Search results for: temperature and relative humidity

Authors: Zbigniew Szklarz, Aldona Garbacz-Klempka, Magdalena Bisztyga-Szklarz

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Typical metallic alloys bases on one major alloying component, where the addition of other elements is intended to improve or modify certain properties, most of all the mechanical properties. However, in 1995 a new concept of metallic alloys was described and defined. High Entropy Alloys (HEA) contains at least five alloying elements in an amount from 5 to 20 at.%. A common feature this type of alloys is an absence of intermetallic phases, high homogeneity of the microstructure and unique chemical composition, what leads to obtaining materials with very high strength indicators, stable structures (also at high temperatures) and excellent corrosion resistance. Hence, HEA can be successfully used as a substitutes for typical metallic alloys in various applications where a sufficiently high properties are desirable. For fabricating HEA, a few ways are applied: 1/ from liquid phase i.e. casting (usually arc melting); 2/ from solid phase i.e. powder metallurgy (sintering methods preceded by mechanical synthesis) and 3/ from gas phase e.g. sputtering or 4/ other deposition methods like electrodeposition from liquids. Application of different production methods creates different microstructures of HEA, which can entail differences in their properties. The last two methods also allows to obtain coatings with HEA structures, hereinafter referred to as High Entropy Films (HEF). With reference to above, the crucial aim of this work was the optimization of the manufacturing process of the multi-component metallic layers (HEF) by the low- and high temperature electrochemical deposition ( ED). The low-temperature deposition process was crried out at ambient or elevated temperature (up to 100 ᵒC) in organic electrolyte. The high-temperature electrodeposition (several hundred Celcius degrees), in turn, allowed to form the HEF layer by electrochemical reduction of metals from molten salts. The basic chemical composition of the coatings was CoCrFeMnNi (known as Cantor’s alloy). However, it was modified by other, selected elements like Al or Cu. The optimization of the parameters that allow to obtain as far as it possible homogeneous and equimolar composition of HEF is the main result of presented studies. In order to analyse and compare the microstructure, SEM/EBSD, TEM and XRD techniques were employed. Morover, the determination of corrosion resistance of the CoCrFeMnNi(Cu or Al) layers in selected electrolytes (i.e. organic and non-organic liquids) was no less important than the above mentioned objectives.

Keywords: high entropy alloys, electrodeposition, corrosion behavior, microstructure

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Authors: Jungkyun Na, Jaesang Lee, Yang Mo Koo

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In this study to find a replacement for expensive secondary recrystallization in GO electrical steel production, effect of heat treatment on the formation of columnar grain and Goss texture is investigated. The composition of the sample is Fe-2.0Si-0.2C. This process involves repeating of cold rolling and decarburization as a replacement for secondary recrystallization. By cold-rolling shear band is made and Goss grain grows from shear band by decarburization. By doing another cold rolling, some Goss texture is newly formed from the shear band, and some Goss texture is retained in microbands. To determine whether additional heat treatment with H2 atmosphere is needed on decarburization process for growth of Goss texture, comparing between decarburization and heat treatment with H2 atmosphere is performed. Also, to find optimum condition for heat treatment, heat treatment with various time and temperature is performed. It was found that increase in the number of cold rolling and heat treatment increases Goss texture. Both high Goss texture and good columnar structure is achieved at 900℃, and this temperature is within a+r phase region. Heat treatment at a temperature higher than a+r phase region caused carbon diffusion and this made layer with Goss grain decrease.

Keywords: electrical steel, Goss texture, columnar structure, normal grain growth

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Authors: Amjad Abdullah, Amjad Yahya, Bushra Aljohani, Amani Alghamdi

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Change point detection is an important part of data analysis. The presence of a change point refers to a significant change in the behavior of a time series. In this article, we examine the detection of multiple change points of parameters of the exponential Lomax distribution, which is broad and flexible compared with other distributions while fitting data. We used the Schwarz information criterion and binary segmentation to detect multiple change points in publicly available data on the average temperature in the ozone layer. The change points were successfully located.

Keywords: binary segmentation, change point, exponentialLomax distribution, information criterion

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Authors: Meltem Bolluk, Ismail Duman

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Boron exhibits the properties of high melting temperature (2273K to 2573 K), high hardness (Mohs: 9,5), low density (2,340 g/cm3), high chemical resistance, high strength, and semiconductivity (band gap:1,6-2,1 eV). These superior properties enable to use it in several high-tech areas from electronics to nuclear industry and especially in high temperature metallurgy. Amorphous boron and crystalline boron have different application areas. Amorphous boron powder (directly amorphous and/or α-rhombohedral) is preferred in rocket firing, airbag inflating and in fabrication of superconducting MgB2 wires. The conventional ways to produce elemental boron with a purity of 85 pct to 95 prc are metallothermic reduction, fused salt electrolysis and mechanochemical synthesis; but the only way to produce high-purity boron powders is Chemical Vapour Deposition (Hot Surface CVD). In this study; amorphous boron powders with a minimum purity of 99,9 prc were synthesized in quartz tubes using BCl3-H2 gas mixture by CVD. Process conditions based on temperature and gas flow rate were determined. Thermodynamical interpretation of BCl3-H2 system for different temperatures and molar rates were performed using Fact Sage software. The characterization of powders was examined by using Xray diffraction (XRD), Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM), Stereo Microscope (SM), Helium gas pycnometer analysis. The purities of final products were determined by titration after lime fusion.

Keywords: amorphous boron, CVD, powder production, powder characterization

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Authors: Derek Wardle, Tarik Al-Shemmeri, Neil Packer

