To coordinate the trade-off between the separation and permeation of the nanofiltration membrane for the separation of Mg2+/Li+, we regulated poly(ethyleneimine)/piperazine interface polymerization ...parameters to construct a positively/negatively charged ultrathin Janus nanofiltration membrane at a free aqueous–organic interface. At the optimized interfacial polymerization parameters, 0.03 wt % of piperazine reacted with trimethylbenzene chloride prior to poly(ethyleneimine), forming a primary polyamide layer with fewer defects or limiting large-scale defects of the polyamide layer. The controlled subsequent reaction of poly(ethyleneimine) and trimethylbenzene chloride results in a Janus nanofiltration membrane, with one side enriched with the carboxyl groups, the other side enriched with the amine groups, and a dense polyamide structure in the middle. Under the optimum conditions, the positive potential of the rear surface of the prepared membrane was 14.57 mV, and the water contact angle reached 71.31°, while the negative potential of the front surface was −25.48 mV, and the water contact angle was 12.93°, confirming a Janus membrane with opposite charges and large hydrophilicity differences in the front and rear surfaces. With a high cross-linking degree, a 40 nm thick polyamide layer is 29.09% more thinner than the traditional polyamide membrane. The ultrathin Janus nanofiltration membrane showed an excellent separation factor (S Li,Mg of 18.26), stability, and water permeability flux (10.6 L·m–2·h–1·bar–1). The rejections to MgCl2, CaCl2, MgSO4, and Na2SO4 are measured above 90% at a nearly constant permeability of 10.6 L·m–2·h–1·bar–1, particularly stable rejections to MgCl2 and Na2SO4.
PurposeThe purpose of this paper is to propose a consensus method for multi-attribute group decision-making (MAGDM) problems based on preference-approval structure and regret theory, which can ...improve the efficiency of decision-making and promote the consensus level among individuals.Design/methodology/approachFirst, a new method to obtain the reference points based on regret theory and expert weighting method is proposed. Second, a consensus reaching method based on preference-approval structure is proposed. Then, an adjustment mechanism to further improve the consensus level between individuals is designed. Finally, an example of the assessment of elderly care institutions is used to illustrate the feasibility and effectiveness of the proposed method.FindingsThe feasibility and validity of the proposed method are verified by comparing with the advanced two-stage minimum adjustment method. The compared results show that the proposed method is more consistent with the actual situation.Research limitations/implicationsThis paper presents a consensus reaching method for MAGDM based on preference-approval structure, which considers the avoidance behaviors of individuals and reference points. Decision makers (DMs) can use this approach to rank and categorize alternatives while further increasing the level of consensus among them. This can further help determine the optimal alternative more efficiently.Originality/valueA new MAGDM problem based on the combination of regret theory and individual reference points is proposed. Besides, a new method of obtaining experts' weights and a consensus reaching method for MAGDM based on preference-approval structure are designed.
Nebkhas, a unique type of biogeomorphological aeolian landforms formed by sand accumulation around plants, are widely distributed in arid and semi-arid regions globally. Previous studies have ...highlighted the potential of nebkha sediments as valuable archives for understanding past climate and environmental changes. However, establishing a reliable chronological framework for nebkha sediments has posed challenges due to the lack of suitable dating methods. In this study, we applied both the quartz OSL and K-feldspar pIRIR150 protocols to date nebkha sediments from three different sites within the Mu Us dune field in north-central China. Internal checks indicate that the quartz OSL protocol is suitable for equivalent dose measurements, though age determinations for some quartz samples with weak luminescence signals may be subject to uncertainties. K-feldspar exhibits brighter signal intensity and a higher signal-to-noise ratio, making K-feldspar pIRIR150 ages reliable, particularly when residual doses are low, luminescence signals are stable, and dose recovery ratios are satisfactory. The results indicate that the luminescence ages derived from both the quartz OSL and K-feldspar pIRIR150 protocols are comparable, and these ages align with stratigraphic sequences and independent 137Cs dating results. Based on the established chronologies, our findings suggest that some large nebkhas in the southwestern Mu Us dune field likely originated 100–200 years ago, possibly in response to either climate-driven or human-induced aridification in this region.
