Determination of hygroscopic aerosol growth based on the OPC-N3 counter

2021 ◽  
Author(s):  
Katarzyna Nurowska ◽  
Grzegorz Florczyk ◽  
Agata Han ◽  
Michał Chiliński ◽  
Krzysztof Markowicz
Keyword(s):  
Growth Factor ◽  
Relative Humidity ◽  
Low Cost ◽  
City Center ◽  
Hygroscopic Properties ◽  
Particle Matter ◽  
First Results ◽  
The University ◽  
The City

<p>In this study the OPC-N3 low-cost particle matter counter was used to determine the hygroscopic properties of the aerosol. The work shows the first results of aerosol hygroscopicity conducted in Poland. The study was performed during Spring 2020 (lock-down period) and Winter 2020/2021. The research was conducted in the Geophysics Institute at the University of Warsaw, close to the city center. </p><p>Two OPC-N3 sensors were connected to the outlet from two legs of the Aerosol Conditioning System ACS1000. In one of them, low relative humidity was kept at the level of 20%, and in the other, the relative humidity was changed in the range of 50-90% in cycles.</p><p>The calculation of growth factor was done by dividing the PM1 measured from wet pipe by PM1 measured in the dry channel. The hygroscopicity parameter κ was calculated from κ-Köhler theory, showing a fluctuation of the κ parameter which depends on aerosol type.</p><p>The variability of κ during Spring was ranging from values of 0.075 up to 0.437 (growth factor range 1.294 – 2.625).  The observed κ for Winter oscillates between 0.018 - 0.077 (growth factor range 1.057 – 1.246). The values of hygroscopicity of aerosol in winter are smaller than the ones corresponding to Spring, in line with respect to previous literature reports.</p><p>The study shows possibility to use OPC-N3 for calculation of the hygroscopic properties of the aerosol, however it means that the measurements of PM done by OPC-N3 can be biased by high relative humidity.</p>

MAX-DOAS measurements of NO2 and HCHO in the city of Kinshasa from 2019-2020

2021 ◽  
Author(s):  
Rodriguez Yombo ◽  
Alexis Merlaud ◽  
Gaia Pinardi ◽  
Emmanuel Mahieu ◽  
Martina Friedrich ◽  
...  
Keyword(s):  
Low Cost ◽  
Optical Absorption Spectroscopy ◽  
Small Computer ◽  
Vertical Column ◽  
First Results ◽  
Spectroscopy System ◽  
June July ◽  
The University ◽  
The City

<p>Recent studies in Kinshasa show how much air pollution is present in this large megalopolis of 13 million inhabitants, with levels even exceeding the recommended values (WHO, 2018).</p><p>From May 2017 to November 2019, the University of Kinshasa (UniKin: -4.42°S, 15.31°E) has equipped itself with a low-cost instrument operating in single-axis mode. Studies based on measurements made with this instrument have demonstrated the presence of NO2 with highest vertical column densities (VCDs) in June, July and August (R. Yombo, 2020). With this low-cost instrument, information such as aerosol and NO2 profile, which have major impacts on the determination of VCDs could not be obtained, leading to considerable uncertainties in the results obtained.</p><p>This work therefore supports the first one as described above, by presenting first results of a new MAX-DOAS (multi-axis differential optical absorption spectroscopy) system built at the IASB, in Belgium, and installed in Kinshsasa at the same location in November 2019. We first present the new MAX-DOAS, which is based on compact Avantes spectrometer (280-550 nm, 0.7 nm FWHM), a small computer, and a scanner.  We describe the analyses for aerosol extinction, HCHO and NO2 using FRM4-DOAS. For these two molecules, we compare with model simulations (GEOS-Chem) and satellite observations (OMI, TROPOMI).</p>

Strengthening of a City Center Tunnel with Concrete Screw Anchors under Special Boundary Conditions

2019 ◽  
Author(s):  
Johannes Lechner ◽  
Jürgen Feix ◽  
Robert Hertle
Keyword(s):  
Ductile Failure ◽  
High Strength ◽  
Shear Capacity ◽  
City Center ◽  
Cracked Concrete ◽  
Concrete Girders ◽  
Effective Depth ◽  
The University ◽  
The City ◽  
East West

