Academic literature on the topic 'Cd cr in s'
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Journal articles on the topic "Cd cr in s"
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Yang, Shipeng, Siwei Peng, Chunhui Zhang, Xuwen He, and Yaqi Cai. "Synthesis of CdxZn1−xS@MIL-101(Cr) Composite Catalysts for the Photodegradation of Methylene Blue." Nano 13, no. 10 (October 2018): 1850118. http://dx.doi.org/10.1142/s1793292018501187.
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Nanoparticles of the semiconductor catalyst CdxZn[Formula: see text]S were embedded into the metal organic framework MIL-101(Cr) to obtain CdxZn[Formula: see text]S@MIL-101(Cr) nanocomposites. These materials not only possess high surface areas and mesopores but also show good utilization of light energy. The ultraviolet-visible diffuse reflectance patterns of CdxZn[Formula: see text]S@MIL-101(Cr) nanocomposites showed that Cd[Formula: see text]Zn[Formula: see text]S@MIL-101(Cr) possessed good visible light response ability among the synthesized nanocomposites. The photocatalytic performance of the CdxZn[Formula: see text]S@MIL-101(Cr) nanocomposites were tested via degradation and mineralization of methylene blue in neutral water solution under light irradiation using a 300W xenon lamp. As a result, using Cd[Formula: see text]Zn[Formula: see text]S@MIL-101(Cr) as a catalyst, 99.2% of methylene blue was mineralized within 30[Formula: see text]min. Due to the synergistic effect of adsorption by the MIL-101(Cr) component and photocatalytic degradation provided by the Cd[Formula: see text]Zn[Formula: see text]S component, the Cd[Formula: see text]Zn[Formula: see text]S@MIL-101(Cr) catalyst displayed superior photocatalytic performance relative to Cd[Formula: see text]Zn[Formula: see text]S and MIL-101(Cr). Furthermore, Cd[Formula: see text]Zn[Formula: see text]S@MIL-101(Cr) possessed excellent stability during photodegradation and exhibited good reusability. The remarkable photocatalytic performance of Cd[Formula: see text]Zn[Formula: see text]S@MIL-101(Cr) is likely due to the effective transfer of electrons and holes at the heterojunction interfaces.
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Cai, Kui, Chang Li, Zefeng Song, Xin Gao, and Moxin Wu. "Pollution and Health Risk Assessment of Carcinogenic Elements As, Cd, and Cr in Multiple Media—A Case of a Sustainable Farming Area in China." Sustainability 11, no. 19 (September 23, 2019): 5208. http://dx.doi.org/10.3390/su11195208.
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The high concentrations of trace elements in the environment, especially the carcinogenic elements Cr, Cd, and As, in populated areas can lead to an increased non-carcinogenic risk and carcinogenic risk in humans via the effective exposure pathways (inhalation and dermal contact). In this study, the concentrations of the trace elements Cd, Cr, and As in four media were comprehensively evaluated by collecting samples from atmospheric precipitates (A), wheat (W), soil (S), and groundwater (G) in the agricultural plain. This study not only considers the health risk level, but also focuses on the relationship between soil properties and the soil–wheat system. First, according to the results of the analysis, the concentration of carcinogenic elements in atmospheric precipitates was higher than that in other media. The sequence follows the order A > S > W > G. Moreover, the input flux of A was at a relatively higher level (determined via an input flux calculation) than other farming areas. Second, the pollution of Cr, Cd, and As in A and S were analyzed using the geoaccumulation method, and the level of Cd reached mild to moderate pollution. In addition, it was found that the bioaccumulation factors (BAFs) of Cd were much higher than those of As and Cr in the soil–wheat system. Furthermore, it was found that the negative relationship between BAFs and pH, CEC (cation exchange capacity), Corg (soil organic carbon), and clay was significant. Lastly, the hazard quotient (HQ) of the non-carcinogenic risk and carcinogenic risk (CR) of the three elements in multiple media were calculated using the health risk model. The HQ results showed that the total non-carcinogenic risk index (HI) of Cd, As, and Cr in the multiple-media did not exceed the risk limit (1.00), and there was no significant risk to the locally exposed population. However, the total carcinogenic risk index (TCR) indicated that the risk index of Cr, As and Cd in multiple media exceeded the safety index range (≈10−6–10−4), and the three elements posed a significant carcinogenic risk to local residents via the main pathways. In terms of individual elements, the risk of cancer was highest via the ingestion of the carcinogenic element Cd in G and W.
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Zeng, Jie, Guilin Han, Qixin Wu, and Yang Tang. "Heavy Metals in Suspended Particulate Matter of the Zhujiang River, Southwest China: Contents, Sources, and Health Risks." International Journal of Environmental Research and Public Health 16, no. 10 (May 24, 2019): 1843. http://dx.doi.org/10.3390/ijerph16101843.
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To investigate the abundance, water/particle interaction behavior, sources, and potential risk of heavy metals in suspended particulate matter (SPM), a total of 22 SPM samples were collected from the Zhujiang River, Southwest China, in July 2014 (wet season). Nine heavy metal(loid)s (V, Cr, Mn, Ni, Cu, Zn, As, Cd and Pb) in SPM were detected. The results show that the selected heavy metal(loid)s in SPM appear in the following order: Mn (982.4 mg kg−1) > Zn (186.8 mg kg−1) > V (143.6 mg kg−1) > Cr (129.1 mg kg−1) > As (116.8 mg kg−1) > Cu (44.1 mg kg−1) > Ni (39.9 mg kg−1) > Pb (38.1 mg kg−1) > Cd (3.8 mg kg−1). Furthermore, both the enrichment factor (EF) and geo-accumulation index (Igeo) indicate that SPM is extremely enriched in metal(loid)s of Cd and As, while SPM is slightly enriched, or not enriched, in other heavy metals. According to the toxic risk index (TRI) and hazard index (HI), arsenic accounts for the majority of the SPM toxicity (TRI = 8, 48.3 ± 10.4%) and causes the primary health risk (HI > 1), and the potential risks of V and Cr are also not negligible. By applying a correlation matrix and principal component analysis (PCA), three principal components (PC) were identified and accounted for 79.19% of the total variance. PC 1 (V, Cr, Mn, Ni, Cu, and Pb) is controlled by natural origins. PC 2 (As and Cd) is mainly contributed by anthropogenic origins in the basin. PC 3 (Zn) can be attributed to mixed sources of natural and anthropogenic origins. Moreover, all the partition coefficients (lgKd) exceeded 2.9 (arithmetical mean value order: Mn > Pb > Cd > V ≈ Cu > Cr ≈ Ni), indicating the powerful adsorptive ability of SPM for these heavy metal(loid)s during water/particle interaction.
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Cai, Kui, Minjie Zhang, Yanqiu Yu, and Kangjoo Kim. "Pollution, Source, and Relationship of Trace Metal(loid)s in Soil-Wheat System in Hebei Plain, Northern China." Agronomy 9, no. 7 (July 17, 2019): 391. http://dx.doi.org/10.3390/agronomy9070391.