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This paper presents a small tube/wire type electrostatic precipitator (ESP). In the ESPs present form, particle charging and collecting voltages and airflow rates were individually varied throughout 200 ambient temperature test runs ranging from 10 to 30 kV in increments on 5 kV and 0.5 m/s to 1.5 m/s, respectively. It was repeatedly observed that, at input air velocities of between 0.5 and 0.9 m/s and voltage settings of 20 kV to 30 kV, the collection efficiency remained above 95%. The outcomes of preliminary tests at combustion flue temperatures are, at present, inconclusive although indications are that there is little or no drop in comparable performance during ideal test conditions. A limited set of similar tests was carried out during which the collecting electrode was grounded, having been disconnected from the static generator. The collecting efficiency fell significantly, and for that reason, this approach was not pursued further. The collecting efficiencies during ambient temperature tests were determined by mass balance between incoming and outgoing dry PM. The efficiencies of combustion temperature runs are determined by analysing the difference in opacity of the flue gas at inlet and outlet compared to a reference light source. In addition, an array of Leit tabs (carbon coated, electrically conductive adhesive discs) was placed at inlet and outlet for a number of four-day continuous ambient temperature runs. Analysis of the discs’ contamination was carried out using scanning electron microscopy and ImageJ computer software that confirmed collection efficiencies of over 99% which gave unequivocal support to all the previous tests. The average efficiency for these runs was 99.409%. Emissions collected from a woody biomass combustion unit, classified to a diameter of 100 µm, were used in all ambient temperature trials test runs apart from two which collected airborne dust from within the laboratory. Sawdust and wood pellets were chosen for laboratory and field combustion trials. Video recordings were made of three ambient temperature test runs in which the smoke from a wood smoke generator was drawn through the precipitator. Although these runs were visual indicators only, with no objective other than to display, they provided a strong argument for the device’s claimed efficiency, as no emissions were visible at exit when energised.  The theoretical performance of ESPs, when applied to the geometry and configuration of the tested model, was compared to the actual performance and was shown to be in good agreement with it.

Keywords: electrostatic precipitators, air quality, particulates emissions, electron microscopy, image j

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Authors: P. N. Okeke, J. N. Chikwendu

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The study evaluated the effects of varying fermentation periods on the nutrients and anti-nutrients composition of African yam bean (Sphenostylis stenocarpa) and acha (Digitaria exilis) flour blends and sensory properties of their products. The African yam bean seeds and acha grains were fermented for 24 hrs, 48 and 72 hrs, dried (sun drying) and milled into fine flour. The fermented flours were used in a ratio of 70:30 (Protein basis) to formulate composite flour for meat pie and biscuits production. Both the fermented and unfermented flours and products were analyzed for chemical composition using the standard method. The data were statistically analyzed using SPSS version 15 to determine the mean and standard deviation. The 24, 48, and 72 hrs fermentation periods increased protein (22.81, 26.15 and 24.00% respectively). The carbohydrate, ash and moisture contents of the flours were also increased as a result of fermentation (68.01-76.83, 2.26-4.88, and 8.36-13.00% respectively). The 48 hrs fermented flour blends had the highest increase in ash relative to the control (4.88%). Fermentation increased zinc, iron, magnesium and phosphorus content of the flours. Treatment drastically reduced the anti-nutrient (oxalate, saponin, tannin, phytate, and hemagglutinin) levels of the flours. Both meat pie and biscuits had increased protein relative to the control (27.36-34.28% and 23.66-25.09%). However, the protein content of the meat pie increased more than that of the biscuits. Zinc, Iron, Magnesium and phosphorus levels increased in both meat pie and biscuits. Organoleptic attributes of the products (meat pie and biscuits) were slightly lower than the control except those of the 72 hrs fermented flours.

Keywords: fermentation, African yam bean, acha, biscuits, meat-pie

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Authors: Shaeel A. Al Thabaiti, Sulaiman N. Basahel, Salem M. Bawaked, Mohamed Mokhtar

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Nanosheets for cobalt-layered double hydroxide (Co-Al-LDH)/GO were successfully synthesized with different Co:M g:Al ratios (0:3:1, 1.5:1.5:1, and 3:0:1). The layered double hydroxide structure and morphology were determined using x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Temperature prgrammed reduction (TPR) of Co-Al-LDH showed reduction peaks at lower temperature which indicates the ease reducibility of this particular sample. The thermal behaviour was studied using thermal graviemetric technique (TG), and the BET-surface area was determined using N2 physisorption at -196°C. The C-C coupling reaction was carried out over all the investigated catalysts. The Mg–Al LDH catalyst without Co ions is inactive, but the isomorphic substitution of Mg by Co ions (Co:Mg:Al = 1.5:1.5:1) in the cationic sheet resulted in 88% conversion of iodobenzene under reflux. LDH/GO hybrid is up to 2 times higher activity than for the unsupported LDH.

Keywords: adsorption, co-precipitation, graphene oxide, layer double hydroxide

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Authors: Carlos A. Acosta, Amar Bhalla, Ruyan Guo

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Scraped surface heat exchangers (SSHE) use a rotor shaft assembly with scraping blades to homogenize viscous fluids during the heat transfer process. Obtaining in-situ measurements is difficult because the rotor and scraping blades spin continuously inside the mixing chamber, obstructing the instrumentation pathway. Computational fluid dynamics simulations provide useful insight into the flow behavior around the scraper blades for a variety of fluids and blade geometries. However, numerical solutions often focus on the fluid dynamics and heat transfer phenomena of rotating flow, ignoring the glass-transition temperature and freezing point depression. This research studies the multi-phase fluid dynamics and freezing point depression inside the SSHE with non-isothermal conditions in a time dependent process using an aqueous solution that contains 13.5 wt.% high fructose corn syrup and CO₂. The computational results were validated with in-situ pressure, temperature, and optical spectroscopy measurements. Results from the numerical model show good quantitatively agreement with experimental values.

Keywords: computational fluid dynamics, freezing point depression, phase-transition temperature, multi-phase flow

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Authors: Marutani M, Kawajiri H, Usui C, Takai Y, Kawaguchi T

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Background: To build the inclusive society, the Japanese government provides “transition support for employment system” for Persons with Disabilities (PWDs). It is, however, difficult to provide appropriate accommodations due to their changeable health conditions. Mobile phone applications (App) are useful to monitor their health conditions and their environments, and effective to improve reasonable accommodations for PWDs. Purpose: This study aimed to develop an App that PWDs input their self-assessment and make their health conditions and environment conditions visible. To attain the goal, we investigated the items of the App for the first step. Methods: Qualitative and descriptive design was used for this study. Study participants were recruited by snowball sampling in July and August 2023. They had to have had minimum of five-years of experience to support PWDs’ employment. Semi-structured interviews were conducted on their assessment regarding PWDs’ conditions of daily activities, their health conditions, and living and working environment. Verbatim transcript was created from each interview content. We extracted the following items in tree groups from each verbatim transcript: daily activities, health conditions, and living and working. Results: Fourteen participants were involved (average years of experience: 10.6 years). Based on the interviews, tree item groups were enriched. The items of daily activities were divided into fifty-five. The example items were as follows: “have meals on one’s style” “feel like slept well” “wake-up time, bedtime, and mealtime are usually fixed.” “commute to the office and work without barriers.” Thirteen items of health conditions were obtained like “feel no anxiety” “relieve stress” “focus on work and training” “have no pain” “have the physical strength to work for one day.” The items of categories of living and working environments were divided into fifteen-two. The example items were as follows: “have no barrier in home” “have supportive family members” “have time to take medication on time while at work” “commute time is just right” “people at the work understand the symptoms” “room temperature and humidity are just right” “get along well with friends in my own way.” The participants also mentioned the styles to input self-assessment like that a face scale would be preferred to number scale. Conclusion: The items were enriched existent paper-based assessment items in terms of living and working environment because those were obtained from the perspective of PWDs. We have to create the app and examine its usefulness with PWDs toward inclusive society.

