scholarly journals PAHs levels in gas and particle-bound phase in schools at different locations in Serbia

2015 ◽  
Vol 21 (1-2) ◽  
pp. 159-167 ◽  
Author(s):  
Marija Zivkovic ◽  
Milena Jovasevic-Stojanovic ◽  
Anka Cvetkovic ◽  
Ivan Lazovic ◽  
Visa Tasic ◽  
...  

This study investigated seasonal variation of PAHs and their partition between gas and particulate-bounded phases in indoor and outdoor air in 4 schools in Serbia located at different locations. The sampling campaigns were conducted during one workweek at each school successively. Campaigns were conducted in schools during heating and non-heating seasons in December 2011 and June 2012. Seasonal variations of gas and particle-bounded PAHs concentrations were observed with higher levels during heating season. The highest total PAH values were associated with the gas phase in both sampling periods. The total PAHs concentration at indoor and at the outdoor sites, during heating season, ranged from 88.45 to 447.72 ng/m3 and 201.69 to 1017.15 ng/m3, respectively. During non-heating season, the total PAHs concentration ranged from 36.91 to 271.57 ng/m3 in indoor environment and 27.00 to 132.32 ng/m3 in outdoor environment. Most of the I/O ratios were less than 1, which indicated that the indoor PAHs were mostly from outdoor sources. The use of diagnostic ratio showed that traffic emission and coal combustion are the major sources of PAHs. Only the diagnostic ratios for the school, located near the industrial area, showed significant deviation compared to other schools.

2012 ◽  
Vol 476-478 ◽  
pp. 1714-1717 ◽  
Author(s):  
Liang Bin Tan

Raw soil is a kind of good ecological building material. But in fact abundant adobe houses in Western China have many defects such as bad indoor environment. This paper discusses from the point of view the ecological characteristics and thinks of that these defects are not the fault of soil itself but the limitation of its constructor’s knowledge. So the author analyses the indoor and outdoor environment of adobe houses and proposes new points that raw soil is a sustainable material which could be absolutely used in rural houses of Western China and at the same time its economic effectiveness is incomparable to other building materials.


2021 ◽  
Vol 17 (2) ◽  
pp. 165-173
Author(s):  
Yunita Tri Utami ◽  
Susanti Pudji Hastuti ◽  
Bowo Nurcahyo

This research aims to determine the time limit needed and the environmental conditions that provide the highest success rate in identifying dried blood samples on the fabric of stretch denim, ramie denim, black coated denim, and dry denim jeans using the elution absorption method. Also, to evaluate the effect of the fabric fabric, environmental condition, time, and interactions regarding the success rate of blood group identification. The study was conducted using 3 replications for each type of jeans fabric, which was carried out by exposing blood to a jeans fabric, leaving it in an indoor and outdoor environment for up to 336 hours (14 days), then continued by making a red blood cell suspension for comparison, and examining blood groups using the absorption-elution method. From the results obtained, it is known that the blood exposed in the jeans fabric that being placed indoor for up to 336 hours (14 days) can still be identified and has a success percentage rate of up to 100%. Meanwhile, the blood exposed on the jeans fabric that was placed outdoor could no longer be identified after 264 hours (11 days). Based on the result of this study, it can be concluded that the exposure time of 366 hours (14 days) for the indoor environment can still be identified properly, while the exposure time of 264 hours (11 days) for dry blood samples in the outdoor environment can no longer be identified. The indoor environment gives a better percentage of success than the outdoor environment in identifying blood types from dry blood samples. The best types of substrates that can store blood at an exposure time of up to 336 hours (14 days) are dry denim, black coated denim, and stretch denim.


2021 ◽  
Vol 14 (4) ◽  
pp. 1520-1525
Author(s):  
Prachi Dixit

Comparative analysis of airborne bacterial load in the rural and urban indoor and outdoor environment is of utmost importance to evaluate the wellbeing hazards linked with co3ntamination of airborne bacteria in the indoor environment. The present study was conducted during December, 2020 to March, 2021 among 50 randomly selected rural and urban (Adupurajagir and Gwalior, respectively) dwellings to determine the indoor and outdoor bacterial load. The mean load of 562.35 CFU/m3 airborne bacteria was recorded in the indoor environment of a modular kitchen in Gwalior city. The mean load of 2593.75 CFU/m3 bacteria was recorded in the indoor environment of the traditional kitchen in Adupurajagir village. In addition, bacterial load of respectively 1215.13 CFU/m3 and 783.03 CFU/m3 was calculated in the open space at both study sites. Based on morphological characteristics five bacterial species (spp.) were identified Staphylococcus aureus spp, Bacillus spp, Coagulase-negative Staphylococcus spp, E-coli spp, and Micrococcus spp. By gram staining method the most common bacteria were gram-positive (+ve) [n=85, 54.48% (37.17% cocci, 17.94% bacilli)] followed by gram-negative (-ve) [n=71, 45.51% (23.07% cocci, 21.79% bacilli)] identified. Pearson’s correlation coefficient was employed between bacterial load and physical factors of the indoor environment in the rural traditional kitchen. Bacterial load (CFU/m3) showed a significant correlation with temperature (p < 0.001). However, a non-significant correlation was recorded with relative humidity (p > 0.01). High bacterial load was found in the rural traditional kitchen’s indoor environment compared to urban modular kitchen. Outcomes from this study revealed that bioaerosol sampling could deliver fruitful knowledge about the variation of air quality and prevent possible hospital admissions.


