Suitable Temperature Research Articles

Selenium Nanoparticles: A Comprehensive Examination of Synthesis Techniques and Their Diverse Applications in Medical Research and Toxicology Studies.

Selenium is a trace and necessary micronutrient for human, animal, and microbial health. Many researchers have recently been interested in selenium nanoparticles (SeNPs) due to their biocompatibility, bioavailability, and low toxicity. As a result of their greater bioactivity, selenium nanoparticles are widely employed in a variety of biological applications. Physical, chemical, and biological approaches can all be used to synthesize selenium nanoparticles. Since it uses non-toxic solvents and operates at a suitable temperature, the biological technique is a preferable option. This review article addresses the processes implemented in the synthesis of SeNPs and highlights their medicinal uses, such as the treatment of fungi, bacteria, cancer, and wounds. Furthermore, we discuss the most recent findings on the potential of several biological materials for selenium nanoparticle production. The precursor, extract, process, time, temperature, and other synthesis criteria will be elaborated in conjunction with the product's physical properties (size, shape, and stability). The synergies of SeNP synthesis via various methods aid future researchers in precisely synthesizing SeNPs and using them in desired applications.

PREPARATION AND CHARACTERISATION OF ZnO THIN FILMS DEPOSITED BY RF SPUTTERING METHOD

Zinc oxide (ZnO) thin films deposited on corning glass substrates at 100ºC substrate temperature by radio frequency deposition were annealed the open air and icrowave oven at 150ºC. The influence of open-air annealing (OAA) and microwave annealing (MWA) were studied. The results obtained showed that MWA annealing can improve not only the crystal but also the optical properties of the ZnO thin films. A high transmittance is obtained in all the annealed samples (S1, S2, S4 and S5) demonstrating >90% at 650 nm wavelength. Reflectance in all the samples was < 29% with a minimum standing at 23.78% as recorded for sample S5. The band gap for the annealed samples (S1, S2, S4 and S5) was determined at 3.26 eV, 3.32 eV, 3.29 eV and 3.34 eV respectively. Absorption coefficient stood at 0.0225 cm-1, 0.0179 cm-1, 0.0180 cm-1, 0.0186 cm-1 and 0.0181 cm-1 for the as-deposited sample and the respectively. The optical and structural properties analysis showed that OAA and MWA annealing at suitable temperatures considered can significantly improve some properties of the ZnO thin films making the films suitable for applications in optoelectronics and photovoltaics.

Zn–N bonds boost interfacial charge transfer in ZnO/Nitrogen-Doped porous carbon Schottky heterojunction for enhanced photocatalytic sterilization

Although heterogeneous photocatalytic sterilization can avoid secondary pollution and achieve broad spectrum antibacterial effects, its low disinfection efficiency seriously hinders its development. Exploring and achieving precise electron-transfer channels in the interface of heterogeneous systems are an effective method to enhance photocatalytic sterilization. Herein, we designed a chemical Zn–N bonded nitrogen-doped porous carbon-loaded zinc oxide (ZnO/NC) Schottky heterojunction photocatalyst through oxidizing and carbonizing ZIF-8 in-situ at suitable temperatures. The Zn–N accurately facilitated the photogenerated electrons transfer from the conduction band (CB) site of ZnO to the NC surface as active site. Furthermore, the NC as carrier enhanced the light-absorption capacity (746 nm) of Schottky heterojunction and functioned as active site to promote the generation of reactive oxygen species (ROS). In addition, the slow-release effect of zinc ions (Zn2+) from ZnO contributed to the accelerated death of bacteria. As a result, under simulated sunlight conditions, the ZnO/NC-400(1 h) Schottky heterojunction demonstrated an impressive antibacterial efficiency of 99.33 % against Escherichia coli, consistently exceeding 95 % in repeated experiments. This work presents a controllable and encouraging approach for constructing heterojunction with effective antibacterial properties.

