A New Gas-Liquid Interphase Reactor

A first-order differential equation describes the dynamic response of many continuous air sampling instruments: C_t = C_i + p(dC_i/dt), where C_t is true concentration, C_i is indicated concentration, p is the time constant, and t is time. The time constant, lag time, delay time, and response time are all functions of the volume and flow through the sensor reservoir. All of them can be expressed by the same general equation: t = k₃V/Q, where t is the selected time variable, k₃ is a constant appropriate to the particular system and selected time variable, V is sensor reservoir volume, and Q is the flow rate through the reservoir. The time constant is the time a sampler takes to indicate 63.2 percent of its final response. Select time constants equal to about half of the shortest desired averaging time. Solve the second equation for the reagent flow to give the desired time constant. Selection of such a time constant eliminates spurious “noise” produced by a fast-responding system. It also provides values within 5 percent of true for atmospheres that change markedly between successive intervals. If a slow-responding system must be used, use the first equation to increase apparent response time. A digital computer can be programmed to automatically correct all measured values. Similarly, analog circuitry can be installed in an air sampling instrument to increase or decrease response time. The analog circuitry to increase response time will continuously solve and plot the first equation.     

Pharmaceutical and personal care products in groundwater, subsurface drainage, soil, and wheat grain, following a high single application of municipal biosolids to a field

Dewatered municipal biosolids (DMBs) were applied to a field at a rate of ~22 Mg dw ha(-1) in October 2008. Pharmaceuticals and personal care products (PPCPs) were monitored in groundwater, tile drainage, soil, DMB aggregates incorporated into the soil post-land application, and in the grain of wheat grown on the field for a period of ~1 year following application. Over 80 PPCPs were analyzed in the source DMB. PPCPs selected for in-depth monitoring included: antibiotics (tetracyclines, fluoroquinolones), bacteriocides (triclosan, triclocarban), beta-blockers (atenolol, propranolol, metaprolol), antidepressants (fluoxetine, citalopram, venlafaxine, sertraline), antifungals (miconazole), analgesics (acetaminophen, ibuprofen) and anticonvulsants (carbamazepine). PPCPs in tile were observed twice, ~3 weeks and 2 months post-application. Of all PPCPs measured in tile drainage, only carbamazepine, ibuprofen, acetaminophen, triclosan, triclocarban, venlafaxine, and citalopram were detected (5-74 ng L(-1)). PPCPs were not detected in groundwater >2 m depth below the soil surface, and concentrations above detection limits at 2 m depth were only observed once just after the first rain event post-application. In groundwater, all compounds found in tile, except carbamazepine, acetaminophen and citalopram, were detected (10-19 ng L(-1)). PPCPs were detected in DMB aggregates incorporated in soil up to 1 year post-application, with miconazole and fluoxetine having the lowest percent reductions over 1 year (~50%). For several compounds in these aggregates, concentration declines were of exponential decay form. No PPCPs were detected in the grain of wheat planted post-application on the field. No PPCPs were ever detected in water, soil or grain samples from the reference plot, where no DMB was applied.     

Phytoestrogens and mycotoxins in Iowa streams: an examination of underinvestigated compounds in agricultural basins

This study provides the first broad-scale investigation on the spatial and temporal occurrence of phytoestrogens and mycotoxins in streams in the United States. Fifteen stream sites across Iowa were sampled five times throughout the 2008 growing season to capture a range of climatic and crop-growth conditions. Basin size upstream from sampling sites ranged from 7 km2 to > 836,000 km2. Atrazine (herbicide) also was measured in all samples as a frame-of-reference agriculturally derived contaminant. Target compounds were frequently detected in stream samples: atrazine (100%), formononetin (80%), equol (45%), deoxynivalenol (43%), daidzein (32%), biochanin A (23%), zearalenone (13%), and genistein (11%). The nearly ubiquitous detection of formononetin (isoflavone) suggests a widespread agricultural source, as one would expect with the intense row crop and livestock production present across Iowa. Conversely, the less spatially widespread detections of deoxynivalenol (mycotoxin) suggest a more variable source due to the required combination of proper host and proper temperature and moisture conditions necessary to promote Fusarium spp. infections. Although atrazine concentrations commonly exceeded 100 ng L(-1) (42/75 measurements), only deoxynivalenol (6/56 measurements) had concentrations that occasionally exceeded this level. Temporal patterns in concentrations varied substantially between atrazine, formononetin, and deoxynivalenol, as one would expect for contaminants with different source inputs and processes of formation and degradation. The greatest phytoestrogen and mycotoxin concentrations were observed during spring snowmelt conditions. Phytoestrogens and mycotoxins were detected at all sampling sites regardless of basin size. The ecotoxicological effects from long-term, low-level exposures to phytoestrogens and mycotoxins or complex chemicals mixtures including these compounds that commonly rake place in surface water are poorly understood and have yet to be systematically investigated in environmental studies.     