Keywords: occupational health, innovatiove tool, people with disability, employment

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Authors: Caixia Gao, Chuanrong Li, Lingli Tang, Lingling Ma, Yonggang Qian, Ning Wang

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Knowledge of land surface temperature (LST) is of crucial important in energy balance studies and environment modeling. Satellite thermal infrared (TIR) imagery is the primary source for retrieving LST at the regional and global scales. Due to the combination of atmosphere and land surface of received radiance by TIR sensors, atmospheric effect correction has to be performed to remove the atmospheric transmittance and upwelling radiance. Spinning Enhanced Visible and Infrared Imager (SEVIRI) onboard Meteosat Second Generation (MSG) provides measurements every 15 minutes in 12 spectral channels covering from visible to infrared spectrum at fixed view angles with 3km pixel size at nadir, offering new and unique capabilities for LST, LSE measurements. However, due to its high temporal resolution, the atmosphere correction could not be performed with radiosonde profiles or reanalysis data since these profiles are not available at all SEVIRI TIR image acquisition times. To solve this problem, a two-part six-parameter semi-empirical diurnal temperature cycle (DTC) model has been applied to the temporal interpolation of ECMWF reanalysis data. Due to the fact that the DTC model is underdetermined with ECMWF data at four synoptic times (UTC times: 00:00, 06:00, 12:00, 18:00) in one day for each location, some approaches are adopted in this study. It is well known that the atmospheric transmittance and upwelling radiance has a relationship with water vapour content (WVC). With the aid of simulated data, the relationship could be determined under each viewing zenith angle for each SEVIRI TIR channel. Thus, the atmospheric transmittance and upwelling radiance are preliminary removed with the aid of instantaneous WVC, which is retrieved from the brightness temperature in the SEVIRI channels 5, 9 and 10, and a group of the brightness temperatures for surface leaving radiance (Tg) are acquired. Subsequently, a group of the six parameters of the DTC model is fitted with these Tg by a Levenberg-Marquardt least squares algorithm (denoted as DTC model 1). Although the retrieval error of WVC and the approximate relationships between WVC and atmospheric parameters would induce some uncertainties, this would not significantly affect the determination of the three parameters, td, ts and β (β is the angular frequency, td is the time where the Tg reaches its maximum, ts is the starting time of attenuation) in DTC model. Furthermore, due to the large fluctuation in temperature and the inaccuracy of the DTC model around sunrise, SEVIRI measurements from two hours before sunrise to two hours after sunrise are excluded. With the knowledge of td , ts, and β, a new DTC model (denoted as DTC model 2) is accurately fitted again with these Tg at UTC times: 05:57, 11:57, 17:57 and 23:57, which is atmospherically corrected with ECMWF data. And then a new group of the six parameters of the DTC model is generated and subsequently, the Tg at any given times are acquired. Finally, this method is applied to SEVIRI data in channel 9 successfully. The result shows that the proposed method could be performed reasonably without assumption and the Tg derived with the improved method is much more consistent with that from radiosonde measurements.

Keywords: atmosphere correction, diurnal temperature cycle model, land surface temperature, SEVIRI

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Authors: Othman Saoudi

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In this work, we have interested in the investigation of the chemical denaturants and synthesized ionic liquids effects on the fluorescence properties of the laccase from Trametes versicolor. The fluorescence properties of the laccase result from the presence of Tryptophan, which has an aromatic core responsible for the absorption in ultra violet domain and the emission of the photons of fluorescence. The effect Pyrrolidinuim Formate ([pyrr][F]) and Morpholinium Formate ([morph][F]) ionic liquids on the laccase behavior for various volumetric fractions are studied. We have shown that the fluorescence spectrum relative to the [pyrr][F] presents a single band with a maximum around 340 nm and a secondary peak at 361 nm for a volumetric fraction of 20% v/v. For concentration superiors to 40%, the fluorescence intensity decreases and a displacement of the peaks toward higher wavelengths has occurred. For the [morph][F], the fluorescence spectrum showed a single band around 340 nm. The intensity of the principal peak decreases for concentration superiors to 20% v/v. From the plot representing the variation of the λₘₐₓ versus the volumetric concentration, we have determined the concentration of the half-transitions C1/2. These concentrations are equal to 42.62% and 40.91% v/v in the presence of [pyrr][F] and [morph][F] respectively. For the chemical denaturation, we have shown that the fluorescence intensity decreases with increasing denaturant concentrations where the maximum of the wavelength of emission shifts toward the higher wavelengths. We have also determined from the spectrum relative to the urea and GdmCl, the unfolding energy, ∆GD. The results show that the variation of the unfolding energy as a function of the denaturant concentrations varies according to the linear regression model. We have demonstrated also that the half-transitions C1/2 have occurred for urea and GdmCl denaturants concentrations around 3.06 and 3.17 M respectively.

