446494 research outputs found
Sort by
Development of Energization-Regenerative Solid-State Dehumidification Elements based on PEDOT: PSS/PVA Composites and Feasibility Study for Application in Desiccant Air-Conditioning Systems
No full textThis study focused on the development of a composite dehumidification material based on polyvinyl alcohol (PVA)-modified poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). PEDOT:PSS is known for its high electrical conductivity, whereas PSS exhibits inherent moisture absorption properties. However, pure PEDOT:PSS films are mechanically fragile and are difficult to use as self- supporting membranes. To address this limitation, PVA was introduced as a structural reinforcement material. Five composite films with different PEDOT:PSS-to-PVA ratios were prepared, and their microstructures, mechanical strengths, electrical conductivities, and dehumidification properties were systematically evaluated. The experimental results identified a composite formulation with a good balance among electrical conductivity, moisture absorption, and structural stability. This lays the foundation for future studies on electrically driven dehumidification and material design
An experimental study on exposure risks in a double-bed patient room with different air distribution methods
No full textHospital environments have higher requirements for infection control on the health of occupants. This study aims to compare air distribution effects on reducing healthcare exposure risks in a simulated double-bed patient room, focusing on key parameters such as airflow patterns, heat gain, air distribution methods, and exhaust locations. In the experimental study, tracer gas (SF6) was used to simulate airborne aerosols from an infected patient by a thermal breathing manikin. A four-way nozzle diffuser (ND) for mixing ventilation and a dynamic protective airflow panel system (DPP) for personalized ventilation were utilized and compared as two different air distribution methods. The results showed that cases with a high airflow rate of 80 L/s decreased the concentration level, from an average of 22.8-26.5 ppm to 10.5-12.3 ppm compared to conditions with a lower rate of 40 L/s. In addition, the standard deviation (SD) of concentration was 3.5 and 1.1 ppm using DPP with 80 L/s airflow rate under a heat gain level of 17 W/m2 and 29 W/m2, presenting a stable concentration with high heat gains. The dilution ratios for ND and DPP fluctuated at the airflow rate of 80 L/s. While with low airflow rate of 40 L/s, they had no significant differences in removing particles. Exhaust locations did not affect contamination removal in the double-bed patient room
Impact of environmental factors on personal comfort system’s performance
No full textPersonal comfort systems (PCS) offer energy-efficient solutions for improving thermal comfort by targeting individual needs rather than conditioning entire spaces. This study systematically evaluates how environmental factors such as air temperature, humidity, and air velocity affect PCS performance in both heating and cooling modes. Analyzing data from 64 studies, we found that PCS are most effective in extreme climates, significantly enhancing thermal sensation and overall comfort in cold & dry and hot & humid conditions, while milder climates show smaller improvements. Higher air velocity of PCS can provide more comfort in cooling mode at higher ambient temperatures. Regression analysis revealed significant correlations between air velocity and comfort, suggesting that air velocity also plays a dominant role in PCS effectiveness. These findings highlight the importance of PCS optimization and integration in extreme climates to maximize occupant comfort while reducing HVAC energy consumption. Future research should focus on optimizing PCS for specific environmental conditions and integrating user-controlled adaptive strategies
Optimization of Heating Systems for Small Towns in Coal-Resource-Based Cities under Low-Carbon Transition
No full textCoal-resource-based cities serve as crucial energy supply bases in China. However, their small towns persistently face challenges of high-carbon and inefficient heating systems due to low heat load density, insufficient pipeline coverage, and poor long-distance heat transmission efficiency. This study takes a typical coal-resource-based city in Northwest China as a case study to conduct a comparative analysis of four heating solutions: coal-fired boiler heating, long-distance combined heat and power (CHP) transmission, photovoltaic (PV)-driven air-source heat pump systems, and wind-PV hybrid power generation integrated with seasonal thermal energy storage. The results demonstrate that traditional coal-fired boiler heating has the lowest cost (21.70 RMB/GJ) but generates substantial annual carbon emissions (212,400 tons). The CHP solution shows significantly higher costs (78.49 RMB/GJ) due to expensive pipeline investments (accounting for 59.5% of total costs). Among the two renewable energy solutions, the wind-PV hybrid system with thermal storage demonstrates optimal comprehensive performance, achieving zero carbon emissions with competitive unit heating costs (25.81 RMB/GJ) and initial investments (889 million RMB). This study concludes that wind-PV hybrid systems with thermal storage represent the optimal pathway for low-carbon heating transition in small towns of coal-resource-based cities, requiring supportive policies to facilitate large-scale implementation
Innovative Breathing Retraining Device: Phase-4 Validation of Clinical Efficacy in Healthy Adults
No full textBackground: Breathing retraining devices are widely used to improve lung function, respiratory muscle performance and breathing efficiency. Conventional devices often lack adjustable resistance, meaningful visual feedback or ergonomic design, which can limit training quality and patient engagement. A novel breathing retraining device was developed through sequential phases involving need analysis, engineering design and accuracy validation. Objectives: The study aimed to evaluate whether the newly designed device could produce measurable improvements in pulmonary function and inspiratory performance, and to determine its usability and acceptability among adult users. Methods: A two-week intervention study was conducted on healthy adults. Participants performed structured breathing retraining using the device under supervised and home-based sessions. Pulmonary function, inspiratory performance and user experience were assessed before and after the intervention. Results: Participants demonstrated notable improvements in key pulmonary parameters, including an increase in forced expiratory volume and sustained maximal inspiration. Inspiratory performance improved consistently across all users. User experience ratings indicated high satisfaction, with positive feedback regarding comfort, visual feedback clarity and ease of resistance adjustment. Conclusion: The novel breathing retraining device effectively enhances pulmonary function and inspiratory performance while offering excellent usability. The findings support its potential application in pulmonary rehabilitation and justify further clinical trials in populations with respiratory impairment
