Relevant bibliographies by topics / Cd absorption

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Academic literature on the topic 'Cd absorption'

Author: Grafiati
Published: 4 June 2021
Last updated: 20 February 2023

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Journal articles on the topic "Cd absorption"

1

Chen, Su, Lei Chao, Li Na Sun, and Tie Heng Sun. "Competition Absorption and Desorption Dynamic Character of Cadmium, Lead and Zinc by Soil in North-East of China." Advanced Materials Research 356-360 (October 2011): 52–58. http://dx.doi.org/10.4028/www.scientific.net/amr.356-360.52.

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The competitive absorption and desorption of cadmium (Cd), lead (Pb) and zinc (Zn) in meadow brown soil from Liaoning province in north-east China was studied in the paper in order to establish the selectivity sequences for the sorption and desorption of these heavy metals in the soil and obtain the absorption and desorption dynamic character of these heavy metals. The results showed that with the increasing of the absorption times, the absorption quantities of Cd, Pb and Zn were increased little by little. The absorption process of Cd, Pb and Zn could be divided into the fast absorption phase and the slow absorption phase. And the fast absorption phases were from the beginning to 60 min, 120 min and 120 min for Cd, Pb and Zn, respectively. The more company metals (i.e. Pb and Zn) existed in the absorption solutions, the less absorption quantities of Cd absorbed by soil. The co-existence of Cd, Pb and Zn had obviously decreased the absorption of Pb by soil. And it was the same situation that Zn absorbed by soil was decreased by the company metals such as Cd, Pb. The company metals had obvious influence on the desorption process of Cd. The existence of Pb and Zn promoted the desorption of Cd. And desorption behavior of Zn was bated by the existence of Pb and Cd. While the company metals Cd and Zn restrained the desorption of Pb. The best equation to describe the absorption and desorption dynamic character of Cd, Pb and Zn was Elovich equation, next was Two–constant equation, and the effect of First-order dynamics equation was not good.
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Callegaro, MGK, BG Milbradt, E. Alves, T. Diettrich, DM Kemerich, BS Hausen, FA Duarte, EMM Flores, VL Dressler, and T. Emanuelli. "Effect of wheat bran and flaxseed on cadmium effects and retention in rats." Human & Experimental Toxicology 30, no. 8 (September 27, 2010): 981–91. http://dx.doi.org/10.1177/0960327110384526.

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Dietary fiber can affect cadmium (Cd) absorption and toxicity, but the effect appears to depend on the type of dietary fiber. The aim of the present study was to compare the effect of dietary sources containing distinct amounts of soluble and insoluble fiber on Cd absorption, accumulation and toxicity in growing rats. The absorption of essential macrominerals (Ca, P and Mg) was also evaluated. Animals received a nutritionally balanced diet with cellulose (cel — control), wheat bran or flaxseed as the fiber source with 0 or 50 mg Cd kg-1 diet, during 30 days. Cd exposure reduced body weight gain, feed efficiency ratio, epididymal fat relative weight and liver relative weight, and increased plasma alanine aminotransferase activity in all fiber groups. The apparent Cd absorption was similar among Cd-groups, but the flax-Cd group had a higher hepatic and renal Cd concentration. Cd decreased the absorption of Ca and P, and increased Mg absorption in the wheat bran and flaxseed groups, but not in the cel group. Although the different fiber sources investigated had no effect on Cd toxicity, the major soluble fiber source, flaxseed, increased Cd retention. Thus, caution should be taken in the intake of flaxseed by Cd-exposed populations.
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Erika Mulyana Gultom and M. Turmuzi Lubis. "APLIKASI KARBON AKTIF DARI CANGKANG KELAPA SAWIT DENGAN AKTIVATOR H3PO4 UNTUK PENYERAPAN LOGAM BERAT Cd DAN Pb." Jurnal Teknik Kimia USU 3, no. 1 (March 31, 2014): 5–10. http://dx.doi.org/10.32734/jtk.v3i1.1493.

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This research aims to determine the optimum conditions ofactivated carbon made of palm shells activated with H3PO4as an absorber of heavy metals such as Cd and Pb. The research methodology includes the preparation of activated carbon, absorption, and testing. Absorption stage is done by varying the concentration of heavy metals are 5 ppm, 10 ppm, 15 ppm, 20 ppm and activated carbon mass per run, which is0.5 grams. Another variable are the contact time with intervals of 5 minutes and the pH arranged heavy metals 2-9. Testing activated carbon absorption to heavy metals using atomic adsorption spectrofotometric (AAS). The results showed that the most optimum absorption is concentration of 10 ppm, 40 minutes and pH absorption3-4. Absorption of heavy metals Cd and Pb obtained 84,61 % and 80,13 %.
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Thomas, Carla, and Phillip S. Oates. "Copper deficiency increases iron absorption in the rat." American Journal of Physiology-Gastrointestinal and Liver Physiology 285, no. 5 (November 2003): G789—G795. http://dx.doi.org/10.1152/ajpgi.00509.2002.

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Release of iron from enterocytes and hepatocytes is thought to require the copper-dependent ferroxidase activity of hephaestin (Hp) and ceruloplasmin (Cp), respectively. In swine, copper deficiency (CD) impairs iron absorption, but whether this occurs in rats is unclear. By feeding a diet deficient in copper, CD was produced, as evidenced by the loss of copper-dependent plasma ferroxidase I activity, and in enterocytes, CD reduced copper levels and copper-dependent oxidase activity. Hematocrit was reduced, and liver iron was doubled. CD reduced duodenal mucosal iron and ferritin, whereas CD increased iron absorption. Duodenal mucosal DMT1-IRE and ferroportin1 expression remained constant with CD. When absorption in CD rats was compared with that seen normally and in iron-deficient anemic animals, strong correlations were found among mucosal iron, ferritin, and iron absorption, suggesting that the level of iron absorption was appropriate given that the erythroid and stores stimulators of iron absorption are opposed in CD. Because CD reduced the activity of Cp, as evidenced by copper-dependent plasma ferroxidase I activity and hepatocyte iron accumulation, but iron absorption increased, it is unlikely that the ferroxidase activity of Hp is important and suggests another function for this protein in the export of iron from the enterocyte during iron absorption. Also, the copper-dependent ferroxidase activity of Cp does not appear important for iron efflux from macrophages, because Kupffer cells of the liver and nonheme iron levels of the spleen were normal during copper deficiency, suggesting another role for Cp in these cells.
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Schreinemakers, W. A. C. "THE INTERACTION BETWEEN Cd-ABSORPTION AND Cd-COMPARTMENTATION IN WOLFFIELLA GLADIATA." Acta Botanica Neerlandica 35, no. 1 (February 1986): 23–34. http://dx.doi.org/10.1111/j.1438-8677.1986.tb00443.x.

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Jobe, David J., Ronald E. Verrall, and Vincent C. Reinsborough. "Ultrasonic absorption studies in aqueous solutions of modified β-cyclodextrins." Canadian Journal of Chemistry 68, no. 12 (December 1, 1990): 2131–36. http://dx.doi.org/10.1139/v90-327.

