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•The Langmuir Qm was frequently inappropriate applied as adsorption capacity.•The regression Langmuir Qm was highly dependent on the aqueous concentration.•The highest adsorption ...capacity is obtained by a saturated Langmuir isotherm.•Langmuir model regressed by partial isotherm couldn't accurately predict adsorption.
The Langmuir equation, the best known adsorption model in the past century, was extensively applied to describe adsorption isotherms. The saturated adsorption amount (Qm) obtained from the Langmuir model is an essential index to evaluate the maximum adsorption capacity of the adsorbent, which was assumed to be irrelevant to the aqueous concentration of the adsorbate. Adsorption isotherms of cadmium onto soil and biochar were performed in the current study, and the regression Langmuir Qm was demonstrated to be highly dependent on the aqueous concentration. The regression Qm increased from 0.066 to 2.17 mg·g−1 (by ~3-fold) for the selected soil, and from 2.12 to 48.4 mg·g−1 (by ~23-fold) for the chosen biochar when the highest initial aqueous concentration increased from 2.34 to 887 mg·L−1. One inappropriate application for comparison of the regression Langmuir Qm as the adsorption capacity is found, i.e., it is difficult to directly compare the regression Qm without neither a saturated isotherm nor considering the experimental conditions. It is also very hard to accurately predict adsorption behavior by the regressed Langmuir model obtained from a partial adsorption isotherm. It is suggested to pay more attention to the difference between the saturated adsorption capacity and the regression Qm value derived from one unsaturated isotherm.
The fabrication of a nanostructure with a size of hundreds of nanometers down to sub-20 nm is investigated and demonstrated by e-beam lithography (EBL). The proximity effect influenced by the ...exposure dose during EBL is explored and analyzed for both pillar and grating patterns with positive and negative photoresist. By good control of the proximity effect and etching process, grating patterns from hundreds of nanometers down to about 20 nm are obtained. Furthermore, a pillar structure with a size down to sub-20 nm is achieved by annealing treatment of the photoresist hydrogen silsesquioxane at 400 °C without any further etching process. These nanostructures show great potential for efficiency enhancement of organic light-emitting diodes (OLEDs). The finite element analysis demonstrates there is the possibility of enhancing the external quantum efficiency of OLEDs peaking at 510 nm by a factor of 1.4. Such a high enhancement factor can only be achieved with finely controlled nanostructures, indicating the importance of size control during nanofabrication.
Fine particulate matter (PM2.5) concentrations show high variations in different microenvironments indoors, which has considerable impact on risk management. However, the real‐time variations of ...PM2.5 exposure associated with per activity/microenvironment and intra‐variation among family members remain undefined. In this study, real‐time monitors were used to collect real‐time PM2.5 data in different microenvironments in 32 households in urban community of China. Peak concentrations of PM2.5 were found in kitchen. The parallel levels of PM2.5 household indoor and outdoor indicated the benefit of clean energies use. To validly assess the health risk of individuals, we proposed a novel method to estimate the real‐time exposure of all residents and firstly investigate the intra‐variation of PM2.5 exposure among family members. The member who is responsible for cooking in the family had the maximum PM2.5 exposure. The ratios among intraindividual variations demonstrated children usually had lower exposure compared to the adults as they stayed more time in lower polluted microenvironments such as living room and bedroom. The exposure intensity in living room was above 1.0 for most residents, indicating it is warranted to alleviate the air pollution in living room. This study firstly focused on the intra differences of PM2.5 exposure among family members and provided a new insight for indoor air pollution management. The results suggested when adopting measures to reduce exposure, the microenvironments pattern of each member should be taken into consideration. Future work is welcomed to move another big step on this issue to protect the human health.
The device based on PM6:Y6-eC6-HD achievesan outstandingpower conversion efficiency(PCE) of 16.00% with a high fill factor (FF) of 77.32%.
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•The device based on PM6:Y6-eC6-HD afforded ...a PCE of 16.00% and a high FF of 77.32%.•Y6-eC6-HD possessed a high solubility and could be dissolved in green solvent.•Side chain engineering could improve the device performance, especially the FF.
In recent years, the development of non-fullerene acceptor (NFA) has rapidly improved the power conversion efficiency (PCE) of organic solar cells (OSCs). However, there are still many factors restricting the further improvement of PCE, and the low fill factor (FF) value is one of the main reasons. Therefore, it is of great importance to increase FF through designing organic semiconducting materials. In this paper, Y6-eC6-HD is obtained by modifying two kinds of alkyl chains of Y6, because the regulation of the side alkyl chains as one of the effective methods can get proper film morphology which is beneficial for balanced charge transfer and improved FF. Subsequently, the device based on PM6:Y6-eC6-HD can achieve an outstanding PCE of 16.00% with a high FF of 77.32%. Such a high fill factor is higher than that of the most of Y-series molecules. These results indicate that adjusting the side alkyl chains of NFAs is a promising method to enhance the FF and therefore improving the PCE of OSCs.
