Search results for " Contamination"

Accurate Prediction of Hyperfine Coupling Tensors for Main Group Elements Using a Unitary Group Based Rigorously Spin-Adapted Coupled-Cluster Theory

2019

We present the development of a perturbative triples correction scheme for the previously reported unitary group based spin-adapted combinatoric open-shell coupled-cluster (CC) singles and doubles (COS-CCSD) approach and report on the applications of the newly developed method, termed "COS-CCSD(T)", to the calculation of hyperfine coupling (HFC) tensors for radicals consisting of hydrogen, second- and third-row elements. The COS-CCSD(T) method involves a single noniterative step with [Formula: see text] scaling of the computational cost for the calculation of triples corrections to the energy. The key feature of this development is the use of spatial semicanonical orbitals generated from st…

Spin-restricted open-shell coupled-cluster theory for excited states

2000

Using a linear-response approach, the recently introduced spin-restricted coupled-cluster (SR-CC) theory is extended to the treatment of excited states of high-spin open-shell molecules. Explicit equations are given within the usual singles and doubles approximation and our implementation (within an existing spin–orbital code) is described. It is shown that in SR-CC theory, due to spin constraints, the spin-expectation value for the excited states calculated as corresponding energy derivatives always corresponds to the exact value. In addition, the SR-CC singles and doubles (SR-CCSD) approach is extended to include also the so-called pseudotriple excitations (best described as double excita…

SuperK-Gd Physics Potential

2018

In this section, all the measurements and potential searches that SuperK-Gd would be able to performed, are addressed. This section takes into account all the advantages of the 80% efficiency neutron tagging technique using gadolinium, but also the drawbacks that the inclusion of radioactive contamination could have in these measurements.

Shoot accumulation of several trace elements in native plant species from contaminated soils in the Peruvian Andes

2012

Abstract Metal mining gives access to very important resources but contributes to severe and diverse environmental problems. Until recently, little has been known about the remediation of mining sites in Latin America using metallophytes. The present study was designed to identify and characterize spontaneously growing heavy metal tolerant plant species in the area around the polymetallic Carolina mine in Hualgayoc (Cajamarca, Peru). The aim was to find species that are potentially useful for phytoremediation. Plants and soils were sampled and analysed for concentrations of As, Fe, Mn, Pb, Zn and Ti. The Translocation Factor (TF) and the Bioaccumulation Factor (BF) were determined and used …

Role of yeasts in table olive production

2008

Table olives are a traditional fermented vegetable of the Mediterranean countries, but their production and consumption are now spread all around the world. Yeasts can play a double role in this food. They are present throughout the fermentative process and it is generally accepted that they can produce compounds with important organoleptic attributes determining the quality and flavour of the final product. However, yeasts can also be spoilage microorganisms in olive fermentation/storage and packing causing gas pockets, swollen containers, cloudy brines and off-flavours and off-odours. Candida boidinii, Debaryomyces hansenii, Pichia anomala, P. membranifaciens, Rhodotorula glutinis and Sac…

Metal Oxides for Removal of Arsenic Contaminants from Water

2021

Arsenic (As), one of the highest harmful pollutants found in drinking/groundwater, is owing to have unfavourable impacts, for example, skin disease, on human health. The new Environmental Protection Agency (EPA) assigned the maximum contaminations of arsenic in groundwater is 10μg/L, and several drinking water plants are needing extra treatment to accomplish this standard. In recent years, several researchers have been attempting to discover practical and expendable adsorbents for some water filtration systems that are utilized in many arsenic endemic territories. Metal oxide-based adsorbents had been proved to be the best strategies for arsenic expulsion/removal. This chapter reviews the r…

Geographical and ecological outline of metal(loid) accumulating plants in Italian vascular flora

2018

The decontamination of heavy metal polluted soils is one of the major challenges that our industrialized world has to face. Remediation technologies are being developed and employed in order to reduce the potential hazards of metal and metalloid contamination. Plants capable of uptaking metals and metalloids in their tissues can be an effective tool to remove such pollutants from contaminated soils. The use of this plant-driven process (Phytoremediation) requires the knowledge of the right phytoextractors to use when facing different types of contamination. The aim of this paper is to provide an inventory of phytoextractors that can be used in Phytoremediation procedures in Italy. The check…

Evaluation of the Soil Contamination of Tangier (Morocco) by the Determination of BTEX, PCBs, and PAHs

2009

Benzene, toluene, ethylbenzene, and xylenes (BTEX), twelve polycyclic aromatic hydrocarbons (PAHs) and seven polychlorinated biphenyls (PCBs), were selected as pollutants to evaluate the contamination of soils in the urban and industrial areas of Tangier (Morocco). PAHs and PCBs were determined by gas chromatography-mass spectrometry (GC-MS) after a microwave-assisted extraction (MAE) and gel permeation chromatography (GPC) clean-up. BTEX were directly determined by head-space GC-MS. Results obtained in this study show the presence of high levels of BTEX and PAHs in the soil near the urban waste deposit. However, the analysis of pollutants in the other sampling sites provided comprehensive …

REDUCED UPTAKE OF Cd AND Pb BY Miscanthus sinensis x giganteus CULTIVATED ON POLLUTED SOIL AND ITS USE AS BIOFUEL

2013

Soil plate bioassay: an effective method to determine ecotoxicological risks.

2010

Heavy metals have become one of the most serious anthropogenic stressors for plants and other living organisms. Having efficient and feasible bioassays available to assess the ecotoxicological risks deriving from soil pollution is necessary. This work determines pollution by Cd, Co, Cr, Cu, Ni, Pb, V and Zn in two soils used for growing rice from the Albufera Natural Park in Valencia (Spain). Both were submitted to a different degree of anthropic activity, and their ecotoxicological risk was assessed by four ecotoxicity tests to compare their effectiveness: Microtox test, Zucconi test, pot bioassay (PB) and soil plate bioassay (SPB). The sensitivity of three plant species (barley, cress and…