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Ultrasonic absorption studies over the frequency range 0.6–210 MHz were conducted in aqueous solutions of the following modified β-cyclodextrins (β-CD): 2,6-O-dimethyl-β-CD (DMβCD), 2,3,6-O-trimethyl-β-CD(TMβCD), and hydroxypropyl-β-CD (HPβCD). Anomalous ultrasonic absorption found in the three systems was attributed to three relaxations in the DMβCD and HPβCD systems and two in the TMβCD system. These relaxations were assigned to hydrogen bond "wig-wagging", to CD cavity water exchange, and to bond rotation within the CD units. The 1:1 DMβCD/decyltrimethylammonium bromide system was also investigated ultrasonically in solution. Keywords: ultrasonic absorption, modified β-cyclodextrins, surfactant inclusion, relaxation frequency.
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Zhao, Shouping, Qi Zhang, Wendan Xiao, De Chen, and Xuezhu Ye. "Absorption of cadmium accompanied by EDTA varies according to tomato cultivar." Crop and Pasture Science 70, no. 11 (2019): 981. http://dx.doi.org/10.1071/cp19130.

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Two tomato (Lycopersicum solanum) varieties, one high (YSL189) and one low (HZ903) cadmium (Cd) accumulator, were used in our experiment. We detected cadmium (Cd ion/Cd-EDTA) uptake rates in roots and the corresponding expression of the Cd transport genes IRT1, IRT2, ZIP, Nramp1, Nramp2 and Nramp3. Our data proved that both cultivars – YSL189 and HZ903 – showed higher Cd accumulation in plants and a higher Cd uptake rate in roots supplied with Cd ion than with Cd-EDTA. In roots of YSL189, the expression levels of IRT1, IRT2, ZIP, Nramp1, Nramp3 and Nramp2 (5, 10 and 20 µmolc L–1 Cd) treated with Cd ion were higher than those treated with Cd-EDTA, whereas in roots of HZ903, only two genes, IRT1 and Nramp1 (5, 10, 100 µmolc L–1 Cd), showed higher expression levels in plants treated with Cd ion than in those treated with Cd-EDTA. When the difference between the cultivars was considered, the Cd concentration in the plant and the Cd uptake rate in the roots of YSL189 were higher than those of YZ903 under the same Cd treatments (i.e. Cd ion or Cd-EDTA). The expression of IRT2 and ZIP in the roots of YSL189 was higher than that observed in HZ903 treated with all levels of ion-Cd. We attribute the higher Cd uptake rate and greater accumulation of ion-Cd compared with EDTA-Cd in YSL189 than those found in HZ903 partly to the genes that had higher expression levels. Our results indicate that the roles of transporters in the absorption of different forms of Cd vary according to plant genotype.
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de la Peña, Arsenio Muñoz, Rezik A. Agbaria, Montserrat Sánchez Peña, and Isiah M. Warner. "Spectroscopic Studies of the Interaction of 1,4-Diphenyl-1,3-Butadiene with α-, β-, and γ-Cyclodextrins." Applied Spectroscopy 51, no. 2 (February 1997): 153–59. http://dx.doi.org/10.1366/0003702971939983.

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Steady-state fluorescence, anisotropy, and UV-visible absorption measurements have been used to investigate the structure and spectroscopic characteristics of the complexes formed by trans, trans-1,4-diphenyl-1,3-butadiene (DPB) with α-, β-, and γ-cyclodextrins (CDs). The behavior of α-CD with DPB is very different from that of DPB with respect to β-CD or γ-CD. In the presence of α-CD, clear solutions with high absorption and fluorescence emission, relatively high anisotropy, a rapid equilibrium reaction, and Benesi–Hildebrand plots lead us to conclude that normal 2:1 inclusion compounds are formed. In the presence of γ-CD, turbid solutions, with absorption and fluorescence emission intensities lower than those in α-CD, higher values of anisotropy, slow equilibrium reaction, and spectral shifts to the red in the absorption, excitation, and emission wavelengths are evidence of the formation of extended linear aggregates. In the presence of β-CD, both mechanisms of inclusion appear to be present.
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Zhai, Qixiao, Fengwei Tian, Jianxin Zhao, Hao Zhang, Arjan Narbad, and Wei Chen. "Oral Administration of Probiotics Inhibits Absorption of the Heavy Metal Cadmium by Protecting the Intestinal Barrier." Applied and Environmental Microbiology 82, no. 14 (May 20, 2016): 4429–40. http://dx.doi.org/10.1128/aem.00695-16.

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ABSTRACTThe heavy metal cadmium (Cd) is an environmental pollutant that causes adverse health effects in humans and animals. Our previous work demonstrated that oral administration of probiotics can significantly inhibit Cd absorption in the intestines of mice, but further evidence is needed to gain insights into the related protection mode. The goal of this study was to evaluate whether probiotics can inhibit Cd absorption through routes other than the Cd binding, with a focus on gut barrier protection. In thein vitroassay, both the intervention and therapy treatments ofLactobacillus plantarumCCFM8610 alleviated Cd-induced cytotoxicity in the human intestinal cell line HT-29 and protected the disruption of tight junctions in the cell monolayers. In a mouse model, probiotics with either good Cd-binding or antioxidative ability increased fecal Cd levels and decreased Cd accumulation in the tissue of Cd-exposed mice. Compared with the Cd-only group, cotreatment with probiotics also reversed the disruption of tight junctions, alleviated inflammation, and decreased the intestinal permeability of mice.L. plantarumCCFM8610, a strain with both good Cd binding and antioxidative abilities, exhibited significantly better protection than the other two strains. These results suggest that along with initial intestinal Cd sequestration, probiotics can inhibit Cd absorption by protecting the intestinal barrier, and the protection is related to the alleviation of Cd-induced oxidative stress. A probiotic with both good Cd-binding and antioxidative capacities can be used as a daily supplement for the prevention of oral Cd exposure.IMPORTANCEThe heavy metal cadmium (Cd) is an environmental pollutant that causes adverse health effects in humans and animals. For the general population, food and drinking water are the main sources of Cd exposure due to the biomagnification of Cd within the food chain; therefore, the intestinal tract is the first organ that is susceptible to Cd contamination. Moreover, Cd exposure causes the disruption of the intestinal barrier and further induces the amplification of Cd absorption. The present study confirms that, along with initial intestinal Cd sequestration, oral administration of probiotics can inhibit Cd absorption by protecting the intestinal barrier. A probiotic with both good Cd-binding and antioxidative capacities can be used as a daily supplement for the prevention of oral Cd exposure.
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Moberg Wing, Anncatherine. "The effects of whole wheat, wheat bran and zinc in the diet on the absorption and accumulation of cadmium in rats." British Journal of Nutrition 69, no. 1 (January 1993): 199–209. http://dx.doi.org/10.1079/bjn19930022.