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To study the complex migration and transformation of trace metal(loid)s in a soil–wheat system, 225 pairs of surface soil and wheat samples were collected from the Taihang Mountains front plain, Hebei Province, northern China. The concentrations and pools (F1, water-soluble; F2, exchangeable; F3, carbonate-bound; F4, humic acid-bound; F5, Fe–Mn oxide-bound; F6, organic matter-bound; and F7, residual) of Cu, Pb, Zn, Cr, Ni, Cd, and Hg, and the soil properties of the samples were analyzed. The sum of the F1, F2, F3, and F4 proportions of Cd was higher than that of the other trace metal(loid)s, implying that Cd has greater mobility. We found a significant correlation (p < 0.01) between pools of trace metal(loid)s and the corresponding elements in wheat and a significant correlation (p < 0.01) between pools of trace metal(loid)s and pH, cation exchange capacity, clay, and total organic carbon. The results of principle component analysis (PCA)indicated that Cr, Ni and As mainly come from natural sources and Cu, Pb, Zn, and Cd from mixed groups related to farming and industry, Hg come from the coal burning. In addition, the total target hazard quotients showed the presence of harmful levels of trace metal(loid)s in wheat.
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Liang, Baocui, Xiao Qian, Shitao Peng, Xinhui Liu, Lili Bai, Baoshan Cui, and Junhong Bai. "Speciation Variation and Comprehensive Risk Assessment of Metal(loid)s in Surface Sediments of Intertidal Zones." International Journal of Environmental Research and Public Health 15, no. 10 (September 27, 2018): 2125. http://dx.doi.org/10.3390/ijerph15102125.
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Speciation variation and comprehensive risk assessment of metal(loid)s (As, Cd, Cr, Cu, Mn, Ni, Pb and Zn) were investigated in surface sediments from the intertidal zones of the Yellow River Delta, China. Results showed that only the concentrations of As, Cd and Pb were significantly different between April and September (p < 0.01). In April, the residual fraction (F4) was predominant for As, Cr, Cu, Ni and Zn. However, the exchangeable and carbonate-associated fraction (F1) was dominant for Cd averaging 49.14% indicating a high environmental risk. In September, the F4 fraction was predominant and the F1 fraction was very low for most metal(loid)s except Cd and Mn. The geo-accumulation index (Igeo), the F1 fraction and potential ecological risk index (PERI) of most metal(loid)s were relatively low in surface sediments for both seasons. But Pb, As and Ni were between the threshold effect level (TEL)and the probable effect level (PEL) for 66.67%, 83.33% and 91.67% in April and As and Ni were between TEL and PEL for 41.67% and 91.67%, which indicated that the concentration of them was likely to occasionally exhibit adverse effects on the ecosystem. Although the Igeo, the F1 fraction or PERI of Cd in both seasons was higher at some sites, the results of sediment quality guidelines (SQGs) indicated that the biological effects of Cd were rarely observed in the studied area.
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Gokhman, Aleksandr R., Andreas Ulbricht, Uwe Birkenheuer, and Frank Bergner. "Cluster Dynamics Study of Neutron Irradiation Induced Defects in Fe-12.5at%Cr Alloy." Solid State Phenomena 172-174 (June 2011): 449–57. http://dx.doi.org/10.4028/www.scientific.net/ssp.172-174.449.
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Cluster dynamics (CD) is used to study the evolution of the size distributions of vacancy clusters (VC), self-interstitial atom (SIA) clusters(SIAC) and Cr precipitates in neutron irradiated Fe-12.5at%Cr alloys at T = 573 K with irradiation doses up to 12 dpa and a flux of 140 ndpa/s. Transmission electron microscopy (TEM) and small angle neutron scattering (SANS) data on the defect structure of this material irradiated at doses of 0.6 and 1.5 dpa are used to calibrate the model. A saturation behavior was found by CD for the free vacancy and free SIA concentrations as well as for the number density of the SIAC and the volume fraction of the Cr precipitates for neutron exposures above 0.006 dpa. The CD simulations also indicate the presence of VC with radii less than 0.5 nm and a strong SIAC peak with a mean diameter of about 0.5 nm, both invisible in SANS and TEM experiments. A specific surface tension of about 0.028 J/m2 between the a matrix and the Cr-rich a' precipitate was found as best fit value for reproducing the long-term Cr evolution in the irradiated Fe-12.5%Cr alloys observed by SANS.
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Ahmed, Abu Tweb Abu, Suman Mandal, Didarul Alam Chowdhury, Abu Rayhan M. Tareq, and M. Mizanur Rahman. "Bioaccumulation of Some Heavy Metals in Ayre Fish (Sperata Aor Hamilton, 1822), Sediment and Water of Dhaleshwari River in Dry Season." Bangladesh Journal of Zoology 40, no. 1 (December 10, 2012): 147–53. http://dx.doi.org/10.3329/bjz.v40i1.12904.
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The present study was carried out to determine the level of bioaccumulation of some heavy metals in a freshwater fish Ayre (Sperata aor Hamilton, 1822) collected from Rajfulbaria (23°48?56.36? N and 90°14?54.04? E) of Dhaleshwari river. Four heavy metals, namely chromium (Cr), copper (Cu), lead (Pb), and cadmium (Cd) were selected for this study. Metal concentrations were determined by Flame Atomic Absorption Spectrophotometer after nitric acid digestion of samples. The concentrations of accumulated heavy metals in fish were also compared with the concentrations of metals in the sediments and waters of that river. The level of bioaccumulations in different organs of S. aor were determined separately and compared among them. Average bioaccumulation levels in S. aor were Cr: 1.458 mg/kg, Cu: 31.500 mg/kg, Pb: 18.776 mg/kg and Cd: 0.487 mg/kg of dry weight. The levels of heavy metals in sediments were Cr: 27.393 mg/kg, Cu: 37.450 mg/kg, Pb: 15.797 mg/kg and Cd: 2.083 mg/kg, and in water were Cr: 0.130 ppm, Cu: 0.000 ppm, Pb: 0.201 ppm and Cd: 0.001 ppm.The bioaccumulation of these four heavy metals in fish organs, sediment and water samples were also compared with FAO approved standard levels and other related studies, and found that the levels of bioaccumulation in the Dhaleshwari river exceeded all the standard levels. DOI: http://dx.doi.org/10.3329/bjz.v40i1.12904 Bangladesh J. Zool. 40(1):147-153, 2012
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Sultana, N., H. Muktadir, MAH Chowdhury, and MA Baten. "Assessment of the Quality of Industrial Wastewater in Three Metropolitan Cities in Bangladesh." Journal of Environmental Science and Natural Resources 9, no. 2 (April 14, 2017): 21–25. http://dx.doi.org/10.3329/jesnr.v9i2.32145.
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This study was conducted to assess the quality of different industrial wastewater. Some physicochemical parameters viz., pH, EC, TDS, Na+, K+, Ca++, Mg++, CO32-, HCO3-, Cl-, SO42-, PO43- including heavy metal contents like Pb, Cd, Ni, Cr, As, Zn and Cu concentration from collected wastewater samples were analyzed. Atomic Absorption Spectrophotometer was used for analyzing the heavy metals in the wastewater samples. The results revealed that, the values of pH, EC, TDS ranged between 6.44-9.0, 471-4307 ?S cm-1, 1952-5209 mg L-1, respectively. The higher mean concentrations of Na+, K+, Ca++, Mg++, CO3-, HCO3-, Cl-, SO42-, PO43- were 1407.8, 27.9, 69.9, 76.6, 2.7, 11.7, 1688, 76.6, 6.1 mg L-1, respectively. The mean concentration of Cd, Ni, Cr, Zn, and Cu was 0.17, 0.87, 85.73, 0.80, and 1.56 mg L-1, respectively. Among trace elements Ni and Cd, Zn and Cd, Zn and Cr showed a positive relationship. To avoid the harmful effects of wastewater on environment it is imperative to treat industrial effluents before discharge into open environment.J. Environ. Sci. & Natural Resources, 9(2): 21-25 2016
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Šestinová, Oľga, Jozef Hančuľák, and Tomislav Špaldon. "Earthworms as useful bioindicator of soils contamination around Košice city, Slovakia." Nova Biotechnologica et Chimica 18, no. 1 (June 1, 2019): 10–17. http://dx.doi.org/10.2478/nbec-2019-0002.
