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Abstract

The aim of this article is to examine the effect of temperature, humidity, air velocity and CO2 concentration regarding the human behaviour in indoor environment with natural ventilation, i.e. without a ventilation device, or where there is forced ventilation or an air conditioning.

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Abstract

This paper presents the results of the floristical examinations performed in the units of a former secondary sedimentation pond system in Hungary. The outcome of analyses on the chromium content of the plants is discussed. Beside the chemical analyses, observations on the plants, the characterization of the ecological state of plant stands adapted to heavy metal load. Results of the elemental analysis for heavy metals revealed that none of the plants constituting the natural vegetation can be treated as hyperaccumulator plant. A green cover and the detoxification process of Cr(VI) by plants is suggested to be more important than the present extensive phytoextraction procedure. It can be stated that due to the disturbance our investigated area has diverse vegetation, in addition these plants can tolerate a high concentration of heavy metals, and they are able to take up them.

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It is a prime aim to ensure a suitable comfort level in case of office buildings. The productivity of office employees is directly influenced by the comfort. Thermal discomfort and poor indoor air quality deteriorate the intensity and quality of human work. We investigated the comfort in office buildings with on-site measurements during the summer season. The office buildings were operating with different HVAC (Heating, Ventilating and Air-Conditioning) systems: ducted fan-coil with suspended ceiling, installation, non-ducted fan-coil with floor-mounted installation, active chilled beam with fresh air supply.

We evaluated the thermal comfort under PMV (Predicted Mean Vote), PPD (Predicted Percentage of Dissatisfied), the local discomfort based on DR (Draught Rate) and the IAQ (Indoor Air Quality) based on carbon dioxide concentration. The comfort measurements were evaluated. The measurements were evaluated with scientific research methods, comfort categories based on the requirements of CR 1752. The results of this comparison were presented in this article.

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A szennyvíz alapú epidemiológia jelentősége a COVID–19 járványban és azon túl

The importance of wastewater-based epidemiology in the COVID-19 pandemic and beyond

Scientia et Securitas
Authors: Tamás Pándics, Eszter Róka, Bernadett Khayer, Zoltán Kis, Luca Bella Kovács, Nóra Magyar, Tibor Málnási, Orsolya Oravecz, Bernadett Pályi, Eszter Schuler, and Márta Vargha

Összefoglaló. A szennyvízalapú epidemiológia módszere a jelenlegi világjárványban egyre inkább előtérbe kerül. Mivel a szennyvízhálózatot szinte mindenki használja, ezzel a módszerrel gyorsan és olcsón lehet reprezentatív egészségügyi információhoz jutni, az így keletkező adatok pedig támogatást és visszajelzést nyújthatnak a döntéshozatalban. A Nemzeti Népegészségügyi Központ 2020 júniusa óta működteti a COVID–19 előrejelző rendszert. A mintavételek hetente történnek Budapest három szennyvíztisztítójából, valamint a megyeszékhelyekről. A kapott adatok hazánkban is előrejelzik az esetszám alakulását, az eredmények gyors kommunikációja pedig lehetővé teszi a járványhelyzetre történő felkészülést. A szennyvízalapú epidemiológia alkalmazása a jövőben más területeken is megfontolandó hazánkban is.

Summary. Wastewater based epidemiology (WBE) is an emerging method in the current COVID-19 pandemic. Since almost everyone uses the sewerage system, wastewater is technically a composite sample representing the entire population of the area serviced by a wastewater plant. This community sample contains pathogens and compounds excreted by the human body through feces or urine, and can be used to obtain information on the health status of the community. It was successfully used previously for confirming the eradication of poliovirus and tracking legal and illegal drug consumption.

The etiological agent of COVID-19, the SARS-CoV-2 virus is an enveloped, single strand RNA coronavirus. Although it is a respiratory virus, it is also shed in feces both in symptomatic and asymptomatic infections. Wastewater therefore can be used to estimate outbreak trends and support outbreak management.

Wastewater monitoring efforts in Hungary started in June 2020, first in Budapest, then gradually extended to a national surveillance system. Weekly samples are collected in the three wastewater treatment plants servicing Budapest, and from every county seat. The analyzed 22 samples represent approximately 40 % of the population. Raw sewage samples are centrifuged to remove the debris and concentrated by membrane ultrafiltration. RNA is extracted from the concentrate and SARS-CoV-2 is quantified by RT-qPCR. Results are normalized to Enterococcus counts to correct for the bias of dilution from precipitation.

The first results in June reflected the decline of the first wave of the outbreak. During the summer, viral RNA concentrations were low, mainly below the limit of detection. The increase of RNA in the sewage preceded the resurge of cases by 2 weeks. Trends of viral concentration followed the same pattern as the number of infections in the second and third wave. SARS-CoV in sewage shows statistically significant association with the number of new cases in the following weeks, thus it can be used as an early warning system.

Results are communicated weekly to the governance board responsible for outbreak management, or more frequently in case of outstanding results or when it is necessary for decision support. Weekly information is also made available to the public. To inform the public, concentration categories (low, medium, elevated and high) were defined, representing orders of magnitude of the viral RNA concentration. Trends (increasing, stagnating or decreasing) are also indicated.

The establishment of a long-term wastewater surveillance system would provide an opportunity for early recognition of future emerging infections, tracking seasonal influenza, drug use or even the detection of certain bioterror attacks. It would be an important addition to maintaining the health and safety of the Hungarian population.

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Nanoparticle Concentration Eff. results max/increase % Comments [ 17 ] Water Al 2 O 3 0.2, 0.25, 0.3%wt 13% Al 2 O 3 , 11% Fe 2 O 3 Variable flow rate [ 18 ] Water Al 2 O 3 3, 1%vol 52.4, 73 Variable incident angles [ 19 ] Water TiO 2 0.05, 0.1, 0.2, 0.5%vol 56

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Resolution and Discovery
Authors: Svetlana Jovanovic, Olaf C. Haenssler, Milica Budimir, Duška Kleut, Jovana Prekodravac, and Biljana Todorovic Markovic

into water (200 mL) and filtrated until the pH was 7. Chemical reduction of both GO and GQDs was conducted using in situ generated hydrogen [ 7 ]. Synthesized GQD and GO were dispersed in water in a concentration of 1 mg/mL and the ccHCl acid (35

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protection of the public against indoor exposure to radon (90/143/Euratom) Nagy É. H., Breitner D., Horváth Á., Szabó Cs. Study of a passive radon mitigation process and indoor radon concentration’s time dependence after

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2008 Continuous monitoring of residual chlorine concentrations in response to controlled microbial intrusions in a laboratory-scale distribution system Water Research 42 3162

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bacterial cells were re-suspended in phosphate-buffered saline solution (PBS) and adjusted to the required concentration. Antibacterial activity experiments To assess the ability of K/rGO-CS matrix to capture and kill bacteria, each substrate was immersed in

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). The measurement conditions were an accelerating voltage of 30 kV with a beam diameter of 1 μm for a counting time of 60–120 s and a minimum detectable weight concentration ranging from 0.1 to 1 wt%. Physical separation treatment for Abu Rusheid

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