | Matzarakis, Andreas | Cárcel, Javier
More than half the world’s population lives in cities that were designed with a complete disregard for nature. Then, it is vital that nature should be present in these spaces to provide ecological support for urban areas. Natural elements that are in these spaces should be designed with people’s comfort in mind. This research explores the application of the PET and UTCI biometeorological comfort indices in urban microspaces, where the general environmental parameters of the city are not valid and each space must be measured individually. The research looked into the influence of the design of natural elements on improving comfort. The results show that in the children’s playing spaces, the absence of thermal comfort and considerable thermal stress were detected in summer. This effect is more easily seen in the PET values. The benefits to comfort of having double layers of vegetation in the gardens have also been shown. The micro-droplets of water from the jets in the fountains are carried by the breeze and modify the human-biometeorological conditions around the fountains and reduce thermal stress. This improvement needs an appropriate design of the fountains and an awareness of the breeze patterns in these spaces.
Показать больше [+] Меньше [-]Liquid chromatography-mass spectrometry method for evaluating the dissipation dynamics of cyromazine and its metabolite in Agaricus bisporus and dietary risk assessment Полный текст
2018
Zhao, Zhiyong | Chen, Lei | Bai, Bing | Yang, Xianli | Tan, Yanglan | Wang, Jianhua | Zhao, Xiaoyan | Zhou, Changyan
Providing guidance on the reasonable use of pesticide in agricultural production is of particular importance for ensuring food safety. In the present study, a field trial was performed to study the dissipation and accumulative pattern of cyromazine (CA) and its metabolite in Agaricus bisporus (A. bisporus) cultivation. An ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was first developed and validated for the determination of CA and melamine (MEL) in the casing soil and fruiting body. During the cultivation period, the dissipation rates of CA in the casing soil were between 51.57 and 63.48% at three dose groups. The fruiting body presented higher accumulation ability for MEL compared with CA. The terminal residues of MEL never exceeded the maximum residue limits (MRLs) in food. In addition, the intake health risk from the CA and MEL residues in the fruiting body were negligible to humans. This study will help to provide valuable guidance on the application strategies of CA in A. bisporus cultivation.
Показать больше [+] Меньше [-]Analysis of the results of empirical research and surveys of perceived indoor temperature depending on gender and seasons Полный текст
2018
Sulewska, Maria Jolanta | Gładyszewska-Fiedoruk, Katarzyna | Sztulc, Piotr
The indoor thermal condition tests were conducted as real and declared by the respondents. The tests were carried out in the laboratory room in Bialystok. The object is a detached, two-storey building with a cellar. The tests were carried out from February to May 2015. In 1 week, on average, ten measurement series were carried out. During one experiment series, there were between 10 and 15 students present in the room. The aim of the publication is to analyze the results of declared perceived temperature tests in the room depending on the gender, the season and indoor and outdoor temperature conditions. On the basis of statistical analysis of the test results, it was found that in the analyzed age group, the perceived temperature declared in the room is not affected by the respondent’s gender. The conclusion is that the temperature sensations of young (and probably healthy) people who do not do physical work are similar, regardless of gender. Differences between the average perceived temperature in the room, declared by all respondents in winter and declared in spring are statistically significant. The indoor perceived temperature declared in the winter is almost constant and does not depend on the temperature of the perceived temperature of outdoor air.
Показать больше [+] Меньше [-]Effect of calcination temperature on the properties of Ti/SnO2-Sb anode and its performance in Ni-EDTA electrochemical degradation Полный текст
2018
Lei, Xin | Li, Lianghao | Chen, Yuancai | Hu, Yongyou
Pd-doped Ti/SnO₂-Sb anode was prepared at different calcination temperatures by a wet-impregnation method and employed in simultaneous electrochemical catalytic degradation of Ni-EDTA and recovery of nickel. The results showed that Ti/SnO₂-Sb-Pd-500 could achieve the highest electrochemical activity (87.5% of Ni-EDTA removal efficiency), superior durability (50.7 h of accelerated lifetime), and higher Ni recovery (19.8%) on cathode. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) analysis suggested that Ni-EDTA degradation on anode was mainly indirect oxidation-controlled reaction, attributing to the high oxide state of MOX ₊ ₁ and MOX(·OH), rather than direct oxidation. Scanning electron microscope (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) analyses indicated that calcination temperature could modify the morphology of electrode surface and affect the incorporation and valence state transformation of metal species (Sb and Pd) in SnO₂ lattice. Ti/SnO₂-Sb-Pd-500 achieved the highest electrochemical capacity with the highest levels of adsorbed oxygen Oₐdₛ/ET (27.11%) and lattice oxygen Oₗₐₜ/ET (29.69%). Moreover, the operation conditions for Ni-EDTA electrochemical degradation were optimized. These findings were valuable for developing a high-performance electrode for Ni-EDTA electrochemical degradation.