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Abstract This study was conducted to investigate heavy metals bioaccumulation in industrialized soils in surrounding of Košice city (Slovakia), using earthworms. In the present research, we used ecotoxicity tests with Dendrobaena veneta (7 and 28-day bioassays) to infer about potential toxic risks to the agricultural (A) and permanent grass vegetation (PGV) of soils around the plant U. S. Steel Košice. The total Fe, Cu, Zn, Pb, Cd, Cr and As contents and eco-toxicological tests of industrialized soils from the Košice area were performed for 12 sampling sites in years 2016 – 2017. An influence of the sampling sites distance from the largest steel producer plant on the total concentrations of heavy metals was determined for Fe, Cd, Cr and As. It was found that earthworms (Dendrobaena veneta) in some cases caused a decrease of metals concentration in contaminated soils, the largest metal concentration differences were recorded in the samples PGV (4) U. S. Steel-plant-main gate. The results of the bioaccumulation factors of heavy metals in D. veneta (BAFs/7-28 d) are < 1 for the studied metals order in the sequence: Cr < Fe < Pb < Cu < As and > 1 for Zn > Cd.
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Taş, Elif Çağrı, and Uğur Sunlu. "Heavy Metal Concentrations in Razor Clam (Solen marginatus, Pulteney, 1799) and Sediments from Izmir Bay, Aegean Sea, Turkey." Turkish Journal of Agriculture - Food Science and Technology 7, no. 2 (February 24, 2019): 306. http://dx.doi.org/10.24925/turjaf.v7i2.306-313.2284.
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This study was carried out to determine the concentrations of some heavy metals (Cd, Cu, Pb, Zn, Cr and Fe) in Solen marginatus (Pulteney, 1799) and sediments in the middle region of Izmir Bay. Metal concentrations in S. marginatus vary in the one-year period between summer 2005 and summer 2006. The order of accumulation of metal concentrates in soft tissue of razor clam was determined as Cd < Pb < Cr< Cu < Zn < Fe. Metal accumulations in the soft tissue of S. marginatus were compared with Provisional Tolerable Weakly Intakes (PTWI) and Provisional Tolerable Daily Intakes (PTDI) for human consumption. The results show that the maximum concentrations of metals were markedly below the limits of the FAO (Food and Agriculture Organization), WHO (World Health Organization) and TFC (Turkish Food Codex) for human consumption. The order of the metal concentrations detected in the sediment samples was Cd < Pb < Cu< Cr < Zn < Fe. In this study, the maximum heavy metal values determined in the sediment are below the criteria values of the stated for international sediment quality guidelines in the NOAA (The National Oceanic and Atmospheric Administration), OMEE (The Ministry of Environment and Energy of Ontario), ANZECC (The Australia and New Zealand Environmental on Conservation Council), CCME (The Canadian Council of Ministers of Environment). There was a statistically significant but weak correlation between concentrations of Cu and Cr in sediment and S. marginatus. The significant correlations have shown that Solen species can be used as a bioindicator species, such as mussels due to their ability to accumulate heavy metals.
Dissertations / Theses on the topic "Cd cr in s"
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Bruneau, Audrey. "Immunotoxicité des nanoparticules de Cd/S, Cd/Te et d’Ag sur des espèces modèles." Brest, 2011. http://www.theses.fr/2011BRES2015.
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A l'heure actuelle, l'usage des nanoparticules (NP5) est de plus en plus médiatisé. Elles sont maintenant utilisées à grande échelle dans de nombreux domaines, L’objectif principal de cette thèse était donc d’évaluer l’immunotoxicité des NPs de Cd/S, Cd/Te et d’Ag sur 4 espèces modèles: l’humain, la souris, la truite arc en ciel et la moule bleue, Dans le cadre de ces travaux, nous avons défini quatre sou objectifs: 1) déterminer l’impact des NPs sur différentes cellules et systèmes immunitaires 2) évaluer les facteurs influençant la toxicité des NPs; 3) identifier les atteintes mécanistiques de la réponse immunitaire 4) établir la toxicité des NPs en fonction des stress environnementaux. Les résultats du projet ont démontrés que les NPs induisent des altérations des performances du système immunitaire, selon les espèces. De plus, nous avons aussi démontré que cette toxicité était influencée par la chimie, la nature du métal la taille de la NP. Nos résultats ont aussi indiqué une action mécanistique des NPs. Des phénomènes de stress oxydatif, de production d métallothionéines, d’apoptose et de nécrose ont été observés. Enfin des études in situ, en France et au Québec, ont démontré que des organismes déjà sensibilisés par leur milieu de vie sont encore plus sensibles à une exposition aux NPs. Ce projet a contribué à enrichir les connaissances sur la toxicité des NPs selon différents modèles d’études. Ceci a permis d’évaluer la sensïbilité de chaque espèce et les actions mécanistiques des NPs. Les résultats concemant la sensibilité des différents modéles d’animaux pourront étre utilisés dans les prochaines études de risquesActually, the usage of nanoparticles (NPs) is more and more mediatized. They are used on a large scale in numerous domains. The mail objective of this thesis was to estimate the immunotoxicity of the NPs of Cd/S, Cd/Te and of Ag on 4 model species: human, mouse, rainbow trout and blue mussel. For the project, we defined four sub-objectives: 1) determine the impact of the NPs on various cells and immune systems; 2) estimate factors influencing the toxicity of the NPs; 3) identify mechanistic achievements of the immunizing answer 4 establish the toxicity of the NPs according to environmental stress. The project results demonstrate that the NPs induced immune system performance changes, according study species. Furthermore, we also demonstrated that this toxicity was influenced by the chemistry, the’ nature of the metal and NPs size. Our results also indicated mechanistic impacts of NPs on immune cells. Oxydative stress phenomena, metallothioneines production, apoptosis and necrosis were observed. Finally in situ studies, in France and in Quebec, demonstrated that organisms already sensitized by their life environment are more sensitive to additional exposure of NPs. This project contributed to improve the knowledge on NPs toxicity according to different models species. This allowed to estimate the sensibility of every species on the NPs toxicity mechanism. The results concerning could be used in the future studies of risk assessment
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Peterson, Karin E. "The role of secondary signaling in experimental autoimmune thyroiditis." free to MU campus, to others for purchase, 1998. http://wwwlib.umi.com/cr/mo/fullcit?p9904865.
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Pouget, Stéphanie. "Contribution à l'étude de l'influence de la dilution sur les propriétés magnétiques de composés isolants frustrés." Toulouse, INSA, 1993. http://www.theses.fr/1993ISAT0039.
