Miracle-dz/UniFAR-FTUs huggingface dataset:
Evaluation of two low-cost PM monitors under different laboratory and indoor conditions

Abstract Innovation and technological development have led to a proliferation of various low-cost air quality monitors, most of which use light scattering techniques to detect airborne particles. As these monitors are used in various environments, their testing should also be performed in diverse environments and with different particle types. This study evaluated three Foobot units and three AirVisual Nodes in two laboratory environments and in one residential apartment when measuring five types of aerosols (0.72 and 2.00 µm polystyrene latex (PSL) spheres, Arizona Road Dust (ARD), nanosilver-based surface cleaner, and particles created by a cooking event). The low-cost monitors were highly correlated with the DustTrak DRX (TSI) for most aerosol types (r > 0.78), except when measuring nanosilver spray, where the r value decreased to 0.55. For PSL spheres, Foobot overestimated DRX PM2.5 concentrations while AirVisual's readings were closer to those of DRX and aligned relatively well with the 1:1 line. Both Foobot and AirVisual underestimated PM2.5 concentrations for ARD, nanosilver spray, and particles from a cooking event. Overall, the Foobots reported higher PM2.5 concentrations than the AirVisuals, except when measuring particles created by the cooking event. The paired monitors' precision error varied between 0.15 and 0.47, depending on the aerosol type and monitor pairs. The coefficient of variation ranged from 15.2% to 21.0% for the Foobots and from 12.5% to 28.7% for the AirVisuals. Both monitors showed high accuracy and precision when measuring temperature and humidity as compared to the IAQ Meter (TSI Inc.). AirVisual showed high accuracy and precision when measuring CO2, as compared to the IAQ meter. Foobot, however, didn't report accurate CO2 concentrations. Additionally, we found the AirVisual is easier to operate, and it provided more options to read, save, and download data. Copyright © 2020 American Association for Aerosol Research
The Conformations of Polymethine Dyes

The conformational features of polymethine dyes and related compounds are examined and the principal factors controlled by the conformational equilibrium are identified. The methods for the determination of the geometrical structures of polymethines are discussed. Special attention is devoted to a new method for the determination of their conformations — from the absorption spectra of dyes with two chromophores. The bibliography includes 140 references.
Nucleation and aerosol processing in atmospheric pressure electrical discharges: powders production, coatings and filtration

This review addresses the production of nano-particles and the processing of particles injected in atmospheric pressure electrical discharges (APED). The mechanisms of formation and the evolution of particles suspended in gases are first presented, with numerical and experimental facilities. Different APED and related properties are then introduced for dc corona, streamer and spark filamentary discharges (FD), as well as for ac filamentary and homogeneous dielectric barrier discharges (DBD). Two mechanisms of particle production are depicted in APED: when FD interact with the surface of electrodes or dielectrics and when filamentary and homogeneous DBD induce reactions with gaseous precursors in volume. In both cases, condensable gaseous species are produced, leading to nano-sized particles by physical and chemical routes of nucleation. The evolution of the so-formed nano-particles, i.e. the growth by coagulation/condensation, the charging and the collection are detailed for each APED, with respect to fine powders production and thin films deposition. Finally, when particles are injected in APED, they undergo interfacial processes. Non-thermal plasmas charge particles for electro-collection and trigger heterogeneous chemical reactions for organic and inorganic films deposition. Heat exchanges in thermal plasmas enable powder purification, shaping, melting for hard coatings and fine powders production by reactive evaporation.
Stretched-exponential relaxation of electric birefringence in complex liquids

The relaxation of electric birefringence is experimentally investigated in three distinct systems: critical binary mixtures, polydisperse micellar solutions and dilute polyelectrolyte solutions. The asymptotic behaviour is shown to be consistent with a stretched-exponential form exp(-(t/ tau )alpha ). Most of the data are quantitatively explained by a simple model of parallel relaxation of many independent processes characterized by a wide distribution of sizes.
Comparison of nanofiltration membranes’ performance in flat sheet and spiral wound configurations: a scale-up study