Fabrication of carboxymethyl cellulose-based thermo-sensitive hydrogels and inhibition of corneal neovascularization

Corneal neovascularization (CNV) is a common multifactorial sequela of anterior corneal segment inflammation, which could lead to visual impairment and even blindness. The main treatments available are surgical sutures and invasive drug injections, which could cause serious ocular complications. To solve this problem, a thermo-sensitive drug-loaded hydrogel with high transparency was prepared in this study, which could achieve the sustained-release of drugs without affecting normal vision. In briefly, the thermo-sensitive hydrogel (PFNOCMC) was prepared from oxidized carboxymethyl cellulose (OCMC) and aminated poloxamer 407 (PF127-NH2). The results proved the PFNOCMC hydrogels possess high transparency, suitable gel temperature and time. In the CNV model, the PFNOCMC hydrogel loading bone morphogenetic protein 4 (BMP4) showed significant inhibition of CNV, this is due to the hydrogel allowed the drug to stay longer in the target area. The animal experiments on the ocular surface were carried out, which proved the hydrogel had excellent biocompatibility, and could realize the sustained-release of loaded drugs, and had a significant inhibitory effect on the neovascularization after ocular surface surgery. In conclusion, PFNOCMC hydrogels have great potential as sustained-release drug carriers in the biomedical field and provide a new minimally invasive option for the treatment of neovascular ocular diseases.

Thermal performance of solar flat plate collector using energy storage phase change materials

AbstractThe present study has been carried out to improve the overall efficiency of a conventional flat plate solar collector (FPSC) using two different heat storage phase change materials (PCMs). Two grades of paraffin wax—Paraffin‐P116 (PCM‐1) and Paraffin‐5838 (PCM‐2) as PCM are selected for the analysis based on their high heat fusion rate, low thermal conductivity, and suitable phase transition temperature. The present code has been validated with experimental results and it showed a maximum error of 6.43% in predicting the water outlet temperature. Absorber plate temperature, useful heat transfer rate, water outlet temperature and efficiencies are estimated to improve the performance of FPSC with and without PCM for various flow rates (15 lph and 30 lph) with two different weights of PCM (9 kg and 14 kg) for three different locations in India, [Chennai (13.0827° N, 80.2707° E), Bengaluru (12.9716° N, 77.5946° E), and Delhi (28.7041° N, 77.1025° E)]. The maximum increment in the efficiency of FPSC with the use of PCM‐1 is 19.59% and with the use of PCM‐2 is 16.53%. Using 14 kg of PCM‐1 with the conventional FPSC at water inlet flow rate of 15 lph increases the overall thermal efficiency up to 19.59% compared with conventional FPSC. The maximum increase in the percentage of efficiency with PCM‐1 from conventional FPSC for different cases of 15 lph‐09 kg is 16.34%, 15 lph‐14 kg is 19.59%, 30 lph‐09 kg is 14.57% and 30 lph‐14 kg is 18.45%. From the present study, it can be concluded that the overall efficiency of FPSC is increased with the use of 14 kg of PCM‐1 with conventional FPSC at the inlet water flow rate of 15 lph.

Charge Assessment for Nitrate-Based Salt as a Phase Change Material for a Medium-Temperature Latent Storage Tank

Abstract The present study assesses the heat characteristic of the nitrate-salt mixture as a phase change material (PCM) for a medium-temperature latent storage system (LSS). Two binary and ternary mixtures are evaluated, which demonstrate different thermal behaviour. The highest melting and latent heat capacity is obtained by KNO3(0.4)/NaNO3(0.6) at 223.8 °C and 161.5 J/g. However, it has a higher supercooling degree with a partial phase transition between 217.6 °C and 251.5 °C, making it unfeasible for a medium-temperature LSS tank. The ternary mixture (TM) with NaNO2(0.4)/KNO2(0.53)/NaNO3(0.7) demonstrates a stable phase transition with minimum partial phase transition (22.1 °C) and suitable heat of fusion (98.1 J/g). Further evaluation through static thermal profiling demonstrates that the TM has a notable performance during solid-sensible charge with a charge level indicator (CLI) around 45.3 %–49.1 %. The TM can be charged up to 85.7 % until the end stage of the phase transition. It promotes a better storage capacity with suitable performance since the system can be charged effectively at a suitable temperature range (< 160 °C) for various applications. The micrograph observation indicates some dispersed particles and local agglomeration, which makes phase stabilization as an advantageous method to promote a stable phase change process. The TM can be considered a suitable PCM for a medium-temperature LSS tank that allows for a better solar thermal renewable system operation.