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Nous avons principalement etudie le systeme ferromagnetique heisenberg-3d frustre cdcr#2#(#1##x#)in#2#xs#4, dans la limite des faibles dilutions x. La structure des phases ferromagnetiques et verre de spin reentrante a ete exploree par diffraction de neutrons et mesures d'aimantation macroscopiques. Les resultats s'interpretent dans le cadre d'un modele inhomogene du systeme de spins. Par diffusion de neutrons aux petits angles, spectrometries trois-axes et d'echo de spin, nous avons caracterise le comportement critique statique et dynamique des composes x=0 et 0. 05. Cette etude a revele la pertinence de la dilution et ainsi un des effets de la frustration qui est de porter le systeme dans la limite des forts desordres. Nos resultats suggerent l'existence de deux comportements statiques differents du compose cdcr#1#. #9in#0#. #1s#4, de part et d'autre de t#c, concernant la dynamique, nous avons mis en evidence une evolution non monotone du temps de relaxation en fonction du moment transfere, pour des valeurs de celui-ci tres inferieures a l'inverse de la longueur de correlation, et voisines de l'inverse de la distance moyenne entre impuretes in#3#+. La derniere partie de ce travail est consacree au systeme frustre ising-3d fe#1##xmg#xbr#2. Les mesures de la dispersion des ondes de spin pour differentes directions du moment transfere nous ont permis de preciser le modele des interactions d'echange pour le compose febr#2. Nous avons etudie la transition de phase para-antiferromagnetique pour les deux valeurs de la dilution x=0 et 0. 1. Les resultats sont interpretes dans le cadre d'une theorie classique de champ moyen
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Freitas, Josias Coriolano de. "Avaliação da Alocasia macrorhiza como Fitorremediadora dos metais Cd, Cr, Cu, Ni, Pb, Zn." Universidade Federal do Amazonas, 2009. http://tede.ufam.edu.br/handle/tede/3108.
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Previous issue date: 2009-07-01Fundação de Amparo à Pesquisa do Estado do Amazonas
For more then three centuries plants has been used for decontaminating soils and water with quimical products. However, recently this practice is being intensificated, due to low costs and mainly for the facilities that these plants may be used in situ. The phytoremediation technique reached worldwide importance due to the technology which extract and/or immobilize organic and inorganic contaminates. The main objective of this Thesis is to study for the first time the absorption capacity of heavy metals such as Cd, Pb, Cr, Ni, Zn and Cu by specie Alocasia macrorhiza arranged in the ciliate diversity rain forest located in the Amazon region and in the Industrial District, which the contamination is considered to be high and test concentrations of 3, 6, 9, 12 and 15 mmol Kg-1 of EDTA on bioavailability of these metals on soils. In this study, were collected plants in six different places in Manaus, capital city of the State of Amazonas-Brazil and after these plants have been collected, they were separated in root, stalk and leaf. The heavy metals concentrations were determined by flame atomic absorption spectrophotometry. For the statistical analysis were used the non-parametric for Kruskal-Wallis and Mann-Whitney tests. The test demonstrated that all metals were absorpt the same way independently the region were the plant was collected. Pb presented the highest concentration absorbed by the plant following Cr > Cd> Cu> Ni> Zn metals. Are findings also revealed that the absorption metals sequence levels repeated in other parts of the plant. Cr was the only metal that not presented significant variation in parts of the plant, neither in the collected area. EDTA concentrations that had better assimilation of Pb extracted by the in situ plant were between 3 and 15 g Kg-1.
O uso de plantas para descontaminação do solo e água contaminadas por produtos químicos é utilizado há mais de três séculos. A fitorremediação alcançou importância mundial por ser uma tecnologia que extrai e/ou imobiliza contaminantes de origem orgânica e inorgânica. Neste sentido, este trabalho teve como objetivo avaliar pela primeira vez a capacidade de absorção do metais Cd, Pb, Cr, Ni, Zn e Cu pela Alocasia macrorhiza que compõe a flora de algumas matas ciliares da cidade de Manaus, cujo nível de contaminação são elevados e avaliar as concentrações 3, 6, 9, 12, 15 mmol kg−1 de EDTA na biodisponibilidade desses metais nos solos estudados. Para esse estudo as plantas coletadas foram divididas em raiz, caule e folha para extração dos metais. As concentrações dos metais pesados foram determinados pela espectrometria de absorção atômica de chama, e os resultados analisados pelo teste não-paramétrico por Kruskal-Wallis e Mann-Whitney e análise do componente principal 1 e 2. Os testes mostraram que todos os metais foram absorvidos da mesma forma independentemente do local. O Pb foi o metal que apresentou maior concentração na planta seguindo por Cr > Cd > Cu> Ni > Zn, seqüência que se repete nas outras partes da planta. O Cr foi o único metal que não apresentou variação significativa nas partes da planta e nem nos locais de coletas. As concentrações de EDTA mostram a mesma distribuição de Pb e Cr em in situcomparando com a raiz da planta.
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Fioroto, Alexandre Minami. "Avaliação da mobilidade e biocessibilidade de As, Cd, Cr e Pb em fertilizantes minerais." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-12042018-092931/.
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Fertilizantes minerais derivados de rochas fosfáticas podem ser uma fonte de contaminantes, como As, Cd, Cr, Pb e Hg. Além disso, resíduos de indústrias metalúrgicas e químicas podem ser adicionados à composição de fertilizantes para fornecer micronutrientes, atuando como uma fonte adicional de contaminantes. Desta forma, o controle de qualidade de fertilizantes e matérias-primas é importante para evitar danos ao meio ambiente e garantir uma produção segura de alimentos. Neste trabalho, procedimentos de digestão assistida por radiação micro-ondas de um fertilizante mineral formulado e uma mistura de micronutrientes foram desenvolvidos para a determinação simultânea de Al, As, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, P, Pb e Zn por ICP OES, avaliando doze misturas ácidas contendo HNO3, HCl, H3PO4, HF e H3BO3. A PCA foi aplicada para auxiliar a escolha de três procedimentos de digestão que exibiram os resultados com maior exatidão. O protocolo de extração sequencial do BCR foi aplicado para investigar a mobilidade e a bioacessibilidade dos elementos. As e Cd foram extraídos principalmente na primeira etapa, portanto estão fracamente ligados à matriz e, consequentemente, estão mais móveis e bioacessíveis. O Cr permaneceu quase que completamente na fração residual. O Pb apresentou maior mobilidade e bioacessibilidade na mistura de micronutrientes do que no fertilizante mineral formulado, possivelmente, devido a precipitação de Pb3(PO4)2, causado pela alta concentração de P no fertilizante. Os nutrientes (P, Ca, Mg, Cu, Mn e Zn) apresentaram boa bioacessibilidade, exceto Fe, que permaneceu quase totalmente na fração residual. Além disso, análises por DRX e MEV-EDS foram empregadas para caracterizar os resíduos sólidos das extrações, mostrando que os elementos podem ser cobertos por estruturas cristalinas (quartzo), que inibem a sua lixiviação e os tornam menos móveis e bioacessíveis. Um sistema de extração em fluxo foi proposto para avaliar a mobilidade e a bioacessibilidade de As, Cd, Cr e Pb em fertilizantes, que foi mais eficiente que os procedimentos em batelada, pois