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531.
A worst-case simulation of the mass-balance for metals in the waste deposited during 1 year and the levels of cadmium (Cd), lead (Pb), mercury (Hg), chromium (Cr) and iron (Fe) in the leachate was calculated for four sanitary landfills in Western Norway. Estimates of the levels of metal content in mixed municipal solid waste (MSW) were found by using recent literature values calculated in a mass-balance study at a Norwegian waste incinerator plant. Leachate from the landfills were sampled and analyzed monthly during 1 year, and from these measurements the total annual discharge of the selected metals through the leachate was determined. The levels of the measured heavy metals in the leachate were low. For Cd less than 0.06%, for Pb less than 0.01% and for Hg less than 0.02% of the estimated year's deposited mass of metals were leached from the landfills during the year of investigation. The high retention of these metals are most likely due to sulfide precipitation, but also due to the immobile condition of the metals in their original deposited solid state (plastics, ceramics, etc.). The percentage of Cr leached was relatively higher, but less than 1.0% per year. The mass balance of Fe suggests that this element is more mobile under the prevailing conditions. The percentage of Fe leached varied and was estimated to be between 1.9% and 18%. The present study clearly supports the theory that MSW only to a small extent will lead to discharge of metals if deposited at well-constructed sanitary landfills with top layers. 相似文献
532.
The full Mueller matrix was measured to obtain the polarization state of the scattered light for a variety of algae with different shapes, wall compositions, sizes, and refractive indices. The experimental setup was a multiple laser Mueller matrix ellipsometer, by which measurements were performed for scattering angles from 16° to 160° sampled at every second degree for wavelengths of 473?nm and 532?nm. Previously, the polarization of light scattered from microalgae was investigated only for a few species, and the Mueller matrix was found to have little variation between the species. In our work a total of 11 algal species were investigated, representing diatoms, dinoflagellates, coccolithophorids, green algae, and a cryptophyte. The selection of species was made to obtain high variability in shape, size, cell wall, and refractive index. As in previous investigations, very small variations were found between species for most of the Mueller matrix elements, but noticeable variations were found for M(11), (M(12)+M(21))/2 and (M(33)+M(44))/2. 相似文献
533.
Low‐fat Cheddar cheese made using microparticulated whey proteins: Effect on yield and cheese quality 下载免费PDF全文
Jessica A Stankey Yanjie Lu Abdelmoneim Abdalla Selvarani Govindasamy‐Lucey John J Jaeggi Bente Ø Mikkelsen Kenneth T Pedersen Claus B Andersen 《International Journal of Dairy Technology》2017,70(4):481-491
Influence of different levels (0, 0.15, 0.35 or 0.50%) of microparticulated whey protein (MWP) on yield and quality of low‐fat (~7.3 g/100 g) Cheddar cheese was investigated. MWP improved cheese yield due to the water‐binding ability of denatured whey protein. MWP addition decreased meltability but improved the textural properties beneficial for shredding and slicing, by decreasing sensory firmness. The results emphasise the role of MWP as an inert filler within cheese matrix, in improving cheese yield and creating a softer texture without compromising the sensory or overall quality of cheese, even with moisture increases in 0.35 or 0.50% MWP cheeses. 相似文献
534.
Dr. Davide Cirillo Shahin Sarowar Prof. Per Øyvind Enger Prof. Hans-René Bjørsvik 《ChemMedChem》2021,16(17):2650-2668
The xCT antiporter is a cell membrane protein involved in active counter-transportation of glutamate (outflux) with cystine (influx) over the human cell membrane. This feature makes the xCT antiporter a crucial element of the biosynthesis of the vital free radical scavenger glutathione. The prodrug sulfasalazine, a medication for the treatment of ulcerative colitis, was previously proven to inhibit the xCT antiporter. Starting from sulfasalazine, a molecular scaffold jumping followed by SAR-assisted design and synthesis provided a series of styryl hydroxy-benzoic acid analogues that were biologically tested in vitro for their ability to decrease intracellular glutathione levels using four different cancer cell lines: A172 (glioma), A375 (melanoma), U87 (glioma) and MCF7 (breast carcinoma). Depletion of glutathione levels varied among the compounds as well as among the cell lines. Flow cytometry using propidium iodide and the annexin V marker demonstrated minimal toxicity in normal human astrocytes for a promising candidate molecule (E)-5-(2-([1,1′-biphenyl]-4-yl)vinyl)-2-hydroxybenzoic acid. 相似文献
535.