<p>The Altstadtring-Tunnel is one of the essential east-west traffic routes in the city center of Munich and was constructed in the late 1960s. Segment 34 of the tunnel was built directly underneath the existing Prince-Carl- Palais, a historic building from 1804. Therefore 15 pre-stressed concrete girders with an effective depth of</p><p>3.5 m and a maximum span of up to 30 m were built which now form the tunnel roof slab. These girders were pre-stressed with steel nowadays well known for stress corrosion cracking. A recalculation of the slab showed that no ductile failure can be guaranteed in case of a progressive rupture of the tendons. Therefore, a concept for strengthening the slab was developed using concrete screw anchors as post installed bending and shear reinforcement. The concrete screw anchors are normally installed as anchoring elements in cracked and non- cracked concrete and are available with diameters up to 22 mm. Developing this concept further, it is straight forward to use these anchoring elements as post-installed reinforcement in existing concrete structures. This new strengthening system was developed at the University of Innsbruck in the last few years and can fulfill the special requirements of this project, such as installation of the strengthening system from underneath the tunnel slab during ongoing use of the structure. High strength steel with diameters of up to 63.5 mm will be used as post-installed bending reinforcement covered with a new shotcrete layer on the underside of the tunnel slab. In total 59.3 tons of new flexural reinforcement and 7199 concrete screws for strengthening the shear capacity of the girders will be used to ensure a ductile failure of the tunnel slab. The on-site work started in March 2019 and is expected to take two years to complete.</p>

scholarly journals UKRAINIANS IN St. PETERSBURG IN SCIENTIFIC AND PUBLIC ACTIVITY OF TETIANA LEBEDYNSKA

2021 ◽  
pp. 114-120
Author(s):  
Tetiana Тsymbal
Keyword(s):  
Life Events ◽  
Western Europe ◽  
The United States ◽  
Arab Countries ◽  
Town Planning ◽  
Educational Activity ◽  
City Center ◽  
Science And Culture ◽  
The University ◽  
The City

The article presents the results of a study of scientific, educational and ascetic activities of one of the brightest representatives of the modern Ukrainian diaspora in Russia - Tetiana Lebedynska, a daughter of Ukrainian writer Mykola Shpak. T.M. Lebedynska is PhD in Philosophy, translator, writer, member of the Ukrainian Union of Writers, author of exhibitions dedicated to Ukrainian St. Petersburg, holder of the Order of Princess Olga III degree. The multifaceted scientific and educational activity of Tetiana Mykolajivna is considered. It is emphasized that she initiated and organized the International Scientific Seminar «St. Petersburg – Ukraine», which resulted in the publication of twenty collections of articles from 2000 to 2020. T.M. Lebedynska is the author of more than 200 scientific works, including unique publications: «Shevchenko's places of St. Petersburg», «St. Petersburg and Ukraine», «M.P. Hrebinka - town-planning of St. Petersburg», «Ukrainian necropolis of St. Petersburg», «I. Mazepa - Commander of the Order of St. Andrew the First-Called», dictionary»Outstanding figures of science and culture of Russia who came from Ukraine», etc.. T.M. Lebedynska was published in Western Europe, the United States, and Arab countries. It is noted that the heroine of our intelligence pays most attention to the study of the life and work of the Great Kobzar, who had many life events in St. Petersburg: here he studied and worked, gained freedom and communicated with many prominent cultural figures, wrote poems and paintings and became an academician of arts. It was Tetiana Mykolajivna who was one of the initiators of the installation in St. Petersburg of the monument to Taras Shevchenko by Canadian sculptor Leo Mol (Leonid Molodozhanin), she collected signatures against the relocation of the site from the city center near the university to the outskirts, also she initiated and participated in the installation of a memorial to Kobzar at the Smolensk cemetery. Among other things Tetiana Lebedynska‟s ascetic activity is represented, by a study of the Ukrainian necropolis of St. Petersburg, as most graves and tombstones are in a state of destruction and may disappear for the future without restoration. And with them the memory of our compatriots who found eternal peace in the land of North Palmira will be destroyed. The article states that today, when Crimea is annexed and the Russian occupation of Donbass continues, it is very important to study the experience of our contemporaries - Ukrainians in Russia, who do not lose their identity in conditions of strong informational, ideological and linguistic pressure.