o sistema em fluxo simula a constante lixiviação que ocorre no solo, com a infiltração das águas de chuva ou irrigação das plantações. Além disso, essas análises foram realizadas no modo transiente do ICP OES, que permitiu avaliar a cinética de extração dos elementos. O procedimento foi empregado para misturas de fertilizante com solo, onde foram observados sinais que demoravam a retornar a linha base, demonstrando a interação dos elementos com a matriz do solo. Um estudo de especiação por XANES também foi realizado e possibilitou a identificação das espécies As(V), Fe2-xCrxO3 e PbCl2 no fertilizante e na mistura de micronutrientes. Ensaios realizados com brotos de milho foram realizados para avaliar a translocação de As, Cd, Cr e Pb. Além disso, a partir das análises de especiação de As por HPLC-ICP-MS, foi observado que exsudatos promoveram a redução do As(V) para As(III), sendo esta a espécie absorvida e translocada pela planta.Mineral fertilizers derived from phosphate rocks can be a source of contaminants, such as As, Cd, Cr, Pb and Hg. In addition, metallurgical and chemical industry residues can be added to the fertilizer composition to provide micronutrients, acting as an additional source of contaminants. In this way, the quality control of fertilizers and raw materials is important to avoid damages to the environment and ensure a safe food production. In this work, microwave-assisted digestion procedures of a formulated mineral fertilizer and a mixture of micronutrients were developed for simultaneous determination of Al, As, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, P, Pb and Zn by ICP OES, evaluating twelve acidic mixtures containing HNO3, HCl, H3PO4, HF and H3BO3. PCA was applied to assist in the choice of three digestion procedures that exhibited the more accurate results more. The BCR sequential extraction protocol was applied to investigate the elements mobility and bioaccessibility. As and Cd were extracted mainly in the first step, thus they are weakly bound to the matrix and, consequently, are more mobile and bioaccessible. The Cr remained almost completely in the residual fraction. Pb presented higher mobility and bioaccessibility in the mixture of micronutrients than in the formulated mineral fertilizer, possibly due to the precipitation of Pb3(PO4)2 caused by the high concentration of P in the fertilizer. The nutrients (P, Ca, Mg, Cu, Mn and Zn) presented good bioaccessibility, except Fe, which remained almost totally in the residual fraction. In addition, XRD and SEM-EDS analyzes were employed to characterize the solid residue from extractions, showing that the elements can be covered by crystalline structures (quartz), which inhibit their leaching and make them less mobile and bioaccessible. A flow extraction system was proposed to evaluate the mobility and bioaccessibility of As, Cd, Cr and Pb in fertilizers, which was more efficient than batch procedures, because the flow system simulates the constant leaching occurring in soil, with infiltration of rainwater or irrigation of plantations. In addition, these analyses were performed in the transient mode of ICP OES, which allowed evaluating the kinetics of elements extraction. The procedure was applied to mixtures of fertilizer with soil, where a slow return to baseline of signal was observed, demonstrating the interaction of the elements with the soil matrix. XANES speciation study was also carried and allowed the identification of the species As(V), Fe2-xCrxO3 and PbCl2 in the fertilizer and mixture of micronutrients samples. Bioassays performed with maize sprouts were carried out to evaluate the translocation of As, Cd, Cr and Pb. In addition, from As speciation analysis by HPLC-ICP-MS, it was observed that exudates promoted the reduction of As (V) to As (III), being this the species absorbed and translocated by the plant.
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Mendes, Izabela Aparecida da Silva. "Adsorção individual de Cd, Cr, Cu e Pb em solos da bacia sedimentar Amazônica." Universidade Federal de Viçosa, 2016. http://www.locus.ufv.br/handle/123456789/10348.
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O solo, a depender de suas características físicas, químicas e mineralógicas, pode apresentar uma elevada capacidade de reter íons e moléculas e pode assim funcionar como um excelente meio para adsorver metais pesados. No bioma Amazônia encontra-se a maior floresta tropical do mundo, e o solo é um dos responsáveis pela sustentação da vegetação nessa região. A interação solo-vegetação nesta região confere comportamento diferente de outros solos do Brasil. Entende-se que estudos de adsorção de metais pesados em solos do Amazonas contribuirão para a compreensão do comportamento destes elementos naqueles solos. Parte-se do pressuposto que solos mais oxídicos e de textura mais argilosa, ricos em minerais 1:1, apresentarão grande capacidade para adsorver metais pesados, enquanto que a adsorção destes metais será menor em solos ricos em minerais 2:1. Assim, o presente trabalho tem como objetivos: conduzir ensaios de adsorção individual para os metais pesados Cd, Cr, Cu e Pb em solos representativos da bacia sedimentar Amazônica com composições mineralógicas distintas; avaliar o comportamento individual dos metais pesados frente aos solos estudados; avaliar qual dos modelos de isotermas de Langmuir e Freundlich melhor descreve a adsorção de metais pesados nos solos estudados; determinar a capacidade máxima de adsorção (CMA) dos metais pesados nos solos e; identificar a relação entre os parâmetros das isotermas e os atributos dos solos. Os pontos de amostragem foram selecionados de acordo com a representatividade e distribuição dos solos na bacia sedimentar Amazônica, sendo as amostras coletadas em áreas não antropizadas. As classes de solo Latossolo Amarelo; Argissolo Amarelo; Neossolo Quartzarênico Hidromórfico; Neossolo Quartzarênico Órtico; Neossolo Flúvico; Gleissolo; Terra Preta de Índio; Plintossolo e Espodossolo. Os ensaios de adsorção foram baseados no princípio de que quantidades conhecidas de solo e de soluto em solução são colocadas em contato sob agitação até que o sistema alcance o equilíbrio. A concentração dos metais em solução, após o equilíbrio, foi realizada por Espectrofotometro de Absorção Atômica. Os dados foram ajustados aos modelos de regressão não linear de Langmuir e Freundlich, de forma a obter os parâmetros, CMA, EL, Kf e n, relacionados aos fenômenos de adsorção. No estudo de correlação linear foram relacionados os parâmetros de adsorção obtidos e alguns atributos do solo, para verificar quais dentre esses atributos melhor se relacionam com o fenômeno de adsorção para os solos estudados. O grau de ajuste obtido pelas equações de Langmuir e Freundlich foi semelhante, para os elementos e para os solos, com valores de R2, em torno de 0,96. A isoterma do tipo L foi predominante para todos os metais e solos analisados, no entanto foram obtidas isotermas do tipo H para adsorção de Cd e Pb na amostra Terra Preta de Índio (A1). Todos os metais apresentaram correlação negativa entre a CMA e a fração areia do solo, para o grupo I. Cd, Cr, Cu e Pb também apresentaram correlação positiva entre EL, CMA e Kf com CTCef, P, Fed e Feo. A diversidade de características físicas, químicas e mineralógicas encontrada nos solos da bacia sedimentar Amazônica resultou na diferenciação quanto à capacidade máxima de adsorção de Cd, Cr, Cu e Pb. Os atributos do solo atuam favorecendo ou não a maior ou menor adsorção de metais, e isto controla a disponibilidade dos metais no meio. Assim, é imprescindível conhecer a dinâmica dos metais no solo, de forma a prever os riscos ambientais, com uso agrário ou industrial.