Uphill permeation of Cr(VI) using Hostarex A327 as ionophore by membrane-solvent extraction processing

The transport of chromium by the emulsion pertraction technology (EPERT) using Hostarex A327 (tertiary amine) as a carrier has been investigated. The permeation of the metal is studied as a function of various experimental variables: hydrodynamic conditions, concentration of Cr(VI) and HCl in the source phase, carrier concentration and diluent in the organic phase, strippant concentration in the stripping phase and support characteristics of the membrane. The mass transfer coefficient and the thickness of the aqueous source boundary layer were estimated from the experimental data. Furthermore, the selectivity of the Hostarex A327-bases EPERT towards different metal ions and the behaviour of the system against other carriers are presented.     

Distribution and relationship between antimicrobial resistance genes and heavy metals in surface sediments of Taihu Lake, China

Heavy metals, pharmaceuticals, and other wastes released into the environment can significantly influence environmental antibiotic resistance. We investigated the occurrence of 22 antimicrobial resistance genes(ARGs) and 10 heavy metal concentrations, and the relationship between ARGs and heavy metals in surface sediment from seven sites of Lake Taihu. The results showed significant correlations(p 0.05) between sediment ARG levels,especially for tetracycline and sulfonamides(e.g., tet(A), tet(D), tet(E), tet(O), sul1, sul2 and int-1) and specific heavy metals(Fe, Mn, Cr, Cu, Zn, among others) in the Lake. In the surface sediments, heavy metals showed an interaction with resistance genes, but the strength of interaction was diminished with increasing depth. For most of the heavy metals, the concentration of elements in the top sediments was higher than that in other depths.Tetracycline resistance genes(tet(A), tet(B), tet(D), tet(E) and tet(O), β-lactam resistance genes(SHV, TEM, CTX, OXA and OXY) and sulfonamide resistance genes(sulA, sul1, sul2, sul3 and int-1) were detected. They showed a trend which inferred a statistically significant increase followed by decreases in the relative abundance of these ARGs(normalized to 16 S rRNA genes) with increasing depth. This study revealed that tet(A), tet(O), TEM, OXY, int-1, sul1 and sul3 were widespread in surface sediments with high abundance, indicating that these genes deserve more attention in future work.     

Juvenile morphology: A clue to the origins of the most mysterious of mysticetes?

The origin of the pygmy right whale (Caperea marginata) has long been one of the most vexing conundrums of marine mammal evolution. The extremely disparate skeletal structure of Caperea and a patchy fossil record have left morphology and molecules at odds: whereas most morphological analyses ally Caperea with right whales (Balaenidae), most molecular studies instead suggest a close relationship with rorquals (Balaenopteridae) and grey whales (Eschrichtiidae). The morphological evidence supporting a Caperea-balaenid clade consists of several shared features of the skull and mandible, as traditionally observed in adult individuals. Here, we show that at least two of these features, the ascending process of the maxilla and the coronoid process, arise from substantially different precursors early during ontogeny and therefore likely do not represent genuine synapomorphies. Both of these juvenile morphologies have adult counterparts in the fossil record, thus indicating that the ontogenetic variation in the living species may be a genuine reflection of differing ancestral states. This new evidence contradicts previous morphological hypotheses on the origins of Caperea and may help to reconcile morphological and molecular evidence.     