scholarly journals ANALISIS BAURAN PEMASARAN DI HOTEL PANGERAN BEACH PADANG

2018 ◽  
Vol 10 (1) ◽  
pp. 29
Author(s):  
Nurmala Widyastuti
Keyword(s):  
Sampling Technique ◽  
Marketing Mix ◽  
Upper Class ◽  
City Center ◽  
High Quality ◽  
Purposive Sampling ◽  
Travel Agents ◽  
The City ◽  
Hotel Marketing

Abstract. Based on this study to analyze the marketing mix at the Pangeran Beach Hotel Padang. This type of research is a qualitative descripptive. Determination of informants using purposive sampling technique that is many as eight research informants consisting of hotel marketing and hotel consumers. The results obtained from this study are as follows : 1) The products offered by the Pangeran Beach Hotel Padang are quality attractive and of high quality and the service provide to guests are good, 2) The Price set by the Pangeran Beach Hotel Padang is quite high and is only affordable for middle and upper class people, 3) Promotions carried out by the Pangeran Beach Hotel Padang have been maximized so that guests are still intererted in staying at the hotel, 4) The Place or location of the Pangeran Beach Hotel Padang is already strategic annd in the city center, and works together to travel agents so that guests know the location of the Pangeran Beach Hotel Padang. Keywords : Marketing, Marketing mix

Understanding the Shared E-scooter Travels in Austin, TX

2020 ◽  
Vol 9 (2) ◽  
pp. 135 ◽  
Author(s):  
Junfeng Jiao ◽  
Shunhua Bai
Keyword(s):  
Higher Education ◽  
Land Use ◽  
Operation Time ◽  
Street Connectivity ◽  
Travel Patterns ◽  
City Center ◽  
University Of Texas ◽  
The University ◽  
The Relationship ◽  
The City

This paper investigated the travel patterns of 1.7 million shared E-scooter trips from April 2018 to February 2019 in Austin, TX. There were more than 6000 active E-scooters in operation each month, generating over 150,000 trips and covered approximately 117,000 miles. During this period, the average travel distance and operation time of E-scooter trips were 0.77 miles and 7.55 min, respectively. We further identified two E-scooter usage hotspots in the city (Downtown Austin and the University of Texas campus). The spatial analysis showed that more trips originated from Downtown Austin than were completed, while the opposite was true for the UT campus. We also investigated the relationship between the number of E-scooter trips and the surrounding environments. The results show that areas with higher population density and more residents with higher education were correlated with more E-scooter trips. A shorter distance to the city center, the presence of transit stations, better street connectivity, and more compact land use were also associated with increased E scooter usage in Austin, TX. Surprisingly, the proportion of young residents within a neighborhood was negatively correlated with E-scooter usage.

scholarly journals The criterion of the presumption of biophysiological temperature and the cooling guide for the determination of human comfort in the City of Rutba

2018 ◽  
Vol 227 (2) ◽  
pp. 307-316
Author(s):  
Lect. Intisar Sukkar Khioun
Keyword(s):  
Relative Humidity ◽  
Solar Radiation ◽  
Climatic Data ◽  
Human Comfort ◽  
Air Movement ◽  
The Impact ◽  
The Relationship ◽  
The City ◽  
Climate Studies

     The relationship between man and climate is of great importance in climate studies, as climate is the most natural climatic element in the sense of comfort or distress of man, and humans can live comfortably if the degree of heat between (17-31 m) and the human feeling of heat and cold and then rest or discomfort not only caused by the air temperature but depends on many elements including solar radiation, air movement, relative humidity, the level of human activity and the type of clothing worn, and the presumption has used Biophysiological temperature and Cooling guide in this study to demonstrate the impact of climate on human comfort in the city of Rutba and relying on the climatic data for thirty years.

