ALBERT

Beschreibung: Desert coolers have attracted much attention as an alternative to mechanical air conditioning systems, as they are proving to be of lower initial cost and significantly lower operating cost. However, the uncontrolled increase in the moisture content of the supply air is still a great issue for indoor air quality and human thermal comfort concerns. This paper represents an experimental and numerical investigation of a modified desert air cooler into a liquid desiccant air conditioner (LDAC). An experimental setup was established to explore the supply air properties for an adapted commercial desert cooler. Several experiments were performed for air–water and air–desiccant as flow media, at several solutions to air mass ratios. Furthermore, the experimental results were compared with the result of a numerical simplified effectiveness model. The outcomes indicate a sharp reduction in the air humidity ratio by applying the desiccant solutions up to 5.57 g/kg and up to 4.15 g/kg, corresponding to dew point temperatures of 9.5 °C and 12.4 °C for LiCl and CaCl2, respectively. Additionally, the experimental and the numerical results concurred having shown the same pattern, with a maximal deviation of about 18% within the experimental uncertainties.

Beschreibung: In the process of economic urbanization, because of competition among cities, agglomerations and polarization of regional economies are produced. This paper studies the urban polarization with Chinese characteristics and the regional economic urbanization, which include the imbalance under the influence of different geographical factors between the east and west of China and the imbalance under the comprehensive influence of natural and human factors in the province. The urban economic polarization index (UEPI) is constructed to describe the regional imbalance caused by the economic polarization of capital cities in China. The purpose is to explore the polarization of provincial capitals in their respective provinces and to reveal the strength and evolution of their role in the imbalance of economic urbanization. Then, combined with relevant analysis of natural and socio-economic background data, the induced factors and the mechanism of urban polarization are diagnosed. The results show the following: (1) The UEPI can accurately measure the polarization level of provincial capitals through the calculation of typical cities. (2) Based on the UEPI, capital cities can be divided into four categories, which include inapparent, obvious, prominent, and striking. Different cities have different effects on the imbalance in economic urbanization. (3) The main inducing factors of urban polarization are the resource environment, policy system, industrial structure, investment, scientific and technological innovation, location, and extroversion. The policy system is often an important link that integrates and adjusts various factors to form a comprehensive driving mechanism.

Beschreibung: Constructing a knowledge graph of geological hazards literature can facilitate the reuse of geological hazards literature and provide a reference for geological hazard governance. Named entity recognition (NER), as a core technology for constructing a geological hazard knowledge graph, has to face the challenges that named entities in geological hazard literature are diverse in form, ambiguous in semantics, and uncertain in context. This can introduce difficulties in designing practical features during the NER classification. To address the above problem, this paper proposes a deep learning-based NER model; namely, the deep, multi-branch BiGRU-CRF model, which combines a multi-branch bidirectional gated recurrent unit (BiGRU) layer and a conditional random field (CRF) model. In an end-to-end and supervised process, the proposed model automatically learns and transforms features by a multi-branch bidirectional GRU layer and enhances the output with a CRF layer. Besides the deep, multi-branch BiGRU-CRF model, we also proposed a pattern-based corpus construction method to construct the corpus needed for the deep, multi-branch BiGRU-CRF model. Experimental results indicated the proposed deep, multi-branch BiGRU-CRF model outperformed state-of-the-art models. The proposed deep, multi-branch BiGRU-CRF model constructed a large-scale geological hazard literature knowledge graph containing 34,457 entities nodes and 84,561 relations.