•Luminescence dating methods were utilized to date relatively young nebkha sediments.•Internal checks on the quartz OSL and K-feldspar pIRIR150 protocols were conducted to assess the reliability and suitability.•Luminescence ages of the nebkha sediments align with the ages determined using radionuclide Caesium-137 dating.•The nebkhas in the southwestern Mu Us dune field likely originated approximately 100–200 years ago.
3D object detection, as an essential part of perception, plays a principal role in the autonomous driving system. The cost-competitive monocular 3D object detection has drawn increasing attention ...recently. However, it still suffers an inferior accuracy especially for occluded objects due to the limited camera view. Inspired by compositional models, in which an object is represented as a combination of multiple components, this paper proposes a new monocular 3D object detection method that decreases the impact of occlusion by utilizing an object’s front and side cues. To do this, the features are extracted from a decoupled front and side representation and then fused by an attention-based module to obtain a more consistent feature distribution. An uncertainty-guided depth ensemble based on geometry is further applied to refine the depth prediction. Experiment results demonstrate that as compared to the conventional methods, the proposed method significantly improves the detection performance for occluded objects while still satisfying real-time efficiency, with the Average Precision on 40 recall positions (AP40), respectively, increasing by 10.23% for partly occluded objects and 12.22% for mostly occluded objects in the KITTI benchmark. The codes are released at
https://github.com/kagurua/Front-Side-Det
This article shows how underdeveloped financial markets in emerging economies can explain the pattern of two-way capital flows between emerging economies (such as China) and the developed world (such ...as the United States). Our calibrated model reproduces China's rising financial capital outflows and FDI inflows as well as its massive trade imbalances in recent decades. Our model also predicts that global trade imbalances may be sustainable even in the long run and the conventional wisdom that the 'saving glut' of emerging economies is responsible for the global low interest rate may be wrong.
•3D gradient pore size structure effectively optimizes impedance matching.•The internal mesoporous structure enhances the multiple reflection loss.•TiO2-Ti3C2Tx realized the synergistic effect of ...dielectric loss and dipole loss.•TiO2-Ti3C2Tx/rGO/PDMS composites has ultra-high EMI SE and electric/photo-thermal conversion effect.
In this paper, the Ti3C2Tx/GO frame with vertical pore gradient is constructed by using 3D printing technology. The TiO2-Ti3C2Tx heterojunctions is generated in situ by thermal annealing to control the oxidation of 3D frames. TiO2-Ti3C2Tx/rGO/PDMS composites with high EMI SE and excellent thermal management performance are assembled by curing the annealed 3D frame with polydimethylsiloxane (PDMS). Notably, the composites have a unique multilayer-scale structure that rod-shaped TiO2 particles are decorated on Ti3C2Tx substrate and TiO2-Ti3C2Tx/rGO stack to form an amorphous porous gradient pore size structure. The effect of gradient pore size on EMI SE of composites is studied by simulation. Under the synergistic effect of multiple loss mechanism, the designed composites show conductivity of up to 173.1 S/m, the thickness of the composite is 2 mm and the density is 67 mg/cm3, which shows excellent EMI SE of 58 dB. The composites also have excellent thermal management performance.
As an effective way to obtain freshwater resources, atmospheric water harvesting (AWH) technology has been a wide concern of researchers. Therefore, hydrogels gradually become key materials for ...atmospheric water harvesters due to their high specific surface area and three-dimensional porous structure. Here, we construct a core–shell hydrogel-based atmospheric water harvesting material consisting of a shell sodium polyacrylate (PAAS) hydrogel with an open pore structure and a core thermosensitive poly N-isopropylacrylamide (PNIPAAm) hydrogel with a large pore size. Theoretically, the mutual synergistic hygroscopic effect between the core layer and the shell layer accelerates the capture, transport, and storage of moisture to achieve continuous and high-capacity moisture adsorption. Simultaneously, the integration of polydopamine (PDA) with the hydrogel realizes solar-driven photothermal evaporation. Therefore, the prepared core–shell hydrogel material possesses great advantages in water adsorption capacity and water desorption capacity with an adsorption of 2.76 g g–1 (90% RH) and a desorption of 1.42 kg m–2 h–1. Additionally, the core–shell structure hydrogel collects 1.31 g g–1 day–1 of fresh water in outdoor experiments, which verifies that this core–shell hydrogel with integrated photothermal properties can capture moisture in a wide range of humidity without any external energy consumption, can further sustainably obtain fresh water in remote water-shortage areas.
