Health & Environmental Research Online (HERO)


Trimethylbenzenes (TMB)


5,559 References Were Found:

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

The impact of mining activities on the hypersaline Mar Menor lagoon

Authors: Dassenakis, M; Garcia, G; Diamantopoulou, E; Girona, JD; Garcia-Marin, EM; Filippi, G; Fioraki, V HERO ID: 857817

[Less] Mar Menor lagoon is one of the largest hypersaline coastal lagoons in the Mediterranean Sea. The lagoon . . . [More] Mar Menor lagoon is one of the largest hypersaline coastal lagoons in the Mediterranean Sea. The lagoon is threatened by environmental degradation due to the urban growth around it, the intensive agriculture in its watershed and the remains of mining activities in the nearby Cartagena-La Uninarea. The present study aims at estimating the level sof zinc and lead in the water column, sediments and marine flora and fauna of Mar Menor lagoon. The ranges of the total concentrations in the water column were 9.36-28.7 g/L for Zn, 1.61-12.6 g/L for Pb and 3.01-29.70 g/L for Mn. Zinc was mostly found in the dissolved phase (70%) whereas lead and manganese in the suspended phase (63-76%). Highest values were measured at stations closer to streams flowing trough drainage basins including agricultural zone and the mining remains. Concerning sediments, the values were very high especially at the southern part, indicating transport of suspended matter from currents. The metal content in the sediments is higher than the content in particulate matter and there is an increased bioavailability of Zn and Pb. Zinc and lead were measured in the thallus of four marine flora species. Maximum zinc concentration was measured in Cymodosea nodosa (132 g/g) and maximum lead in Acetabularia acetabulum (93.5 g/g) in samples from the southern lagoon. From the two benthic fauna species studied, it was observed that heavy metals accumulate mostly in the animal flesh. The highest concentration of Zn and Pd was measured in the flesh of the mollusk Ostrea edullis with values of 1,856 and 51.0 g/g respectively. These values reveal the effect of heavy metal pollution in the lagoon ecosystem. 2010 Desalination Publications.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Impacts of point source and diffuse metal and nutrient loading on three northern boreal lakes

Authors: Mkinen, J; Kauppila, T; Loukola-Ruskeeniemi, K; Mattila, J; Miettinen, J HERO ID: 858562

[Less] A geochemical-paleolimnological study was conducted to investigate human influences on three lakes (Nuasjrvi, . . . [More] A geochemical-paleolimnological study was conducted to investigate human influences on three lakes (Nuasjrvi, Jormasjrvi and Kolmisoppi) located in an area with high background levels of metals and sulphur in bedrock and till overburden. Accordingly, background concentrations of Co, Fe, Mg, Mn, Ni and Zn were above average in sediments of the study lakes. The land use-related erosion and transport of particulate matter into Lake Nuasjrvi started as early as in the seventeenth century, while increased inputs to Lake Jormasjrvi date to the eighteenth century and Lake Kolmisoppi to the 1970s and 1980s. Local tills and fine-grained sediments are the source of the particles and hydraulic sorting has resulted in elevated sediment concentrations of Ca, Cr, Cu, K, Mg, Na and Ni. At the same time, sedimentation of carbon and autochthonous phases has decreased, leading to low concentrations of Co, Fe and Mn in the erosion-associated sediment layers in Nuasjrvi and Kolmisoppi. Despite the geochemical changes, no marked eutrophication of the lakes could be detected with diatom-based nutrient reconstructions during the early land-use period. Elevated amounts of sulphur and chalcophilic elements were deposited throughout the study area during the 1970s and 1980s. In Lake Nuasjrvi combination of the elements is associated with the Lahnaslampi mine and the difference in the sulphide degradation rate is reflected as a sequence of element mobility and sedimentation in the order 1) S, and 2) Co, Ni, Cu, Zn, Cd and Sb. Sulphur, Cu, Ni, Pb and Zn enrichment in the other two lakes is related to other land uses and to atmospheric deposition. In addition to sulphur and metals, these most recent inputs from the catchment have caused nutrient enrichment in all three study lakes, most notably in the lowest-lying Lake Nuasjrvi. This lake has the highest percentage of fine-grained soils in its catchment and also suffers from point source nutrient inputs. In addition, metals (Ni) had a signal in diatom assemblages in Lake Nuasjrvi that was statistically independent of eutrophication (N:C) but inseparable from mineral matter inputs (K). 2009 Elsevier B.V. All rights reserved.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Comparative multinuclear magnetic resonance spectroscopic study of transition metal (Cr, W and Mn) mesitylene tricarbonyls and transition metal (Ru and Co) carbonyl clusters


The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Substitutional photochemistry of Ru (eta^6-mes)^2~2^2 and Ru(eta^6-mes) (CH~3CN)^2~3^+ (mes = 1,3,5-trimethylbenzene)


Journal Article
Journal Article

Temperature resolved FTIR spectroscopy of Cr2+/SiO2 catalysts: acetylene and methylacetylene oligomerisation

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As is well known, the Cr2+/SiO2 system is an efficient catalyst for ethylene . . . [More]

As is well known, the Cr2+/SiO2 system is an efficient catalyst for ethylene polymerisation already at RT (even if in the industrial process the running temperature is ~380 K). For this reason it is the ideal system for in situ spectroscopic investigations on a genuinely working catalyst (Adv. Catal., 2001, 46, 265). Many questions are still uncertain as to the initiation, propagation and termination steps of the polymerisation mechanism. On a pre-reduced sample polymerisation commences very quickly and there is no way to record initial stages. When the experiments are performed at RT the phenomenon is too fast and IR spectroscopy, even in the time-resolved mode, failed up to now in the identification of the species formed during the initiation of the ethylene polymerisation step on the Cr2+/SiO2 Phillips catalyst. We present results related to time-resolved FTIR spectroscopy at variable temperature of acetylene and methylacetylene oligomerisation on a model Phillips catalyst. These experiments have been highly informative on the nature of the active sites because we have observed that acetylene and methylacetylene result in the immediate formation of benzene and 1,3,5-trimethylbenzene, respectively, without the evidence of any measurable intermediate product. This implies that the active Cr sites are able to coordinate simultaneously three monomers and thus must exhibit a high unsaturative coordination. The results of these experiments could be an insight of chromium species active in the Phillips catalyst.