Beschreibung: Ocean polymetallic nodules are oxide ores rich in Ni, Co, Cu, and Mn, which are valuable metals found in deep-sea mineral resources. Such non-ferrous metals do not exist in isolation, and producing concentrates using conventional mineral separation techniques is challenging without pre-treatment. We propose an effective, environmentally-friendly recovery technology combined with solid-state metalized reduction treatment and magnetic separation to recycle these metals from ocean polymetallic nodules. We conducted single-factor tests to investigate the effects of additives, anthracite dosage, duration, and reduction temperature on metal recovery and to obtain optimal operating parameters. We found that valuable metals in ocean polymetallic nodules may be selectively reduced to a metallic state. Only a fraction of Mn was reduced to metal. The reduced metals were recovered to concentrates using magnetic separation. More than 80% of these metals were concentrated to magnetic concentrates with mass ratios of 10–15%. The recovery rates of Ni, Co, Cu, Mn, and Fe in concentrates were optimum at 86.48%, 86.74%, 83.91%, 5.63%, and 91.46%, respectively, when using CaF2 4%, anthracite 7%, SiO2 dosage 5%, and FeS 6% at 1100 °C for 2.5 h. This approach to non-ferrous metal extraction using conventional hydrometallurgical processes could be a step toward practical industrial-scale techniques for the recovery of metals from polymetallic nodules.

Beschreibung: Climate change, air pollution, and the rapidly aging population are important public health challenges. An understanding of air pollution impacts is imperative for preventing air-pollution-related deaths and illnesses, particularly in vulnerable subgroups such as the increasing population of older adults. To assess the effects of short-term air-pollution exposure on the elderly, we conducted a time-series analysis (1996–2015) of the associations between particulate matter with an aerodynamic diameter of

Beschreibung: To clarify the aerosol optical properties under different pollution levels and their impacting factors, hourly organic carbon (OC), elemental carbon (EC), and water-soluble ion (WSI) concentrations in PM2.5 were observed by using monitoring for aerosols and gases (MARGA) and a semicontinuous OC/EC analyzer (Model RT-4) in Wuhan from 9 to 26 January 2018. The aerosol extinction coefficient (bext) was reconstructed using the original Interagency Monitoring of Protected Visual Environment (IMPROVE) formula with a modification to include sea salt aerosols. A good correlation was obtained between the reconstructed bext and measured bext converted from visibility. bext presented a unimodal distribution on polluted days (PM2.5 mass concentrations 〉 75 gm−3), peaking at 19:00. bext on clean days (PM2.5 mass concentrations 〈 75 gm−3) did not change much during the day, while on polluted days, it increased rapidly starting at 12:00 due to the decrease of wind speed and increase of relative humidity (RH). PM2.5 mass concentrations, the aerosol scattering coefficient (bscat), and the aerosol extinction coefficient increased with pollution levels. The value of bext was 854.72 Mm−1 on bad days, which was 4.86, 3.1, 2.29, and 1.28 times of that obtained on excellent, good, acceptable, and poor days, respectively. When RH 〈 95%, bext exhibited an increasing trend with RH under all pollution levels, and the higher the pollution level, the bigger the growth rate was. However, when RH 〉 95%, bext on acceptable, poor and bad days decreased, while bext on excellent and good days still increased. The overall bext in Wuhan in January was mainly contributed by NH4NO3 (25.2%) and organic matter (20.1%). The contributions of NH4NO3 and (NH4)2SO4 to bext increased significantly with pollution levels. On bad days, NH4NO3 and (NH4)2SO4 contributed the most to bext, accounting for 38.2% and 27.0%, respectively.

Beschreibung: Considering the wide range of variability of all aerosol characteristics (especially in the near-ground layer of the atmosphere near industrial centers), when creating a realistic empirical model of optical and microphysical characteristics, the optimal dividing of the total data array according to some multifactor signs is needed. In this paper, we analyze the main states of “dry” aerosol on the basis of the results of long-term regular measurements in the near-ground layer of the atmosphere near the city of Tomsk in 2000–2017. The following parameters were considered: aerosol number concentration and size distribution function, total and angular scattering coefficients, including the small-angle range 1.2° to 20°, mass concentration and size distribution of absorbing substances (equivalent black carbon), characteristics of the aerosol hygroscopic properties, and spectral aerosol extinction of radiation on an open long path in the wavelength range 0.45 to 3.9 µm. In our comprehensive study, we first proposed and developed an original approach (classification) to study the optical and microphysical properties of atmospheric aerosol of various physicochemical origins (background, smoke, smog, anthropogenic, etc.) based on dividing the entire data array into characteristic subarrays (types of aerosol weather), which differ from each other in a different combination of scattering and absorbing properties of particles. To divide the total data array into types of aerosol weather including “Background”, “Haze-S”, “Smog”, and “Smoke haze”, the values of the scattering coefficient of the dry aerosol matter σd(λ = 0.51 μm) = 100 Mm−1 and the ratio of the mass concentration of the absorbing substance to the mass concentration of submicron aerosol P = 0.05. The results showed that most of the seasonal average values of the aerosol parameters analyzed in the paper are statistically significantly different when comparing various characteristic types of scattering and absorbing atmospheric aerosol. The results of the research indicate that the application of the developed classification of types of aerosol weather for the analyzed optical and microphysical parameters of aerosol particles is quite effective and reasonable.