Keywords: laccase, fluorescence, ionic liquids, chemical denaturants

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Authors: Noriyuki Suyama

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This paper discusses purchasing behavior in retail stores, with a particular focus on the impact of weather changes on customers' purchasing behavior. Weather conditions are one of the factors that greatly affect the management and operation of retail stores. However, there is very little research on the relationship between weather conditions and marketing from an academic perspective, although there is some importance from a practical standpoint and knowledge based on experience. For example, customers are more hesitant to go out when it rains than when it is sunny, and they may postpone purchases or buy only the minimum necessary items even if they do go out. It is not difficult to imagine that weather has a significant impact on consumer behavior. To the best of the authors' knowledge, there have been only a few studies that have delved into the purchasing behavior of individual customers. According to Hirata (2018), the economic impact of weather in the United States is estimated to be 3.4% of GDP, or "$485 billion ± $240 billion per year. However, weather data is not yet fully utilized. Representative industries include transportation-related industries (e.g., airlines, shipping, roads, railroads), leisure-related industries (e.g., leisure facilities, event organizers), energy and infrastructure-related industries (e.g., construction, factories, electricity and gas), agriculture-related industries (e.g., agricultural organizations, producers), and retail-related industries (e.g., retail, food service, convenience stores, etc.). This paper focuses on the retail industry and advances research on weather. The first reason is that, as far as the author has investigated the retail industry, only grocery retailers use temperature, rainfall, wind, weather, and humidity as parameters for their products, and there are very few examples of academic use in other retail industries. Second, according to NBL's "Toward Data Utilization Starting from Consumer Contact Points in the Retail Industry," labor productivity in the retail industry is very low compared to other industries. According to Hirata (2018) mentioned above, improving labor productivity in the retail industry is recognized as a major challenge. On the other hand, according to the "Survey and Research on Measurement Methods for Information Distribution and Accumulation (2013)" by the Ministry of Internal Affairs and Communications, the amount of data accumulated by each industry is extremely large in the retail industry, so new applications are expected by analyzing these data together with weather data. Third, there is currently a wealth of weather-related information available. There are, for example, companies such as WeatherNews, Inc. that make weather information their business and not only disseminate weather information but also disseminate information that supports businesses in various industries. Despite the wide range of influences that weather has on business, the impact of weather has not been a subject of research in the retail industry, where business models need to be imagined, especially from a micro perspective. In this paper, the author discuss the important aspects of the impact of weather on marketing strategies in the non-food retail industry.

Keywords: consumer behavior, weather marketing, marketing science, big data, retail marketing

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Authors: Majid Javanmard

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In this study, the effects of coating with whey protein concentrate (7.5% w/v) alone and/or in combination with rice bran oil (0.2, 0.4, 0.6 g in 100 ml coating solution) and Zataria multiflora extract (1 and 2 μL in 100 ml coating solution) on the quality attributes and egg shelf life were carefully observed and analyzed. Weight loss, Haugh index, yolk index, pH, air cell depth, shell strength and the impact of this coating on the microbial load of the eggs surface were studied at the end of each week (during the 4 weeks of storage in a room environment temperature and humidity). After 4 weeks of storage, it was observed that the weight loss in all of the treated eggs with whey protein concentrate and 0.2 gr of rice bran oil (experimental group) was significantly lower than that of the control group(P < 0/05). With regard to Haugh index and yolk index, egg shelf life increased about 4 weeks compared with the control samples. Haugh Index changes revealed that the coated samples remained at grade A after 3 weeks of storage, while the control samples were relegated from grade AA to B after one week. Haugh and yolk Indices in all coated eggs were more than those of the control group. In the coated groups, Haugh and yolk indices of the coated samples with whey protein concentrate and 0.2 g rice bran oil and with whey protein concentrate and 0.2g of rice bran oil and 1 micro liter of Zataria multiflora extract were more than those of the other coated eggs and the control group eggs. PH values of the control group were higher than those of the coated groups during the storage of the eggs. The shell strength of the coated group was more than that of the control group (uncoated) and in coated samples, whey protein concentrate and 0.2 gr of rice bran oil coated samples had high shell strength. In the other treatments, no significant differences were observed. The depth of the air cell of the coated groups was determined to be less than that of the control group during the storage period. The minimum inhibitory concentration was 1 μL of Zataria multiflora extract. The results showed that 1 μL concentration of Zataria multiflora extract reduces the microbial load of the egg shell surface to 87% and 2 μL reduced total bacterial load to zero. In sensory evaluation, from evaluator point of view, the coated eggs had more overall acceptance than the uncoated group (control), and in the treatment group coated eggs, those containing a low percentage of rice bran oil had higher overall acceptability. In conclusion, coating as a practical and cost effective method can maintain the quality parameters of eggs and lead to durability of supply conditions in addition to the product marketability.

Keywords: edible coating, chicken egg, whey protein concentrate, rice bran oil, Zataria multiflora extract, shelf life

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Authors: I. Siti Rabiatull Aisha, A. Ourdjini, O. Saliza Azlina

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The aim of this paper is to study the effectiveness of bismuth addition in the solder alloy to retard the intermetallic compound formation and growth. In this study, three categories of solders such as Sn-4Ag-xCu (x = 0.5, 0.7, 1.0) and Sn-4Ag-0.5Cu-xBi (x = 0.1, 0.2, 0.4) were used. Ni/Au surface finish substrates were dipped into the molten solder at a temperature of 180-190 ^oC and allowed to cool at room temperature. The intermetallic compound (IMCs) were subjected to the characterization in terms of composition and morphology. The IMC phases were identified by energy dispersive x-ray (EDX), whereas the optical microscope and scanning electron microscopy (SEM) were used to observe microstructure evolution of the solder joint. The results clearly showed that copper concentration dependency was high during the reflow stage. Besides, only Ni₃Sn₄ and Ni₃Sn₂ were detected for all copper concentrations. The addition of Bi was found to have no significant effect on the type of IMCs formed, but yet the grain became further refined.

Keywords: Bismuth addition, intermetallic compound, composition, morphology

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Authors: Zhao Bo

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The TiO2-Na2SO3 and SiO2-Na2SO3 nano-fluids were prepared using ultrasonic dispertion method without any surfactant addition to study the influence of nano-fluids on the mass transfer during forced sulfite oxidation in a thermostatic stirred tank, and the kinetic viscosity of nano-fluids was measured. The influence of temperature (30 ℃ ~ 50 ℃), solid loading of fine particle (0 Kg/m³~1.0 Kg/m³), stirring speed (50 r/min ~ 400 r/min), and particle size (10 nm~100 nm) on the average oxygen absorption rate were investigated in detail. Both TiO2 nano-particles and SiO2 nano-particles could remarkably improve the gas-liquid mass transfer. Oxygen absorption enhancement factor increases with the increase of solid loading of nano-particles to a critical value and then decreases with further increase of solid loading under 30℃. Oxygen absorption rate together with absorption enhancement factor increases with stirring speed. However, oxygen absorption enhancement factor decreases with the increase of temperature due to aggregation of nano-particles. Further inherent relationship between particle size, loading, surface area, viscosity, stirring speed, temperature, adsorption, desorption, and mass transfer was discussed in depth by analyzing the interaction mechanism.