scholarly journals ANÁLISE DOS POLUENTES ATMOSFÉRICOS NO2 E O3 VIA AMOSTRADORES PASSIVOS DE BAIXO CUSTO

e-xacta ◽  
2017 ◽  
Vol 10 (1) ◽  
pp. 29
Author(s):  
Danielle Cristine Miranda ◽  
Gabriel Campos Ferreira ◽  
Larissa Domingues Barbosa ◽  
Nara Luíza Andrade Pereira ◽  
Tatiany Ciríaco Ribeiro ◽  
...  
Keyword(s):  
Factor Analysis ◽  
Data Analysis ◽  
Low Cost ◽  
Passive Samplers ◽  
Optimal Region ◽  
Paper Filter ◽  
Petri Dishes ◽  
Absorber Solution ◽  
The University

<p><em>O uso de equipamentos que monitorem a concentração de poluentes pode contribuir para prevenção de possíveis danos à saúde humana. Ess</em><em>e trabalho consiste no desenvolvimento de amostradores passivos de baixo custo para a determinação dos poluentes NO<sub>2</sub> e O<sub>3</sub> no campus Alto Paraopeba, através da análise fatorial e superfície de resposta. Os amostradores foram construídos em placas de Petri com filtros de papel contendo diferentes soluções absorvedoras para cada tipo de gás monitorado. Os amostradores de NO<sub>2</sub> foram expostos no refeitório da Universidade e os amostradores de O<sub>3</sub> foram expostos na sala de máquinas fotocopiadoras. Nos amostradores foram usadas diferentes quantidades de solução absorvedora e, também, diferentes tempos de exposição. Os resultados mostraram que a melhor condição para o NO<sub>2</sub> foi obtida com 4,6 mL de solução absorvedora e no tempo de 68 horas de exposição. Nessas condições, a concentração de NO<sub>2</sub> no Restaurante Universitário foi de 10,5 µg/m<sup>3</sup>. Para o ozônio, as concentrações variaram entre 4,2 µg/m<sup>3</sup> e 40 µg/m<sup>3</sup>, e a melhor condição (3 mL de solução absorvedora e tempo de 77 horas) está localizada no ponto sela e não na região ótima do gráfico. Isso ocorre devido ao fato do ozônio se decompor rapidamente a oxigênio.</em> <em>Os amostradores passivos apresentaram resultados satisfatórios e recomenda-se seu uso como uma alternativa de baixo custo para o monitoramento de NO<sub>2</sub> e O<sub>3</sub> no Restaurante Universitário e sala de Fotocopiadoras.  </em></p><p><em>ABSTRACT</em></p><em>The use of equipment that monitors the concentration of pollutants can contribute to the prevention of possible damages to human health. This work is to develop inexpensive passive samplers for the determination of NO<sub>2</sub> and O<sub>3</sub> pollution in the campus Alto Paraopeba beyond the optimization of analytical methods by software that provides a complete environment for data analysis; by factor analysis and response surface generated by it. The samplers were constructed on Petri dishes with paper filter containing different absorbing solutions according to each monitored gas. The samplers were exposed to NO<sub>2</sub> at university restaurant and others samplers were exposed to O<sub>3</sub> at the photocopier room of the campus. In samplers were used different amounts of absorber solution and also different exposure times. The results showed that the best condition for NO<sub>2</sub> was obtained with 4.6 mL of absorbing solution in time of 68 hours exposure. Under these conditions, the concentration of NO<sub>2</sub> in the university restaurant was 10.5 µg/m<sup>3</sup>. For ozone, the concentrations ranged from 4.2 µg/m<sup>3</sup> and 40 µg/m<sup>3</sup>, and the best condition (3 mL absorbing solution and time of 77 hours) is located at saddle point and not at the optimal region of the graph. This is because ozone has rapidly decomposes to oxygen. Passive samplers presented satisfactory results and it is recommended to use them as a low cost alternative for the monitoring of NO<sub>2</sub> and O<sub>3</sub> in the University Restaurant and Photocopiers room.</em>

scholarly journals ANALISIS PENETAPAN NILAI JUAL OBJEK PAJAK TERHADAP PENERIMAAN PAJAK BUMI DAN BANGUNAN DI KABUPATEN MINAHASA TENGGARA