2018 ◽  
Vol 24 (9) ◽  
pp. 78 ◽  
Author(s):  
Jasim Ahmed Ali AL-Baghdadi ◽  
Hassan Ali Alizze ◽  
Kasim Abed AL-Hussein

Due to the great evolution in digital commercial cameras, several studies have addressed the using of such cameras in different civil and close-range applications such as 3D models generation. However, previous studies have not discussed a precise relationship between a camera resolution and the accuracy of the models generated based on images of this camera. Therefore the current study aims to evaluate the accuracy of the derived 3D buildings models captured by different resolution cameras. The digital photogrammetric methods were devoted to derive 3D models using the data of various resolution cameras and analyze their accuracies. This investigation involves selecting three different resolution cameras (low, medium and high) and evaluating their calibration accuracies. Assessing the accuracy of the three selected cameras in capturing indoor and outdoor objects; and analyzing the accuracy and the quality of the produced models. The study revealed that:1) It is recommended to use the photos of a high-resolution camera for producing precise 3D models of objects in the outdoor environment especially when the camera/object distance is more than 40 m because the accuracy of the  produced models can be  precise (RMSE ±10.36mm) with excellent quality; 2) The Low-resolution camera can be utilised to produce adequate 3D models of object in the indoor environment (RMSE ±6.32mm) especially when the camera/object distance is less than 40 m.  


Sensors ◽  
2021 ◽  
Vol 21 (12) ◽  
pp. 3955
Author(s):  
Jung-Cheng Yang ◽  
Chun-Jung Lin ◽  
Bing-Yuan You ◽  
Yin-Long Yan ◽  
Teng-Hu Cheng

Most UAVs rely on GPS for localization in an outdoor environment. However, in GPS-denied environment, other sources of localization are required for UAVs to conduct feedback control and navigation. LiDAR has been used for indoor localization, but the sampling rate is usually too low for feedback control of UAVs. To compensate this drawback, IMU sensors are usually fused to generate high-frequency odometry, with only few extra computation resources. To achieve this goal, a real-time LiDAR inertial odometer system (RTLIO) is developed in this work to generate high-precision and high-frequency odometry for the feedback control of UAVs in an indoor environment, and this is achieved by solving cost functions that consist of the LiDAR and IMU residuals. Compared to the traditional LIO approach, the initialization process of the developed RTLIO can be achieved, even when the device is stationary. To further reduce the accumulated pose errors, loop closure and pose-graph optimization are also developed in RTLIO. To demonstrate the efficacy of the developed RTLIO, experiments with long-range trajectory are conducted, and the results indicate that the RTLIO can outperform LIO with a smaller drift. Experiments with odometry benchmark dataset (i.e., KITTI) are also conducted to compare the performance with other methods, and the results show that the RTLIO can outperform ALOAM and LOAM in terms of exhibiting a smaller time delay and greater position accuracy.


Atmosphere ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 667
Author(s):  
Qingyuan Guo ◽  
Liming Li ◽  
Xueyan Zhao ◽  
Baohui Yin ◽  
Yingying Liu ◽  
...  

To better understand the source and health risk of metal elements in PM2.5, a field study was conducted from May to December 2018 in the central region of the Liaoning province, China, including the cities of Shenyang, Anshan, Fushun, Benxi, Yingkou, Liaoyang, and Tieling. 24 metal elements (Na, K, V, Cr, Mn, Co, Ni, Cu, Zn, As, Mo, Cd, Sn, Sb, Pb, Bi, Al, Sr, Mg, Ti, Ca, Fe, Ba, and Si) in PM2.5 were measured by ICP-MS and ICP-OES. They presented obvious seasonal variations, with the highest levels in winter and lowest in summer for all seven cities. The sum of 24 elements were ranged from to in these cities. The element mass concentration ratio was the highest in Yingkou in the spring (26.15%), and the lowest in Tieling in winter (3.63%). The highest values of elements in PM2.5 were mostly found in Anshan and Fushun among the studied cities. Positive matrix factorization (PMF) modelling revealed that coal combustion, industry, traffic emission, soil dust, biomass burning, and road dust were the main sources of measured elements in all cities except for Yingkou. In Yingkou, the primary sources were identified as coal combustion, metal smelting, traffic emission, soil dust, and sea salt. Health risk assessment suggested that Mn had non-carcinogenic risks for both adults and children. As for Cr, As, and Cd, there was carcinogenic risks for adults and children in most cities. This study provides a clearer understanding of the regional pollution status of industrial urban agglomeration.