Keywords: fine particles, nano-fluid, mass transfer enhancement, solid loading

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Authors: M. Bahgat, F. M. Awan, H. A. Hanafy, O. N. Alzeghaibi

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Strontium hexaferrite (SrFe12O19; Sr-ferrite) is one of the well-known materials for permanent magnets. In this study, M-type strontium ferrite was prepared by following the conventional ceramic method from steelmaking by-product. Initial materials; SrCO3 and by-product, were mixed together in the composition of SrFe12O19 in different Sr/Fe ratios. The mixtures of these raw materials were dry-milled for 6h. The blended powder was pre-sintered (i.e. calcination) at 1000°C for different times periods, then cooled down to room temperature. These pre-sintered samples were re-milled in a dry atmosphere for 1h and then fired at different temperatures in atmospheric conditions, and cooled down to room temperature. The produced magnetic powder has a dense hexagonal grain shape structure. The calculated energy product values for the produced samples ranged from 0.3 to 2.4 MGOe.

Keywords: hard magnetic materials, ceramic route, strontium ferrite, synthesis

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Authors: Asnakew Mulualem Tegegne, Tarun Kumar Lohani, , Abunu Atlabachew Eshete

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Groundwater quality has become deteriorated due to natural and anthropogenic activities. Poor water quality has a potential risk to human health and the environment. Therefore, the study aimed to assess the potential risk of groundwater quality contamination levels and public health risks in the Gunabay watershed. For this task, seventy-eight groundwater samples were collected from thirty-nine locations in the dry and wet seasons during 2022. The ground water contamination index was applied to assess the overall quality of groundwater. Six major driving forces (temperature, population density, soil, land cover, recharge, and geology) and their quantitative impact of each factor on groundwater quality deterioration were demonstrated using Geodetector. The results showed that low groundwater quality was detected in urban and agricultural land. Especially nitrate contamination was highly linked to groundwater quality deterioration and public health risks, and a medium contamination level was observed in the area. This indicates that the inappropriate application of fertilizer on agricultural land and wastewater from urban areas has a great impact on shallow aquifers in the study area. Furthermore, the major influencing factors are ranked as soil type (0.33–0.31)>recharge (0.17–0.15)>temperature (0.13–0.08)>population density (0.1–0.08)>land cover types (0.07– 0.04)>lithology (0.05–0.04). The interaction detector revealed that the interaction between soil ∩ recharge, soil ∩ temperature, and soil ∩ land cover, temperature ∩ recharge is more influential to deteriorate groundwater quality in both seasons. Identification and quantification of the major influencing factors may provide new insight into groundwater resource management.

Keywords: groundwater contamination index, geographical detectors, public health · influencing factors, and water resources management

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Authors: Donald G. Danmeier, Gian Marco Pizzo, Matthew Brennan

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Although wetlands have been proposed as a green alternative to manage coastal flood hazards because of their capacity to adapt to sea level rise and provision of multiple ecological and social co-benefits, they are often overlooked due to challenges in quantifying the uncertainty and naturally, variability of these systems. This objective of this study was to quantify wave attenuation provided by a natural marsh surrounding a large oil refinery along the US Gulf Coast that has experienced steady erosion along the shoreward edge. The vegetation module of the SWAN was activated and coupled with a hydrodynamic model (DELFT3D) to capture two-way interactions between the changing water level and wavefield over the course of a storm event. Since the marsh response to relative sea level rise is difficult to predict, a range of future marsh morphologies is explored. Numerical results were examined to determine the amount of wave attenuation as a function of marsh extent and the relative contributions from white-capping, depth-limited wave breaking, bottom friction, and flexing of vegetation. In addition to the coupled DELFT3D-SWAN modeling of a storm event, an uncoupled SWAN-VEG model was applied to a simplified bathymetry to explore a larger experimental design space. The wave modeling revealed that the rate of wave attenuation reduces for higher surge but was still significant over a wide range of water levels and outboard wave heights. The results also provide insights to the minimum marsh extent required to fully realize the potential wave attenuation so the changing coastal hazards can be managed.

Keywords: green infrastructure, wave attenuation, wave modeling, wetland

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Authors: Terryann Clark, Kabir Dasgupta, Sonia Lewycka, Gail Pacheco, Alexander Plum

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This paper focused on two main research aims using data from the Growing Up in New Zealand (GUINZ) birth cohort: 1. To examine ethnic differences in life-course trajectories in the use and experience of healthcare services in early childhood years (namely immunisation, dental checks and use of General Practitioners (GPs)) 2. To quantify the contribution of relevant explanatory factors to ethnic differences. Current policy in New Zealand indicates there should be, in terms of associated direct costs, equitable access by ethnicity for healthcare services. However, empirical evidence points to persistent ethnic gaps in several domains. For example, the data highlighted that Māori have the lowest immunisation rates, across a number of time points in early childhood – despite having a higher antenatal intention to immunise relative to NZ European. Further to that, NZ European are much more likely to have their first-choice lead maternity caregiver (LMC) and use child dental services compared to all ethnicities. Method: This research explored the underlying mechanisms behind ethnic differences in the use and experience of child healthcare services. First, a multivariate regression analysis was used to adjust raw ethnic gaps in child health care utilisation by relevant covariates. This included a range of factors, encompassing mobility, socio-economic status, mother and child characteristics, household characteristics and other social aspects. Second, a decomposition analysis was used to assess the proportion of each ethnic gap that can be explained, as well as the main drivers behind the explained component. The analysis for both econometric approaches was repeated for each data time point available, which included antenatal, 9 months, 2 years and 4 years post-birth. Results: The following findings emerged: There is consistent evidence that Asian and Pacific peoples have a higher likelihood of child immunisation relative to NZ Europeans and Māori. This was evident at all time points except one. Pacific peoples had a lower rate relative to NZ European for receiving all first-year immunisations on time. For a number of potential individual and household predictors of healthcare service utilisation, the association is time-variant across early childhood. For example, socio-economic status appears highly relevant for timely immunisations in a child’s first year, but is then insignificant for the 15 month immunisations and those at age 4. Social factors play a key role. This included discouragement or encouragement regarding child immunisation. When broken down by source, discouragement by family has the largest marginal effect, followed by health professionals; whereas for encouragement, medical professionals have the largest positive influence. Perceived ethnically motivated discrimination by a health professional was significant with respect to both reducing the likelihood of achieving first choice LMC, and also satisfaction levels with child’s GP. Some ethnic gaps were largely unexplained, despite the wealth of factors employed as independent variables in our analysis. This included understanding why Pacific mothers are much less likely to achieve their first choice LMC compared to NZ Europeans; and also the ethnic gaps for both Māori and Pacific peoples relative to NZ Europeans concerning dental service use.

