17 research outputs found
Numerical Simulation and Experimental Study of Comfort Air Conditioning Influenced by Bottom-supply and Stratum Ventilation Modes
Defrosting Performance Improvement of Air-Source Heat Pump Combined Refrigerant Direct-Condensation Radiant Floor Heating System with Phase Change Material
Traditional defrosting methods applied to solve frosting problems of air-source heat pumps operating in cold periods may reduce heat capacity of the system and decrease indoor thermal comfort. In order to improve the performance of air-source heat pump (ASHP) and maintain indoor temperature in defrosting conditions, an air-source heat pump combined with a refrigerant direct-condensation radiant floor heating system with phase change material is proposed and evaluated in this study. Two radiant floor heating terminals with and without composite phase change material modules were compared through experiments. A composite phase change material based on dodecanoic acid-tetradecanol-hexadecanol mixture and expanded graphite was investigated for this application. Experimental results indicate that both heat fluxes of two comparing terminals are higher than 70 W/m2 in heating condition. At the same time, the floor surface temperature, indoor air temperature, and heating capacity of the terminal with composite phase change material modules are higher than those without composite phase change material modules in defrosting condition. This suggests that the proposed system with composite phase change material modules can improve indoor thermal comfort in defrosting condition as well as satisfy the heating requirement in heating condition
Optimization of High Hydrostatic Pressure Treatments on Soybean Protein Isolate to Improve Its Functionality and Evaluation of Its Application in Yogurt
This work aimed to improve the functional properties of soybean protein isolate (SPI) by high hydrostatic pressure (HHP) and develop SPI incorporated yogurt. Response surface methodology (RSM) was used to optimize the HHP treatment parameters, including pressure, holding time, and the ratio of SPI/water. Water holding capacity, emulsifying activity index, solubility, and hardness of SPI gels were evaluated as response variables. The optimized HPP treatment conditions were 281 MPa of pressure, 18.92 min of holding time, and 1:8.33 of SPI/water ratio. Water and oil holding capacity, emulsifying activity, and stability of SPI at different pH were improved. Additionally, relative lipoxygenase (LOX) activity of HHP treated SPI (HHP-SPI) was decreased 67.55 ± 5.73%, but sulphydryl group content of HHP-SPI was increased 12.77%, respectively. When incorporating 8% of SPI and HHP-SPI into yogurt, the water holding capacity and rheological properties of yogurt were improved in comparison with yogurt made of milk powders. Moreover, HHP-SPI incorporated yogurt appeared better color and flavor
Impact of restrictive red blood cell transfusion strategy on thrombosis-related events: A meta-analysis and systematic review
10.1111/vox.13274VOX SANGUINIS1177887-89
Optimizing Spatial Channel Networks (SCNs) in Hierarchical Optical Cross-Connect (HOXC) architectures: Impact of wavelength switching granularity on performance
The increasing demand for network bandwidth highlights the critical need to enhance optical transmission systems. Utilizing the entire C-band for a single optical channel(OCh) eliminates the requirement for wavelength switching, prompting the emergence of spatial channel networks (SCNs). SCNs transform the optical layer into hierarchical spatial division multiplexing (SDM) and wavelength division multiplexing (WDM) layers through the implementation of hierarchical optical cross-connects (HOXCs). A HOXC comprises a spatial channel cross-connect (SXC) for spatial bypass switching and multiple wavelength cross-connects (WXCs) for wavelength channel switching, ensuring efficient optical transmission. Therefore, the design of the HOXC plays a pivotal role in determining both the device cost and network performance in SCNs. This study investigates the impact of wavelength switching granularity on core-selective switch (CSS)-based HOXC architectures. We propose an adaptive dynamic Routing, Spatial Channel, and Spectrum Assignment (RSCSA) algorithm to solve routing and resource allocation problems in SCNs. By examining SCN designs with varying wavelength switching granularities, we assess the overall network deployment cost, considering both network throughput and spectrum resource utilization. Our findings indicate that adjusting the granularity of wavelength switching in SCNs can significantly affect device costs and performance, highlighting the importance of identifying an optimal SCN design that strikes a balance between these factors. These insights offer valuable guidance for the practical planning and management of future SCN deployments
Experimental and numerical study on the heat transfer performance of the radiant floor heating condenser with composite phase change material
Traditional hot-water ASHP systems have disadvantage of low energy efficiency due to the requirement of secondary heat exchange. To maintain the stability of indoor air temperature during defrosting, the existing ASHP systems adopt heat exchanger to store heat, which increases the system complexity. To overcome these obstacles, a novel ASHP system integrated with radiant floor heating condenser (RFHC) is proposed, which uses refrigerant as working fluid to exchange heat with indoor environment directly. In addition, the composite phase change material (CPCM) is added in the RFHC for heat storage. Experiments are conducted and results show that compared with traditional ASHP systems, the proposed system has higher energy efficiency and can reduce indoor air temperature fluctuation under defrosting condition. A detailed numerical model of the RFHC is established and validated with the experimental data, and then the impacts of the operating and structural parameters on the heat transfer performance of the RFHC system are investigated. Results show that under the indoor air temperature of test room keeps at 18.0 oC, the optimal operating condition of this system is the condensing temperature with 38.0 oC and the refrigerant mass flow rate with 3.8 kg· h-1. The optimal structural scheme of the RFHC is the copper pipe spacing with 0.25 m and the length of copper pipe with 12.0 m
Isolation, Characterization and Anti-Multiple Drug Resistant (MDR) Bacterial Activity of Endophytic Fungi Isolated from the Mangrove Plant, Aegiceras corniculatum
Purpose: To isolate, characterize and assess the anti-multiple-drug resistant (MDR) bacterial potential of culturable endophytes from A. corniculatum in Beibu Gulf, China.Methods: The plant parts were collected from healthy-looking A. corniculatum. The endophytes were isolated and identified by colonial morphology and macroscopic characteristics and DNA sequencing offungal ITS region, and then grouped by phylogenetic analysis. Antibacterial activity was assayed using five human pathogenic bacteria (B. cereus, P. aeruginosa, E. coli, K. pneumoniae and A. baumanii) out of which two of them were MDR bacteria. Ethyl acetate extracts from endophytes were prepared, and the minimum inhibitory concentration (MIC) of 3 endophytes was tested using serial 2-fold dilutions of the extract.Results: 61 endophytes obtained from A. corniculatum were grouped into 6 genera (Colletotrichum, Alternaria, Phomopsis, Pestalotiopsis, Guignardia, Cladosporium). Colletotrichum and Pestalotiopsis were the most frequent genera, accounting for colonization frequencies (CF) of 29.5 and 37.7%. Among the rare morphotypes, Alternaria, Phomopsis, Guignardia and Cladosporium were the infrequent genera, accounting for CF ranging from 3.2 to 13.1%. Overall, 3 endophytes, including Glomerella,Guignardia, and Cladosporium, all isolated from the leaves, showed inhibitory activity against five test bacteria in vitro. The endophyte, Colletotrichum, inhibited two MDR K. pneumoniae and A. baumanii,while Guignardia inhibits MDR K. pneumoniae. The MIC of the extract of Colletotrichum against MDR K. pneumoniae was 4 µg/ml, against MDR A. baumanii was 0.5 µg/ml, while MIC of Guignardia to K. pneumoniae was 8 µg/ml.Conclusion: The study demonstrates that endophytes from mangrove plant A. corniculatum were a fascinating fungal reservoir against MDR pathogenic bacteria.Keywords: Endophytic fungi, Multiple drug-resistant Bacteria, Mangrove plant, Aegiceras corniculatu