Diagnostics and characterization of a novel multi gas layer RF atmospheric pressure plasma jet for polymer processing

The quest to employ cold plasma sources at atmospheric pressure in polymer processing has emerged as a potent driving force behind their development. Atmospheric pressure operation of plasma jets provides potential cost reductions as well as easier handling and maintenance. In addition, their unique advantage of remote operation allows the substrate to be placed outside the source boundaries. This latter feature makes it easier to process complex three-dimensional objects and to integrate plasma jets into existing production lines. Although conventional atmospheric pressure plasma jet (APPJ) sources have undergone significant advancements in their design and construction, they have reached their technical and technological thresholds in several domains, thereby also impeding further enhancements in material processing applications. To cope with this issue, this work introduces a promising APPJ (named MPPJ3) working in a three co-axial gas layer geometry, incorporating the capability of aerosol and shield gas introduction leading to a configuration rich in reactive plasma species with controllable size and suitable temperature for polymer processing. A parametric study on the novel MPPJ3 device is carried out and plasma characteristics, such as reactive plasma species and temperatures, are determined by means of optical emission spectroscopy (OES), laser scattering, and infrared (IR) camera imaging whereas the fluid dynamics are analyzed using computational fluid dynamics (CFDs) and Schlieren imaging. The obtained promising results clearly show the flexibility and adaptability of the MPPJ3 device for polymer processing applications.

Study on Deformation Behavior and Mechanical Properties of 42CrMo High-Strength Steel with Multi-Station Warm Upsetting

In order to find out the deformation behavior and mechanical properties of 42CrMo steel under warm upsetting conditions, the Gleeble-3500 thermal simulation testing machine was used to carry out a warm upsetting physical simulation experiment on 42CrMo steel. By controlling deformation temperature, strain rate, and constant temperature deformation pass, the microstructure evolution rule under different warm upsetting conditions was analyzed, and its hardness value was measured. Then, the simulation experiment is carried out based on the Deform-3D finite element platform. The results show that, with the increase in deformation temperature, 42CrMo steel has a temperature rise softening effect, which significantly reduces the peak value of rheological stress. At 650 °C, the maximum peak value of rheological stress is only 45.3% of that of cold upsetting deformation at room temperature, and the stress-strain curve tends to be gentle at the plastic deformation stage, which is the most suitable temperature for warm upsetting deformation. The maximum peak flow stress of 42CrMo steel increases with the increase in strain rate, but the number of deformation channels has little influence on the stress-strain curve. The warm, upsetting deformation can refine the internal grain structure significantly, and the grain refinement mechanism is mechanical crushing. When the temperature is slightly higher, the broken grain will recover, and the grain size will grow. During the process of warm upsetting, the strain rate has a great influence on the microhardness of the sample. The deformation pass has little influence on the hardness, and the hardness increases slightly with the increase in the deformation pass. Through the Deform-3D simulation, the correlation coefficient R and the average absolute relative error (AARE) between the simulation value and the experimental value were calculated, and the correlation coefficient R-value was 0.9948, and the average absolute relative error (AARE) was 2.05%, indicating that the simulation can accurately reflect the relationship between displacement and applied load.

Influence of Pasteurisation (Conventional vs. Radiofrequency) and Chill Storage on Retention of Ascorbic Acid, Tocopherol and Carotenoids in Salmorejo.