Atomic‐scale interface engineering is a prominent strategy to address the large volume expansions and sluggish redox kinetics for reinforcing K‐storage. Here, to accelerate charge transport and lower ...the activation energy, dual carbon‐modified interfacial regions are synthesized with high lattice‐matching degree, which is formed from a CoSe2/FeSe2 heterostructure coated onto hollow carbon fibers. State‐of‐the‐art characterization techniques and theoretical analysis, including ex‐situ soft X‐ray absorption spectroscopy, synchrotron X‐ray tomography, ultrasonic transmission mapping, and density functional theory, are conducted to probe local atomic structure evolution, mechanical degradation mechanisms, and ion/electron migration pathways. The results suggest that the heterostructure composed of the same crystal system and space group can sharply regulate the redox kinetics of transition metal selenium and dual carbon‐modified approach can tailor physicochemical degradation. Overall, this work presents the design of a stable heterojunction synergistic superior hollow carbon substrate, inspiring a pathway of interface engineering strategy toward high‐performance electrode.
Atomic‐scale interface engineering is a prominent strategy to address the large volume expansions and sluggish redox kinetics for reinforcing K‐storage. The heterostructure composed of the same crystal system and space group can sharply regulate the redox kinetics of transition metal selenium and dual carbon‐modified approach can tailor physicochemical degradation.
Graphdiyne (GDY), a new carbon allotrope, is composed of two types of hybridized (sp and sp2) carbon atoms to form a 2D planar network structure. After being synthesized in 2010, pristine GDY has ...attracted the attention of researchers, because of its large π-conjugated structure and excellent electronic properties. In recent years, there have been many reviews on GDY, but most reviews only briefly describe its synthesis and applications. Due to experimental limitations, it is difficult to gain insight into the electronic structure of GDY concerning its properties and applications. At the same time, there is also a lack of a thorough understanding of the application mechanism of GDY and GDY-based materials. By utilizing theoretical computation, not only the above problems can be solved but also experimental results can be predicted. Thus, in this paper, we review some of the physical properties of GDY-based materials from the perspective of theoretical calculations. Then, their theoretical prediction in the fields of energy storage and conversion is introduced, which points out the research direction and provides a theoretical basis for the experiments. It is hoped that this Review will play a positive part in developing GDY and its related calculations.
Environmental risks accumulate in cities, including polluted air and health disparities, but these risks can be reduced through scientific city planning. The purpose of this study was to investigate ...the global burden of premature mortality attributable to NO2 exposure in urban areas and the role of the built environment in this regard.
An approach based on health impact assessment was used to estimate the premature mortality burdens associated with NO2 exposure in 13,169 urban areas around the world using globally gridded NO2 and population estimates, baseline mortality, and epidemiologically derived exposure-response functions. We used the most recent WHO recommended value (i.e.,10 μg/m3) as a counterfactual concentration. Finally, the relationship between the characteristics of the built environment at the city level and the burden of NO2-related mortality was evaluated.
Worldwide, 549,715(95%CI: 276204–815,023) cases of death attributable to NO2 exposure in urban areas could be prevented if compliance with the latest WHO guideline, accounting for 2.7 % (95%CI:1.4 %–4.0 %) of total mortalities in 2019. Across cities around the world, the age-standardized mortality rate (per 100,000 people) attributable to NO2 exposure ranged from 51.3 (95%CI:25.8–76.0) in Central Asia to 3.4(95%CI: 1.7–5.1) in Oceania. Although there was a significant decrease in premature mortality attributable to NO2 exposure globally, considerable regional heterogeneity exists, with cities in Central Asia and Andean Latin America in particular exhibiting an upward trend. Further, we discovered a positive association between population density and street connectivity with mortality attributable to NO2. While the increase in green and blue space were significantly associated with a lower NO2-associated mortality.
The findings of this study provided a comprehensive understanding of the premature mortality burden due to NO2 in cities throughout the world and the role that urban planning policies can play in reducing the health burden associated with air pollution.
Display omitted
•Worldwide, 549,715 deaths attributable to NO2 in cities were estimated.•Negative associations between urban green and blue space with NO2-associated mortality were observed.•The positive effects of population density on urban NO2-associated mortality differed by city size.
