scholarly journals Traceable PM2.5 and PM10 Calibration of Low-Cost Sensors with Ambient-like Aerosols Generated in the Laboratory

2021 ◽  
Vol 11 (19) ◽  
pp. 9014
Author(s):  
Stefan Horender ◽  
Georgi Tancev ◽  
Kevin Auderset ◽  
Konstantina Vasilatou
Keyword(s):  
Organic Matter ◽  
Low Cost ◽  
Gravimetric Method ◽  
Dust Particles ◽  
Sampling System ◽  
Gravimetric Measurements ◽  
Inorganic Species ◽  
Pm2.5 And Pm10 ◽  
First Time ◽  
Proof Of Principle

This work builds upon previous efforts at calibrating PM (particulate matter) monitors with ambient-like aerosols produced in the laboratory under well-controlled environmental conditions at the facility known as PALMA (Production of Ambient-like Model Aerosols). In this study, the sampling system of PALMA was equipped with commercial PM2.5 and PM10 impactors, designed according to the EN 12341:2014 standard, to select different aerosol size fractions for reference gravimetric measurements. Moreover, a metallic frame was mounted around the PM impactor to accommodate up to eight low-cost PM sensors. This sampling unit was placed at the bottom of the 2-meter-long aerosol homogenizer, right above the filter holder for the reference gravimetric measurements. As proof of principle, we used the upgraded PALMA facility to calibrate the new AirVisual Outdoor (IQAir, Goldach, Switzerland) and the SDS011 (InovaFitness, Jinan, China) low-cost PM sensors in a traceable manner against the reference gravimetric method according to the EN 12341 standard. This is the first time that PM2.5 and PM10 calibrations of low-cost sensors have been successfully carried out with complex ambient-like aerosols consisting of soot, inorganic species, secondary organic matter, and dust particles under controlled temperature and relative humidity.

scholarly journals Halley’s Comet (Part II): Space Studies

1989 ◽  
Vol 8 ◽  
pp. 17-31
Author(s):  
Vassili I. Moroz
Keyword(s):  
Organic Matter ◽  
Cometary Nucleus ◽  
Dust Particles ◽  
Spatially Resolved ◽  
Unique Event ◽  
Halley's Comet ◽  
Comet Dust ◽  
Comet Halley ◽  
First Time ◽  
Dark Body

AbstractAn international armada of spacecraft encountered Comet Halley in March 1986. The present article gives a brief overview of this unique event during which a cometary nucleus was seen as a spatially resolved object for the first time. It is a very dark body, the shape is irregular and the structure is inhomogeneous; only the sunward side is active. Many parent molecules were identified in the coma, including complicated hydrocarbons. There was also organic matter in the comet dust particles. Extensive studies were made of the complicated plasma environment of the comet.

scholarly journals The Impact of Ambient Atmospheric Mineral-Dust Particles on the Calcification of Lungs

Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 125
Author(s):  
Mariola Jabłońska ◽  
Janusz Janeczek ◽  
Beata Smieja-Król
Keyword(s):  
Mineral Dust ◽  
Smoking Habit ◽  
Lower Lobe ◽  
Ambient Air ◽  
Dust Particles ◽  
Masking Effect ◽  
Amorphous Calcium Carbonate ◽  
Calcium Salts ◽  
The Impact ◽  
First Time

For the first time, it is shown that inhaled ambient air-dust particles settled in the human lower respiratory tract induce lung calcification. Chemical and mineral compositions of pulmonary calcium precipitates in the lung right lower-lobe (RLL) tissues of 12 individuals who lived in the Upper Silesia conurbation in Poland and who had died from causes not related to a lung disorder were determined by transmission and scanning electron microscopy. Whereas calcium salts in lungs are usually reported as phosphates, calcium salts precipitated in the studied RLL tissue were almost exclusively carbonates, specifically Mg-calcite and calcite. These constituted 37% of the 1652 mineral particles examined. Mg-calcite predominated in the submicrometer size range, with a MgCO3 content up to 50 mol %. Magnesium plays a significant role in lung mineralization, a fact so far overlooked. The calcium phosphate (hydroxyapatite) content in the studied RLL tissue was negligible. The predominance of carbonates is explained by the increased CO2 fugacity in the RLL. Carbonates enveloped inhaled mineral-dust particles, including uranium-bearing oxides, quartz, aluminosilicates, and metal sulfides. Three possible pathways for the carbonates precipitation on the dust particles are postulated: (1) precipitation of amorphous calcium carbonate (ACC), followed by its transformation to calcite; (2) precipitation of Mg-ACC, followed by its transformation to Mg-calcite; (3) precipitation of Mg-free ACC, causing a localized relative enrichment in Mg ions and subsequent heterogeneous nucleation and crystal growth of Mg-calcite. The actual number of inhaled dust particles may be significantly greater than was observed because of the masking effect of the carbonate coatings. There is no simple correlation between smoking habit and lung calcification.

