scholarly journals Intercomparison study of six HTDMAs: results and general recommendations for HTDMA operation

2008 ◽  
Vol 1 (1) ◽  
pp. 127-168 ◽  
Author(s):  
J. Duplissy ◽  
M. Gysel ◽  
S. Sjogren ◽  
N. Meyer ◽  
N. Good ◽  
...  

Abstract. We report on an intercomparison of six different hygroscopicity tandem differential mobility analysers (HTDMAs). These HTDMAs are used worldwide in laboratory experiments and field campaigns to measure the water uptake of aerosol particles and were never intercompared. After an investigation of the different design of the instruments with their advantages and inconveniencies, the methods for calibration, validation and data analysis are presented. Measurements of nebulised ammonium sulphate as well as of secondary organic aerosol generated from a smog chamber were performed. Agreement and discrepancies between the instrument and to the theory are discussed, and final recommendations for a standard instrument are given, as a benchmark for laboratory or field experiments to ensure a high quality of HTDMA data.

2009 ◽  
Vol 2 (2) ◽  
pp. 363-378 ◽  
Author(s):  
J. Duplissy ◽  
M. Gysel ◽  
S. Sjogren ◽  
N. Meyer ◽  
N. Good ◽  
...  

Abstract. We report on an intercomparison of six different hygroscopicity tandem differential mobility analysers HTDMAs). These HTDMAs are used worldwide in laboratory experiments and field campaigns to measure the water uptake of aerosol particles and have never been intercompared. After an investigation of the different design of the instruments with their advantages and inconveniencies, the methods for calibration, validation and data analysis are presented. Measurements of nebulised ammonium sulphate as well as of secondary organic aerosol generated from a smog chamber were performed. Agreement and discrepancies between the instruments and to the theory are discussed, and final recommendations for a standard instrument are given, as a benchmark for laboratory or field experiments to ensure a high quality of HTDMA data.


2021 ◽  
Vol 244 ◽  
pp. 02046
Author(s):  
Jonibek Khudaykulov ◽  
Sarvinoz Togaeva ◽  
Chulpanoy Kashkabaeva ◽  
Zayniddin Abirov ◽  
Shukhrat Shodmonov

In this article, the analysis of the field experiments conducted in the Tashkent province, which was aimed at improving the technology of high-quality production, and economic efficiency of peanuts in the conditions of the typical gray soil and climate, was given. In the field experiments, the effect of Microzym-2 biostimulator on growth, development, yield elements, yield and seed quality of local peanut varieties “Salomat” (standard) and “Mumtoz” was studied. Accordingly, before sowing of peanut seeds, the biostimulator Microzym-2 was applied at a rate of 30 l/t, as result the yield of legumes was 1.4 t/ha higher in “Salomat” (standard) and 1.1 t/ha higher in the class “Mumtoz” than in the control variant (11.7 t/ha). When peanut varieties were supplemented with mineral fertilizers N150P150K100 kg/ha, and treated with Microzym-2 biostimulator before the sowing and during the flowering periods, 29.3 q/ha of “Salomat” variety and 33.2 q/ha of “Mumtoz” harvest were obtained. It was found that Microzym-2 biostimulator in sowing peanuts was cost-effective.


2010 ◽  
Vol 10 (11) ◽  
pp. 27893-27924 ◽  
Author(s):  
M. A. Miracolo ◽  
C. J. Hennigan ◽  
M. Ranjan ◽  
N. T. Nguyen ◽  
T. D. Gordon ◽  
...  