High-field 1H T1 and T2 NMR relaxation time measurements of H2O in homeopathic preparations of quartz, sulfur, and copper sulfate

Quantitative meta-analyses of randomized clinical trials investigating the specific therapeutic efficacy of homeopathic remedies yielded statistically significant differences compared to placebo. Since the remedies used contained mostly only very low concentrations of pharmacologically active compounds, these effects cannot be accounted for within the framework of current pharmacology. Theories to explain clinical effects of homeopathic remedies are partially based upon changes in diluent structure. To investigate the latter, we measured for the first time high-field (600/500 MHz) ¹H T₁ and T₂ nuclear magnetic resonance relaxation times of H₂O in homeopathic preparations with concurrent contamination control by inductively coupled plasma mass spectrometry (ICP-MS). Homeopathic preparations of quartz (10c–30c, n = 21, corresponding to iterative dilutions of 100⁻¹⁰–100⁻³⁰), sulfur (13x–30x, n = 18, 10⁻¹³–10⁻³⁰), and copper sulfate (11c–30c, n = 20, 100⁻¹¹–100⁻³⁰) were compared to n = 10 independent controls each (analogously agitated dilution medium) in randomized and blinded experiments. In none of the samples, the concentration of any element analyzed by ICP-MS exceeded 10 ppb. In the first measurement series (600 MHz), there was a significant increase in T₁ for all samples as a function of time, and there were no significant differences between homeopathic potencies and controls. In the second measurement series (500 MHz) 1 year after preparation, we observed statistically significant increased T₁ relaxation times for homeopathic sulfur preparations compared to controls. Fifteen out of 18 correlations between sample triplicates were higher for controls than for homeopathic preparations. No conclusive explanation for these phenomena can be given at present. Possible hypotheses involve differential leaching from the measurement vessel walls or a change in water molecule dynamics, i.e., in rotational correlation time and/or diffusion. Homeopathic preparations thus may exhibit specific physicochemical properties that need to be determined in detail in future investigations. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Hexavalent Chromium Sorption by Modified Cellulose Macro and Nanofibers Obtained from Eucalyptus Residues

Journal of Polymers and the Environment - Exposure to potentially toxic metallic elements (PTME) released in watercourses by industries results in irreversible damage to living beings or even...     

Spatial surrogates for the disaggregation of CORINAIR emission inventories

CORINAIR atmospheric emission inventories are frequently used input data for air quality models with a domain situated in Europe. In CORINAIR emission inventories, sources are broken down over 11 major source categories. This paper presents spatial surrogates for the disaggregation of CORINAIR atmospheric emission inventories for input of air pollutants and particulate matter to grid or polygon based air quality model domains inside Europe. The basis for the disaggregation model was the CLC2000 land cover data to which statistical weights were added. Weights were population census data for residential emissions, employment statistics for agricultural and industrial area emissions, livestock statistics for ammonia emissions and annual aircraft movements for emissions realized by air transport. Additional road and off-road network information was used to disaggregate emissions realized by traffic. A comparison of top down produced emission estimates with spatially resolved national emission data for The Netherlands and the United Kingdom gave confidence in the present spatial surrogates as a tool for the top down production of atmospheric emission maps. Explained variance at a spatial resolution of 5 km was >70% for CO, NMVOC and NO_x, >60% for PM10 and almost 50% for SO₂.     

Indicating ecosystem integrity — theoretical concepts and environmental requirements

This paper discusses some conceptual fundamentals for the derivation of environmental indicator sets. On the one hand, it defines requirements from environmental politics, environmental management and legislation, reaching from political target hierarchies and sustainable management strategies to holistic protection concepts such as process protection, resource preservation, ecosystem health and ecological integrity. On the other hand, demands from ecosystem theory are described which include the consideration of features such as self-organization, emergence, thermodynamics, gradients and ecological orientors in environmental indicator sets. From that concept, collective and emergent properties are selected and eight holistic ecosystem features are presented that indicate the ecosystemic state as an ensemble. These general indicators of ecosystem integrity are supplemented by variables on structural changes and substance dynamics.