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The purpose of the present study was to determine if the inclusion of whole-grain wheat or wheat bran in the diet or the addition of Zn to the diet affects the absorption and accumulation of Cd. Five groups of six rats each were fed deionized water and one of five diets composed of one part basic diet and one part wheat crispbread for 6 weeks. The accumulation of Cd in the liver and kidneys was measured using atomic absorption spectrometry and estimated by measuring the absorption and retention of 109Cd from a single meal after 3 weeks on the diets. The fractional accumulation of Cd in the liver and kidneys was lower in rats fed on whole-wheat and bran diets than in those fed on wheat-endosperm diets. As adding Zn or Cd to endosperm diets to approximate the bran and whole-wheat diet levels had no effect on the fractional Cd absorption, the reduced absorption from the whole-wheat and bran diets is probably not due to their higher Zn and Cd concentrations but may be due to their higher fibre or phytate concentrations. The amount of Cd concentrations.
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Dissertations / Theses on the topic "Cd absorption"

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Johnson, William H. "Sorption models for U, Cs, and Cd on upper Atlantic Coastal Plain soils." Thesis, Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/16609.

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Ngobeni, P., C. Canario, DA Katskov, and Y. Thomassen. "Transverse heated filter atomizer: atomic absorption determination of Pb and Cd in urine." Journal of Analytical Atomic Spectroscopy, 2003. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000894.

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A transverse heated filter atomizer (THFA) was applied to the direct determination of Cd and Pb in urine, and its analytical performances were investigated using a PerkinElmer SIMAA 6000 atomic absorption spectrometer. Seronorm certified human urine reference materials and six realistic samples collected locally were used for the method validation. The urines were diluted ten- or five-fold with 0.2% HNO3. Cd and Pb nitrate solutions were employed as standards. Recoveries of the elements from the urine samples were investigated with the analyte addition method. Compared to the transverse heated graphite atomizer (THGA) with a platform, the THFA provided a significant reduction of spectral background and chemical interferences from the urine matrix, without the use of chemical matrix modifiers, a 1.5–2 times increase of the determination sensitivity and, therefore, a reduction of limits of detection up to 0.018 and 0.2 mg L21 for Cd and Pb, respectively. The use of a THFA collector made from carbon fiber and a tungsten wire improved recoveries of lead and cadmium in urine (¢92%). A sampling temperature 150 uC enabled us to skip the drying period, thus a significantly reduced temperature program was obtained. The accuracies of the measurements of Cd and Pb in the Seronorm urine materials were in good agreement with the recommended values: 4.1 ¡ 0.1 mg L21 of Cd (recommended 5) and 92 ¡ 1 mg L21 of Pb (recommended 85). The lifetime of the THFA for Pb determination was longer than 700 firings, with the sensitivity loss not more than 25% after 500 firings.
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Jinadasa, N., of Western Sydney Hawkesbury University, of Science Technology and Agriculture Faculty, and School of Horticulture. "Cadmium effects on vegetables : production, physiology and biochemistry." THESIS_FSTA_HOR_Jinadasa_K.xml, 1998. http://handle.uws.edu.au:8081/1959.7/456.

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Cadmium (Cd) is absorbed through the lungs and the digestive tract; however, for most human non-smokers, the major route of Cd entry into the body is by ingestion. Perhaps 5% of ingested Cd is absorbed and once absorbed, Cd accumulates mostly in the liver and kidneys, where it can cause a variety of health problems. This applies equally to grazing stock. The major entry point of Cd into the food chain is therefore uptakes of traces of Cd by crop plants. This thesis focuses on Cd in vegetables. The study was conducted in an Australian context, where geogenic Cd contributions to soils are typically low. Most of the Cd in soils on Australian vegetable farms originates from materials added to boost crop production. Phosphate fertilisers were and remain the dominant Cd source. Most Australian soils are P-deficient and high rates of P fertiliser are essential for successful vegetable cropping. The P fertilisers used throughout Australia were formerly made from guano deposits mined on Pacific Islands. These contained high percentages of Cd. Current rock sources contain lower Cd concentrations. Studies showed that all the vegetable samples which contained excessive Cd concentrations were leafy vegetables, including cabbage, lettuce, silverbeet, parsley and bok choy. Cadmium impaired photosynthesis; reduced dry weight of the whole plant; slowed leaf elongation rate; decreased the length of fully expanded leaves; slowed the rate at which new leaves appeared; and altered foliar concentrations of Zn, Mn, Cu, Ca and S. These profound changes affected all parts of the plant; consequently, Cd did not affect the proportion of dry weight partitioned to the roots, stems and leaves.
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Heinrich, Hannah Tabea Monika, and n/a. "Acid-base and Cd�⁺ adsorption properties of two thermophilic bacteria." University of Otago. Department of Chemistry, 2007. http://adt.otago.ac.nz./public/adt-NZDU20080107.095128.

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The release of toxic metal species is of concern due to their detrimental effects on the environment and human health. Industrial effluents are a major source of mobilised metal species. Suitable technologies are needed to sequester toxic metal species at the point of source. Biosorption, which is based on the passive adsorption of contaminants onto biological materials, promises to offer an effective alternative or complementary step to existing treatment methods. However, to date there has been no widespread commercialisation of the technique. This is partly due to an insufficient understanding of the complex underlying mechanisms which makes it difficult to select suitable biomass for specific remediation problems and to predict process performance. This study characterised two gram-positive, thermophilic bacteria, Anoxybacillus flavithermus (BF) and Geobacillus stearothermophilus (BS), harvested at two different growth times, with regard to their acid-base and Cd�⁺ adsorption behaviour. The aim was to investigate the metal cation adsorption properties of thermophilic bacteria which has not been studied previously, and to gain a better understanding of the interactions responsible for bacterial metal cation adsorption. Experimental techniques employed in this study included microscopy to establish cell and cell wall morphology, batch acid-base and Cd�⁺ adsorption experiments to quantify proton active surface functional groups and Cd�⁺ adsorption, electrophoretic mobility measurements to assess the overall surface charge of the bacteria and in situ attenuated total reflection infrared (ATR-IR) spectroscopy to reveal the chemical identities of functional groups. Chemical equilibrium models based on batch acid-base titration and electrophoretic mobility data were developed to quantitatively describe proton active surface functional groups. These groups can also interact with metal cations. It was found that growth time was an important factor in all experiments with the differences between growth times often being more pronounced than the differences between the two bacterial strains. Microscopy revealed a gram-positive cell wall structure with different widths and staining behaviour for exponential phase cells of BF and BS. Stationary / death phase cells showed disintegrating cell walls. Acid-base titrations indicated that all cells possessed buffering capacity over the whole investigated pH range (pH 2 - 10). From electrophoretic mobility measurements, isoelectric points of ~ 3.2 for BF and < 1.8 and ~ 4.2 for exponential and stationary / death phase cells of BS respectively were estimated. Chemical equilibrium models including a Donnan electrostatic model were derived which described both the batch acid-base titration data and the electrophoretic mobility data reasonably well, although a comparison with IR data suggested room for further improvement. In situ ATR-IR spectroscopy of hydrated bacterial cells at various pH values revealed amide and carboxyl groups and a contribution from phosphate / polysaccharide moieties. Group specific interactions with Cd�⁺ were not detected, however, a partially reversible absorbance increase of all peaks suggested conformational changes in the presence of Cd�⁺. BF and BS adsorbed ~ 70 [mu]mol Cd�⁺ (g dry bacterial)⁻� at pH 5 in 0.01 M NaNO₃. Release of major cations occurred concomitantly with Cd�⁺ adsorption. The buffering and Cd�⁺-binding capacities of BF and BS were found to be comparable to those of mesophilic bacteria and ion exchange was identified as an important adsorption mechanism.
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Deng, Hong. "Metal (Pb, Zn, Cu, Cd, Fe) uptake, tolerance and radial oxygen loss in typical wetland plants." HKBU Institutional Repository, 2005. http://repository.hkbu.edu.hk/etd_ra/629.