A large number of studies have demonstrated that the proportion of home-owners in a region tend to be positively associated with the unemployment levels in that region. In this paper, we introduce a missing piece of explaining this commonly found pattern. By analysing individual-level population register data on Sweden, we jointly examine the effects of micro- and macro-level home-ownership on individuals’ unemployment. The findings indicate that even though home-owners have a lower probability of being unemployed, there is a penalty for both renters and home-owners on unemployment in regions with high home-ownership rates. Differences in mobility patterns cannot explain this pattern. However, when labour market size is considered, the higher probability of unemployment in high home-owning regions is drastically reduced. This suggests that high home-ownership regions tend to coincide with small labour markets, affecting the job matching process negatively. 相似文献
536.
Vadon Mathieu Sortland Øyvind Tangstad Merete Chichignoud Guy Delannoy Yves 《Metallurgical and Materials Transactions B》2018,49(6):3330-3342
Metallurgical and Materials Transactions B - The present study focuses on a specific step of the metallurgical path of purification to provide solar-grade silicon: the removal of boron through the... 相似文献
537.
The kinetics of aluminium deposition from NaClAlCl3 and NaClKClAlCl3 melts (cAlCl3 < 0.4 mol%) was studied by linear sweep voltammetry and potential step amperometry. The reduction of AlCl3 on tungsten and aluminium electrodes was found to be diffusion controlled. The diffusion coefficients of AlCl3 were: 3.5 × 10?5 cm2 s?1 at 820°C in NaClAlCl3, 2.7 × 10?5cm2s?1 at 825°C, and 2.1 × 10?5cm2s?1 at 705°C in KClNaClAlCl3. The rate constant for AlCl3 reduction at these conditions was found to be in the order of 0.2 cm s?1, in good agreement with extrapolated literature data. 相似文献
538.
G Johannesdottir J Gudmundsson JT Bergthorsson A Arason BA Agnarsson G Eiriksdottir OT Johannsson A Borg S Ingvarsson DF Easton V Egilsson RB Barkardottir 《Canadian Metallurgical Quarterly》1996,56(16):3663-3665
Studies on Icelandic breast cancer families have shown that most of them segregate a 999del5 BRCA2 mutation. Here, we report the frequency of the 999del5 BRCA2 mutation in an Icelandic control population and four different groups of cancer patients diagnosed with (a) breast cancer; (b) ovarian cancer; (c) prostate cancer (patients younger than 65 years); and (d) other cancer types. The proportions of individuals carrying the mutation were 0.4% in the control population and in the patient groups 8.5%, 7.9%, 2.7%, and 1.0%, respectively. Our results indicate that BRCA2 confers a very high risk of breast cancer and is responsible for a substantial fraction of breast and ovarian cancer in Iceland, but only a small proportion of other cancers. 相似文献
539.
Oddvin Reiso Hilde-Gunn Øverlie Nils Ryum 《Metallurgical and Materials Transactions A》1990,21(6):1689-1695
When up-quenching an Al-4.2 wt pct Cu alloy which has been equilibrated at 450 °C to a temperature at or above the eutectic
temperature of 547 °C, liquid drops are found to form. Inside the matrix grains they have a globular shape, while they have
a lenticular shape with a low dihedral angle when formed on grain boundaries. It is demonstrated metallographically that drops
are formed by the melting of the Al2Cu phase particles together with the surroundingα matrix to form a liquid of chemical composition around the eutectic composition. On prolonged annealing, the drops are dissolved
in theα matrix. The kinetics of this dissolution reaction of the drops, as well as the dissolution of Al2Cu phase particles at a temperature below 547 °C, is studied in some detail and compared with a simple mathematical model.
Also, the thermodynamics of the melting and dissolution reactions are discussed by means of a free-energy diagram. 相似文献
540.