ABSTRACT Nanofiltration (NF) membranes have been largely developed and commercialised over the past decade and are currently one of the most promising technologies for the separation of neutral and charged solutes in aqueous solutions. Sometimes NF is defined as a process between ultrafiltration and reverse osmosis; however, the separation mechanisms of this kind of membranes are not clear enough, and even today there are some questions remaining about how NF membranes work. Nowadays, there are many different types of NF membranes commercially available, so the first step before developing a new NF treatment plant is to know which one is going to be the most suitable membrane. There are two main configurations in which NF can be used: flat sheet and spiral wound module. The cross-flow module using flat sheet membranes is the simplest option to test an NF membrane but at the industrial scale, NF is basically used in the spiral wound configuration. Currently, there are no studies available regarding the dif.
A Study on Enhancement of Fish Recognition Using Cumulative Mean of YOLO Network in Underwater Video Images

In the underwater environment, in order to preserve rare and endangered objects or to eliminate the exotic invasive species that can destroy the ecosystems, it is essential to classify objects and estimate their number. It is very difficult to classify objects and estimate their number. While YOLO shows excellent performance in object recognition, it recognizes objects by processing the images of each frame independently of each other. By accumulating the object classification results from the past frames to the current frame, we propose a method to accurately classify objects, and count their number in sequential video images. This has a high classification probability of 93.94% and 97.06% in the test videos of Bluegill and Largemouth bass, respectively. The proposed method shows very good classification performance in video images taken of the underwater environment.
Experimental investigation of vibration attenuation on a cantilever beam using air-jet pulses with the particle swarm optimized quasi bang–bang controller

This study deals with the vibration reduction of a cantilever beam using air-jet thruster actuators controlled by the particle swarm optimized quasi bang–bang controller. In this study, the finite element model of a cantilever beam with the lumped mass of actuators is formed for the numerical simulations. Furthermore, the first-order plus dead time transfer function of the air-jet thruster actuator is found between the inlet pressure and the thrust. The quasi bang–bang control is proposed to suppress vibrations on the beam with impulsive air-jet pulses. The optimal location of the actuators and control parameters are determined with parametric study and particle swarm optimization, respectively. The performance of the control method is measured with the experiments of initial displacement, the presence of tip masses, and external disturbances. According to all results obtained in this study, it has been observed that the air-jet pulses successfully and rapidly attenuate vibration on the cantilever beam with the quasi bang–bang controller.
Effect of cross‐linking time on the thermal and mechanical properties and pervaporation performance of poly(vinyl alcohol) membrane cross‐linked with fumaric acid used for dehydration of isopropanol

Cross-linked poly (vinyl alcohol) membranes were prepared using fumaric acid as the cross-linking agent and were used for the pervaporation separation of water/isopropanol mixtures. Cross-linking process was carried out at 150°C at three different times of 10, 30, and 60 min. The membranes were characterized by different known methods of FT-IR, TGA, XRD as well as tensile test. The effects of cross-linking time on the thermal and mechanical properties of the membranes and also their pervaporation performance were investigated. Formation of more ester groups by increasing the cross-linking time was confirmed by the FT-IR results. TGA analyses showed that thermal stability of the membranes is improved by prolonging the duration of cross-linking process. This was due to the formation of more compact structure in the membranes. The XRD results revealed that the crystalline regions of the membranes were relatively diminished with an increase in the cross-linking time. No specific trend was observed for the variation of tensile strength at break with the cross-linking time. The PVA membrane cross-linked for 60 min showed high selectivity of 1492 for water permeation for the feed mixture containing 10 wt % water. The temperature dependency of the permeation flux was investigated using Arrhenius relationship, and the activation energy values were calculated for total permeation (Ep), water (Epw), and IPA (EpIPA) fluxes. Lower value of Epw in comparison with EpIPA supported excellent dehydration performance of the cross-linked membranes. Despite large increase in activation energy of water with prolonged cross-linking time, the selectivity was improved. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2013
Formation and dissipation dynamics of the Asian tropopause aerosol layer