scholarly journals UV Inscription and Pressure Induced Long-Period Gratings through 3D Printed Amplitude Masks

Sensors ◽  
2021 ◽  
Vol 21 (6) ◽  
pp. 1977
Author(s):  
Ricardo Oliveira ◽  
Liliana M. Sousa ◽  
Ana M. Rocha ◽  
Rogério Nogueira ◽  
Lúcia Bilro
Keyword(s):  
State Of The Art ◽  
Low Cost ◽  
Resonance Wavelength ◽  
Complex Structures ◽  
Pressing Method ◽  
Long Period ◽  
Long Period Gratings ◽  
3D Printed ◽  
Mechanical Pressing ◽  
First Time

In this work, we demonstrate for the first time the capability to inscribe long-period gratings (LPGs) with UV radiation using simple and low cost amplitude masks fabricated with a consumer grade 3D printer. The spectrum obtained for a grating with 690 µm period and 38 mm length presented good quality, showing sharp resonances (i.e., 3 dB bandwidth < 3 nm), low out-of-band loss (~0.2 dB), and dip losses up to 18 dB. Furthermore, the capability to select the resonance wavelength has been demonstrated using different amplitude mask periods. The customization of the masks makes it possible to fabricate gratings with complex structures. Additionally, the simplicity in 3D printing an amplitude mask solves the problem of the lack of amplitude masks on the market and avoids the use of high resolution motorized stages, as is the case of the point-by-point technique. Finally, the 3D printed masks were also used to induce LPGs using the mechanical pressing method. Due to the better resolution of these masks compared to ones described on the state of the art, we were able to induce gratings with higher quality, such as low out-of-band loss (0.6 dB), reduced spectral ripples, and narrow bandwidths (~3 nm).

Printing ultrathin graphene oxide nanofiltration membranes for water purification

2017 ◽  
Vol 5 (39) ◽  
pp. 20860-20866 ◽  
Author(s):  
Mahdi Fathizadeh ◽  
Huynh Ngoc Tien ◽  
Konstantin Khivantsev ◽  
Jung-Tsai Chen ◽  
Miao Yu
Keyword(s):  
Graphene Oxide ◽  
Water Purification ◽  
Inkjet Printing ◽  
Low Cost ◽  
Nanofiltration Membranes ◽  
Highly Effective ◽  
First Time ◽  
Polymeric Supports ◽  
Effective Water

We demonstrated for the first time that inkjet printing can be a low-cost, easy, fast, and scalable method for depositing ultrathin (7.5–60 nm) uniform graphene oxide (GO) nanofiltration membranes on polymeric supports for highly effective water purification.

Antimony trifluoride incorporated SnO2 for high-efficiency planar perovskite solar cells

2021 ◽  
Author(s):  
Li Zhang ◽  
Hui Li ◽  
Jing Zhuang ◽  
Yigang Luan ◽  
Sixuan Wu ◽  
...  
Keyword(s):  
Solar Cells ◽  
Electron Transport ◽  
Tin Dioxide ◽  
High Efficiency ◽  
Low Cost ◽  
Perovskite Solar Cells ◽  
Transport Layer ◽  
Electron Transport Layer ◽  
Antimony Trifluoride ◽  
First Time

The low-cost material antimony trifluoride (SbF3) was doped into the commonly used tin dioxide (SnO2) for the first time, and the SbF3-doped SnO2 as an electron transport layer (ETL) was...

