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991.
992.
Cécile Vignal Muriel Pichavant Laurent Y. Alleman Madjid Djouina Florian Dingreville Esperanza Perdrix Christophe Waxin Adil Ouali Alami Corinne Gower-Rousseau Pierre Desreumaux Mathilde Body-Malapel 《Particle and fibre toxicology》2017,14(1):46
Background
Air pollution is a recognized aggravating factor for pulmonary diseases and has notably deleterious effects on asthma, bronchitis and pneumonia. Recent studies suggest that air pollution may also cause adverse effects in the gastrointestinal tract. Accumulating experimental evidence shows that immune responses in the pulmonary and intestinal mucosae are closely interrelated, and that gut-lung crosstalk controls pathophysiological processes such as responses to cigarette smoke and influenza virus infection. Our first aim was to collect urban coarse particulate matter (PM) and to characterize them for elemental content, gastric bioaccessibility, and oxidative potential; our second aim was to determine the short-term effects of urban coarse PM inhalation on pulmonary and colonic mucosae in mice, and to test the hypothesis that the well-known antioxidant N-acetyl-L-cysteine (NAC) reverses the effects of PM inhalation.Results
The collected PM had classical features of urban particles and possessed oxidative potential partly attributable to their metal fraction. Bioaccessibility study confirmed the high solubility of some metals at the gastric level. Male mice were exposed to urban coarse PM in a ventilated inhalation chamber for 15 days at a concentration relevant to episodic elevation peak of air pollution. Coarse PM inhalation induced systemic oxidative stress, recruited immune cells to the lung, and increased cytokine levels in the lung and colon. Concomitant oral administration of NAC reversed all the observed effects relative to the inhalation of coarse PM.Conclusions
Coarse PM-induced low-grade inflammation in the lung and colon is mediated by oxidative stress and deserves more investigation as potentiating factor for inflammatory diseases.993.
In the present work, the real and imaginary parts of permittivity of cubic modification silicon carbide (3C-SiC) nanoparticles are investigated before and after neutron irradiation. The real and imaginary parts of permittivity for the samples were studied in 0.1 Hz–2.5 MHz frequency and 100 K–400 K temperature ranges. The samples were continuously irradiated by neutron flux (2x10 13 n ?cm ?2 s ?1) up to 20 hours. The real and imaginary parts of permittivity were comparatively studied before and after irradiation. Neutron irradiation effects were studied with comparative analysis of non-irradiated samples. The increase in polarization was observed as a result of the increase in the impact period of neutron flux. All the mechanisms of the observed effects are given in the work. 相似文献
994.
Muhammad Imran Din Farhan Arshad Zaib Hussain Maria Mukhtar 《Nanoscale research letters》2017,12(1):638
Copper nanoparticles (CuNPs) are of great interest due to their extraordinary properties such as high surface-to-volume ratio, high yield strength, ductility, hardness, flexibility, and rigidity. CuNPs show catalytic, antibacterial, antioxidant, and antifungal activities along with cytotoxicity and anticancer properties in many different applications. Many physical and chemical methods have been used to synthesize nanoparticles including laser ablation, microwave-assisted process, sol-gel, co-precipitation, pulsed wire discharge, vacuum vapor deposition, high-energy irradiation, lithography, mechanical milling, photochemical reduction, electrochemistry, electrospray synthesis, hydrothermal reaction, microemulsion, and chemical reduction. Phytosynthesis of nanoparticles has been suggested as a valuable alternative to physical and chemical methods due to low cytotoxicity, economic prospects, environment-friendly, enhanced biocompatibility, and high antioxidant and antimicrobial activities. The review explains characterization techniques, their main role, limitations, and sensitivity used in the preparation of CuNPs. An overview of techniques used in the synthesis of CuNPs, synthesis procedure, reaction parameters which affect the properties of synthesized CuNPs, and a screening analysis which is used to identify phytochemicals in different plants is presented from the recent published literature which has been reviewed and summarized. Hypothetical mechanisms of reduction of the copper ion by quercetin, stabilization of copper nanoparticles by santin, antimicrobial activity, and reduction of 4-nitrophenol with diagrammatic illustrations are given. The main purpose of this review was to summarize the data of plants used for the synthesis of CuNPs and open a new pathway for researchers to investigate those plants which have not been used in the past. 相似文献
995.