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Etchebers, Olivier. "Etude pluricontextuelle et pluridimensionnelle de la mobilité des métaux lourds (Cd, Ni, Pb) dans les sols." Pau, 2004. http://www.theses.fr/2004PAUU3004.

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La mobilité des métaux lourds est étudiée dans trois contextes de contamination, chacun à une échelle différente. Le premier est l'épandage de boues de station d'épuration sur sol forestier. Les processus sont accélérés par centrifugation, en microcosme. Malgré plusieurs mois d'évolution simulée, la migration des métaux (Cd, Ni, Pb) reste très limitée, vraisemblablement par affinité avec la matière organique accumulée en surface. Le deuxième est réalisé en mésocosme, à partir d'une terre agricole dopée en Pb. Après plusieurs mois en milieu extérieur, le Pb est retenu dans le solide. Il est adsorbé sur les particules organiques et argileuses (montmorillonite) mais reste potentiellement mobilisable. Le troisième concerne un aquifère sous un site industriel (macrocosme) pollué en Cu et H2SO4. L'acidité favorise la solubilité du Cd et du Pb. Cependant, le pouvoir tampon du solide entraîne la précipitation du Cu et du Fe; et l'immobilisation du Cd et du Pb par adsorption ou coprécipitation
The mobility of heavy metals is studied on three cases of contamination, each one at a different scale. The first one deals with spreading of sewage sludge on forest soils. Processes are accelerated under centrifugation, at microcosm scale. Despite several months of simulated evolution, migration of heavy metals (Cd, Ni, Pb) is quite limited, probably by affinity with organic matter accumulated at the surface. The second one is run at mesocosm scale, using an agricultural soil spiked with Pb. After several months outdoor, Pb is retained within the solid. It is adsorbed on organic and clay (montmorillonite) particles, but remains under a potentially soluble form. The third one corresponds to an aquifer underlying an industrial site (macrocosm) polluted by Cu and H2SO4. Acidity enhances the solubility of Cd and Pb. However, the buffer capacity of the solid induces the precipitation of Cu and Fe; and the fixation of Cd and Pb by adsorption or coprecipitation
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Zahedy, Fakhri S., Hsiao-Wen Chen, Michael Rauch, and Ann Zabludoff. "HST Detection of Extended Neutral Hydrogen in a Massive Elliptical at z = 0.4." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/625809.

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We report the first detection of extended neutral hydrogen (H I) gas in the interstellar medium (ISM) of a massive elliptical galaxy beyond z similar to 0. The observations utilize the doubly lensed images of QSO HE 0047-1756 at z(QSO) = 1.676 as absorption-line probes of the ISM in the massive (M-star approximate to 10(11) M-circle dot) elliptical lens at z = 0.408, detecting gas at projected distances of d = 3.3 and 4.6 kpc on opposite sides of the lens. Using the Space Telescope Imaging Spectrograph, we obtain UV absorption spectra of the lensed QSO and identify a prominent flux discontinuity and associated absorption features matching the Lyman series transitions at z = 0.408 in both sightlines. The H I column density is log N(H I)= 19.6-19.7 at both locations across the lens, comparable to what is seen in 21 cm images of nearby ellipticals. The H I gas kinematics are well-matched with the kinematics of the Fe II absorption complex revealed in ground-based echelle data, displaying a large velocity shear of approximate to 360 km s(-1) across the galaxy. We estimate an ISM Fe abundance of 0.3-0.4 solar at both locations. Including likely dust depletions increases the estimated Fe abundances to solar or supersolar, similar to those of the hot ISM and stars of nearby ellipticals. Assuming 100% covering fraction of this Fe-enriched gas, we infer a total Fe mass of M-cool(Fe) similar to (5-8) x 10(4) M-circle dot in the cool ISM of the massive elliptical lens, which is no more than 5% of the total Fe mass observed in the hot ISM.
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Carvalho, José Wilson Pires. "Estudo da estabilidade térmica da hemoglobina extracelular gigante de Glossoscolex paulistus (HbGp): efeitos do estado de oxidação do ferro do grupo heme, pH e presença de surfactante." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/75/75134/tde-28112013-112257/.