Abstract. Field experiments were performed to investigate the effects of photo-oxidation on fine particle emissions from an in-use CFM56-2B gas turbine engine mounted on a KC-135 Stratotanker airframe. Emissions were sampled into a portable smog chamber from a rake inlet installed one-meter downstream of the engine exit plane of a parked and chocked aircraft. The chamber was then exposed to sunlight and/or UV lights to initiate photo-oxidation. Separate tests were performed at different engine loads (4, 7, 30, 85%). Photo-oxidation created substantial secondary particulate matter (PM), greatly exceeding the direct PM emissions at each engine load after an hour or less of aging at typical summertime conditions. After several hours of photo-oxidation, the ratio of secondary-to-primary PM mass was on average 35 ± 4.1, 17 ± 2.5, 60 ± 2.2, and 2.7 ± 1.1 times the primary PM for the 4, 7, 30, and 85% load experiments, respectively. The composition of secondary PM formed strongly depended on load. At 4% load, secondary PM was dominated by secondary organic aerosol (SOA). At higher loads, the secondary PM was mainly secondary sulfate. Predictions of an SOA model are compared to the measured SOA formation. The SOA model predicts ~40% of the SOA produced during the 4% load experiment and ~60% for the 85% load experiment. Significant emissions of low-volatility compounds present in both the vapor- and particle-phase were measured in the exhaust and represent a significant pool of SOA precursors that appear to form SOA efficiently when oxidized. These results underscore the importance of accounting for atmospheric processing when assessing the influence of aircraft emissions on ambient PM levels.


2017 ◽  
Vol 10 (3) ◽  
pp. 1169-1179 ◽  
Author(s):  
Sandro M. Oswald ◽  
Helga Pietsch ◽  
Dietmar J. Baumgartner ◽  
Philipp Weihs ◽  
Harald E. Rieder

Abstract. This study investigates the effects of ambient meteorology on the accuracy of radiation (R) measurements performed with pyranometers contained in various heating and ventilation systems (HV-systems). It focuses particularly on instrument offsets observed following precipitation events. To quantify pyranometer responses to precipitation, a series of controlled laboratory experiments as well as two targeted field campaigns were performed in 2016. The results indicate that precipitation (as simulated by spray tests or observed under ambient conditions) significantly affects the thermal environment of the instruments and thus their stability. Statistical analyses of laboratory experiments showed that precipitation triggers zero offsets of −4 W m−2 or more, independent of the HV-system. Similar offsets were observed in field experiments under ambient environmental conditions, indicating a clear exceedance of BSRN (Baseline Surface Radiation Network) targets following precipitation events. All pyranometers required substantial time to return to their initial signal states after the simulated precipitation events. Therefore, for BSRN-class measurements, the recommendation would be to flag the radiation measurements during a natural precipitation event and 90 min after it in nighttime conditions. Further daytime experiments show pyranometer offsets of 50 W m−2 or more in comparison to the reference system. As they show a substantially faster recovery, the recommendation would be to flag the radiation measurements within a natural precipitation event and 10 min after it in daytime conditions.


2016 ◽  
Author(s):  
Sandro M. Oswald ◽  
Helga Pietsch ◽  
Dietmar J. Baumgartner ◽  
Philipp Weihs ◽  
Harald E. Rieder

Abstract. This study investigates effects of ambient meteorology on the accuracy of radiation measurements performed with pyranometers contained in various heating/ventilation systems (HV-systems). It focuses particularly on instrument offsets observed following precipitation events. To quantify pyranometer responses to precipitation, a series of controlled laboratory experiments as well as two targeted field campaigns were performed in 2016. The results indicate that precipitation (as simulated by spray-tests or observed under ambient conditions) significantly affects the thermal environment of the instruments and thus their stability. Statistical analysis of laboratory experiments showed that precipitation triggers zero offsets of −4 W m−2 or more, independent of the HV-system. Similar offsets have been observed in field experiments under ambient environmental conditions, indicating a clear exceedance of BSRN targets following precipitation events. All pyranometers required substantial time to return to their initial signal states after the simulated precipitation events. Therefore for BSRN standard measurements the recommendation would be to flag the radiation measurements during a natural precipitation event and 90 min after it in nighttime conditions. Further daytime experiments show pyranometer offsets of 50 W m−2 or more in comparison to the reference system. As they show a substantially faster recovery, the recommendation would be to flag the radiation measurements within a natural precipitation event and 10 min after it in daytime conditions.