Duplicate groundwater samples were collected from 104 monitoring wells (piezometers) from shallow aquifers underneath an industrial city in the Eastern Province of Saudi Arabia. Concentrations of Al, As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Ti, V, Zn, Ca, Mg, K, Na, Cl, SO4, alkalinity, salinity, total dissolved salts, and pH were determined in these samples. Analysis of variance showed significantly (p < 0.05) wide variations in the concentrations of the above parameters. The contour maps of metal concentrations indicated that these variations were related to important landmarks in the study area. The results of correlation analyses suggest that geographical as well as chemical factors may influence metal distribution in the groundwater samples. To investigate the geographical effects, the analytical data were normalized (element/Cl ratios were calculated) for chemical variability. As expected, contour mapping of the ratio data of element/Cl of Na, Ca, Mg, K, SO4, alkalinity, salinity, total dissolved salts, and Sr vary in a relatively small range and did not show a particular geographical trend. The groundwater sample from the industrial-dust area contained higher ratios between concentrations of Cl and Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, and Zn. These observations clearly suggest an extraneous contamination source, probably industrial dust, in the area. Another geographical area where metal (As, Cd, Cu, Mo, Ni, Ti,and V)/Cl ratios were found to be large was in the vicinity of an oil-refinery. Groundwater samples collected from the vicinity of a fertilizer plant and green-belt area contained relatively higher ratios of Al, Cd, Cr, Co, and Ni. The results of this study suggest that leachate from the industrial dust, leakage from the oil refinery and fertilizer plant, and drainage of irrigation water are some of the important pollution sources in the industrial city. 相似文献
996.
The aim of this work is to understand the bonding characteristics between various yarn structures and cement matrix which was studied by yarn pull out test. In this work, the effect of accelerated ageing under alkaline environment for different types of fibers i.e. Basalt, Polypropylene, Polyester, and Jute is studied in order to comparatively evaluate their weight loss and reduction of tensile strength. SEM images are also used for studying the morphology of alkali degraded fibers. Material characterization can also be done by FTIR, XRD, ICP, Zeta potential, and UV spectrometer. 相似文献
997.
Muhammad Shafqat Ali Muhammad Sagheer Aslam M. Saeed Mirza 《Structure and Infrastructure Engineering》2016,12(11):1381-1394
This paper deals with the development of a framework for assessment of sustainability of bridges, including related technical, economic, environmental and social issues. Sustainable infrastructure assets require diligent conception and design of facilities (with diligent choice of materials and construction techniques), high quality construction, and operations, involving routine maintenance, with optimised life-cycle performance and costs, and minimum impact on the environment over a stipulated long service life and beyond. Partial details of design, construction, maintenance and rehabilitation/renovation of the four versions of the 3-km long Victoria Bridge (1859, 1898, 1958 and 1988) are summarised, along with the partial details of design, construction, severe deterioration and subsequent rehabilitation of the nearly 6-km long, 6-lane Champlain Bridge. Sustainability of both bridges was assessed by implementing the proposed sustainability framework developed in this research programme, along with the use of the analytical hierarchy process which involved evaluation of pairwise comparison of the various categories to assist with evaluation of the sustainability scores. These scores indicate that all four forms of Victoria Bridge (1859, 1898, 1958 and 1988) are partially sustainable, or sustainable, while the Champlain Bridge is unsustainable. This framework can be appropriately adapted for assessing the sustainability of other infrastructure assets. 相似文献
998.