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A hemoglobina extracelular de Glossoscolex paulistus (HbGp) possui estrutura oligomérica composta por 144 cadeias globínicas e 36 cadeias linkers, que não possuem heme, formando uma bicamada hexagonal. Estudos mostraram que a HbGp possui uma alta estabilidade á variação de pH e presença de agentes desnaturantes, tais como, surfactantes e ureia, a 25°C. Com esses conhecimentos prévios, o presente estudo tem por objetivo avaliar a estabilidade térmica da HbGp 0,5-3,0 mg/mL, nas formas oxi-, meta- e cianometa-, em diferentes valores de pH. O efeito do SDS na estabilidade térmica da oxi-HbGp 0,5 e 3,0 mg/mL, em função do pH, será investigado também. Esses estudos foram realizados usando as técnicas de absorção óptica, dicroísmo circular (CD), espalhamento de luz dinâmico (DLS) e espalhamento de raios X a baixo ângulo (SAXS). Os resultados de absorção óptica e CD revelam que o processo de desnaturação da oxi- e cianometa-HbGp, no pH 7,0, envolve a formação das espécies oxidadas aquo-meta-HbGp e hemicromo. O processo de desnaturação é próximo ao modelo de dois estados, com uma temperatura crítica (Tc) de 58-59 °C. No pH ácido, a proteína agrega a partir de 58 °C. A cinética de agregação da oxi-HbGp, no pH 7,0, é dependente da concentração de proteína e da temperatura. Os dados de DLS mostram que a meta- e cianometa-HbGp 0,5 mg/mL, pH 7,0, desnaturam a 48 ± 1 e 56 ± 1 °C, respectivamente. Em pH alcalino, a proteína dissocia parcialmente antes de desnaturar, e o aumento da concentração de proteína faz aumentar o valor de Tc para a cianometa-HbGp. Dados de SAXS mostram que a oxi- e meta-HbGp, pH 7,0, desnaturam a 60 °C, apresentando valores de Rg=143±1 Å e Dmax=450±1 Å, enquanto que a cianometa-HbGp se mantém estável, com valores de Rg=107±1 Å e Dmax=300±1 Å. As análises das curvas p(r) mostram uma porcentagem crescente de dodecâmero e tetrâmero em solução, em relação à fração de protreína íntegra e de subunidades maiores, com o aumento do pH e da temperatura. As análises baseadas no programa OLIGOMER são similares às baseadas na função p(r). A presença do SDS induz a dissociação da oxi-HbGp 0,5 mg/mL pH 7,0. Entretanto, com 3,0 mg/mL de proteína a dissociação é parcial, com a sobreposição dos processos de dissociação, desnaturação e agregação, com o aumento da temperatura. No pH 5,0, o SDS promove a agregação da oxi-HbGp em temperaturas menores. As constantes cinéticas de dissociação da oxi-HbGp 0,5 mg/mL, pH 7,0 aumentam de (0,53±0,07)x10-4 s-1 para (2,1±0,2)x10-4 s-1 na presença de 0,4 e 0,6 mmol/L de SDS a 40 °C, respectivamente. Na temperatura de 42 °C a constante aumenta 2,6 vezes, com 0,6 mmol/L de SDS, comparada a 40 °C. A oxi-HbGp 3,0 mg/ml na presença de 0,6 mmol/L de SDS, dissocia parcialmente em tempos menores com o aumento da temperatura antes de agregar. Portanto, esses estudos mostram que a estabilidade térmica da HbGp é sensível ao aumento de pH e presença de SDS. A ordem de estabilidade térmica em pH alcalino é dado por: cianometa->oxi->meta-HbGp. Alem disso, o processo de desnaturação é governado pelo valor do pH e dependente da concentração de proteína em solução.
The extracellular hemoglobin Glossoscolex paulistus of (HbGp) has an oligomeric structure composed by 144 globin chains and 36 non globin chains (named linkers), forming a hexagonal bilayer. HbGp presents a high stability reagarding pH variation and the presence of denaturing agents, such as, for example, urea and surfactant, at 25°C. In this way, the present studies aim to evaluate the thermal stability for oxy-, meta- and cyanomet-HbGp 0.5-3.0 mg/ml, at different pH values. The SDS effect on the thermal stability of oxy-HbGp 0.5 and 3.0 mg / mL is also investigated. Optical absorption, circular dichroism (CD), dynamic light scattering (DLS) and small angle X-ray scattering (SAXS) techniques were emplayed for these studies. The results based on the optical absorption and CD spectroscopies show that the denaturation process for oxy- and cyanomet-HbGp, at pH 7.0, involves the formation of oxidized species, such as aquo-met-HbGp and hemichrome. This denaturation process is very close to a two-state model, with a critical temperature (Tc) of 58-59 °C. However, in the acidic pH, the aggregation of protein occurs at 58 °C. The aggregation process kinetics for oxy-HbGp, pH 7.0, is dependent on the protein concentration and temperature. DLS data show that meta- and cyanomet-HbGp, 0.5 mg/mL, pH 7.0, undergo denaturation at 48 ± 1 and 56 ± 1 ° C, respectively. At alkaline pH, two HbGp forms undergo partial dissociation before denaturation, and at higher protein concentration, an increase of Tc values for cyanomet-HbGp is observed. SAXS results show that the denaturation of oxy-and met-HbGp occur at 60 °C, presenting Rg=143±1 Å and Dmax=450±15 Å, while cyanomet-HbGp remains stable with Rg =107±1 Å and Dmax= 300±10Å, at this temperature. The p(r) curves analysis show the increase of dodecamer and tetramer percentages in solution, with increase of pH and temperature. The results using the OLIGOMER program are similar to the p(r) data analysis. For oxy-HbGp 0.5 mg/mL pH 7.0, in the presence of SDS, oligomeric dissociation before denaturation is observed. However, with 3.0 mg/ml of protein the dissociation process is slower, showing an overlap of the dissociation, denaturation and aggregation processes in the system, with increase of temperature. At pH 5.0, SDS promotes the aggregation of oxy-HbGp at lower temperatures, as compared to the absence of surfactant. The kinetic dissociation constant values for oxy-HbGp 0.5 mg/mL increase from (0.53 ± 0.07) x10-4 s-1 to (2.1 ± 0.2) x10-4 s-1, in the presence of 0.4 and 0.6 mmol/L SDS at 40 ° C, respectively. At 42 °C the dissociation constant value increases 2.6-fold, with 0.6 mmol/L SDS, as compared to 40 °C. For oxy-HbGp 3.0 mg/ml, in the presence of 0.6 mmol/L SDS, the oligomeric dissociation is smallest occurring in shorter times with increasing temperature before aggregation. Therefore, these studies show that the thermal stability of HbGp is sensitive to the pH variation and the presence of SDS. At alkaline pH, the order of thermal stability is the following: cyanomet->oxy->met-HbGp. Furthermore, the denaturation process is governed by the pH value, being dependent on the protein concentration in solution.
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CURCHO, MICHEL R. da S. M. "Avaliacao de micro e macroelementos, elementos toxicos (Cd, Hg e Pb) e acidos graxos, em peixes disponiveis comercialmente para consumo em Cananeia e Cubatao, Estado de Sao Paulo." reponame:Repositório Institucional do IPEN, 2009. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9388.

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Souza, Alexandre Luiz de. "Determinação simultânia de Cd/Pb em cimento usando TI como padrão interno e de Cr/Mn em alumina por espectrometria de absorção atômica com amostragem de suspensão." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/46/46133/tde-19102007-105035/.

