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A study aimed at developing a multiresidue (MR) method to determine the pesticide residues in drinking water, groundwater, and surface water is presented. The experiment utilized solid-phase (SPE) extraction through graphitized carbon black (Carbograph 4) followed by liquid chromatography electrospray mass spectrometry (LC/ES/MS) in analyzing 45 commonly used pesticides. The results of the experiments indicate that the combination of a Carbograph 4 SPE cartridge with LC/ES/MS can ideally be used for fast, clear, and accurate determination of pesticide traces in aqueous matrices.

Three cases are reviewed of radioactive material with anomalous decay after ultrasound irradiation. In the pure element thorium-228 in distilled water, the radioactivity decreased faster after cavitation than the natural decay. The more complex molecule of Nickel Nitrate, made of radioactive nickel-63, in solution of nitric acid and distilled water was investigated before and after ultrasound irradiation. The X-rays produced by Bremsstrahlung of the electrons from the beta decay of Ni-63 were recorded and a 13% decrease of intensity was measured after 100 s of sonication. A decrease of nickel and an increase of other elements was detected by mass spectrometry in the sonicated sample. The Cobalt-57 decay was investigated by detecting the gamma and X-ray intensity from the Iron-57 resulting after its beta emission. In this third case too, an anomalous decay was observed after sonication. These three cases of anomalous behavior can be explained at the light of the Deformed Space–Time theory. It assumes that a suitable sudden variation of energy density can induce a local deformation of space–time, thus violating the Local Lorentz Invariance. This variation can be created by the ultrasounds in the matter, thus, allowing reactions that cannot occur in a flat (Minkowskian) space–time. The "neutralization" of a radionuclide occurs when it undergoes a DST transformation changing the radionuclide into non-radioactive nuclides. [ABSTRACT FROM AUTHOR]

CO2adsorption on synthetic zeolites has become a consolidated approach for biogas upgrading to biomethane. As an alternative to synthetic zeolites, tuff waste from building industry was investigated in this study: indeed, this material is available at a low price and contains a high fraction of natural zeolites. A selective adsorption of CO2and H2S towards CH4was confirmed, allowing to obtain a high-purity biomethane (CO2<2 g m−3, i.e. 0.1%; H2S <1.5 mg m−3), suitable for injection in national grids or as vehicle fuel. The loading capacity was found to be 45 g kg−1and 40 mg kg−1, for CO2and H2S, respectively. Synthetic gas mixtures and real biogas samples were used, and no significant effects due to biogas impurities (e.g. humidity, dust, moisture, etc.) were observed. Thermal and vacuum regenerations were also optimized and confirmed to be possible, without significant variations in efficiency. Hence, natural zeolites from tuffs may successfully be used in a pressure/vacuum swing adsorption process. [ABSTRACT FROM AUTHOR]

Cement plants are responsible for particle and gaseous emissions into the atmosphere. With respect to particle emission, the greater part of is in the range from 0.05 to 5.0 µm in diameter. In the last years attention was paid to submicron particles, but there is a lack of available data on the emission from stationary sources. In this paper, concentration and size distribution of particles emitted from four cement kilns, in relationship to operational conditions (especially the use of alternative fuel to coal) of the clinker process are reported. Experimental campaigns were carried out by measuring particles concentration and size distribution at the stack of four cement plants through condensation particle counter (CPC) and scanning mobility particle sizer spectrometer (SMPS). Average total particle number concentrations were between 2000 and 4000 particles/cm3, about 8–10 times lower that those found in the corresponding surrounding areas. As for size distribution, for all the investigated plants it is stable with a unimodal distribution (120–150 nm), independent from the fuel used. Implications: The study provides information on submicron particles emitted from cement kilns in different driving conditions. In particular, the total particle number is modest and considerably lower than that measured in ambient air, whereas the particle size distribution could be influenced by the operational conditions. [ABSTRACT FROM AUTHOR]

Residential air cleaners exploiting different technologies re commonly used today to remove air contaminants from indoor environments. Different methods have been developed in the USA and Europe to test their efficiency. The one used in the USA provides a more comprehensive view of indoor processes, because testing is performed in a large simulation chamber (28.5 m3), using anthropogenic emissions, such as cigarette smoke, to generate pollution. Testing rooms are also important to investigate new removal technologies, or to improve them. Since no such testing facilities exist in Italy, one of 12.4 m3 was built in which cigarette smoke, resuspended dust from agricultural soil and, for the first time, diesel exhaust emissions were used to generate indoor pollution. Performances were tested with two air cleaning systems, exploiting completely different removal technologies. Accurate values of decay rates of indoor pollutants were obtained using a suite of on-line and out-of-line monitors for the measurement of particulate matter, volatile organic compounds (VOCs) and some inorganic gases. Proton-transfer mass spectrometry (PTR-MS) provided an almost real-time detection of several VOCs and H2S, at trace levels (0.01 ppbv). A method using a common in vitro bioassay was developed to assess the ability of air cleaners to remove indoor toxic substances. [ABSTRACT FROM AUTHOR]

In automobile repair shops (or garage) activity, it is necessary to undertake a detailed assessment of the health risks (e.g., chemicals for work procedures). The worker may be exposed to welding fumes during assembly procedures (welding operation), and to sanding dust and solvents (e.g., toluene, xylenes, isocyanates, styrene and pigments) contained in grouts. The exposure degree depends on the mode of use, the amount used, the rate of use and personal protective equipment. The staff responsible performs interventions ranging from simple maintenance to repairs. For chemical agent measurements, it is necessary to use standardized methods or appropriate methods; regarding the ultrafine particles, it should be better to obtain information as possible in terms of number and trend. In this paper the working procedures such as machines sanding and painting are deeply investigated. These processes result in high chemical risk (Volatile Organic Compounds, VOCs) and production of ultrafine particles that can be harmful to exposed workers. No significant critical situations have been evidenced either as weighted averages in turn as both short term exposure, despite the fact that during operations some solvents (e.g., 1,2-dichloropropane) reach levels close to the STEL limit. For the airborne particulate matter (PM10, PM2.5, PM1 and respirable fraction) values lower than the limit values are observed. Further, the behavior of each fraction is shown and commented. Even if the indoor air quality in different garages investigated is not critical with regards to ultrafine particles and VOCs, the situation described above shows that the chemical risk in the garage sector cannot be considered negligible. In addition, it highlights the need to continuously monitor the particle component in relation to the worker exposure. [ABSTRACT FROM AUTHOR]

A short field campaign was performed in the outskirts of Rome at four sites located pretty along the four rose wind directions to city centre. Both chlorinated (PCB and PCDD/F) and non-chlorinated (n-alkanes, PAH, nitrated-PAH, n-alkanoic acids) organic micropollutants were investigated for their contents in the atmosphere. Concentrations reached by these pollutants in the outskirts were compared to those found in downtown Rome, both inside and outside of its largest city garden. Although concentrations of organic pollutants found in the outskirts were quite low, however they seemed enough high to induce some health risk in humans. Rural sites were less affected than industrial and waste disposal/treatment areas.