Показать больше [+] Меньше [-]Lead-induced changes of cytoskeletal protein is involved in the pathological basis in mice brain Полный текст
2018
Ge, Yaming | Chen, Lingli | Sun, Xianghe | Yin, Zhihong | Song, Xiaochao | Li, Chong | Liu, Junwei | An, Zhixing | Yang, Xuefeng | Ning, Hongmei
Lead poisoning is a geochemical disease. On the other hand, lead is highly carcinogenic and exhibits liver and kidney toxicity. This element can also cross the blood-brain barrier, reduce learning and memory ability and damage the structure of the cerebral cortex and hippocampus. To further investigate the mechanism of lead neurotoxicity, 4-week-old Kunming mice were used to explore the effects of different concentrations of Pb²⁺ (0, 2.4, 4.8 and 9.6 mM) for 9 days. In this study, pathological and ultrastructural changes in brain cells of the treated group were related to damages to mitochondria, chromatin and the nucleus. Lead content in blood was tested by atomic absorption spectroscopy, which showed high lead concentrations in the blood with increasing doses of lead. Distribution of lead in nerve cells was analysed by transmission electron microscopy with energy dispersive spectroscopy. Data showed the presence of lead in nucleopores, chromatin and nuclear membrane of nerve cells in the treatment groups, whereas lead content increased with increasing doses of lead acetate. Finally, microtubule-associated protein 2 (MAP2) mRNA and protein expression levels were detected by real-time PCR and Western blotting, which showed a reduction in MAP2 expression with increasing lead doses in the mouse brain. These findings suggest that acute lead poisoning can cause significant dose-dependent toxic effects on mouse brain function and can contribute to better understanding of lead-induced toxicity.
Показать больше [+] Меньше [-]Effect of H2O on the NO emission characteristics of pulverized coal during oxy-fuel combustion Полный текст
2018
Lei, Ming | Sun, Cen | Zou, Chan | Mi, Hang | Wang, Chunbo
The NO emission characteristics of Datong bituminous coal and Yangquan anthracite in O₂/H₂O/CO₂ atmospheres were investigated by using a fixed-bed reactor system, and the emission characteristics were compared with the experimental results from O₂/N₂ and O₂/CO₂ atmospheres, especially at low O₂ concentrations and high temperatures. The results showed that NO emissions of pulverized coal in O₂/CO₂ environments were less than those in the O₂/N₂ environments, regardless of the O₂ concentration and the furnace temperature. Adding H₂O decreased the possibility of reactions between the reductive groups (NH) and the oxygen radical during devolatilization, which led to a decrease in NO emissions at 1000 °C. However, as the furnace temperature increased, “additional” nitrogen precursors (HCN and NH₃) generated by enhanced char-H₂O gasification were quickly oxidized to generate a large amount of NO during char oxidation that exceeded the amount of NO reduced by NH during devolatilization. Thus, the NO emissions in O₂/CO₂/H₂O atmosphere were higher than those in O₂/CO₂ atmosphere at a low O₂ concentration. However, as the O₂ concentration increased, the NO emissions in O₂/CO₂/H₂O atmosphere became lower than those in O₂/CO₂ atmosphere because the effect of H₂O gasification became weaker. The NO emissions of Yangquan anthracite (YQ) were higher than those of DT, but the changing trend of YQ was similar to that of DT.
Показать больше [+] Меньше [-]A novel approach to evaluate potential risk of organic enrichment in marine aquaculture farms: a case study in Sanggou Bay Полный текст
2018
Yang, Shu | Yang, Qian | Song, Xianli | Liu, Sai | Qu, Keming | Sun, Yao
A novel approach was proposed to evaluate the potential risk of organic enrichment in marine aquaculture farms without obvious environmental degradation. The approach was based on historical environmental records preserved in sediment cores, and potential risk of organic enrichment can be effectively evaluated by comparing burial fluxes of marine organic carbon (OCM) during times before and after large-scale aquaculture. A case study was conducted in Sanggou Bay. The change trends on burial fluxes of organic carbon in sediment over the past 150 years were rebuilt. OCM burial fluxes have greatly increased since the beginning of large-scale aquaculture in 1980s, reaching 16.0~16.5 times higher than that before large-scale aquaculture. The results indicate that aquaculture activities have resulted in obvious accumulation of aquacultural organic matters, although sedimental environment has not degraded seriously. Besides, if the OCM burial fluxes further increase to 3.5~7.0 times higher than that in present, sedimental environment may degrade obviously. Therefore, potential risks of organic enrichment still exist with aquaculture development in Sanggou Bay.