The soil, depending on their physical, chemical and mineralogical, can have a high ability to retain ions and molecules and can function as an excellent means to adsorb heavy metals. In the Amazon is the largest rainforest in the world, and the soil is the one responsible for sustaining vegetation in this region. The soil-vegetation interaction in this region provides different behavior of other Brazil soils. It is understood that adsorption studies of heavy metals in the Amazon soils contribute to the understanding of the behavior of these elements in those soils. Upon the assumption that more oxidic soils and more clayey minerals rich in 1:1 present a great capacity to adsorb heavy metals, while the adsorption of these metals will be lower in soils rich in 2: 1 minerals. This study aims to: conduct individual adsorption tests for heavy metals Cd, Cr, Cu e Pb for representative soils of sedimentary Amazon Basin with different mineralogical composition; evaluate the individual behavior of heavy metals front of soils; evaluate which of the isotherms of Langmuir and Freundlich best describes the adsorption of heavy metals in soils; determine the maximum adsorption capacity (MAC) of heavy metals in soil and; identify the relationship between the parameters of the isotherms and the attributes of the soil. The samples were selected according to their representation and distribution in the Amazon Basin Sediment collected in areas that did not exposed from the human action. The adsorption experiments were based on the principle that known amounts of soil and solution are brought into contact under agitation for a period of time until the system reaches equilibrium. The concentration of metals in solution after the balance was carried out by atomic absorption spectrophotometer. In the linear correlation study were related parameters obtained from the equation of Langmuir and Freundlich and some soil attributes to verify which of these attributes best describe the adsorption phenomenon for soils. The degree of fit obtained by Langmuir and Freundlich equation was similar, with R2 values of around 0.96. The isotherm L-type was predominant for all metals and analyzed soils, but were also observed isotherms type H for adsorption of Cd and Pb in the sample Terra Preta de Índio (A1). All metals showed negative correlation between the MAC and the sand fraction of the soil, for the group I. Cd, Cr, Cu and Pb also showed a positive correlation between EL, MAC and Kf with CECef, P, Fed and Feo. The diversity of physical, chemical and mineralogical characteristics of the soils found in the Amazon sedimentary basin showed the differentiation as to the maximum capacity adsorption of Cd, Cr, Cu and Pb in the study. Soil attributes act or not favoring a higher or lower metals adsorption, and this controls availability of the metal in the middle. Thus, it is essential to know the dynamics of metals in the soil, in order to predict environmental risks, with agricultural or industrial use.
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Střižíková, Romana. "Vzajemne hospodarske vztahy CR s Nemeckem." Master's thesis, Vysoká škola ekonomická v Praze, 2006. http://www.nusl.cz/ntk/nusl-161697.
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Vzajemne hospodarske vztahy Ceske republiky s Nemeckem jsou hodnoceny na zaklade analyzy objemove, teritorialni a zbozove struktury zahranicniho obchodu techto dvou zemi. Analyza je provedena take s ohledem na jednotlive spolkove zeme Nemecka a na jednotlive kraje Ceske republiky. Podstatna cast diplomove prace je venovana take analyze vzajemnych primych investic a vsem aspektum, ktere vyvoj PZI ovlivnuji.
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Sklenářová, Renáta. "Interakce hyaluronanu s DNA." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-295705.
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This diploma thesis deals with the study of possible interactions between hyaluronan (HA) and plasmid DNA (pDNA). Plasmid DNA was isolated from E. coli JM109 (pUC19) and resuspended in TE buffer as well as high molecular weight hyaluronan. Individual samples of pDNA, HA and pDNA-HA were characterized by gel electrophoresis, CD spectroscopy and high resolution ultrasonic spectroscopy. Agarose gel electrophoresis examined the effect of the addition of hyaluronan to plasmid DNA on the migration of samples to the positive electrode. Structural changes in pDNA-HA samples were examined using CD spectroscopy. Individual CD spectra describes the dependence of the difference in absorption coefficients for left-hand and right-handed elliptic polarized light at wavelength. High resolution ultrasonic spectroscopy has been used to study interactions. It is an analytical method based on ultrasonic velocity and attenuation. We classify this technique as a non-destructive method because the passing waves do not affect the structure of the analyzed sample.
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Augusto, Amanda dos Santos. "Determinação de Cd, Co, Cr, Cu, Ni e Pb em cosméticos infantis empregando técnicas espectroanalíticas." Universidade Federal de São Carlos, 2014. https://repositorio.ufscar.br/handle/ufscar/6597.
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Previous issue date: 2014-07-18Financiadora de Estudos e Projetos
In this study were developed two methods for sample preparation: one for children s eye shadow and another for chidren s lipstick. In the optimizing process, variables such as nitric acid concentration (2 or 7 mol L-1), sample mass (100 or 250 mg), heating time (1 or 3 hours) and concentration of Triton X-100 (5 or 25%) were investigated. The instrumental parameters of ICP OES were optimized in order to find a good working condition for the analytes determination. In the beginning it was performed a fractional factorial design 29- 5 (nine variables) and, after variables selection, a fine adjustment using Central Composite and Doehlert designs was made to study the most important variables (radio frequency power and nebulizer gas flow rate). In order to evaluate the regression models proposed, responses like LOQ and recovery for each analyte and in each view mode (radial and axial) were taken into consideration using desirability function. From the generated models it was possible to find the compromise condition with radio frequency power of 1200 W and a nebulizer gas flow rate of 0.825 L min-1. The methods developed for the preparation of the samples were applied to 22 samples of children cosmetics (14 eye shadows and 8 lipsticks). The analytes were determined using ICP OES (Cd, Co, Cr, Cu and Ni) and GF AAS (Pb). The majority of the concentrations obtained were lower than the international normatives, but the Pb values ranged from
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RAMBEAU, MAURO ODILE. "REHABILITATION PAR TRAITEMENT CHIMIQUE DE SOLS POLLUES PAR DES CATIONS (Cd, Cr, Cu, Ni, Zn)." Rennes 1, 1993. http://www.theses.fr/1993REN10022.
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Le but de cette these etait de trouver un procede de decontamination des sols pollues par des metaux lourds, realisable in situ, et sans effet sur la matrice du sol ou les nappes phreatiques. De nombreux essais ont montre qu'il n'est pas realisable de determiner une sequence de traitement universelle, et qu'il faut par consequent faire des essais prealables en laboratoire sur des echantillons, avant de s'attaquer aux sols. Une sequence de traitement a base de chlorure d'ammonium iii molaire et d'ammoniaque a toutefois ete retenue pour l'extraction du cadmium, cuivre, zinc, nickel et chrome contenus dans les sols. Cette extraction peut etre optimisee par l'ajout d'acide citrique a la sequence, ceci en prenant garde a la modification de ph engendree dans les sols. Ainsi fait, il ne restera, pour parfaire le traitement qu'a reenrichir les sols en oligo-elements, et eventuellement reajuster le ph
Books on the topic "Cd cr in s"
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Rodionov, Andreĭ. Pelʹmeni ustrit︠s︡y: Stikhi s prilozheniem na CD. Sankt Peterburg: Krasnyĭ matros, 2004.
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Crumpton, Trevor Edward. Characterisation of new phases synthesised by incorporating S,W,Mo, Cr, and Re oxoanions into Bi2O3. Birmingham: University of Birmingham, 2002.
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Marketing Research With Webcard And S P S S Cd-rom. Houghton Mifflin Company, 2003.
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ed, Schuller P., O'Neill I. K. ed, Fishbein L. 1923 ed, United Nations Environment Programme, and International Agency for Research on Cancer., eds. Some metals: As, Be, Cd, Cr, Ni, Pb, Se, Zn. Lyon: International Agency for Research on Cancer, 1986.
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Multimedia Kits: Roaring 20's & Depressing 30's *Cd. Teacher Created Resources, 2001.
Find full textBook chapters on the topic "Cd cr in s"
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Rael, Jane, and Steve Shelton. "Permeable Barriers to Remove Cd and Cr from Groundwater." In Environmental Technologies and Trends, 333–45. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/978-3-642-59235-5_23.
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Holze, Rudolf. "Ionic conductance of Cd(NO3)2+Cr(NO3)3." In Electrochemistry, 800. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-49251-2_753.
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Kono, Toru, and Alessandro Fichera. "Recurrent CD: Surgical Prophylaxis—Kono-S Anastomosis." In Crohn’s Disease, 227–36. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-14181-7_17.