Jamali MK Kazi TG Arain MB Afridi HI Jalbani N Sarfraz RA Baig JA 《Journal of hazardous materials》2008,158(2-3):644-651
The aim of present study was to evaluate the variation in uptake of elements (As, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb and Zn) by different varieties of Sorghum bicolor L., plants grown in soil amended with untreated industrial waste water sewage sludge (SUIS), on same experimental plots. The power of chemometrics was also used in exploring the potential natural and/or anthropogenic sources responsible for elemental contents in different varieties of sorghum. Hierarchical cluster analysis was used to explore the different variety of sorghum grouping according to corresponding their SUIS samples as additional information to the output obtained by principal component analysis. Significant genotypic variation was detected in the fourteen elements concentrations in sorghum grains, indicating the possibility to reduce the concentration of toxic elements in grains through breeding approach. It was observed that high tolerance limit of toxic elements was observed in sorghum variety PARC-SV-1. 相似文献
999.
Nadeem R Hanif MA Shaheen F Perveen S Zafar MN Iqbal T 《Journal of hazardous materials》2008,150(2):335-342
The waste distillery sludge from sugar-cane industry was pretreated physically (boiled, heated and autoclaved) as well as chemically (HCl, H(2)SO(4), H(3)PO(4), NaOH, Ca(OH)(2), Al(OH)(3), C(6)H(6), HCHO, CH(3)OH and C1(2)H(25)OSO(3)Na (sodium dodecyl sulphate (SDS)) for assessing the comparative sorption capacity of untreated and modified distillery sludge for Pb(II) biosorption from aqueous solutions. Experiments were conducted in shake flasks on a batch basis to access the effect of different experimental parameters such as pH, biosorbent dosage, biosorbent size, initial Pb(II) concentration and contact time. The uptake capacity 'q' (mg/g) of untreated and pretreated distillery sludge was in following order: NaOH (51.29+/-1.21)>HCl (49.82+/-1.22)>HCHO (49.56+/-1.14)>H(2)SO(4) (47.71+/-1.20)>HgCl(2) (45.32+/-1.06)>Ca(OH)(2) (44.01+/-1.18)>MeOH (43.73+/-1.23)>C(6)H(6) (42.72+/-1.19)>H(3)PO(4) (42.01+/-1.17)>SDS (40.87+/-1.27)>autoclaved (40.23+/-1.24)>Boiled (39.95+/-1.19)>heated (38.87+/-1.32)>Al (OH)(3) (38.30+/-1.14)>untreated (37.76+/-1.21). In further parameter studies, the optimized biosorbent size was 0.250 mm at pH 5 and best dose was 0.05 g of biosorbent. The applicability of the Langmuir and Freundlich models for sorption process was tested and best fitted model was Langmuir with the coefficient of determination (R(2)) value, 0.97, the process followed second order kinetic mechanism. 相似文献
1000.
Hazardous impact of toxic metals on tobacco leaves grown in contaminated soil by ultrasonic assisted pseudo-digestion: multivariate study 总被引:1,自引:0,他引:1
Arain MB Kazi TG Jamali MK Jalbani N Afridi HI Kandhro GA Ansari R Sarfraz RA 《Journal of hazardous materials》2008,155(1-2):216-224
Tobacco leaves (Nicotiana tabacum L.), agricultural soil and pollute irrigated lake water samples were collected during 2005–2006 and analyzed for Cd and Ni by electrothermal atomic absorption spectrometry (ETAAS). A simple and efficient procedure was investigated for the complete decomposition of tobacco leaves using ultrasonic assisted acid pseudo-digestion method (UPDM). A Plackett–Burman experimental design was used as a multivariate strategy for the evaluation of seven factors/variables at once, while central composite were used to found optimum values of significant variables. The accuracy of the proposed methods was assessed by analyzing certified reference (CRM); Virginia tobacco leaves (CTA-VTL-2). The results being compared with those obtained by conventional wet acid digestion method. The result obtained by optimized method showed good agreement with the certified values and sufficiently high recovery 97.8 and 98.7% for Cd and Ni, respectively. Under optimal conditions, the detection limits (3σ) were evaluated to be 0.019 μg g−1 for Cd and 0.37 μg g−1 for Ni. The proposed method was successfully applied to the determination of Cd and Ni in raw, processed tobacco and different branded cigarettes samples. 相似文献