Formulation, physicochemical evaluation, and
No full textEmulgels have shown great promise as a topical drug delivery system for the transport of hydrophobic drugs through the dermis. The present study aimed to develop ergothioneine in the form of an emulgel formulation. During the preparation of emulsions, stability issues were observed during both production and storage, which significantly affected the drug release profile. To address this, ergothioneine was incorporated into an emulgel system to improve stability. Ergothioneine is an anti-protozoal agent used in the treatment of certain protozoal infections, specific anaerobic bacterial strains, and infections of the gastrointestinal and genital tracts. It is also employed prophylactically to prevent infections that may occur after surgery. In this study, ergothioneine emulgels were formulated using three different oils mentha oil, liquid paraffin, and clove oil in combination with gelling agents such as hydroxypropyl methylcellulose (HPMC), sodium alginate, and Carbopol 934. The developed formulations were assessed for various physicochemical parameters, including color, texture, solubility, homogeneity, consistency, swelling index, pH, and in-vitro drug release. Among all the formulations, F3 comprising liquid paraffin and Carbopol 934 exhibited superior drug-release performance compared to the other oil-polymer combinations
Stability-Indicating UV Spectroscopy Using AUC Method for Anticancer Drugs: A Green Chemistry Perspective
No full textThe present research work outlines the development of simple, rapid, specific, precise and accurate UV spectroscopy where the area under the curve (AUC) method was employed to estimate anticancer drugs in their bulk dosage form. A wavelength range of 200–400 nm was selected for the analysis, with methanol used as the solvent throughout the study. We established robust protocols for the simultaneous quantification of multiple anticancer agents. Linearity was observed for Olaparib (OLA), Pazopanib (PAZO) and Abiraterone acetate (ABI) in a range of 2-10ppm, 1-5ppm and 12-20ppm respectively. The methods were optimized and validated with respect to various parameters and were validated according to International Council for Harmonization (ICH) guidelines(Q2R2) Where this method can be successfully applied for routine Quality Analysis
Study of the angular distribution of energy of the generated helical electron beam during multi-pulse laser wakefield acceleration
No full textIn recent research, researchers have generated the helical electron beam (HEB) by the interaction of an intense circularly polarised laser pulse and near-critical dense plasma (NCD). In this process, a new acceleration process of the trapped plasma electrons has been discovered, known as self-matching resonance acceleration (SMRA). In the SMRA region, the trapping and resonance process of the plasma electrons has been established, but this regime uses a lot of input power then to overcome this power, we have used a multi-pulse right circular polarised (RCP) laser pulse in a uniform NCD for the generation of the SMRA regime. During the comparison study of single RCP laser pulse-generated SMRA with two, four, and six RCP laser pulse-generated SMRA in NCD, we have studied the helical modulation of trapped plasma electrons and the corresponding angular distribution of energy of the generated HEB. For this study, we have adopted a particle-in-cell (PIC) simulation approach
A review on spinel chromites and their composites: Synthesis, characterization, and applications
No full textSpinel chromite nanoparticles are highly attractive due to their unique structural, magnetic, optical, and catalytic properties. This review presents an overview of pure and doped spinel chromite with the standard chemical formula ACr2O4 (A = Mg, Ni, Co, Cu, Zn), focusing on the effects of cation substitution at tetrahedral (A) and octahedral (B) sites on their structural and functional behaviour. Various synthesis methods including sol-gel, green synthesis, solid-state, microwave-assisted, and ball milling are summarized, highlighting their impact on particle size, morphology, and crystallinity. Characterization techniques such as XRD, SEM, TEM, PL, UV-Vis., FTIR, and VSM have been carried out to study structural, morphological, optical, electrical, and magnetic properties. The review also emphasizes applications spinel chromites in photocatalysis, gas sensing, antimicrobial activity, and energy storage. Overall, this work provides a clear roadmap for future research and development of spinel chromite-based functional materials
Formulation Geometric Engineering of Biomass-Based Slow-Release Fertilizers for Nutrient Management in Sapric Peat Soils
No full textPeat soils pose critical limitations in agricultural productivity due to nutrient leaching and suboptimal nutrient availability. This study investigates the effectiveness of engineered slow-release fertilizer (SRF) formulations and geometries tailored to tropical sapric and hydrophobic peat, aiming to enhance nutrient retention and plant productivity. Two greenhouse experiments at IPB University evaluated the effects of slow-release fertilizers (SRFs) formulated from biomass compost combined with inorganic components (NPK, sludge, fly ash, and ammonium sulfate) using tapioca flour (5%) as a binder. The SRFs were first prepared and then applied to corn and bock choy. The testing encompassed varied fertilizer compositions and geometrical forms in pellet, crumble, small cylinder, and large cylinder. Cylinder formulation contributed to leaching mitigation, in which the nitrate leaching was improved from 0.14 to only 0.05 mg/m2 in 2 days and from 1.62 to only 0.48 mg/m2 in 35 days after application. The biomass compost-inorganic matrix proved instrumental in promoting nutrient synchronization with crop uptake, which could improve the biomass index from 0.32 at standard fertilizer to 1.20 with cylinder formulation. These findings highlight that strategic formulation and geometric design of SRF, can effectively reduce nutrient losses and substantially improve biomass growth and crop performance in peat-based agriculture