Salmorejo, a Mediterranean tomato-oil puree, is considered a dietary source of antioxidant vitamins C and E and carotenoids lycopene and β-carotene, the latter endowed with provitamin A activity. However, these antioxidants can be degraded in oxidation reactions catalysed or not by enzymes during pasteurisation and storage treatments used to stabilise the salmorejo before consumption. Due to its better penetration, the use of dielectric heating by radiofrequency (RF) may improve results of pasteurisation in this product. The objective was to assess the effects of pasteurisation temperature (70-100 °C, at 5 °C intervals) and storage time (0-5 months, at one-month intervals) on levels of ascorbic acid, α-tocopherol and carotenoids and antioxidant capacity (AC) in salmorejo pasteurised (over 10 s) by conventional (CH) or RF continuous heating. Two successive experiments were conducted to select an adequate pasteurisation temperature for use in the shelf-life study. Pasteurisation upon tested conditions allows a good retention of salmorejo antioxidants. Either CH or RF pasteurisers can be used with similar results. Vitamin C (L-ascorbic + dehydroascorbic acids) was more abundant (15-19 mg 100 g-1) than carotenoids (0.9-2.6 mg 100 g-1) (all-trans + cis lycopene and β-carotene) and α-tocopherol (0.8-1.2 mg 100 g-1) in the pasteurised product. Using excessively low temperatures (70 °C) resulted in partial losses of the three antioxidants, possibly due to oxidase residual activities. Intensifying thermal treatment improved this issue with minor losses of the thermolabile vitamin C and increased carotenoid content. Using a suitable temperature (80 °C) did not prevent most vitamin C from being degraded by the first month, while α-tocopherol, and, to a lesser extent, carotenoids, showed good retention levels during shelf life under refrigeration. Vitamins C and E and carotenoids, either by degradation, regeneration or releasing, likely contribute to the AC in salmorejo. Phenolic antioxidant response, radical-scavenging activities and redox potential values confirmed this finding. The pasteurised-chilled salmorejo shows good antioxidant properties with potential health implications, a positive nutritional aspect for consumers of this tomato-oil homogenate. The losses of antioxidants and AC due to pasteurization would be of little relevance compared to the losses accumulated during shelf life.

Spatiotemporal Distribution Analysis of Spatial Vitality of Specialized Garden Plant Landscapes during Spring: A Case Study of Hangzhou Botanical Garden in China

Specialized gardens, as integral components of botanical gardens, bear multiple functions, encompassing plant collection and conservation, scientific research, and public education, as well as serving aesthetic and recreational purposes. Their quality profoundly reflects the landscape artistry of botanical gardens, directly influencing the quality of visitors’ enjoyment and the overall experience within the botanical garden. This study aims to investigate the spatial vitality of specialized garden plant landscapes, effectively assessing the usage patterns of plant landscape spaces and promoting the optimal utilization of underutilized spaces. Taking Hangzhou Botanical Garden as a case study, considering the warming climate and suitable temperatures in spring, when most plants enter the flowering period and outdoor visitor frequency increases, the primary observational period focuses on spring to measure the spatial vitality of specialized garden plant landscapes. We obtained data through field measurements and on-site observations. Specifically, We measured and recorded information on plant species, quantity, height, crown width, and growth conditions within the plots. Additionally, we employed ground observations and fixed-point photography to document visitor numbers and activity types. We quantified spatial vitality through four indicators: visitor density, space usage intensity, diversity of age group, and richness of activity type. We explored the spatiotemporal distribution patterns of spatial vitality and investigated the relationship between plant landscape characteristics and spatial vitality using variance analysis and correlation analysis. The results indicate that, in spring, the average spatial vitality index of specialized gardens ranks from highest to lowest as follows: Lingfeng Tanmei (1.403), Rosaceae Garden (1.245), Acer and Rhododendron Garden (0.449), and Osmanthus and Crape Myrtle Garden (0.437). Additionally, the spatial vitality of specialized garden plant landscapes in spring is significantly positively correlated with the ornamental period of specialized plants, characteristics of plant viewing, accessible lawn area, spatial accessibility, and spatial enclosure. Therefore, to create vibrant specialized plant landscapes, managers and planners, when engaging in the planning and design of specialized garden plant landscapes, need to fully consider and respect the visual aesthetics and functional needs of visitors. This study will serve as a theoretical reference for subsequent research on the vitality of plant landscape spaces and other small-scale spaces. It will also provide practical guidance for the construction of plant landscapes in specialized gardens within botanical gardens and other urban green spaces.