Atmosphere ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 768
Author(s):  
Natalia Zioła ◽  
Kamila Banasik ◽  
Mariola Jabłońska ◽  
Janusz Janeczek ◽  
Barbara Błaszczak ◽  
...  

Raman microspectroscopy and thermo-optical-transmittance (TOT) method were used to study airborne ambient soot collected at the suburban air monitoring station in southern Poland during the residential heating (January-February) and non-heating (June–July) seasons of 2017. Carbonaceous material constituted on average 47.2 wt.% of PM2.5 during the heating season and 26.9 wt.% in the non-heating season. Average concentrations of OC (37.5 ± 11.0 μg/m3) and EC (5.3 ± 1.1 μg/m3) during the heating season were significantly higher than those in the non-heating season (OC = 2.65 ± 0.78 μg/m3, and EC = 0.39 ± 0.18 μg/m3). OC was a chief contributor to the TC mass concentration regardless of the season. All Raman parameters indicated coal combustion and biomass burning were the predominant sources of soot in the heating season. Diesel soot, which is structurally less ordered than soot from other sources, was dominant during the non-heating season. The D1 and G bands area ratio (D1A/GA) was the most sensitive Raman parameter that discriminated between various soot sources, with D1A/GA > 1 for diesel soot, and less than 1 for soot from coal and wood burning. Due to high daily variability of both TOT and Raman spectroscopy data, single-day measurements can be inconclusive regarding the soot source apportionment. Long-time measurement campaigns are recommended.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jun-ichi Kanatani ◽  
Masanori Watahiki ◽  
Keiko Kimata ◽  
Tomoko Kato ◽  
Kaoru Uchida ◽  
...  

Abstract Background Legionellosis is caused by the inhalation of aerosolized water contaminated with Legionella bacteria. In this study, we investigated the prevalence of Legionella species in aerosols collected from outdoor sites near asphalt roads, bathrooms in public bath facilities, and other indoor sites, such as buildings and private homes, using amoebic co-culture, quantitative PCR, and 16S rRNA gene amplicon sequencing. Results Legionella species were not detected by amoebic co-culture. However, Legionella DNA was detected in 114/151 (75.5%) air samples collected near roads (geometric mean ± standard deviation: 1.80 ± 0.52 log10 copies/m3), which was comparable to the numbers collected from bathrooms [15/21 (71.4%), 1.82 ± 0.50] but higher than those collected from other indoor sites [11/30 (36.7%), 0.88 ± 0.56] (P < 0.05). The amount of Legionella DNA was correlated with the monthly total precipitation (r = 0.56, P < 0.01). It was also directly and inversely correlated with the daily total precipitation for seven days (r = 0.21, P = 0.01) and one day (r = − 0.29, P < 0.01) before the sampling day, respectively. 16S rRNA gene amplicon sequencing revealed that Legionella species were detected in 9/30 samples collected near roads (mean proportion of reads, 0.11%). At the species level, L. pneumophila was detected in 2/30 samples collected near roads (the proportion of reads, 0.09 and 0.11% of the total reads number in each positive sample). The three most abundant bacterial genera in the samples collected near roads were Sphingomonas, Streptococcus, and Methylobacterium (mean proportion of reads; 21.1%, 14.6%, and 1.6%, respectively). In addition, the bacterial diversity in outdoor environment was comparable to that in indoor environment which contains aerosol-generating features and higher than that in indoor environment without the features. Conclusions DNA from Legionella species was widely present in aerosols collected from outdoor sites near asphalt roads, especially during the rainy season. Our findings suggest that there may be a risk of exposure to Legionella species not only in bathrooms but also in the areas surrounding asphalt roads. Therefore, the possibility of contracting legionellosis in daily life should be considered.


2012 ◽  
Vol 245 ◽  
pp. 255-260 ◽  
Author(s):  
Rudolf Jánoš ◽  
Mikuláš Hajduk ◽  
Ján Semjon ◽  
Ľuboslava Šidlovská

Wheels and legs are two widely accepted methodology used to move the moving platform to the ground. Wheels are human inventions, the rolls in a straight country excel in energy efficiency and speed of movement. Hybrid platform for integrating the benefits of legs and wheels with high mobility of both seems to be the "future" of mobile platforms for indoor and outdoor environment. This paper describes the design leg-wheel chassis for service robot.


2014 ◽  
Vol 881-883 ◽  
pp. 1233-1236
Author(s):  
Zhong Hua Wang

In this paper, ways of heat transfer through windows and doors between the indoor and outdoor environment in the northern area are summarized. And every heat transfer way is described by mathematical formula. On this basis, methods to improve the energy saving performance of exterior windows are put forward according to factors affecting heat transfer through windows. The first method is increasing solar radiation heat, and then reducing heat loss by infiltration, and increasing the thermal resistance as much as possible. Ideal form of energy-saving window is proposed based on compared windows with different material and thermal resistance.


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