Beschreibung: Large-scale atmospheric pollutant spreading via volcano eruptions and industrial accidents may have serious effects on our life. However, many students and non-experts are generally not aware of the fact that pollutant clouds do not disperse in the atmosphere like dye blobs on clothes. Rather, an initially compact pollutant cloud soon becomes strongly stretched with filamentary and folded structure. This is the result of the chaotic behaviour of advection of pollutants in 3-D flows, i.e., the advection dynamics of pollutants shows the typical characteristics such as sensitivity to the initial conditions, irregular motion, and complicated but well-organized (fractal) structures. This study presents possible applications of a software called RePLaT-Chaos by means of which the characteristics of the long-range atmospheric spreading of volcanic ash clouds and other pollutants can be investigated in an easy and interactive way. This application is also a suitable tool for studying the chaotic features of the advection and determines two quantities which describe the chaoticity of the advection processes: the stretching rate quantifies the strength of the exponential stretching of pollutant clouds; and the escape rate characterizes the rate of the rapidity by which the settling particles of a pollutant cloud leave the atmosphere.

Beschreibung: The characteristics of the vertical and temporal structure of the coastal atmospheric boundary layer are variable for different sites and are often not well known. Continuous monitoring of the atmospheric boundary layer was carried out close to the Tyrrhenian Sea, near Tarquinia (Italy), in 2015–2017. A ground-based remote sensing instrument (triaxial Doppler sodar) and in situ sensors (meteorological station, ultrasonic anemometer/thermometer, and net radiometer) were used to measure vertical wind velocity profiles, the thermal structure of the atmosphere, the height of the turbulent layer, turbulent heat and momentum fluxes in the surface layer, atmospheric radiation, and precipitation. Diurnal alternation of the atmospheric stability types governed by the solar cycle coupled with local sea/land breeze circulation processes is found to be variable and is classified into several main regimes. Low-level jets (LLJ) at heights of 100–300 m above the surface with maximum wind speed in the range of 5–18 m s−1 occur in land breezes, both during the night and early in the morning. Empirical relationships between the LLJ core wind speed characteristics and those near the surface are obtained. Two separated turbulent sub-layers, both below and above the LLJ core, are often observed, with the upper layer extending up to 400–600 m. Kelvin–Helmholtz billows associated with internal gravity–shear waves occurring in these layers present opposite slopes, in correspondence with the sign of vertical wind speed gradients. Our observational results provide a basis for the further development of theoretical and modelling approaches, taking into account the wave processes occurring in the atmospheric boundary layer at the land–sea interface.

Beschreibung: Studying near-surface aerosol properties is of importance for a better assessment of the aerosol effect on radiative forcing. We employ the data from a near-horizontal lidar to investigate the diurnal behavior of aerosol extinction and single scattering albedo (SSA) at 349 nm. The response of these parameters to ambient relative humidity (RH) is examined for the data from a one-month campaign conducted in Chiba, Japan, during November 2017, a transition period from fall to winter. The Klett method and adaptive slope method are used in deriving the aerosol extinction coefficient from the lidar data, while the SSA values are retrieved using an aethalometer. Also, a visibility-meter is used to examine the aerosol loading inside the atmospheric boundary layer. It is found that the aerosol growth during the deliquescence phase is more readily observed than the contraction in the efflorescence phase. The decrease of SSA before the deliquescence RH is found for approximately 46% of the deliquescence cases, presumably representing the particle shrinkage of soot particles.