Keywords: child health, cohort analysis, ethnic disparities, primary healthcare

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Authors: Bal Chandra Yadav, Rakesh K. Sonker, Anjali Sharma, Punit Tyagi, Vinay Gupta, Monika Tomar

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In the present study, ZnO doped SnO2 thin films of various compositions were deposited on the surface of a corning substrate by dropping the two sols containing the precursors for composite (ZSO) with subsequent heat treatment. The sensor materials used for selective detection of nitrogen dioxide (NO2) were designed from the correlation between the sensor composition and gas response. The available NO2 sensors are operative at very high temperature (150-800 °C) with low sensing response (2-100) even in higher concentrations. Efforts are continuing towards the development of NO2 gas sensor aiming with an enhanced response along with a reduction in operating temperature by incorporating some catalysts or dopants. Thus in this work, a novel sensor structure based on ZSO nanocomposite has been fabricated using chemical route for the detection of NO2 gas. The structural, surface morphological and optical properties of prepared films have been studied by using X-ray diffraction (XRD), Atomic force microscopy (AFM), Transmission electron microscope (TEM) and UV-visible spectroscopy respectively. The effect of thickness variation from 230 nm to 644 nm of ZSO composite thin film has been studied and the ZSO thin film of thickness ~ 460 nm was found to exhibit the maximum gas sensing response ~ 2.1×103 towards 20 ppm NO2 gas at an operating temperature of 90 °C. The average response and recovery times of the sensor were observed to be 3.51 and 6.91 min respectively. Selectivity of the sensor was checked with the cross-exposure of vapour CO, acetone, IPA, CH4, NH3 and CO2 gases. It was found that besides the higher sensing response towards NO2 gas, the prepared ZSO thin film was also highly selective towards NO2 gas.

Keywords: ZSO nanocomposite thin film, ZnO tetrapod structure, NO2 gas sensor, sol-gel method

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Authors: Tania Bose, Minto Rattan, Neeraj Chamoli

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In this paper, an attempt has been made to study the effect of thermal gradation on the steady-state creep behavior of rotating isotropic disc made of functionally graded material using threshold stress based Sherby’s creep law. The composite discs made of aluminum matrix reinforced with silicon carbide particulate have been taken for analysis. The stress and strain rate distributions have been calculated for the discs rotating at elevated temperatures having thermal gradation. The material parameters of creep vary radially and have been estimated by regression fit of the available experimental data. Investigations for discs made up of linearly increasing particle content operating under linearly decreasing temperature from inner to outer radii have been done using von Mises’ yield criterion. The results are displayed and compared graphically in designer friendly format for the above said disc profile with the disc made of particle reinforced composite operating under uniform temperature profile. It is observed that radial and tangential stresses show minor variation and the strain rates vary significantly in the presence of thermal gradation as compared to disc having uniform temperature.

Keywords: creep, isotropic, steady-state, thermal gradation

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Authors: M. Meenasaranya, S. Saravanan

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Nonlinear stability analysis is carried out to determine the effect of surface temperature modulation in an infinite horizontal porous layer heated from below. The layer is saturated by an electrically conducting, viscous, incompressible and Newtonian fluid. The Brinkman model is used for momentum equation, and the Boussinesq approximation is invoked. The system is assumed to be bounded by rigid boundaries. The energy theory is implemented to find the global exponential stability region of the considered system. The results are analysed for arbitrary values of modulation frequency and amplitude. The existence of subcritical instability region is confirmed by comparing the obtained result with the known linear result. The vertical magnetic field is found to stabilize the system.

Keywords: Brinkman model, energy method, magnetic field, surface temperature modulation

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Authors: Hyun Chul Cho, Hyunkyoung Oh, Hyun Yoon, Jooyeon Jin, Jae Won Lee

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Identifying, structuring, and racking the most important factors related to improving athletes’ performances could pave the way for improve training system. The purpose of this study was to identify the relative importance factors to improve performance of the of judo athletes with visual impairments, including blindness by using the Analytic Hierarchy Process (AHP). After reviewing the literature, the relative importance of factors affecting performance of the blind judo was selected. A group of expert reviewed the first draft of the questionnaires, and then finally selected performance factors were classified into the major categories of techniques, physical fitness, and psychological categories. Later, a pre-selected experts group was asked to review the final version of questionnaire and confirm the priories of performance factors. The order of priority was determined by performing pairwise comparisons using Expert Choice 2000. Results indicated that “grappling” (.303) and “throwing” (.234) were the most important lower hierarchy factors for blind judo skills. In addition, the most important physical factors affecting performance were “muscular strength and endurance” (.238). Further, among other psychological factors “competitive anxiety” (.393) was important factor that affects performance. It is important to offer psychological skills training to reduce anxiety of judo athletes with visual impairments and blindness, so they can compete in their optimal states. These findings offer insights into what should be considered when determining factors to improve performance of judo athletes with visual impairments and blindness.

