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In this study, the exposure to ambient particulate matter metrics (PM1, PM2.5, PM10, black carbon (BC), brown carbon (BrC), ultraviolet particulate matter (UVPM), particle number concentration (PNC), and lung deposited surface area (LDSA)) were measured along a fixed walking route with specific focus on three typical micro-environments (park, central business district (CBD), and traffic) in different time of day during the non-heating (May–Oct.) and heating (Nov.–Apr.2nd year) periods from 2018 to 2020 in the downtown Augsburg, Germany. The spatio-temporal exposure to ambient PM metrics exhibited substantial heterogeneity during the observation period, with park environment having lowest exposure and traffic area having the highest exposure. Generally, the higher LDSA concentrations were found in traffic area and CBD during the observation periods, while the lower concentrations were found in the park, which is similar with other ambient PM metrics (PMX, eUVPM, eBC, and PNC). The correlations between LDSA and other ambient PM metrics were higher during the heating than non-heating period in most of investigated environments, indicating the different PM sources. Overall, this study provides a comprehensive assessment of personal exposure that complements fixed-site ambient PM metrics measurements in the context of health risk assessment and epidemiological studies., The work is funded by National Natural Science Foundation of China (42101470), the Research Project of the Ministry of Science and Technology of China (2019YFC0507800), the Germany Federal Ministry of Transport and Digital Infrastructure (BMVI) as part of SmartAQnet (19F2003B), the Support Project of High-level Teachers in Beijing Municipal Universities in the Period of 13th Five - year Plan (CIT&TCD201904037), and the China Scholarship Council (CSC) under the State Scholarship Fund (201706860028), and Peiyang Future Scholar Scholarship (6120000246).

This paper presents the results of investigations of the impact of parabolic pulsed heating on output voltage levels of a thermoelectric generator. The experiment was set up and tested under different test conditions. The output voltage levels were investigated. The experimental results showed that applying parabolic pulsed heating of 40, 60, 80 and 100 °C significantly maintained the output voltage levels of thermoelectric generator at about 80-95% which was different from steady heating case which was about 10-30% of maximum voltage level. Moreover, the parabolic pulse heating technique allows the heatsink to not be heated continuously and then the high temperature could be released out from a heat exchanger outside the heating period. This causes the next heating period to have a temperature difference between both sides of the device, and for that reason, could provide more power and efficiency.