Fine particulate matter (PM
) concentrations show high variations in different microenvironments indoors, which has considerable impact on risk management. However, the real-time variations of PM
...exposure associated with per activity/microenvironment and intra-variation among family members remain undefined. In this study, real-time monitors were used to collect real-time PM
data in different microenvironments in 32 households in urban community of China. Peak concentrations of PM
were found in kitchen. The parallel levels of PM
household indoor and outdoor indicated the benefit of clean energies use. To validly assess the health risk of individuals, we proposed a novel method to estimate the real-time exposure of all residents and firstly investigate the intra-variation of PM
exposure among family members. The member who is responsible for cooking in the family had the maximum PM
exposure. The ratios among intraindividual variations demonstrated children usually had lower exposure compared to the adults as they stayed more time in lower polluted microenvironments such as living room and bedroom. The exposure intensity in living room was above 1.0 for most residents, indicating it is warranted to alleviate the air pollution in living room. This study firstly focused on the intra differences of PM
exposure among family members and provided a new insight for indoor air pollution management. The results suggested when adopting measures to reduce exposure, the microenvironments pattern of each member should be taken into consideration. Future work is welcomed to move another big step on this issue to protect the human health.
Considering the big displacement and the big rotation, adopting multiple accurate techniques to describe the geometrical nonlinearity, a beam element with explicit algorithms was presented. In order ...to obtain the coordinate transform matrix, the finite rotation theory and the yoshida method were used to determine the node direction vectors and the element direction vectors respectively. Using the Co-Rotational method, the deformation of the beam was calculated. To overcome the convergence difficulty of implicit approach, the explicit algorithms was used. Compared with numerical result of commercial FE code ANSYS, the beam shows very good performance.
Efficient organic light‐emitting diodes (OLEDs) commonly comprise a multilayer stack including charge‐transport and charge‐ and exciton‐blocking layers, to confine charge recombination to the ...emissive layer. Here, a highly simplified single‐layer blue‐emitting OLED is demonstrated based on thermally activated delayed fluorescence with the emitting layer simply sandwiched between ohmic contacts consisting of a polymeric conducting anode and a metal cathode. The single‐layer OLED exhibits an external quantum efficiency of 27.7% with minor roll‐off at high brightness. The internal quantum efficiency approaches unity, demonstrating that highly simplified single‐layer OLEDs without confinement layers can achieve state‐of‐the‐art performance, while greatly reducing the complexity of the design, fabrication, and device analysis.
Efficient blue single‐layer organic light‐emitting diodes are demonstrated, achieving 27.7% external quantum efficiency, low roll‐off, and low operating voltages. The internal quantum efficiency approaches unity, demonstrating that highly simplified single‐layer OLEDs without confinement layers can achieve state‐of‐the‐art performance, while greatly reducing the complexity of the design, fabrication, and device analysis.
Abstract Particle size is a critical factor for improving photocatalytic reactivity of conjugated microporous polymers (CMPs) as mass transfer in the porous materials is often the rate‐limiting step. ...However, due to the synthetic challenge of controlling the size of CMPs, the impact of particle size is yet to be investigated. To address this problem, a simple and versatile dispersion polymerization route that can synthesize dispersible CMP nanoparticles with controlled size from 15 to 180 nm is proposed. Leveraging the precise control of the size, it is demonstrated that smaller CMP nanoparticles have dramatically higher photocatalytic reactivity in various organic transformations, achieving more than 1000% enhancement in the reaction rates by decreasing the size from 180 to 15 nm. The size‐dependent photocatalytic reactivity is further scrutinized using a kinetic model and transient absorption spectroscopy, revealing that only the initial 5 nm‐thick surface layer of CMP nanoparticles is involved in the photocatalytic reactions because of internal mass transfer limitations. This finding substantiates the potential of small CMP nanoparticles to efficiently use photo‐generated excitons and improve energy‐efficiency of numerous photocatalytic reactions.
AbstractThe standard dwelling unit (SDU) has been adopted to standardize dwelling units and to reuse them in residential design, especially in the floor-plan design of multifloor buildings. However, ...conventional attribute-based search methods fail to represent important features, such as topology and shape, making it difficult to fully utilize the previously obtained information. Because building information models (BIMs) are replacing drawings and documents in storing and managing SDUs, this paper proposes a multiaspect similarity evaluation method to provide a more comprehensive way to search SDUs in residential design. The proposed approach introduced six similarities and their corresponding evaluation methods from the aspects of attribute, topology, and shape. Furthermore, a combined similarity was proposed to combine different similarities to reflect designers’ search intentions. Finally, a database with 170 SDUs and a prototype design tool were developed and tested in two projects. The application showed that the proposed method is capable of evaluating the similarity of SDUs in a more comprehensive manner and increasing the efficiency and quality of the search for SDU alternatives in the residential design process.