Keywords: analytic hierarchy process, blind athlete, judo, sport performance

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Authors: Pantana Tor-Ngern

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In the global water cycle, tree water use (Tr) largely contributes to evapotranspiration which is the total amount of water evaporated from terrestrial ecosystems to the atmosphere, regulating climates. Tree water use responds to environmental factors, including atmospheric humidity and sunlight (represented by vapor pressure deficit or VPD and photosynthetically active radiation or PAR, respectively) and soil moisture. In forests, Tr responses to such factors depend on species and their spatial and temporal variations. Tropical forests in Southeast Asia (SEA) have experienced land-use conversion from abandoned agricultural practices, resulting in patches of forests at different stages including old-growth and secondary forests. Because the inherent structures, such as canopy height and tree density, significantly vary among forests at different stages and can strongly affect their respective microclimate, Tr and its responses to changing environmental conditions in successional forests may differ. Daily and seasonal variations in the environmental factors may exert significant impacts on the respective Tr patterns. Extrapolating Tr data from short periods of days to longer periods of seasons or years can be complex and is important for estimating long-term ecosystem water use which often includes normal and abnormal climatic conditions. Thus, this study aims to investigate the diurnal variation of Tr, using measured sap flux density (JS) data, with changes in VPD in eight evergreen tree species in an old-growth forest (hereafter OF; >200 years old) and a young forest (hereafter YF, <10 years old) in Khao Yai National Park, Thailand. The studied species included Sysygium syzygoides, Aquilaria crassna, Cinnamomum subavenium, Nephelium melliferum, Altingia excelsa in OF, and Syzygium nervosum and Adinandra integerrima in YF. Only Sysygium antisepticum was found in both forest stages. Specifically, hysteresis, which indicates the asymmetrical changes of JS in response to changing VPD across daily timescale, was examined in these species. Results showed no hysteresis in all species in OF, except Altingia excelsa which exhibited a 3-hour delayed JS response to VPD. In contrast, JS of all species in YF displayed one-hour delayed responses to VPD. The OF species that showed no hysteresis indicated their well-coupling of their canopies with the atmosphere, facilitating the gas exchange which is essential for tree growth. The delayed responses in Altingia excelsa in OF and all species in YF were associated with higher JS in the morning than that in the afternoon. This implies that these species were sensitive to drying air, closing stomata relatively rapidly compared to the decreasing atmospheric humidity (VPD). Such behavior is often observed in trees growing in dry environments. This study suggests that detailed investigation of JS at sub-daily timescales is imperative for better understanding of mechanistic responses of trees to the changing climate, which will benefit the improvement of earth system models.

Keywords: sap flow, tropical forest, forest succession, thermal dissipcation probe

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Authors: Sulalit Bandyopadhyay, Muhammad Awais Ashfaq Alvi, Anuvansh Sharma, Wilhelm R. Glomm

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Release of drugs from nanogels and nanogel-based systems can occur under the influence of external stimuli like temperature, pH, magnetic fields and so on. pNIPAm-AAc nanogels respond to the combined action of both temperature and pH, the former being mostly determined by hydrophilic-to-hydrophobic transitions above the volume phase transition temperature (VPTT), while the latter is controlled by the degree of protonation of the carboxylic acid groups. These nanogels based systems are promising candidates in the field of drug delivery. Combining nanogels with magneto-plasmonic nanoparticles (NPs) introduce imaging and targeting modalities along with stimuli-response in one hybrid system, thereby incorporating multifunctionality. Fe@Au core-shell NPs possess optical signature in the visible spectrum owing to localized surface plasmon resonance (LSPR) of the Au shell, and superparamagnetic properties stemming from the Fe core. Although there exist several synthesis methods to control the size and physico-chemical properties of pNIPAm-AAc nanogels, yet, there is no comprehensive study that highlights the dependence of incorporation of one or more layers of NPs to these nanogels. In addition, effective determination of volume phase transition temperature (VPTT) of the nanogels is a challenge which complicates their uses in biological applications. Here, we have modified the swelling-collapse properties of pNIPAm-AAc nanogels, by combining with Fe@Au NPs using different solution based methods. The hydrophilic-hydrophobic transition of the nanogels above the VPTT has been confirmed to be reversible. Further, an analytical method has been developed to deduce the average VPTT which is found to be 37.3°C for the nanogels and 39.3°C for nanogel coated Fe@Au NPs. An opposite swelling –collapse behaviour is observed for the latter where the Fe@Au NPs act as bridge molecules pulling together the gelling units. Thereafter, Cyt C, a model protein drug and L-Dopa, a drug used in the clinical treatment of Parkinson’s disease were loaded separately into the nanogels and nanogel coated Fe@Au NPs, using a modified breathing-in mechanism. This gave high loading and encapsulation efficiencies (L Dopa: ~9% and 70µg/mg of nanogels, Cyt C: ~30% and 10µg/mg of nanogels respectively for both the drugs. The release kinetics of L-Dopa, monitored using UV-vis spectrophotometry was observed to be rather slow (over several hours) with highest release happening under a combination of high temperature (above VPTT) and acidic conditions. However, the release of L-Dopa from nanogel coated Fe@Au NPs was the fastest, accounting for release of almost 87% of the initially loaded drug in ~30 hours. The chemical structure of the drug, drug incorporation method, location of the drug and presence of Fe@Au NPs largely alter the drug release mechanism and the kinetics of these nanogels and Fe@Au NPs coated with nanogels.

Keywords: controlled release, nanogels, volume phase transition temperature, l-dopa

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Authors: A. Kabir, D. Boulainine, I. Bouanane, N. Benslim, B. Boudjema, C. Sedrati

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SnO₂ is an n-type semiconductor with a direct gap of about 3.6 eV. It is largely used in several domains such as nanocrystalline photovoltaic cells. Due to its interesting physic-chemical properties, this material was elaborated in thin film forms using different deposition techniques. It was found that SnO₂ properties were directly affected by the deposition method parameters. In this work, the RGTO method (Rheotaxial Growth and Thermal Oxidation) was used to deposit elaborate SnO₂ thin films. This technique consists on thermal oxidation of the Sn films deposited onto a substrate heated to a temperature close to Sn melting point (232°C). Such process allows the preparation of high porosity tin oxide films which are very suitable for the gas sensing. The films structural, morphological and optical properties pre and post thermal oxidation were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Visible spectroscopy and Fourier transform infrared spectroscopy (FTIR) respectively. XRD patterns showed a polycrystalline structure of the cassiterite phase of SnO₂. The grain growth was found affected by the oxidation temperature. This grain size evolution was confronted to existing grain growth models in order to understand the growth mechanism. From SEM images, the as deposited Sn film was formed of difference diameter spherical agglomerations. As a function of the oxidation temperature, these spherical agglomerations shape changed due to the introduction of oxygen ions. The deformed spheres started to interconnect by forming bridges between them. The volume porosity, determined from the UV-Visible reflexion spectra, Changes as a function of the oxidation temperature. The variation of the crystalline fraction, determined from FTIR spectra, correlated with the variation of both the grain size and the volume porosity.

Keywords: tin oxide, RGTO, grain growth, volume porosity, crystalline fraction

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Authors: Fani Firmahandari

Abstract:

The development learning module physics based on guided inquiry approach on model cooperative learning type STAD (Student Team Achievement Division) in the main subject of temperature and heat. The research development aimed to produce physics learning module based on guided cooperative learning type STAD (Student Team Achievement Division) in the main subject of temperature and heat to the student in X class. The research method used Research and Development approach. The development procedure of this module includes potential problems, data collection to meet the need, product design, and feasibility of this module. The impact of learning can be seen or observed clearly when the learning process takes place, the teachers or the students already implemented measures cooperative learning model type STAD, so that the learning process goes well, the interaction of teachers and students, students with student looks good, besides that students can interact and work together in group.