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O objetivo desse trabalho foi o desenvolvimento de métodos analíticos para a determinação simultânea de Cd/Pb em cimento e Cr/Mn em alumina por espectrometria de absorção atômica com atomização eletrotérmica (SIMAAS) e amostragem de suspensão. Considerando os erros de amostragem de suspensão e as condições compromissadas impostas para a determinação simultânea, foi também objetivo do trabalho estudar a aplicação de padrão interno para corrigir erros sistemático e aleatório. A viabilidade de se usar o Tl como padrão interno foi explorada na determinação de Cd e Pb em cimento. O uso do padrão interno se baseou na hipótese de que o elemento Tl deveria adsorver quantitativamente sobre as partículas do material em suspensão. Foi feito o estudo térmico dos elementos Cd, Pb e Tl em soluções aquosas e suspensões, na presença e ausência de diferentes modificadores químicos. O melhor modificador químico (5 µg Pd + 3 µg Mg) foi escolhido com base nos gráficos de correlação. As melhores temperaturas de pirólise e atomização para a determinação simultânea de Cd e Pb foram 600°C e 2000°C, respectivamente. A preparação das amostras foi feita com suspensões contendo 30 µg L-1 de Tl em 0,1 % (v v-1) de HNO3 + 0,025 % (m v-1) de Triton X-100. A avaliação da exatidão foi feita com a determinação de Cd e Pb em cimento de construção civil e dentário com análise de solução e análise de materiais de referência de sedimento marinho (MESS1 e BCSS 1) e de rio (Buffalo River, IEAEA 356). Os resultados foram concordantes em um nível de confiança de 95% (teste t-student). Os limites de detecção (LD) obtidos foram 0,14 µg L-1 (1,4pg) para o Cd e de 1,2 µg L-1 (12 pg) para Pb. As massas características foram 1,2 pg e 25 pg para Cd e Pb, respectivamente. Na determinação simultânea de Cr e Mn em alumina não foi utilizado padrão interno. O estudo envolveu a obtenção de curvas de pirólise e atomização em presença de diferentes modificadores. Estudos de interferência mostraram que 100 mg L-1 de Al provocaram aumento nos sinais analíticos dos elementos que foi eliminado com o modificador químico NaOH (0,2 mol L-1) + HF (0,4 mol L-1) combinado com 350 µg de Nb. Nessa condição as temperaturas de pirólise e atomização foram 1400°C e 2400°C, respectivamente. As suspensões de alumina foram preparadas em 2 % (v v-1) HNO3. A avaliação da exatidão foi feita com a determinação de Cr e Mn em material de referência de alumina (Alumina Reduction Grade - 699) e os resultados foram concordantes em um nível de confiança de 95% (teste t-student). Os limites de detecção (LD), estimados a partir da variabilidade de 20 medidas consecutivas de uma solução contendo 2 % (v v-1) HNO3 foram 0,11 µg L-1 (2,2 pg) para Cr e 0,17 µg L-1 (3,5 pg) para o Mn. As massas características foram 10 pg e 1,3 pg para Cr e Mn, respectivamente.
The aim of this work was the development of analytical methods for the simultaneous determination of Cd/Pb in cement and Cr/Mn in alumina by electrothermal atomic absorption spectrometry (SIMAAS) and slurry sampling. Considering the errors of slurry sampling and the imposed compromissed conditions for the simultaneous determination, it was also the aiming of this work to study the application of internal standard for the sistematic and random errors correction. The viability of using Tl as internal standard was investigated for Cd and Pb determination in cement. The internal standard aplicability was based on the hypothesis of the element Tl would have to adsorver quantitatively on the particles of the material in suspension. The thermal behaviour of Cd, Pb and Tl in aqueous solutions and suspensions was obtained in presence and absence of different chemical modifiers. The best chemical modifier (5 mg Pd + 3 mg Mg) was chosen based on correlation graphs. The pyrolysis and atomization temperatures for the simultaneous determination of Pb were 600°C and 2000°C, respectively. The sample the preparation was made with 30 mg L-1 of Tl in 0,1% (v v-1) of HNO3 + 0.025% (m v-1 of Triton X-100. The evaluation of the accuracy was made with the determination of Cd and Pb in cement, microwave extraction in acid media and analysis of marine sediment reference materials (MESS1 and BCSS 1) and river sediment (Buffalo River, IEAEA 356). The results are concordant at 95% of confidence level using Studen\'s t-test. The detention limits (LD) was 0.14 µg L-1 (1.4 pg) for Cd and 1.2 µg L-1(12 pg) for Pb. The characteristic masses were 1.2 pg and 25 pg for Cd and Pb, respectively. The simultaneous determination of Cr and Mn in alumina was done without internal standard. Pyrolysis and atomization temperaturas were obtained in presence of different modifiers. Studies of interference shown that 100 mg L-1 of Al provoked increase in the analytical signals of Cr and Mn that was eliminated with the chemical modifier NaOH (0,2 mol L-1) + HF (0,4 mol L-1) combined with 350 mg of Nb as permanent chemical modifier. In this condition pyrolysis and atomization temperatures were 1400 °C and 2400 °C, respectively. The alumina suspensions were prepared in 2% (v v-1) HNO3. The evaluation of the accuracy was made with the determination of Cr and Mn in alumina reference material (Reduction Alumina Grating - 699) and the results were concordant at 95 % of the confidence level using Student\'s t-test. The detention limits (LD) were 0.11 µg L-1 (2.2 pg) for Cr and 0.17 µg L-1 (3.5 pg) for Mn. The characteristic masses were 10 and 1.3 pg for Cr and Mn, respectively.
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Books on the topic "Cd absorption"

1

Chiffoleau, Jean-François. Dosage de certains métaux traces: (Cd, Co, Cu, Fe, Ni, Pb, Zn) dissous dans l'eau de mer par absorption atomique après extraction liquide-liquide. Plouzané, France: Ifremer, 2002.

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Anne, Grouhel, Thébaud Marie-Jo, Chiffoleau Jean-François, and Institut français de recherche pour l'exploitation de la mer., eds. Dosage de certains métaux traces: (Ag, Cd, Cr, Cu, Ni, Pb, V, Zn) dans les organismes marins par absorption atomique. France: Ifremer, 2003.

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Adsorption Analysis: Equilibria and Kinetics (Chemical Engineer Series, Volume 2). Imperial College Press, 1998.

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Adsorption Analysis: Equilibria and Kinetics (Series on Chemical Engineering, Vol 2). World Scientific Publishing Company, 1998.

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Adsorption Analysis: Equilibria and Kinetics. Imperial College Pr, 1998.

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Book chapters on the topic "Cd absorption"

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Koolhaas, M. H. C., G. van der Zwan, F. van Mourik, and R. van Grondelle. "Correlation of non-conservative CD signals, absorption spectra and dimer structure. Application to the B820-subunit." In Photosynthesis: from Light to Biosphere, 351–54. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-009-0173-5_83.

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John, Edgar, Kurt Boerlin, and Marcel J. J. Blommers. "Conformational Analysis of a Cyclic Peptide by Means of a Combined Approach of NMR, CD and UV Absorption Spectroscopy." In Fifth International Conference on the Spectroscopy of Biological Molecules, 119–21. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-1934-4_42.

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Rodger, Alison, and Matthew A. Ismail. "Introduction to circular dichroism." In Spectrophotometry and Spectrofluorimetry. Oxford University Press, 2000. http://dx.doi.org/10.1093/oso/9780199638130.003.0008.

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Circular dichroism (CD) is the ideal technique for studying chiral molecules in solution. It is uniquely sensitive to the asymmetry of the system. These features make it particularly attractive for biological systems. CD is by definition the difference in absorption, A, of left and right circularly polarized light (CPL): . . . CD = Ae − Ar . . . . . . 1 . . . CPL has the electric field vector of the electromagnetic radiation retaining constant magnitude in time but tracing out a helix about the propagation direction. Following the optics convention we take the tip of the electric field vector of right CPL to trace out a right-handed helix in space at any instant of time (1, 2). CD spectra can in principle be measured with any frequency of electromagnetic radiation. In practice, most CD spectroscopy involves the ultraviolet-visible (UV-visible) regions of the spectrum and electronic transitions, though increasing progress is being made with measuring the CD spectra of vibrational transitions using infrared radiation. We shall limit our consideration to electronic CD spectroscopy since the practical considerations for vibrational CD differ from those for electronic CD. For randomly oriented samples, such as solutions, a net CD signal will only be observed for chiral molecules (ones that cannot be superposed on their mirror images (3)). Oriented samples of achiral molecules, such as crystals, will also give a CD spectrum unless the optical axis of the sample aligns with the propagation direction of the radiation. However, such spectra are seldom useful. CD is now a routine tool in many laboratories. The most common applications include proving that a chiral molecule has indeed been synthesized or resolved into pure enantiomers and probing the structure of biological macromolecules, in particular determining the α-helical content of proteins. Figure 3 gives an example of a CD spectrum. The key points to remember are that a CD signal is observed only at wavelengths where the sample absorbs radiation, i.e. under absorption bands, and the signal may be positive or negative depending on the handedness of the molecules in the sample and the transition being studied.
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Kandra, Ranju, and Sunil Bajpai. "Wound Dressing Application of Ch/CD Nanocomposite Film." In Chitin and Chitosan - Physicochemical Properties and Industrial Applications [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.95107.