The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Unexpected formation of clusters with a nortricyclene-containing carborane ligand, 1-(6-arene)-3-(C7H9CH2O)-isonido-1,2,4-RuC2B8H9, in the reaction of 1,1,3-(PPh3)3-1-H-1,2,4-RuC2B8H9 with 2-(hydroxymethyl)norbornadiene in arene solvents

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Heating of 1,1,3-(PPh3)3-1-H-1,2,4-RuC2B8H9 . . . [More]

Heating of 1,1,3-(PPh3)3-1-H-1,2,4-RuC2B8H9 with 2-(hydroxymethyl)bicyclo[2.2.1]hepta-2,5-diene in arene solvents (benzene, toluene, or mesitylene) unexpectedly afforded the ruthenium arene complexes 1-(6-arene)-3-(C7H9CH2O)-isonido-1,2,4-RuC2B8H9 containing the nortricyclene fragment in the carborane ligand.



The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Chemistry of bis(pentafluorobenzyl) phosphines and phosphine oxides. Single-crystal X-ray diffraction study of eta^6-mesitylene-dichloro-[bis(pentafluorobenzyl)phosphinous acid]-ruthenium(II) and of 1,2-bis(pentafluorophenyl)ethane


The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Mechanism and timing of Pb transport from subducted oceanic crust and sediment to the mantle source of arc lavas

Authors: Regelous, M; Gamble, JA; Turner, SP HERO ID: 857572

[Less] New high-precision (double-spike) Pb isotope analyses of lavas from Tafahi and Niuatoputapu, the northernmost . . . [More] New high-precision (double-spike) Pb isotope analyses of lavas from Tafahi and Niuatoputapu, the northernmost islands of the Tonga-Kermadec Island Arc, are used to examine the source of Pb in these samples, and the relative timing of Pb addition from the subducting oceanic crust and subducting sediment. Lavas from these islands have distinctive, radiogenic Pb isotope compositions, which are inherited from the basaltic crust of the subducting Louisville Seamount Chain on the Pacific Plate. The subducting oceanic plate and the overlying upper mantle beneath northern Tonga therefore have very different Pb isotope compositions, allowing the proportion of Pb derived from each of these sources, and from subducting sediment to be estimated. We show that between 42% and 90% of the Pb in northern Tonga lavas is derived from the basaltic crust of the subducting Louisville Seamount Chain. The dominant source of mantle Pb in arc lavas (at least in northern Tonga), is therefore subducted basaltic oceanic crust, rather than the overlying mantle wedge. The orientation of the Pb isotope arrays constrain the relative timing of Pb addition from these different sources, and show that sediment Pb must be mixed with the upper mantle before Pb from the subducted oceanic crust is added during a separate event. This observation is consistent with the results of experimental studies, which suggest that altered oceanic crust and sediment are likely to lose Pb by dehydration or melting at different depths. Melting of sediment at depths >120km, followed by migration of these melts to shallower levels within the overlying mantle, where Pb-bearing fluids derived from dehydration of oceanic crust trigger mantle melting, could explain the observed mixing relationships. Mass balance calculations show that the Pb flux into the arc magma source corresponds to the amount of Pb contained in the uppermost 67 to 143m of the subducting basaltic crust of the Louisville Seamount Chain. If this minimum estimate is representative of subduction zones worldwide, where 7km thick oceanic crust containing 0.5ppm Pb is subducted, then the average Nd/Pb ratio of the oceanic crust that is recycled into the deep mantle is decreased by at least 3.5% as a result of subduction. 2010 Elsevier B.V.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Interspecific variation of heavy metal concentrations in the different tissues of tropical intertidal gastropods from Malaysia

Authors: Edward, FB; Yap, CK; Tan, SG HERO ID: 725254

[Less] The present study aims to determine the concentrations of Cd, Cu, Fe, Ni, Pb, and Zn in the different . . . [More] The present study aims to determine the concentrations of Cd, Cu, Fe, Ni, Pb, and Zn in the different tissues of five species of tropical intertidal gastropods from Malaysia. Each of the species have organs/tissues that highly accumulated certain metals. For Cu, the mantles of Cerithidea obtusa, Pugilina cochlidium, and Murex trapa; and the digestive caeca of Thais sp. and Chicoreus capucinus highly accumulated Cu. The shells of Chi. capucinus and M. trapa, the digestive caeca of P. cochlidium, and the digestive glands of Thais sp. and Chi. capucinus highly accumulated Cd. The tentacles and the digestive caeca of Cer. obtusa and P. cochlidium, respectively, highly accumulated Zn, the digestive glands of Thais sp., Chi. capucinus, and M. trapa also highly accumulated Zn. The shells of most of the gastropods accumulated high levels of Pb and Ni. The opercula of most of the gastropods, besides the digestive glands for Thais sp., accumulated high levels of Fe. The present study on interspecific variations of heavy metals in gastropods provided information on differences of metal distributions in the different tissues, which could be useful in proposing potential tissues as better biomonitoring tools of heavy metal bioavailabilities in the coastal waters of Peninsular Malaysia. 2010 Taylor & Francis.