New Results of Using the Light Trap for Collecting Beetles (Insecta: Coleoptera) in the Urban Environment (on the Example of Saratov)

2020 ◽  
Vol 2 (2) ◽  
pp. 72-78
Author(s):  
A.S. Sazhnev ◽  
◽  
V.V. Anikin ◽  
Keyword(s):  
Invasive Species ◽  
Urban Areas ◽  
Harmonia Axyridis ◽  
Low Cost ◽  
Light Trap ◽  
Ecological Groups ◽  
Light Traps ◽  
Adventitious Species ◽  
First Time ◽  
Stegobium Paniceum

The article presents the results of research of the using light traps (luminescent lamp Actinic 6W) for collecting Coleoptera in the Saratov city. Entomological material was collected by the second author in the period from 1.06 to 2.10.2019. In 2019, 52 species of Coleoptera of 22 families from different ecological groups were recorded. A relatively high proportion of adventitious species remains in 17.3– 30.7% of the presented fauna was presented. For two years the 14 species of alien and cryptogenic Coleoptera species were observed, that is 24.5% of the adventive fauna of the Saratov Province. Among invasive species Attagenus smirnovi, Stegobium paniceum, Atomaria lewisi, Harmonia axyridis, Gnatocerus cornutus, and Orchestes steppensis were record for the first time in 2019. It to use bringing on light as one of the available and low-cost ways to identify alien and cryptogenic organisms in urban areas is recommended.

Impact of the Karnofsky Performance Status on Survival and its Dynamics during the Terminal Year of Peritoneal Dialysis Patients

2018 ◽  
Vol 38 (1) ◽  
pp. 24-29 ◽  
Author(s):  
Ana Paula Modesto ◽  
Len Usvyat ◽  
Viviane Calice-Silva ◽  
Dandara Novakowski Spigolon ◽  
Ana Elizabeth Figueiredo ◽  
...  
Keyword(s):  
Peritoneal Dialysis ◽  
Family Income ◽  
Independent Predictor ◽  
Karnofsky Performance Status ◽  
Low Cost ◽  
Performance Status ◽  
Multi Center Study ◽  
Complications And Mortality ◽  
First Time

Background Simple and low-cost tools to monitor the risk profile of patients on peritoneal dialysis (PD) at high risk of complications and mortality are scarce. One of the tools available to monitor the variation in vitality and dependence levels is the Karnofsky performance status (KPS). This study analyzed the average trends and variation of KPS during the 12 months before death and its independent value in predicting patients’ survival. Methods The data were compiled from the BRAZPD II multi-center study, performed in Brazil between 2004 and 2011. For the analysis of KPS dynamics, we included patients with at least 12 months of follow-up on PD and who had a fatal event during the follow-up. The following covariables were evaluated: age, gender, ethnicity, educational level, and presence of diabetes. We used the linear regression model to present the results: the log (time) before death was represented by the regression variable and KPS was the response. We also analyzed the independent impact of baseline KPS on patients’ survival. Results From the population of 9,905 patients enrolled in the BRAZPD study, 4,133 survived 12 months on PD and were included in the analysis. There was a gradual decline in the KPS scores, which accelerated in the last 2 months before death. These changes were similar irrespective of age, race, family income, gender, diabetes, PD modality, and education level. We observed 989 fatal events in this population during the observation period, and the KPS score was identified as an independent predictor for mortality in this cohort. Conclusions This study demonstrates for the first time the dynamics of KPS before death in PD patients, indicating a progressive and accelerated decline of KPS in the 12 months before patients died. In addition, KPS was an independent predictor of mortality in this population.

scholarly journals Species of Geotrupidae (Coleoptera: Scarabaeoidea) in Aquidauana, Mato Grosso do Sul, Brazil

2013 ◽  
Vol 13 (1) ◽  
pp. 349-352
Author(s):  
Sérgio Roberto Rodrigues ◽  
Anderson Puker
Keyword(s):  
Organic Matter ◽  
Light Trap ◽  
Abundant Species ◽  
Ecological Role ◽  
Mato Grosso ◽  
The Family ◽  
Total Capture ◽  
First Time ◽  
Mato Grosso Do Sul

Coleoptera of the family Geotrupidae play an important ecological role in the decomposition of animal and plant organic matter. In Brazil there is little information on the diversity and distribution of this group, thus, this work had a purpose to study Geotrupidae species, occurring in Aquidauana, MS. A survey for geotrupids was conducted in Aquidauana, Mato Grosso do Sul, Brazil. Beetles were captured using a light trap over a period of two years, from January 2006 to December 2007. A total of 907 specimens were collected and identified to eight species. From the subfamily Bolboceratinae, the species identified were Bolbapium minutum (Luederwaldt, 1929) and Pereirabolbus castaneus (Klug, 1845). In the subfamily Athyreinae the species identified were Athyreus bilobus Howden & Martínez, 1978, Parathyreus aff. bahiae, Neoathyreus aff. julietae, N. sexdentatus Laporte, 1840, N. centromaculatus (Felsche, 1909) and N. goyasensis (Boucomont, 1902). Four species (A. bilobus, N. centromaculatus, N. goyasensis and P. castaneus) are reported for the first time in Aquidauana, MS, Brazil. The most abundant species, representing 85.9% of the total capture, was B. minutum. The greatest numbers of specimens was caught from October to December of both years of the study.