The Asian tropopause aerosol layer (ATAL) is characterized by enhanced aerosol concentrations in the Asian summer monsoon anticyclone in the upper troposphere and lower stratosphere at 13–18 km altitude. A growing body of evidence suggests that the aerosol enhancement is closely connected with deep convection during the monsoon. However, the origin of the aerosols is under debate, and the key factors that determine the ATAL variability remain poorly understood. We investigated the formation and dissipation mechanisms of the ATAL and the inter-annual variation from a dynamical viewpoint using satellite observations and meteorological reanalysis data from 2012 to 2018. We identified the northern Bay of Bengal and adjacent land area, where air pollution from the Indian subcontinent converges, as the major convection source area of aerosols to the ATAL. The spatial extent of the ATAL, represented by the mean attenuated scattering ratio from satellite measurements, appears to be related to a secondary circulation driven by the stratospheric quasi-biennial oscillation. The aerosols are not homogeneously distributed within the ATAL, and descending motion in the western part is found to play an important role in dissipation of the layer. These findings elucidate the ATAL dynamics and associated regional and global air pollution transports.
Review on the principle, Progress and Application of Block chain Technology

In recent years, electronic currencies such as bitcoin have been favored by people. As the core technology of Bitcoin, blockchain has attracted the attention of more and more experts and scholars at home and abroad. The changes of its classification mode, service mode and application requirements lead to the diversified development of core technology forms. Blockchain is a distributed ledger technology, which evolves into a complete storage system based on logic control functions such as intelligent contracts. Block chain technology is based on decentralized point-to-point transmission network, using cryptography principles and consensus mechanism to ensure the coherence of each node participating in the distributed system, and to ensure the accuracy, consistency, non-tampering or deletion of the recorded information. All these ensure the establishment of a sharing system with high privacy, high security and high efficiency. In this paper, the basic principles and characteristics of blockchain technology are analyzed, and the research status and application of this technology in the financial system are summarized in detail.
The Influence of Glacial Cover on Riverine Silicon and Iron Exports in Chilean Patagonia

Glaciated environments have been highlighted as important sources of bioavailable nutrients, with inputs of glacial meltwater potentially influencing productivity in downstream ecosystems. However, it is currently unclear how riverine nutrient concentrations vary across a spectrum of glacial cover, making it challenging to accurately predict how terrestrial fluxes will change with continued glacial retreat. Using 40 rivers in Chilean Patagonia as a unique natural laboratory, we investigate how glacial cover affects riverine Si and Fe concentrations, and infer how exports of these bioessential nutrients may change in the future. Dissolved Si (as silicic acid) and soluble Fe (<0.02 μm) concentrations were relatively low in glacier‐fed rivers, whereas concentrations of colloidal‐nanoparticulate (0.02–0.45 μm) Si and Fe increased significantly as a function of glacial cover. These colloidal‐nanoparticulate phases were predominately composed of aluminosilicates and Fe‐oxyhydroxides, highlighting the need for size‐fractionated analyses and further research to quantify the lability of colloidal‐nanoparticulate species. We also demonstrate the importance of reactive particulate (>0.45 μm) phases of both Si and Fe, which are not typically accounted for in terrestrial nutrient budgets but can dominate riverine exports. Dissolved Si and soluble Fe yield estimates showed no trend with glacial cover, suggesting no significant change in total exports with continued glacial retreat. However, yields of colloidal‐nanoparticulate and reactive sediment‐bound Si and Fe were an order of magnitude greater in highly glaciated catchments and showed significant positive correlations with glacial cover. As such, regional‐scale exports of these phases are likely to decrease as glacial cover disappears across Chilean Patagonia, with potential implications for downstream ecosystems.
Cosolvency and sorption of hydrophobic organic chemicals.