Tungsten trioxide coatings prepared by inkjet printing of a water based formulation: structural characteristics and electrophotocatalytic properties

Thin compact layers of monoclinic tungsten trioxide (WO3) were prepared through printing of a water soluble dopamine peroxo-tungstic acid complex (DoPTA). The effect of different layer thicknesses, achieved through the sequential overlapping of layers (from one to five), on the resulting structure and photo(electrochemical) properties was investigated. After a powder XRD analysis, 450 °C was determined to be the most suitable temperature for calcination due to the formation of a crystalline phase of WO3 within a relatively short time (after 1 h) and, at the same time, this temperature does not cause any damage to the glass substrates used for the deposition of the WO3 layers. Linear scanning voltammetry as well as chronoamperometry were used, with periodic illumination, to measure the influence of the number of layers on the final electro-photocatalytic properties. The thickness of the samples prepared ranged from 0.25 µm to 1.25 µm and the three-layer sample was found to have the best performance. It had a thickness of 0.83 µm, and the incident photon to current efficiency (IPCE) was calculated to be 40.8%.

Ethylenediamine functionalized graphene wrapped nano-sulfur structures enhances the performance of Li-S batteries with high sulfur loading

Commercial applications of lithium-sulfur batteries (LSBs) suffer from low sulfur utilization, inadequate cell capacity, and inefficient cycling stability, especially under conditions of poor electrolyte and high sulfur loading. Herein, strategies to load sulfur within the wrapped have been proposed, where the large volume expansion and polysulfide diffusion problems can be suppressed. Simultaneously, maximizing sulfur loading is realized. Nano-sulfur@N-modified graphene oxide (S@EGO) wrapped structures were synthesized by electrostatic adsorption method. The sulfur core was formed by the recrystallization, and the graphene oxide shell was decorated with a trace amount of reducing agent ethylenediamine (EDA). The resulting wrapped particle size is 3 ∼ 5 μm, including 20 ∼ 50 nm nano-sulfur particle size. N-doped GO (EGO) under suitable temperatures (85 °C) exhibits perfect wrapped state and catalytic activity which gives rise to superior battery performances: the discharge-specific capacity decayed from 1010 mAh/g to 440 mAh/g (900 cycles at 1 C) with an average capacity decay rate of 0.0627 % per cycle. Thermogravimetric analysis that the material prepared by this method reached a sulfur loading of 92 wt%, showing a high prospect of application.

Fabrication of shape-stable glycine water-based phase-change material using modified expanded graphite for cold energy storage

A shape-stable glycine water-based phase-change material (GPCM) was fabricated herein via natural adsorption using modified expanded graphite (MEG) as a porous carrier. Cetyltrimethylammonium bromide (CTAB) was introduced as a modifier on the surface of expanded graphite (EG) to synthesise MEG, which improved compatibility between EG and GPCM. Furthermore, the adsorption capacities of EG and MEG on GPCM were compared and analysed. The thermophysical properties of the as-prepared MEG/GPCM composite were evaluated using differential scanning calorimetry. Results revealed that MEG modified with 0.1 g of CTAB (MEG-0.1) had the best compatibility with GPCM and its adsorption capacity increased from 73.96% to 84.05% compared with that of unmodified EG. When the MEG content was 14%, the MEG/GPCM composite had a suitable melting temperature of −5.06 °C and high latent heat of 243.80 J/g. Moreover, the thermal conductivity was 1.836 W/(m⋅K), 216.33% higher than that of GPCM. After 100 thermal cycles, and the melting temperature and latent heat of the MEG/GPCM composite only decreased by 1.38% and 6.15% to −5.13 °C and 228.79 J/g, respectively. Thus, the prepared composites exhibited excellent thermal properties and showed great potential in the application of low-temperature cold energy storage and cold-chain transportation.