scholarly journals Temperature and UV light affect the activity of marine cell-free enzymes

2017 ◽  
Vol 14 (17) ◽  
pp. 3971-3977 ◽  
Author(s):  
Blair Thomson ◽  
Christopher David Hepburn ◽  
Miles Lamare ◽  
Federico Baltar
Keyword(s):  
Organic Matter ◽  
Extracellular Enzymes ◽  
Elevated Temperatures ◽  
Uv Light ◽  
Control Mechanisms ◽  
Potential Control ◽  
Control Factors ◽  
Rate Limiting Step ◽  
Ocean Environment ◽  
First Time

Abstract. Microbial extracellular enzymatic activity (EEA) is the rate-limiting step in the degradation of organic matter in the oceans. These extracellular enzymes exist in two forms: cell-bound, which are attached to the microbial cell wall, and cell-free, which are completely free of the cell. Contrary to previous understanding, cell-free extracellular enzymes make up a substantial proportion of the total marine EEA. Little is known about these abundant cell-free enzymes, including what factors control their activity once they are away from their sites (cells). Experiments were run to assess how cell-free enzymes (excluding microbes) respond to ultraviolet radiation (UVR) and temperature manipulations, previously suggested as potential control factors for these enzymes. The experiments were done with New Zealand coastal waters and the enzymes studied were alkaline phosphatase (APase), β-glucosidase, (BGase), and leucine aminopeptidase (LAPase). Environmentally relevant UVR (i.e. in situ UVR levels measured at our site) reduced cell-free enzyme activities by up to 87 % when compared to controls, likely a consequence of photodegradation. This effect of UVR on cell-free enzymes differed depending on the UVR fraction. Ambient levels of UV radiation were shown to reduce the activity of cell-free enzymes for the first time. Elevated temperatures (15 °C) increased the activity of cell-free enzymes by up to 53 % when compared to controls (10 °C), likely by enhancing the catalytic activity of the enzymes. Our results suggest the importance of both UVR and temperature as control mechanisms for cell-free enzymes. Given the projected warming ocean environment and the variable UVR light regime, it is possible that there could be major changes in the cell-free EEA and in the enzymes contribution to organic matter remineralization in the future.

Point-of-entry adsorbers for the removal of fumigants

1995 ◽  
Vol 22 (1) ◽  
pp. 106-120
Author(s):  
Roberto M. Narbaitz ◽  
Frances Z. Parsons ◽  
Tsong-Yih Tzeng
Keyword(s):  
Organic Matter ◽  
Activated Carbon ◽  
Low Cost ◽  
Scale Up ◽  
Extensive Literature ◽  
Limited Data ◽  
Ethylene Dibromide ◽  
Point Of Entry ◽  
Naturally Occurring ◽  
Adsorption Data

Point-of-entry systems with granular activated carbon filters have been used extensively to provide safe water to rural homes with wells contaminated with synthetic organic chemicals. Because of the low cost of these systems, their design is generally based on the equilibrium column model, the isotherm data from the literature, and a scale-up factor. This paper analyzes the necessary scale-up factors for point-of-entry adsorbers based on fumigant adsorption data gathered through an extensive literature review. The fumigants evaluated are 1,2-dichloropropane, 1,2-dibromo-3-chloropropane, and ethylene dibromide. It was impossible to thoroughly assess the scale-up factors for 1,2-dichloropropane because of the limited data. Column data for the other two fumigants were sufficient to generate column loading lines, which can be used directly without resorting to scale-up factors. Column data showed that the scale-up factors are greatly affected by competitive adsorption with the naturally occurring background organic matter and by preloading of these organic matter. As these phenomena are not well understood, it is presently impossible to accurately predict the appropriate scale-up factors. A recommended design approach is outlined. Key words: adsorption, activated carbon, fumigants, point-of-entry.

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