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In this work, carbon dots (CDs), obtained through microwave assisted synthesis from butane tetra carboxylic acid (BTCA), was introduced into chitosan film via simple solvent casting approach. The CDs had an average diameter of 40 to 60 nm as determined by Transmission Electron Microscopy (TEM) analysis. They possessed a zeta potential of −20.2 mV. The X-ray photon spectroscopy (XPS) confirmed presence of carboxylate groups on the surface of carbon dots. The XRD of both the plain sample Ch/CD (0) and carbon dots loaded sample Ch/CD(2) showed two crystalline sharp peaks at 14.6 and 18.1 degree, along with presence of amorphous region also. The moisture absorption data was well fitted on GAB isotherm and the profiles obtained were sigmoidal. The water vapor permeation rates for the sample Ch/CD(0) and Ch/CD(2) were found to be 1758 and 956 g/m2 /day respectively. The film samples Ch/CD(0) and Ch/CD(20 expanded 2.8 and 103 times when immersed in 4% gelatin solution for 4 h. The % hemolysis for the samples Ch/CD(0) and Ch/CD(2) was 2.12 and 1.11 respectively, thus indicating biocompatible nature of the films. In the ex-vivo mucoadhesion study, the maximum detachment force (Fmax) was 88.22 and 46.28 mN for the samples Ch/CD(0) and Ch/CD(2) respectively. Finally, both of the samples, namely Ch/CD (0) and Ch/CD(2) scored “0”, suggesting their non-cell cytotoxic nature.
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Görller-Walrand, C., and P. Vandevelde. "SINGLE CRYSTAL ABSORPTION, CD AND MCD SPECTRA OF EuAl3(BO3)4." In New Frontiers in Rare Earth Science and Applications, 359. Elsevier, 1985. http://dx.doi.org/10.1016/b978-0-12-767661-6.50090-4.

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Montalvo, Carlos, Claudia A. Aguilar, Yunuen Canedo, Alejandro Ruiz, Brenda Zermeño, Ruby S. Gines, and Rosa M. Cerón. "Quantification of Heavy Metal Levels in Sediments of the “Palizada” River in a Protected Natural Area of Southeastern Mexico." In Environmental Impact and Remediation of Heavy Metals [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.104657.

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This chapter shows the results of the determination of the levels of Copper (Cu), Iron (Fe), Magnesium (Mg), Manganese (Mn), and Cadmium (Cd) in sediments of the “Palizada River”; evaluated by atomic absorption. The results show high levels of Fe, Mg, and Mn concerning previous studies and are directly related to agricultural and livestock activities in the area. The metal-metal correlation analysis show significant values, suggesting that the generation source is the same. Some of the pollutants produced by industrial or population centers; end up in natural water bodies; by different physical processes, such as precipitation, complex formation, and others. These contaminants can bioaccumulate in aquatic organisms and reach humans through the food chain. Certain heavy metals such as cadmium (Cd) produced by human activities have been found in the oceans and the tissues of different organisms; which constitutes a risk for consumption; Cd is classified as an element that predisposes to the presence of Cancer. Therefore, the study of sediments is fundamental for determining the degree of contamination of an ecosystem.
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Moslen, Miebaka, and Chioma Hope Adiela. "Consumption Safety in Relation to Bioaccumulation of Heavy Metals in Periwinkles (Tympanotonus fuscatus) Obtained from Ogbia in the Niger Delta Region of Nigeria." In Heavy Metals - Their Environmental Impacts and Mitigation [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.94057.

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The study assessed human health risk and accumulation of heavy metals (Cd, Cu, Pb, Ni, Cr and Zn) in periwinkles (Tympanotonus fuscatus) obtained from the Niger Delta region of Nigeria. Samples were collected for six months on a monthly basis. The samples were digested according to the method described by Association of official analytical chemists and analyzed using atomic absorption spectrophotometer (AAS). Temporal variations in metal concentrations were observed with values (mgkg−1) ranging as follows Pb (2.34–6.7), Ni (0.55–2.28), Zn (0.55–11.66), Cr (0.74–3.65), Cu (1.15–3.91) and Cd (0.22–1.06). Variation in metal concentration was significantly different (p < 0.05) with metals such as Pb, Ni and Cd found to be above their respective FAO/WHO permissible limits. The estimated daily intake (EDI) of all metals examined was less than their respective reference oral doses (RFD). The target hazard quotient (THQ) non-carcinogenic and the hazard index (HI) of metals were < 1 while the hazard quotient carcinogenic (HQ) ranged between 10−6 – 10−4. The study therefore concluded gradual accumulation of metals and minimal health risk due to consumption of contaminated periwinkles in the study area.
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N. Nweke, Eucheria, Victor U. Okechukwu, Daniel O. Omokpariola, Theresa C. Umeh, and Nwanneamaka R. Oze. "Pollution Evaluation of Industrial Effluents from Consolidated Breweries: A Case Study from Benue State, Nigeria." In River Basin Management - Under a Changing Climate [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.105955.

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Industrial effluent discharged into surface water is an environmental concern, as it affects the esthetics, water quality as well as microbial and aquatic flora. Brewery effluents were analyzed for physicochemical parameters (pH, temperature, conductivity, turbidity, total dissolved solids (TDS), dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), nitrate, and sulfate, chloride) and heavy metals (As, Cd, Co, Cr, Fe, Mn, Ni, Pb, and Zn). Atomic absorption spectrophotometer was used to characterize heavy metals using standard analytical methods and compared with WHO standards. The result showed that pH (6.2–6.98), conductivity (137–273 μS/cm), chloride (31–53 mg/l), nitrate (7.53–10.72 mg/l), BOD, and DO were within the WHO limit. However, turbidity, sulfate, and phosphate were above the WHO limit. Heavy metal concentrations Cr, Ni, Pb, Mn, As, and Cd were higher than the WHO limit and vice versa for Fe, Zn, and Co. Ecological risk assessment revealed that effluent samples pose low to moderate ecological risk, for As, Pb, and Ni. Therefore, there is a need for proper treatment and continual monitoring before discharge into the environment.
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Kumari, Soni, and Amarnath Mishra. "Heavy Metal Contamination." In Soil Contamination [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.93412.

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In the era of industrialization, pollution has totally deteriorated the quality and diversity of life. Heavy metal contaminations are the major causes of environment deteriorations. The basic reasons are natural as well as anthropogenic. Chief sources of heavy metal contamination are air pollution, river sediments, sewage sludge, town waste composts, agricultural chemicals like fertilizers and pesticides, and industrial waste like factories releasing chemicals, anthropogenic activities, etc. Agricultural soils in many parts of the world are generally contaminated by heavy metal toxicity such as Cd, Cu, Zn, Ni, Co, Pb, Hg, As, etc. These are due to the long-term use of phosphate fertilizers, sewage sludge, dust from smelters, industrial waste, etc. Heavy metals in soils are detected with some specific instruments like atomic absorption spectroscopy, inductively coupled plasma, inductively coupled plasma-mass spectroscopy, and X-ray fluorescence and spectroscopy. Among all these instruments, atomic absorption spectroscopy (AAS) is the best because it gives the precise quantitative determination. AAS is a method applied for measuring the quantity of the trace elements present in the soil or any other samples.
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Aggarwal, Ankur, Tarun Verma, and Sumangal Ghosh. "Heavy Metal Residues in Milk and Milk Products and Their Detection Method." In Trends and Innovations in Food Science [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.105004.