Показать больше [+] Меньше [-]Magnesium depletion suppresses the anti-grazer colony formation in Scenedesmus obliquus Полный текст
2018
Hou, Xinying | Zhou, Qiming | Wang, Zeshuang | Kong, Qingdan | Sun, Yunfei | Zhang, Lu | Zhu, Xuexia | Huang, Yuan | Yang, Zhou
In aquatic ecosystems, many phytoplankton species have evolved various inducible defense mechanisms against the predation. The expression of these defenses is affected by environmental conditions such as nutrient availability. Here, we investigated the anti-grazer colony formation in Scenedesmus obliquus at different magnesium concentrations (0–7.3 mg L⁻¹ Mg²⁺) in the presence of zooplankton (Daphnia)-derived infochemicals. Results showed that at adequate Mg²⁺, S. obliquus formed high proportions of multi-celled (e.g., four- and eight-celled) colonies, resulting in significantly increased number of cells per colony in response to Daphnia filtrate. On the other hand, in Mg²⁺-deficient treatment, the proportion of multi-celled colonies decreased, together with reduced algal growth rate and photosynthetic efficiency. Finally, the treatment without Mg²⁺ strongly suppressed the formation of large colony (mainly eight-celled colonies), whereas the algal growth rate was comparable to that in Mg²⁺ sufficient treatment. Despite the inhibition of colony formation, the time reaching the maximum number of cells per colony was not affected by the Mg²⁺ concentration, which generally took three days in all groups. Our results indicate that Mg²⁺ deficient/absent environments significantly reduced anti-grazing colony formation but not the algal growth, suggesting strong dependability of this morphological defensive trait to magnesium fluctuation in S. obliquus.
Показать больше [+] Меньше [-]Bed and suspended sediment-associated rare earth element concentrations and fluxes in a polluted Brazilian river system Полный текст
2018
da Silva, Yuri Jacques Agra Bezerra | do Nascimento, Clístenes Williams Araújo | da Silva, Ygor Jacques Agra Bezerra | Amorim, Fábio Farias | Cantalice, José Ramon Barros | Singh, V. P. (Vijay P.) | Collins, Adrian L.
Rare earth elements (REEs) have been recently recognized as emergent pollutants in rivers. However, data regarding REE fluxes in association with either bed or suspended are scarce. To address this knowledge gap, we determined the concentrations and fluxes of La, Ce, Pr, Nd, Sm, Eu, Gd, Yb, Lu, Dy, Er, Ho, Tb, and Tm in bed and suspended sediment samples of a representative polluted Brazilian River. Sediment-associated data on REEs were placed in the context of corresponding background concentrations in soils under natural conditions along the Ipojuca watershed. Light rare earth elements (LREEs) comprised more than 94% of the total REEs associated with bed and suspended sediments. Suspended sediments accounted for more than 95% of the total REE flux. The Ce and Nd fluxes of about 7 t year⁻¹ underscore the importance of including REEs in future estimations of global suspended sediment-associated element fluxes. In contrast, bedload often transported less than 0.0007 t year⁻¹ of each REE. The main sources of pollution in the Ipojuca River are anthropogenic, likely due to domestic effluent and waste water from industrial and agricultural operations—major causes of sediment-associated Gd transport in polluted streams.
Показать больше [+] Меньше [-]Facile synthesis of Fe3O4@MOF-100(Fe) magnetic microspheres for the adsorption of diclofenac sodium in aqueous solution Полный текст
2018
Zheng, Xiang | Wang, Jinlin | Xue, Xiaolong | Liu, Wanxia | Kong, Yadong | Cheng, Rong | Yuan, Donghai
In this research, the adsorptive removal of diclofenac sodium, one of the representative pharmaceuticals and personal care products, from aqueous solution using Fe₃O₄@MOF-100(Fe) magnetic microspheres was studied for the first time. The Fe₃O₄@MOF-100(Fe) microspheres exhibit strong magnetism and stability, which were observed as a core-shell structure. The maximum adsorption capacity of Fe₃O₄@MOF-100(Fe) for diclofenac sodium can reach 377.36 mg L⁻¹, which was higher than most of the adsorbents reported. The adsorption kinetics follows the pseudo-second-order kinetic equation. And the adsorption equilibrium of DCF can be described with Langmuir isotherm. In the cycle experiment, Fe₃O₄@MOF-100(Fe) material performed high adsorption efficiency for low-concentration diclofenac sodium solution, and the removal rate can still reach 80% after 5 cycles of adsorption without desorption. The mechanisms including electrostatic interaction, H-bond interaction, and π-π interaction that coexisted in the adsorption processes would be of benefit to enhance the adsorption capacity. The Fe₃O₄@MOF-100(Fe) magnetic microspheres offer exciting opportunities for further application.
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