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Franić, Mario, and Vlatko Galić. "As, Cd, Cr, Cu, Hg: Physiological Implications and Toxicity in Plants." In Plant Metallomics and Functional Omics, 209–51. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-19103-0_9.
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Cabrerizo, José Luis, Alfonso Carriazo, and Luis M. Fernández. "CR Submanifolds in (l.c.a.) Kaehler and S-manifolds." In Geometry of Cauchy-Riemann Submanifolds, 123–50. Singapore: Springer Singapore, 2016. http://dx.doi.org/10.1007/978-981-10-0916-7_5.
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Wachter, Joachim, Henri Brunner, Walter Meier, Umar Riaz, and M. David Curtis. "(μ-Disulfido-S)(η-Disulfido-η2:μ2)Bis-(η5-Pentamethylcyclopentadienyl)(μ-Thio)-Dichromium(Cr-Cr)." In Inorganic Syntheses, 69–70. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470132586.ch13.
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Khan, Muhammad Asif, and Varun Jeoti. "A Novel Design of Chaos Based S-Box Using Difference Distribution Table (CD S-Box)." In Communications in Computer and Information Science, 223–30. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-54525-2_20.
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Hall, D. W., and N. F. Borrelli. "Physical and Optical Properties of Cd(Se,S) Microcrystallites in Glass." In Photonic Switching, 122–24. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-73388-8_24.
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Schmid, D., G. J. Jäger-Waldau, and H. W. Schock. "Diffusion Length Measurement and Modeling of CuInSe2-(Zn,Cd)S Solar Cells." In Tenth E.C. Photovoltaic Solar Energy Conference, 935–38. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3622-8_239.
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Pardasani, R. T., and P. Pardasani. "Magnetic properties of S-bridged zinc bromide polynuclear complex composed of fac-(S)-[Cr(aet)3] units." In Magnetic Properties of Paramagnetic Compounds, 909–10. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-49202-4_445.
Full textConference papers on the topic "Cd cr in s"
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San Andrés, Luis, Jing Yang, and Rimpei Kawashita. "On the Effect of Clearance on the Leakage and Cavity Pressures in an Interlocking Labyrinth Seal Operating With and Without Swirl Brakes: Experiments and Predictions." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-14152.
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Abstract Gas labyrinth seals (LSs) improve turbomachinery operational efficiency and mechanical reliability by reducing secondary leakage. As interlocking labyrinth seals (ILSs) restrict more leakage than conventional see-through LSs, attention is due to their performance. An earlier paper [1] details the performance of a particular ILS in an ad-hoc test rig via measurements of mass flow (leakage) and cavity pressures while supplied with pressurized air at ambient temperature and operating with a rotor speed to a maximum of 10 krpm (surface speed 79 m/s). The test seal comprises of two teeth on the rotor and three teeth on the stator to make a four cavity seal with radial clearance Cr = 0.2 mm. The experimental and numerical leakages for the ILS produce a modified flow factor (Φ¯) that is independent of the seal operating conditions, namely inlet pressure, discharge pressure and rotor speed. The finding leads to an orifice-like loss coefficient cd = 0.36 and an effective clearance (cd × Cr) for the test seal, thus evidencing its effectiveness in reducing leakage. To complement the former research, this paper reports measurements of the leakage and cavity pressures for the same geometry interlocking labyrinth seals configured with two other clearances Cr = 0.3 mm and 0.13 mm. For the ILS with Cr = 0.3 mm, a first configuration is without a swirl brake (baseline), the second is with a swirl brake with 0° teeth pitch (axial ribs), and the third configuration is with a swirl brake with teeth angled at 40° in the direction of shaft rotation. For tests conducted without shaft rotation and with rotor spinning at 7.5 krpm (surface speed = 59 m/s), the inlet air pressure (Pin) ranges from 0.29 MPa to 0.98 MPa, while the exit pressure (Pout) is set to pressure ratios PR = (Pout/Pin) = 0.3, 0.5, 0.8. As to the ILS with Cr = 0.13 mm, it operates with an upstream swirl brake with axial ribs (0° teeth pitch) and w/o rotor speed. The supply pressure (Pin) varies from 0.59 MPa to 1.4 MPa and PR = 0.3, 0.5. The measurements and bulk-flow model predictions show that the seal mass leakage is proportional to the inlet pressure (Pin), increases as PR decreases, and is not affected by either shaft speed or the swirl brake configuration. Seal cavity static pressures drop linearly for all inlet pressures (Pin) and PR = 0.5 and above; except under a choked flow condition at PR = 0.3. Processing of the test data to consolidate the numerous leakage measurements delivers a nearly invariant flow factor Φ¯ for each seal clearance, and from this follows a unique orifice-like loss coefficient cd = 0.36 for the ILS with Cr = 0.3 mm, and cd = 0.33 for the ILS with Cr = 0.13 mm. This finding is remarkable as the test results obtained for the ILS with Cr = 0.2 mm also deliver a similar loss coefficient (cd = 0.36). Finally, predictions of ILS leakage and cavity pressures are within 5% of the measurements for all test conditions. The test data and predictions are of significant value to better the selection and design of gas labyrinth seals in turbomachinery.
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Sauliutė, Gintarė, Milda Stankevičiūtė, Gintaras Svecevičius, Janina Baršienė, and Roberta Valskienė. "Assessment of heavy metals bioconcentration factor (BCF) and genotoxicity response induced by metal mixture in Salmo salar tissues." In Environmental Engineering. VGTU Technika, 2017. http://dx.doi.org/10.3846/enviro.2017.043.
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The aim of this study was to evaluate metals bioconcentration factor (BCF) in gills, liver, kidneys and muscle in relation with genotoxicity effects of metal mixture in peripheral blood, kidneys, gills and liver erythrocytes of the Atlantic salmon (Salmo salar). Fish were exposed to maximum-permissible waterborne concentrations of Zn – 0.1, Cu – 0.01, Ni – 0.01, Cr – 0.01, Pb – 0.005 and Cd – 0.005 mg/L, respectively for 7 and 14 days. Genotoxicity was studied using the micronucleus test. In addition, erythrocyte nuclear abnormalities (ENAs) were analysed. Our study indicates that metal BCF in Atlantic salmon is tissue-dependent. Based on the BCF classification scale, the relatively low values of metals bioconcentration were assessed, except for Zn (gills) and Cu (liver) (359.6 and 594.0, respectively). Zn intensively concentrated in fish tissues, while Pb – least of all. Overall, metals were concentrated mostly in the liver, least – in the muscle. Significant differences among BCF values of Pb in gills and muscle and Cd in gills were measured between 7 and 14 d exposure groups. Treatment with metal mixture significantly increased micronucleus frequencies after 7 d of exposure in liver and peripheral blood erythrocytes. Significant genotoxicity response was not observed after 14 d treatment. The erythrocytic nuclei abnormalities determined in S. salar blood were nuclear bud on filament (NBf), nuclear bud (NB), blebbed (BL), kidney shaped, vacuolated (VacNuc), 8-shaped nuclei and fragmented-apoptotic (FA) erythrocytes. Significant elevation in total ENAs level was detected in kidneys and liver erythrocytes after 7 d treatment, while after 14 d – in gills and kidneys erythrocytes. No significant differences among analysed responses were measured between 7 and 14 d exposure groups, except total ENAs level in liver erythrocytes.