Cold Seeps and Heat Flow: Gas Hydrate Provinces Offshore Sakhalin Island

Gas hydrates were found in bottom sediments on the western slope of the Kuril Basin from the side of the Terpeniya Gulf (Okhotsk Sea) at 1020 m depths during expeditions in 2012 and 2013. However, on the eastern slope of the Tatar Strait, gas hydrates were sampled at an unusually shallow 322 m depth. During our research, we identified gas hydrate provinces based on both bottom water and sediment temperature measurement data and heat flow, earthquake, cold seep and sea current data analyses. These provinces have similar hydrological regimes, providing suitable temperature conditions for the existence of gas hydrates, to those at a 322 m depth in the Tatar Strait (Japan Sea) and at 725 and 1020 m depths on the slope of the Kuril Basin (Okhotsk Sea).

Molten Salt Synthesized CaTa4O11:Er3+/Yb3+ with Superior Upconversion Luminescence.

Low phonon tantalate-based phosphors with a layer structure are considered to have excellent upconversion luminescence (UCL) intensity, which could be reduced due to the existence of impure phase defects and inappropriate doped rare earth ions. To improve their UCL performance, we have prepared single-phase CaTa4O11:Er3+/Yb3+ samples by a molten salt synthesis (MSS) using KCl as the reaction medium and compared its UCL properties with counterparts made by a conventional solid-state reaction (SSR) in this study. We have demonstrated that the MSS samples have a much higher UCL intensity under 980 nm laser excitation than the SSR ones due to accurate replacement of Ca2+ sites by Er3+/Yb3+ in high-purity single-phase MSS samples. We have further enhanced the green UCL intensity of the MSS samples by 1.57 times via acid picking (AP). Under 980 nm laser excitation at a high powder density of 61.3 W/cm2, the green UCL intensity of the MSS-AP samples can reach 3.72 times that of the SSR-AP samples. For potential luminescence thermometry applications, the maximum absolute sensitivity (SA) of the MSS-AP samples reaches 0.01316 K-1 at 501 K based on the luminescence intensity ratio. This study shows that CaTa4O11:Er3+/Yb3+ phosphors prepared by the MSS method are single-phase samples with excellent pure green UCL as a suitable temperature sensing material.

Activated Carbons and Chitosan Adsorbents in Removing Contaminants from Water

Being more and more widely used for a variety of water treatments, chitosan and activated carbons are playing an increasingly significant part nowadays. Activated carbons purify water through the pore structure and adsorb ions or other particles. Chitosan also adsorb a large amount of metallic ions and purifies water through the reactions by the functional groups. This paper discusses the different features of the two substances and then gives a comparison between the two types of adsorbents by comparing their characteristics, conditions and applications. Specifically, the suitable temperatures, the specific modifications and solubility are discussed, together with other factors. The difference in their physical and chemical properties plays an important role in the comparison. For physical properties, the activated carbons have strong mechanical strength and are soluble in many types of solvents. By contrast, chitosan is generally soluble in an acidic solution. There are also some differences in the adsorption abilities and ways to purify solutions. Next, chitosan is more easily dissolved in solution with low PH and at room temperature. However, the activated carbons require lower PH and lower temperature to be dissolved. Then, activated carbons are more likely to cause secondary pollution due to the impurities in the activated carbons. The two substances require different modifications to increase the rate of adsorption. As a result, the firms should consider the features of the two types of adsorbents and choose the better one. They should also understand the suitable conditions for each adsorbent.

Preparation and application of low temperature protection materials by Na2SO4·10H2O/PS phase change microcapsules