Author(s):  
A. T. Kunakbaeva ◽  
A. M. Stolyarov ◽  
M. V. Potapova

Free-cutting steel gains specific working properties thanks to the high content of sulfur and phosphorus. These elements, especially sulfur, have a rather high tendency to segregation. Therefore, segregation defects in free-cutting steel continuously cast billets can be significantly developed. The aim of the work was to study the influence of the chemical composition of freecutting steel and casting technological parameters on the quality of the macrostructure of continuously cast billets. A metallographic assessment of the internal structure of cast metal made of free-cutting steel and data processing by application of correlation and regression analysis were the research methods. The array of production data of 43 heats of free-cutting steel of grade A12 was studied. Steel casting on a five-strand radial type continuous casting machine was carried out by various methods of metal pouring from tundish into the molds. Metal of 19 heats was poured with an open stream, and 24 heats – by a closed stream through submerged nozzles with a vertical hole. High-quality billets had a cross-sectional size of 150×150 mm. The macrostructure of high-quality square billets made of free-cutting steel of A12 grade is characterized by the presence of central porosity, axial segregation and peripheral point contamination, the degree of development of which was in the range from 1.5 to 2.0 points, segregation cracks and strips – about 1.0 points. In the course of casting with an open stream, almost all of these defects are more developed comparing with the casting by a closed stream. As a result of correlation and regression analysis, linear dependences of the development degree of segregation cracks and strips both axial and angular on the sulfur content in steel and on the ratio of manganese content to sulfur content were established. The degree of these defects development increases with growing of sulfur content in steel of A12 grade. These defects had especially strong development when sulfur content in steel was of more than 0.10%. To improve the quality of cast metal, it is necessary to have the ratio of the manganese content to the sulfur content in the metal more than eight.


2020 ◽  
pp. 52-58 ◽  
Author(s):  
A. A. Eryomenko ◽  
N. V. Rostunova ◽  
S. A. Budagyan ◽  
V. V. Stets

The experience of clinical testing of the personal telemedicine system ‘Obereg’ for remote monitoring of patients at the intensive care units of leading Russian clinics is described. The high quality of communication with the remote receiving devices of doctors, the accuracy of measurements, resistance to interference from various hospital equipment and the absence of its own impact on such equipment were confirmed. There are significant advantages compared to stationary patient monitors, in particular, for intra and out-of-hospital transportation of patients.


2018 ◽  
pp. 26-35
Author(s):  
Z. A. Agaeva ◽  
K. B. Baghdasaryan

The transthoracic echocardiography made by multifrequency probes with support of the mode of the second harmonic imaging, is a competitive method for visualization of the main coronary arteries and allows to estimate coronary blood flow with high quality. Of course, the method has considerable restrictions, most important of which is the low spatial resolution of a method, due to small acoustic window. Because of this the transthoracic visualization of coronary arteries perhaps will not become the leading method of anatomic reconstruction of separately taken coronary artery and especially all coronary arteries system. However uniqueness and indisputable advantage of this method is an opportunity to noninvasively estimate a coronary blood flow both once, and in dynamics.


2020 ◽  
Vol 18 (4) ◽  
pp. 739-752 ◽  
Author(s):  
R.M. Sadykov

Subject. This article deals with the issues of social justice and a high quality of life, creating favorable economic and social conditions. Objectives. The article aims to assess the rate and changes in poverty in Russia and the Republic of Bashkortostan and develop complementary measures to reduce it. Methods. For the study, I used the methods of logical, comparative, economic and statistical analyses, the results of sociological studies, and official statistics. Results. The article highlights additional measures to reduce poverty in the region, including the establishment of a minimum social standard of living in each particular region that determines the poverty rate. Conclusions. Various factors, such as economic sanctions, economic slowdowns, territorial and regional imbalances, lead to living standards decline and poverty rise.


Author(s):  
La Duc Minh ◽  
Nguyen Thi Hao ◽  
Vu Thi Thuy

Ethnic affairs play an important role in socio of ethnic groups’ solidarity, assurance of security and national defense stability. In -economic development, maintenanceorder to improve the quality of ethnic affairs, it is practical to carry out postgraduate training of officer implementing ethnic affairs using state budget with the aim of encouraging and enhancing officer quality to satisfy high-quality human resource in international integration.


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