2015 ◽  
Vol 4 (1) ◽  
pp. 140
Author(s):  
Nola Lavenia Watak
Keyword(s):  
Local Government ◽  
Central Government ◽  
Economic Value ◽  
Property Tax ◽  
City Center ◽  
Strategic Location ◽  
High Contribution ◽  
The City ◽  
Descriptive Method

Property Tax is one tax which is managed by the local government. Which is the only property tax in Indonesia, because most of the revenue is income areas, among others, are also used for the provision of facilities enjoyed by the central government and local government. Bases of land and building tax is the taxable value. The purpose of this study is to analyze Determination of taxable value against land and building tax in Southeast Minahasa Regency. The object of this research is 3 Southeast Minahasa District in the District Ratahan, District Pasan, and the District of East Ratahan. The data collection techniques in this study is a field study in the Department of Revenue in Southeast Minahasa regency. This research uses descriptive method. Based on the research results, the authors concluded that the three districts are districts Ratahan, Pasan, and Ratahan East where the districts are located in the city center in Southeast Minahasa Regency, strategic location and generates economic value. So it has a high contribution to the reception in Southeast Minahasa regency. Department of Revenue is responsible for determining the tax object selling value needs to improve the assessment and pengelolahan data, especially between the sale value of the tax object selling prices that occurred in the community so that more relevant determination.

scholarly journals Determination of Temporary Shelter Areas by the Analytic Hierarchy Process Method: The Case of Burdur City Center, Turkey

2021 ◽  
Vol 9 (4) ◽  
pp. 807-813
Author(s):  
Hüseyin Samet Aşıkkutlu ◽  
Yasin Aşık ◽  
Latif Gürkan Kaya
Keyword(s):  
Analytic Hierarchy Process ◽  
Human Life ◽  
City Center ◽  
Analytic Hierarchy ◽  
Analytic Hierarchy Process Method ◽  
Hierarchy Process ◽  
The City ◽  
Post Disaster ◽  
Process Method

Disasters adversely affect human life. Many people face sheltering problems after disasters. Temporary shelter areas are very important in terms of meeting people's post-disaster sheltering needs. In this study, it was aimed to determine temporary shelter areas in the city center of Burdur. The AHP (Analytic Hierarchy Process) method was used to determine temporary shelter areas. According to certain criteria and spatial standards, six temporary shelter areas were determined in the city center of Burdur, and their adequacy was tested. Temporary shelters are located in urban open and green lands. Temporary shelter areas determined under today's conditions are adequate. However, it is predicted that temporary shelter areas will be inadequate in the upcoming process. Some recommendations were made about the problems and the path to be followed in the upcoming process. These recommendations will be useful for the post-disaster process.

scholarly journals DETERMINATION OF SOIL QUALITY IN MAYKOP BASED ON THE CONTENT ANALYSIS OF SOIL ALGAE AND CYANOBACTERIA

2017 ◽  
Vol 14 ◽  
pp. 128-135
Author(s):  
Emiliya A. Sirotiuk ◽  
Saida R. Zhemadukova
Keyword(s):  
Heavy Metals ◽  
Soil Contamination ◽  
Soil Quality ◽  
Oil Products ◽  
City Center ◽  
Key Indicator ◽  
City District ◽  
Destructive Processes ◽  
The City

The paper presents the results of the study on soil quality in Maykop using algae indication. The findings suggest soil contamination by heavy metals and oil products, and the beginning of destructive processes. The city center is recognized to be the most unfavorable ecological area of the city. There are no diatoms in soil cyanoalgological sinusiae ‒ a key indicator of oil contamination of soils. On the contrary, cyanobacteria prevail, which are resistant to soil contamination with oil products and heavy metals. One of the main environmental problems in Maykop is soil contamination with heavy metals and oil products. The main contributor to soil contamination is city transport and housing and public services. Pollutants enter soil through precipitation and leaf and branch shedding, deposit from the air, and are directly absorbed by moist soil. The results of algological studies suggest that destructive processes have begun in the soils in Maykop. This is evidenced by the composition of soil cyanoalgological sinusiae and by the population of main groups of microphototrophs. The most ecologically disadvantaged city district is «Central Market».

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