To find the phase change microcapsule material (MEPCM) with suitable temperature and high heat storage energy. The phase change microcapsules with sodium sulfate decahydrate (Na2SO4·10H2O) as core material and polystyrene (PS) as wall material were prepared by emulsion polymerization. The microcapsule is fixed on the cloth of the overalls by coating method, and the thermoregulation fabric is obtained. The microcapsules were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TG) and infrared spectroscopy (FTIR). Fabrics are tested for durability, air permeability and temperature control. The DSC results show that the Tc and Tm of Na2SO4·10H2O/PS microcapsules are 26.0 °C and 58.0 °C, respectively, and the ΔHc and ΔHm are 64.0 J g−1 and 121.1 J g−1, respectively. The TG results show that the first weight loss temperature range is 104.1 ∼136.7 °C, and the second weight loss temperature range is 395.5 ∼434.6 °C. The infrared spectral characteristic peaks of microcapsules include all the characteristic peaks of Na2SO4·10H2O and PS. In the range of microcapsule phase transition temperature, the cloth treated with 0.5 g MEPCM and 1.5 g MEPCM delayed the temperature change by 16.0 ∼23.0 °C and 10.0 ∼18.0 °C, respectively, compared with the blank cloth. The fabric treated with 0.5 g microcapsules was subjected to 100 and 300 heating/cooling cycles. Compared with before and after the cycles, the fabric after thermal shock cycles showed a 4.15% and 3.56% reduction in delayed temperature changes rate in a rising and falling temperature environment. Therefore, Na2SO4·10H2O/PS microcapsule material can achieve the goal of heat storage and energy storage, and can be used as a low-temperature operation protection material.

Hydrogel-stabilized supercooled salt hydrates for seasonal storage and controlled release of solar-thermal energy

Seasonal storage of solar-thermal energy within salt hydrate phase change materials (PCMs), which are known for their large latent heat capacity, suitable phase change temperature range and cost-effectiveness, has garnered...

Bismuth-oxide nanoparticles: study in a beam and as deposited.

Bi2O3 is a promising material for solid-oxide fuel cells (SOFC) due to the high ionic conductivity of some phases. The largest value is reached for its δ-phase, but it is normally stable at temperatures too high for SOFC operation, while nanostructured oxide is believed to have more suitable stabilization temperature. However, to manufacture such a material with a controlled chemical composition is a challenging task. In this work, we investigated the fabrication of nanostructured Bi2O3 films formed by deposition of free Bi-oxide nanoparticles created in situ. The particle-production method was based on reactive sputtering and vapour aggregation. Depending on the fabrication conditions, the nanoparticles contained either a combination of Bi-metal and Bi-oxide, or only Bi-oxide. Prior to deposition, the free particles were probed in the beam - by synchrotron-based photoelectron spectroscopy (PES), which allowed assessing their composition "on the-fly". The nanoparticle films obtained after deposition were studied by PES, scanning electron microscopy, transmission electron microscopy, and electron diffraction. The films' chemical composition, grain dimensions, and crystal structure were probed. Our analysis suggests that our method produced Bi-oxide films in more than one polymorph of Bi2O3.

Performance Study of Intermittent Heating Mode Combining Air‐Source Heat Pump with Radiator in Hot Summer and Cold Winter Zones of China

An intermittent heating mode combining air‐source heat pumps and radiators (ASHP‐R) was proposed to meet the time‐sharing heating demand of office workers’ residential buildings in hot summer and cold winter zones. Taking Hefei City as an example, the heating performance of the ASHP‐R system under intermittent operation was experimentally studied from January 18 to 21, 2017. Based on the data on a typical day (January 19), the variation characteristics of thermal parameters and thermal comfort of heating rooms were analyzed, and the economic and environmental benefits of the ASHP‐R system were evaluated. The results show that the water supply temperature of 60°C at the startup stage can rapidly increase the indoor air temperature; in the stable stage, the water supply temperature is 40°C, the indoor air maintains a suitable temperature and relative humidity, and the indoor thermal environment is basically unaffected by the change in outdoor temperature and humidity; the inner surface temperature of the envelope (except the window) presents a similar trend to the indoor air temperature, which reduces the asymmetry of the thermal radiation field around the human body. The air temperature distribution in the human activity area is uniform, and the indoor PMV is in an acceptable, comfortable, and satisfactory state; compared with all‐day continuous heating with an air‐source heat pump, the expense can be saved by 24.4% (by 21.5 yuan/m2) in each heating season, and the system can reduce the emissions of CO2, SO2, and NOX by 988, 29.73, and 14.86 kg/year, respectively. Therefore, the system exhibits good environmental performance and economic performance.