Keywords: cooperative learning type STAD (student team achievement division), development, inquiry, interaction students

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Authors: Liang-Yi Lin, Hsunling Bai

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In this work, transition metal (metal= Co, Fe, Ni, Cu, and Mn) modified cerium oxide catalysts supported on mesoporous aluminosilicate particles (Ce/Al-MSPs) were prepared using waste silicate as the precursors through aerosol-assisted flow process, and their catalytic performances were investigated for acetone incineration. Tests on the bimetallic Ce/Al-MSPs and Mn/Al-MSPs and trimetallic Mn-Ce, Fe-Ce, Co-Ce, Ni-Ce, and Cu-Ce/Al-MSPs in the temperature range of 100-300 oC demonstrated that Ce was the main active metal while Mn acted as a suitable promoter in acetone incineration reactions. Among tested catalysts, Mn-Ce/Al-MSPs with a Mn/Ce molar ratio of 2/1 exhibited the highest acetone catalytic activity. Moreover, the synergetic effect was observed for trimetallic Mn-Ce/Al-MSPs on the acetone removal as compared to the bimetallic Ce/Al-MSPs or Mn/Al-MSPs catalysts.

Keywords: acetone, catalytic oxidation, cerium oxide, mesoporous silica

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Authors: Antonina Semakova, Karim Mynbaev, Nikolai Bazhenov, Anton Chernyaev, Sergei Kizhaev, Nikolai Stoyanov

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At present, heterostructures are used for fabrication of almost all types of optoelectronic devices. Our research focuses on the optoelectronic properties of InAs(Sb) solid solutions that are widely used in fabrication of light emitting diodes (LEDs) operating in middle wavelength infrared range (MWIR). This spectral range (2-6 μm) is relevant for laser diode spectroscopy of gases and molecules, for systems for the detection of explosive substances, medical applications, and for environmental monitoring. The fabrication of MWIR LEDs that operate efficiently at room temperature is mainly hindered by the predominance of non-radiative Auger recombination of charge carriers over the process of radiative recombination, which makes practical application of LEDs difficult. However, non-radiative recombination can be partly suppressed in quantum-well structures. In this regard, studies of such structures are quite topical. In this work, electroluminescence (EL) of LED heterostructures based on InAs(Sb) epitaxial films with the molar fraction of InSb ranging from 0 to 0.09 and multi quantum-well (MQW) structures was studied in the temperature range 4.2-300 K. The growth of the heterostructures was performed by metal-organic chemical vapour deposition on InAs substrates. On top of the active layer, a wide-bandgap InAsSb(Ga,P) barrier was formed. At low temperatures (4.2-100 K) stimulated emission was observed. As the temperature increased, the emission became spontaneous. The transition from stimulated emission to spontaneous one occurred at different temperatures for structures with different InSb contents in the active region. The temperature-dependent carrier lifetime, limited by radiative recombination and the most probable Auger processes (for the materials under consideration, CHHS and CHCC), were calculated within the framework of the Kane model. The effect of various recombination processes on the carrier lifetime was studied, and the dominant role of Auger processes was established. For MQW structures quantization energies for electrons, light and heavy holes were calculated. A characteristic feature of the experimental EL spectra of these structures was the presence of peaks with energy different from that of calculated optical transitions between the first quantization levels for electrons and heavy holes. The obtained results showed strong effect of the specific electronic structure of InAsSb on the energy and intensity of optical transitions in nanostructures based on this material. For the structure with MQWs in the active layer, a very weak temperature dependence of EL peak was observed at high temperatures (>150 K), which makes it attractive for fabricating temperature-resistant gas sensors operating in the middle-infrared range.

Keywords: Electroluminescence, InAsSb, light emitting diode, quantum wells

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Authors: Ibrahim A. Adeniran, Rui F. Zhu, Man S. Wong

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Owing to the insufficiency in the spatial representativeness and continuity of in situ temperature measurements from weather stations (WS), the use of temperature measurement from WS for large-range diurnal analysis in heterogenous landscapes has been limited. This has made the accurate estimation of land surface temperature (LST) from remotely sensed data more crucial. Moreover, the study of dynamic interaction between the atmosphere and the physical surface of the Earth could be enhanced at both annual and diurnal scales by using optimal LST data derived from satellite sensors. The tradeoff between the spatial and temporal resolution of LSTs from satellite’s thermal infrared sensors (TIRS) has, however, been a major challenge, especially when high spatiotemporal LST data are recommended. It is well-known from existing literature that polar satellites have the advantage of high spatial resolution, while geostationary satellites have a high temporal resolution. Hence, this study is aimed at designing a framework for the cross-comparison of LST data from polar and geostationary satellites in a heterogeneous landscape. This could help to understand the relationship between the LST estimates from the two satellites and, consequently, their integration in diurnal LST analysis. Landsat-8 satellite data will be used as the representative of the polar satellite due to the availability of its long-term series, while the Himawari-8 satellite will be used as the data source for the geostationary satellite because of its improved TIRS. For the study area, Hong Kong Special Administrative Region (HK SAR) will be selected; this is due to the heterogeneity in the landscape of the region. LST data will be retrieved from both satellites using the Split window algorithm (SWA), and the resulting data will be validated by comparing satellite-derived LST data with temperature data from automatic WS in HK SAR. The LST data from the satellite data will then be separated based on the land use classification in HK SAR using the Global Land Cover by National Mapping Organization version3 (GLCNMO 2013) data. The relationship between LST data from Landsat-8 and Himawari-8 will then be investigated based on the land-use class and over different seasons of the year in order to account for seasonal variation in their relationship. The resulting relationship will be spatially and statistically analyzed and graphically visualized for detailed interpretation. Findings from this study will reveal the relationship between the two satellite data based on the land use classification within the study area and the seasons of the year. While the information provided by this study will help in the optimal combination of LST data from Polar (Landsat-8) and geostationary (Himawari-8) satellites, it will also serve as a roadmap in the annual and diurnal urban heat (UHI) analysis in Hong Kong SAR.

Keywords: automatic weather station, Himawari-8, Landsat-8, land surface temperature, land use classification, split window algorithm, urban heat island

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