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Zhong, Zhaoping, Baosheng Jin, Yaji Huang, Hongcang Zhou, Davide Ross, and Masayuki Horio. "Study on Pollutants Emission Characteristic of Coal Gasification in a Fluidized Bed Test Rig." In 18th International Conference on Fluidized Bed Combustion. ASMEDC, 2005. http://dx.doi.org/10.1115/fbc2005-78070.
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This paper presents the results of coal gasification in a fluidized bed test rig of Xuzhou bituminous coal. The diameter of the fluidized bed combustor is 0.1m and the height is 4.22m. The bed temperature is maintained by a method of high temperature flue gas interline heating to overcome high heat losses associated with a oil burner. Test results are reported for variations in the bed temperature, air to coal, steam to coal and Ca to S ratio and their influence on gas yields and desulphurization efficiency. The distribution of polycyclic aromatic hydrocarbons (PAHs) and heavy metal trace elements into the char and syngas are also presented. The molar contents for CH4 and H2 in the coal syngas are found to decrease with increasing air to coal feed ratio from 2.5 to 5, while the content of CO shows little variation. Increasing the steam to coal feed ratio from 0.4 to 0.65 results in all three of the main gas components measured to form a local maximum content at a steam/coal feed ratio of 0.55. The efficiency of desulphurization improves as the ratio of Ca to S, air to coal and the bed temperature are increased, while decreasing with increasing steam to coal feed ratios. The volatile trace element species in decreasing order of relative mass ratio released into the gas phase are Hg, Se, As, Co, Cr, Cd, Cu, and Zn. Besides Hg, Se, and As, for all other trace heavy metals the majority of their mass distribution remains within the char with the proportion contained within char always greater than their combined yields in the coal syngas and slag. The total PAHs in the coal syngas is greater than that contained in the original coal and this indicates that PAHs are formed during the coal gasification process.
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Handa, Hitoshi, Satoshi Yamauchi, Kouji Hosono, and Hisatsugu Shirai. "Investigations of CD variation in Cr dry etching process." In Photomask Technology, edited by Brian J. Grenon and Giang T. Dao. SPIE, 2001. http://dx.doi.org/10.1117/12.410731.
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"CD label." In 2009 IEEE MTT-S International Microwave Symposium Digest. IEEE, 2009. http://dx.doi.org/10.1109/mwsym.2009.5165587.
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"CD booklet." In 2009 IEEE MTT-S International Microwave Symposium Digest. IEEE, 2009. http://dx.doi.org/10.1109/mwsym.2009.5165588.
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"CD welcome." In 2009 IEEE MTT-S International Microwave Symposium Digest. IEEE, 2009. http://dx.doi.org/10.1109/mwsym.2009.5165589.
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Constantine, Chris, Russell J. Westerman, and Jason Plumhoff. "Plasma etch of binary Cr masks: CD uniformity study of photomasks utilizing varying Cr loads." In Photomask Technology and Management, edited by Frank E. Abboud and Brian J. Grenon. SPIE, 1999. http://dx.doi.org/10.1117/12.373288.
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Constantine, Chris, Russell J. Westerman, and Jason Plumhoff. "Plasma etch of binary Cr masks: CD uniformity study of photomasks utilizing varying Cr loads: III." In Photomask Technology, edited by Brian J. Grenon and Giang T. Dao. SPIE, 2001. http://dx.doi.org/10.1117/12.410745.
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Min Huang and Bing He. "The World Expo’s history and principle evolve." In Conceptual Design (CAID/CD). IEEE, 2008. http://dx.doi.org/10.1109/caidcd.2008.4730800.
Full textReports on the topic "Cd cr in s"
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Thornton, E. C., and J. E. Amonette. Gas treatment of Cr(VI)-contaminated sediment samples from the North 60`s pits of the chemical waste landfill. Office of Scientific and Technical Information (OSTI), December 1997. http://dx.doi.org/10.2172/565355.
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Langowski, M. H. The incorporation of P, S, Cr, F, Cl, I, Mn, Ti, U, and Bi into simulated nuclear waste glasses: Literature study. Office of Scientific and Technical Information (OSTI), February 1996. http://dx.doi.org/10.2172/208366.
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Reynolds, Michael. Transition Metal Complexes of Cr, Mo, W and Mn Containing η1(S)-2,5-Dimethylthiophene, Benzothiophene and Dibenzothiophene Ligands. Office of Scientific and Technical Information (OSTI), September 2000. http://dx.doi.org/10.2172/764616.
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Kim, G. M., and G. H. Meier. Breakdown mechanisms of Al/sub 2/O/sub 3/, Cr/sub 2/O/sub 3/ and SiO/sub 2/ scales in H/sub 2//H/sub 2/O/H/sub 2/S environments: Final report, Volume 1. Office of Scientific and Technical Information (OSTI), January 1989. http://dx.doi.org/10.2172/5976591.
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Anderson, Andrew, and Mark Yacucci. Inventory and Statistical Characterization of Inorganic Soil Constituents in Illinois: Appendices. Illinois Center for Transportation, June 2021. http://dx.doi.org/10.36501/0197-9191/21-007.
Full textAbstract:
This report presents detailed histograms of data from the Regulated Substances Library (RSL) developed by the Illinois Department of Transportation (IDOT). RSL data are provided for state and IDOT region, IDOT district, and county spatial subsets to examine the spatial variability and its relationship to thresholds defining natural background concentrations. The RSL is comprised of surficial soil chemistry data obtained from rights-of-way (ROW) subsurface soil sampling conducted for routine preliminary site investigations. A selection of 22 inorganic soil analytes are examined in this report: Al, Sb, As, Ba, Be, Cd, Ca, Cr, Co, Cu, Fe, Pb, Mg, Mn, Hg, Ni, K, Se, Na, Tl, V, and Zn. RSL database summary statistics, mean, median, minimum, maximum, 5th percentile, and 95th percentile, are determined for Illinois counties and for recognized environmental concern, non-recognized environmental concern, and de minimis site contamination classifications.
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Anderson, Andrew, and Mark Yacucci. Inventory and Statistical Characterization of Inorganic Soil Constituents in Illinois. Illinois Center for Transportation, June 2021. http://dx.doi.org/10.36501/0197-9191/21-006.
Full textAbstract:
This report presents a statistical analysis of the Regulated Substances Library (RSL) developed by the Illinois Department of Transportation. The RSL is comprised of surficial soil chemistry data obtained from rights-of-way subsurface soil sampling conducted for routine preliminary site investigations. The 3.7-million-record RSL database is compared with four independent studies of inorganic soil constituents of naturally occurring soils in Illinois. A selection of 22 inorganic soil analytes are examined in this study: Al, Sb, As, Ba, Be, Cd, Ca, Cr, Co, Cu, Fe, Pb, Mg, Mn, Hg, Ni, K, Se, Na, Tl, V, and Zn. RSL database summary statistics, mean, median, minimum, maximum, 5th percentile, and 95th percentile, are determined for Illinois counties and for recognized environmental concern, non-recognized environmental concern, and de minimis site contamination classifications. The RSL database at a 95% confidence level is compared with current and proposed thresholds for defining naturally occurring soil concentrations for the selected analytes. The revised thresholds proposed by Cahill in 2017 are predominantly larger than the current standards found in the Tiered Approach to Corrective Action Objectives rules and are in better agreement with observed distributions of soil concentrations for both naturally occurring and RSL soils. A notable exception is antimony (Sb), for which Cahill proposed a reduced threshold similar in magnitude to the median for many Illinois Department of Transportation districts.