Sorption of hydrophobic organic chemicals (HOCs) by two soils was measured from mixed solvents containing water plus completely miscible organic solvents (CMOSs) and partially miscible organic solvents (PMOSs). The utility of the log-linear cosolvency model for predicting HOC sorption from solvent mixtures was evaluated. Co-solvent effects of PMOSs on HOC solubility and sorption were compared. Nonpolar PMOSs (e.g., toluene, p-xylene, and TCE) have low aqueous solubilities and when present either as a cosolvent/cosolute in the aqueous phase or as separate liquid phase do not significantly influence HOC sorption by soils. In contrast, polar PMOSs (e.g., nitrobenzene and o-cresol) have sufficiently high aqueous solubilities that significant decreases in HOC sorption can be measured. The presence of a CMOS increases the PMOS solubility which, in turn, is reflected in increased solubility and decreased sorption of HOCs. Results presented suggest that water-PMOS and sorbent-PMOS interactions need to be considered in predicting the cosolvency of a polar PMOS.
Theoretical Study of the Photophysics of Adenine in Solution: Tautomerism, Deactivation Mechanisms, and Comparison with the 2-Aminopurine Fluorescent Isomer

The lower singlet excited states of isolated and solvated tautomers of adenine and of the fluorescent isomer 2-aminopurine have been studied with different quantum mechanical methods: geometries have been obtained at CIS level, while calculations of electronic structures have been performed using a multireference perturbed CI method and (for excitations) a TDDFT approach. In all calculations, the solvent (e.g., water) has been described within the IEF polarizable continuum model (IEF-PCM). The results have been successfully compared to experimental absorption and emission spectra. The same approach has been applied to the analysis of possible deactivation mechanisms acting on adenine but not on 2-aminopurine: both effects due to the proximity of π → π* and n → π* states and the chance of an intramolecular twisting of the amino group have been considered.
Modified Hydrothermal Route for Synthesis of Photoactive Anatase TiO2/g-CN Nanotubes from Sludge Generated TiO2

Titania nanotube was prepared from sludge generated TiO2 (S-TNT) through a modified hydrothermal route and successfully composited with graphitic carbon nitride (g-CN) through a simple calcination step. Advanced characterization techniques such as X-ray diffraction, scanning and transmission electron microscopy, infrared spectroscopy, X-ray photoelectron spectroscopy, UV/visible diffuse reflectance spectroscopy, and photoluminescence analysis were utilized to characterize the prepared samples. A significant improvement in morphological and optical bandgap was observed. The effective surface area of the prepared composite increased threefold compared with sludge generated TiO2. The optical bandgap was narrowed to 3.00 eV from 3.18 in the pristine sludge generated TiO2 nanotubes. The extent of photoactivity of the prepared composites was investigated through photooxidation of NOx in a continuous flow reactor. Because of extended light absorption of the as-prepared composite, under visible light, 19.62% of NO removal was observed. On the other hand, under UV irradiation, owing to bandgap narrowing, although the light absorption was compromised, the impact on photoactivity was compensated by the increased effective surface area of 153.61 m2/g. Hence, under UV irradiance, the maximum NO removal was attained as 32.44% after 1 h of light irradiation. The proposed facile method in this study for the heterojunction of S-TNT and g-CN could significantly contribute to resource recovery from water treatment plants and photocatalytic atmospheric pollutant removal.
Visual vignettes for cross-national research

ABSTRACT Textual vignettes are a widely popular research tool, but they assume literacy and reading comprehension skills that limit their utility for both research with disadvantaged populations and cross-national research. We describe a new visual vignette approach, based on approaches used in studying populations with lower verbal ability, that avoids the issues raised by live actors while also reducing reliance on written language typical to textual vignettes. We examine the effectiveness of our new visual vignette using a survey experiment in which respondents were exposed to either a visual vignette, or a textual vignette, depicting the same interaction. We found that our visual vignette produced similar results when compared to traditional textual vignettes, confirming their utility. Additionally, we report on a pilot data collection using a cross-national sample, in which English literacy cannot be assumed. Our results indicate that our new method should improve research options both with low literacy populations and foreign language speakers.
Prognostic role of global work index in asymptomatic patients with aortic stenosis