Панферов Сергей Владимирович, кандидат технических наук, доцент кафедры градостроительства, инженерных сетей и систем, Южно-Уральский государственный университет (Челябинск), panferovsv@susu.ru. S.V. Panferov, panferovsv@susu.ru South Ural State University, Chelyabinsk, Russian Federation Введение. Проблема энергосбережения в жилищно-коммунальной сфере является актуальнейшей проблемой настоящего времени, ее решение возможно в том числе и за счет рационального выбора технического состава котельной установки, поэтому рассмотрение вопросов проектирования котельных является важной задачей. Цель исследования. Рассмотреть задачу выбора количества и мощности котлов для проектируемого источника теплоснабжения. Материалы и методы. Проанализированы известные в литературе способы решения данной проблемы. Указано, что поставленная задача является весьма сложной прежде всего из-за ее многокритериальности и что в литературе по ее решению имеются рекомендации в основном качественного характера. Результаты. Предложена новая формализованная методика расчета, включающая три варианта решения этой задачи. Установлено, что количество котлов в котельной во всех трех вариантах расчета совсем не зависит от расчетной тепловой нагрузки, а определяется только расчетной и допустимой температурами внутреннего воздуха, а также расчетной и средней за отопительный период температурами наружного воздуха. Большее количество котлов получается при расчете по первому варианту, а меньшее – при расчете по третьему варианту, поэтому первый вариант является предпочтительным в том смысле, что при его реализации вполне возможен номинальный или близкий к номинальному режим работы котлов в течение всего отопительного периода. Достигается это за счет изменения числа включенных в работу котлов. Второй вариант решения задачи предусматривает установку в котельной двух типов котлов, в двух других вариантах котлы однотипные. Примечательно, что номи- нальная мощность котлов, рассчитанных по первому варианту, равна номинальной мощности котлов, рассчитанных по второму варианту для условий работы при средней наружной температуре отопительного периода. Номинальная мощность дополнительного котла для второго варианта равна номинальной мощности котлов для третьего варианта расчета. Заключение. Разработанная методика позволяет упорядочить процедуру выбора возможных вариантов технического состава котельной, сокращает число таких возможных вариантов, что в последующем при экономическом анализе, а также и в целом при проектировании способствует уменьшению объема вычислительной работы. Методика апробирована на конкретном примере и рекомендуется для использования при решении проектных задач. Introduction. The problem of energy saving in the housing and communal services sector is the most urgent problem of the present time; its solution is possible, including through a rational choice of the technical composition of the boiler plant. Therefore, consideration of the boiler design issues is an important task. Objective. Consider the task of choosing the number and capacity of boilers for the designed heat supply source. Materials and methods. The methods for solving this problem, which are available in the literature, are analyzed. It is indicated that the task is very difficult, primarily because of its multicriteria, and that in the literature on its solution there are recommendations mainly of a qualitative nature. Results. A new formalized calculation method is proposed, which includes three options for solving this problem. It is established that the number of boilers in the boiler room in all three calculation options does not at all depend on the calculated heat load, but is determined only by the calculated and permissible internal air temperatures, as well as by the calculated and average outdoor temperatures for the heating period. A larger number of boilers is obtained when calculating according to the first option, and a smaller number when calculating according to the third option; therefore, the first option is preferable in the sense that when it is implemented, it is possible to have a nominal or close to nominal mode of operation of the boilers during the entire heating period. This is achieved by changing the number of boilers included in the operation. The second solution to the problem involves the installation of two types of boilers in the boiler room, and in the other two versions the boilers are of the same type. It is noteworthy that the rated power of the boilers calculated according to the first option is equal to the rated power of the boilers calculated according to the second option for operating conditions at an average outdoor temperature of the heating period. The rated power of the additional boiler for the second option is equal to the rated power of the boilers for the third calculation option. Conclusion. The developed technique allows to streamline the procedure for selecting possible options for the technical composition of a boiler room, reduces the number of such possible options, what subsequently (during the economic analysis, as well as, in general, when designing) helps to reduce the amount of computational work. The technique has been tested on a specific example and is recommended for use in solving design problems.

Exposure to polycyclic aromatic hydrocarbons (PAHs) may lead to adverse health risks. To understand the potential sources and carcinogenic risks of PAHs in Tangshan, 40 PM2.5 samples were collected for analysis of eighteen PM2.5-bound PAHs during non-heating period and heating period. The results display a significant variation. The median concentration of ∑18PAHs during the heating period (282 ng/m3) was higher than during the non-heating period (185 ng/m3). Especially, the median concentration of Benzopyrene (BaP) during the heating period (61.6 ng/m3) was 16.9-fold that during the non-heating period (3.64 ng/m3). It exceeded BaP annual average limit of China (1 ng/m3). Diagnostic ratios (DRs) and principal component analysis (PCA) both indicated that vehicle emissions and coal and biomass combustion were the dominant contributors of PAHs pollution in Tangshan. The incremental lifetime cancer risk (ILCR) of three age groups (children, teenagers, and adults) ranged from 2.56 × 10−6 to 5.26 × 10−5 during the entire sampling periods. The 95% risk values of adults exceeded 10−4 during the heating periods, indicating a potential health risk from PAHs.