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Milk and milk products are an essential part of the human daily diet, and their consumption is steadily increasing. Milk is regarded as a complete food because it contains all of the macronutrients including protein, carbohydrates, fat and vitamins. Milk also has a high concentration of mineral elements (metals) such as sodium, potassium, iron, calcium, magnesium, selenium, copper and zinc. They are critical for proper body growth and maintenance but excess in these metals, particularly, heavy metals cause disturbances and pathological conditions. People nowadays are concerned about food safety issues involving microbial, chemical and physical hazards. Heavy metal residues such as cadmium (Cd), lead (Pb), arsenic (As) and mercury (Hg) pose a chemical hazard. These are the main contaminants. Heavy metals are any metallic chemical elements with a relatively high density (5 g/cc) whose levels must be monitored. Atomic absorption spectroscopy can be used to estimate the heavy metal contamination in milk and milk products.
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Conference papers on the topic "Cd absorption"

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Grycuk, Teresa, Leszek Kowalczyk, and Zygmunt Morawski. "Absorption spectroscopy of the Cd 2 excimer." In High Performance Optical Spectrometry, edited by Maksymilian Pluta, Aleksandra Kopystynska, and Mariusz Szyjer. SPIE, 1993. http://dx.doi.org/10.1117/12.155649.

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Akrestina, A. S., A. S. Vishnev, R. V. Kiselyov, A. S. Surtsev, V. V. Kljajm, and M. G. Kisteneva. "Spectral Dependence of Absorption Coefficient in Bi12TiO20:Cd Crystal." In 2007 Siberian Conference on Control and Communications. IEEE, 2007. http://dx.doi.org/10.1109/sibcon.2007.371336.

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Wang, Liang, Xiao-shuang Chen, Xiao-hao Zhou, Yan Huang, Wei Lu, and Ji-jun Zhao. "Electronic property and optical absorption in amorphous semiconductor Cd." In Infrared Materials, Devices, and Applications. SPIE, 2007. http://dx.doi.org/10.1117/12.755027.

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Mishra, Bhoopesh, Elizabeth A. Haack, Igor F. Vasconcelos, Patricia A. Maurice, and Bruce A. Bunker. "XAFS Determination of Pb and Cd Speciation with Siderophores and the Metal/Siderophore/Kaolinite System." In X-RAY ABSORPTION FINE STRUCTURE - XAFS13: 13th International Conference. AIP, 2007. http://dx.doi.org/10.1063/1.2644472.

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Sung, Nark-Eon, Hyo-Yeol Park, and Min-Su Jang. "EXAFS Analysis of the Local Structure of Cd(1−x)MxTe (M=Cr, Fe, Ni)." In X-RAY ABSORPTION FINE STRUCTURE - XAFS13: 13th International Conference. AIP, 2007. http://dx.doi.org/10.1063/1.2644589.

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Mishra, Bhoopesh, Jeremy B. Fein, Maxim I. Boyanov, Shelly D. Kelly, Kenneth M. Kemner, and Bruce A. Bunker. "Comparison of Cd Binding Mechanisms by Gram-Positive, Gram-Negative and Consortia of Bacteria Using XAFS." In X-RAY ABSORPTION FINE STRUCTURE - XAFS13: 13th International Conference. AIP, 2007. http://dx.doi.org/10.1063/1.2644520.

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Tyan, Yuan-Sheng, Pranab Raychaudhuri, Kee-Chuan Pan, George R. Olin, and Fridrich Vazan. "Red Readable CD-R Media." In Symposium on Optical Memory. Washington, D.C.: Optica Publishing Group, 1996. http://dx.doi.org/10.1364/isom.1996.omb.3.

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Abstract:
Most successful recordable-CD media (CD-R) to date are based on a design suggested by Hamada et al(1). In this design the CD-R disc is constructed using a polycarbonate substrate, a lightly absorbing recording layer, and a gold reflector. The recording layer needs to have a unique set of optical properties: high n and low k. This is achieved currently by using the anomalous dispersion effect (Kramers-Kronig relation) in dyes having the trailing edge of absorption near the operating wavelength of 780 nm(2). Using this principle(3), most CD-R media today are based on two classes of dye, cyanine and phthalocyanine.
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Wu, Xi, Shaohua He, Xinjia Huang, and Jimin Tian. "Absorption of Cd II with Bamboo Charcoal Modified by Succinic Acid." In 2015 4th International Conference on Sensors, Measurement and Intelligent Materials. Paris, France: Atlantis Press, 2016. http://dx.doi.org/10.2991/icsmim-15.2016.50.

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Pinzani, M. Caterina Camerani, Britt-Marie Steenari, and Oliver Lindqvist. "Direct Determination of Cadmium Speciation in MSW and Biomass Single Fly Ash Particles Using SR Based µ-XR Spectroscopy Techniques." In 17th International Conference on Fluidized Bed Combustion. ASMEDC, 2003. http://dx.doi.org/10.1115/fbc2003-021.

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Cadmium is a toxic metal causing environmental concern in connection with utilization and land filling of ash. Knowledge about the chemical associations of Cd in ash is fundamental in the understanding of its solubility and leachability from the ash. In the work presented here, the content, distribution and chemical forms of Cd on/in individual Municipal Solid Waste (MSW) and biomass fly ash particles have been investigated in situ by Synchrotron Radiation induced μ-X-ray fluorescence, absorption spectrometry (XAS) and fluorescence tomography. These X-ray micro-beam techniques can be used to reveal spatially resolved information about structural and chemical properties of particles. The use of an excitation energy of 27 keV made it possible to detect trace metals, such as Cd at ppm levels, but also other elements, like Ca, K, Cl and Br. Absorption spectra of Cd in the energy range around the absorption edge of Cd (26.71 keV) were recorded for micron-sized spots of ash particles. Fluorescence tomography was then use to establish if Cd compounds are situated on the particle surface (i.e. most prone to leaching) or at some depth within the particle, where they might be more shielded from chemical attack by water. The measurements indicated Cd to be preferably concentrated in some small areas (“hot-spots”) with high concentration (up to 200 ppm) in MSW fly ash particles and in a homogeneous distribution over the whole particle surface in the case of biomass. Comparisons of XAS spectra of fly ashes and reference compounds showed Cd to be present in the oxidation state +2 and mainly as CdSO4, CdO and CdCl2. Although previous studies have indicated Cd to be enriched in the smaller-size ash particles, in this study Cd was found to be reasonably well distributed throughout all the particle sizes investigated. Based on the results obtained, possible reaction mechanisms involving Cd are suggested.
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Liang, Xie-qin, Yu-qin Guo, Xie-rong Hu, Jia-xiong Fang, and Guo-sen Xu. "Absorption Coefficient Of N-Type Hg 1-x Cd x Te Samples." In SPIE 1989 Technical Symposium on Aerospace Sensing, edited by Eustace L. Dereniak and Robert E. Sampson. SPIE, 1989. http://dx.doi.org/10.1117/12.960668.

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