In asymptomatic patients with aortic stenosis (AS), the optimal timing for intervention is still challenging. Previous studies demonstrated that advanced stages of cardiac damage are associated with excess mortality. The role of myocardial work to identify cardiac dysfunction in AS and to predict prognosis has not been investigated. We aimed to evaluate the modification of myocardial work indices related to AS stages and their prognostic value. This study analysed clinical, echocardiographic and outcome data of 170 patients with asymptomatic AS (aortic valve area ≤1.5 cm2) and preserved ejection fraction (LVEF ≥50%). Exclusion criteria were: significant associated cardiac valve lesion, left bundle branch block and suboptimal quality of speckle-tracking image analysis. The control group included 50 patients matched for age and sex. Global work index (GWI), global constructive work (GCW), global wasted work (GWW) and global work efficiency (GWE) were estimated by LV pressure-strain loops. In AS group, LV pressure was evaluated by adding trans-aortic mean gradient to systolic blood pressure. The following staging classification was used: no cardiac damage associated with the valve stenosis (Stage 0), left ventricular damage (Stage 1), left atrial or mitral valve damage (Stage 2), pulmonary hypertension or tricuspid valve damage (Stage 3), or right ventricular damage or subclinical heart failure (Stage 4). While global longitudinal strain was significantly lower in AS than in control group (18.7±2.8 vs 20.7±2.1%, p<0.001), increased values of GCW and GWI (respectively 2948±598 vs 2360±353 mmHg%, and 2528±521 vs 2005±302 mmHg%, p<0.001) were observed in patients with AS. Besides, GWW was significantly increased in AS vs controls (139±90 vs 90±49 mmHg%, p=0.001), with no changes in terms of GWE (95±4 vs 96±2%, p=0.110). When patients were stratified according the stages of cardiac damage, MW indices didn't different significantly, except for the GWI, which was significantly lower in Stage 3 to 4 compared to Stage 0 and Stage 2 (2268±469 vs 2623±503 vs 2610±503 mmHg% respectively, p=0.025). During a mean follow up of 27 months (IQ range 12–48 mo), 18 patients had a CV death. The best GWI value associated with outcome was 1866 mmHg% (sensitivity 45%, specificity 96%, AUC= 0.701, p=0.01). The presence of a GWI at baseline lower than 1866 mmHg% was associated with a higher rate of CV events at 4-year follow-up (57% vs 7%, log-rank p<0.001). On multivariable Cox-regression analysis, BNP values (P=0.014) and GWI <1866 mmHg% (P=0.033) emerged as independently associated with CV death. In asymptomatic patients with AS, advanced stages of cardiac damage are characterized by reduced values of GWI, that are associated with increased mortality. Thus, the evaluation of MW indices may allow a better phenotyping of asymptomatic patients at higher risk of developing cardiovascular events during follow-up. Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Cardiopath PhD program
α,α-Trehalose−Water Solutions. 1. Hydration Phenomena and Anomalies in the Acoustic Properties

The topic dealt with in this paper concerns an experimental study, performed by means of ultrasonic techniques, on aqueous solutions of α,α-trehalose, an effective bioprotector against dehydration. The ultrasonic velocity and density data show that, in these aqueous solutions, the mixing process is not ideal. The behavior of the excess compressibility as a function of concentration can be interpreted by supposing that α,α-trehalose molecules form intramolecular hydrogen bonds by folding over at high concentration. When water molecules are added, they spread out again, thereby releasing hydrogen bond sites for water interactions and increasing the water−sugar interaction strength. Furthermore, the temperature dependence of the hydration number has been evaluated, and its value at room temperature is very close to that given in the literature.