PM2.5 and PM10 samples were collected from the outdoor environment of five types of cities (provincial central cities, regional central cities, resource-based cities, agricultural cities, and forested cities) situated in Northeast China. Based on bioaccessibility and respiratory deposition fluxes, health risks of PM2.5- and PM10-bound six heavy metals [HM6: Arsenic (As), Chromium (Cr), Cadmium (Cd), Nickel (Ni), Cobalt (Co), and Lead (Pb)] were studied. Cobalt (Co) and Cr were found to be the most abundantly bioaccessible fraction among HM6 after extraction of simulated lung fluids. After inhalation exposure, among HM6, Co mainly contributed 88.39–93.19% to the non-carcinogenic risk, while Cr account for 82.92–93.72% of cancer risk. The estimated daily intake of bioaccessible HM6 in outdoor environment during the heating period was calculated to be 293.11 ± 121.03, 117.08 ± 32.46, 105.57 ± 32.49, 100.35 ± 25.58 and 83.11 ± 17.64 ng/h for provincial central cities, regional central cities, agricultural city, resource-based cities and forested cities, respectively, for local residents. During the heating period of 180 days, non-carcinogenic risks (As, Cr, Cd, Ni, Co) in outdoor environment of 0.5 residence time were below the safety threshold (HQ

In this study, a three-dimensional transient numerical analysis was performed inside the automobile cabin during heating period. A three-dimensional vehicle cabin including glazing surfaces was modeled by using the real dimensions of a car. A virtual manikin with real dimensions and physiological shape was added to the model of the vehicle cabin. It was assumed that the manikin surfaces were subjected to either constant heat flux or constant temperature. Three-dimensional fluid flow, temperature distribution, and heat transfer characteristics inside the cabin were calculated. Experimental measurements were also conducted. Comparisons of the results were presented and discussed. The results of numerical calculations were in good agreement with the experimental and theoretical data in the literature. FIAT-TOFAS

In this article, we consider results of performed research, dedicated to assessment of changes in parameters of heating period (HP) of Volga Federal District (VFD). For the first time for territory of VFD we created maps for space distribution of the main characteristics of heating period; we investigated peculiarities of multiannual dynamics of characteristics of heating period that had been previously unknown, and we assessed their multiannual tendencies; for the first time for VFD we tested tightness and directionalities of interconnections between various characteristics of heating period and estimated perspectives of the application for prognostic aims. It was stated that climate indices of heating period was characterized by high level of variability in both time and territory of the district. Temporary instability of climatic indices of heating period within the territory of the district increase at a high pace from its southern parts in the direction of North and North-East, where it reaches its maximal values, which is non-stochastic. We detected the presence of rather tight and significant connections between the dates of autumn switches of mean daily air temperature (MDAT) through 8°C and the length, which opens possibility of building one-factor regressive prognostic models with significant resolving capacity at coefficient of their determination of [R2(O,Π)]=38÷52%.

International audience; Vaporization and oxidation of liquid fuel droplets are basic mechanisms in spray combustion for various industrial applications. In this work, coupledeffects of temperature and pressure on n-alkane droplet vaporization are investigated in experiments conducted in a high-pressure and high-temperature gasification facility equipped with the fiber-suspended droplet technique. The influence of temperature and pressure on n-heptane and n-decane vaporization rates is particularly emphasized with regard to critical conditions of the liquid fuel. Characteristics of n-alkane droplet vaporization, and heating and vaporization times are compared with those of vegetable oil methyl esters—biofuels used in diesel engines. Finally, chemical species formed during the oxidation of these biofuels are identified by gas chromatography in oxidation experiments performed in a jet-stirred reactor. The influence of temperature, pressure, and equivalence ratio on regulated and unregulated pollutants is discussed. Emissions of pollutants obtained during biofuels oxidation are compared with those identified during the oxidation of a synthetic diesel fuel.

This paper describes a combined theoretical and experimental study of thermal comfort during the heating period inside an automobile. To investigate the effects of thermal conditions on the human physiology and thermal comfort during the heating period, temperature, humidity and air velocity were measured at a number of points inside the automobile, so thermal conditions were accurately determined. The human body was divided into 16 sedentary segments, and the change of temperature was observed both experimentally and theoretically. During transient conditions of the heating period, heat and mass transfer between the human body and the interior environment of an automobile were simulated by a computational model, and predictions were compared with the measured data. It is shown that there is a good agreement between the model predictions and experimental results. By means of the present model, the effects of the fast transient conditions of the heating period on the sensible and latent heat transfer from the body, body segments skin temperatures and thermal sensation were investigated in detail.