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The large-scale application of phenolic aerogel is limited by its complex and lengthy production process as well as its expensive cost. Herein a simultaneous drying-curing method for phenolic aerogels was designed based on the sol–gel process, and a series of phenolic aerogels with different hexamethylenetetramine (HMTA) contents were prepared. The material parameters such as microstructure, pore structure, mechanical properties, shrinkage, and density of the aerogel were characterized. The results show that compared with the conventional full-sealing method, the simultaneous drying-curing method shortens the preparation time of aerogels by nearly half and improves the safety of the preparation process. The prepared phenolic aerogels still maintain the nanoporous microscopic morphology. When the HMTA content is 1/6 of the phenolic mass, the linear shrinkage rates of the aerogels prepared by this method and the conventional full-sealing method are 9.8 and 9.4%, respectively. The densities are 0.25 and 0.22 g·cm , and the BET specific surface areas are 54.42 and 54.31 m ·g , and the compressive yield strengths are 1.76 and 1.16 MPa. At the same time, the thermal conductivity of the phenolic aerogels prepared by the simultaneous drying-curing method is less than 0.06 W·(m·K) at room temperature. These results indicate that the properties of the aerogels prepared by the simultaneous drying-curing method are close to those prepared by the conventional method, which proves that this method has guiding significance for the large-scale, low-cost, and rapid production of nanoporous phenolic aerogels.

Background Multimorbidity is common in older adults and associated with poor outcomes. Evidence for a nonlinear relationship between hemoglobin (Hb) levels and multimorbidity risk remains limited, particularly in large-scale studies. This study examines the dose-response relationship between Hb and cardiometabolic multimorbidity (CMM) to inform early risk assessment. Methods This cross-sectional study analyzed data from the National Primary Public Health Service System (NPPHSS) in Hainan Province, China, including 466,751 adults aged ≥ 65 years. Key variables included Hb levels, measured using the sodium lauryl sulfate method, and CMM (defined as the coexistence of ≥ 2 conditions among hypertension, diabetes, and hyperlipidemia). We used logistic regression and restricted cubic spline (RCS) models to assess the nonlinear dose-response relationship between Hb and CMM risk. Subgroup and sensitivity analyses were performed to assess the robustness of the findings. Results The mean age was 74.6 ± 6.9 years; 56.4% were female. CMM prevalence was 32.1%. Mean Hb was 132.9 ± 15.4 g/L. RCS analysis revealed a significant nonlinear relationship (P for non-linear < 0.001). Odds ratios (ORs) formed a U-shaped curve, decreasing to a nadir at 112 g/L (OR = 0.885, 95% CI: 0.868 - 0.902) and rising with higher Hb levels, exceeding 1.0 above approximately 132 g/L. Subgroup analyses by sex, age, BMI, and multimorbidity patterns confirmed consistent U-shaped associations. Especially, among participants with all three chronic conditions, Hb ≥ 132 g/L or ≤ 83 g/L was positively associated with multimorbidity, and a negative association was noted in the Hb range of 104 - 132 g/L. Conclusion Our findings demonstrate a significant U-shaped association between Hb levels and CMM in Chinese older adults. Maintaining Hb within a reasonable range may be a consideration for primary prevention strategies.

Analyzing and addressing the unmet medical needs (UMNs) of older adults is one of the key agendas for health systems to achieve the goals of universal health coverage. This study aims to investigate the distribution, determinants, and inequalities of UMNs among Chinese older adults. The data used from the 2023 National Health Service Survey in Hainan, with a sample of 4112 adults aged 60 and above. Chi-square tests and binary logistic regression were used to examined the factors associated with UMNs. Concentration indices and concentration curves to reflect the health inequalities in UMNs, and a decomposition approach was further employed to examine the contribution of each factor to these inequalities. 21.60% of the sample reported UMNs. Compared to the reference group, older adults who are of the Li ethnic group, had no personal income, did not participate in social activities, had no access to aging services, had a higher number of chronic diseases, and not physically independent had a higher likelihood of UMNs (P < 0.05). Additionally, socioeconomic-related health inequalities existed in the UMNs of the older adults, with a higher concentration among those with poorer economic condition, lower educational level, and those living in the western region (P < 0.01). The top three contributing factors to these inequalities were ethnicity (-47.03%), number of chronic diseases (-36.93%), and household per capita income (-25.36%). The UMNs of the older adults and the potential threat to inequalities require the attention of policymakers. Interventions should focus on improving access to medical services, with a particular emphasis on addressing the needs of vulnerable populations.

The composites were prepared by modifying silicon carbide fiber with particles of zirconium carbide (ZrC) and boron carbide (B 4 C) and incorporating them into a phenolic resin matrix. The influence of ZrC and B 4 C on the mechanical performance of SiC f /phenolic composites after high-temperature pyrolysis was studied through flexural performance test. The results show that the composite material has good thermal stability and high-temperature mechanical properties. After static ablation at 1 400 °C for 15 minutes, the flexural strength of the composite material reaches 286 MPa, which is still 7.3% higher than at room temperature, indicating that the composite material still has good mechanical properties even after heat treatment at 1 400 °C.

The electrocatalytic hydrogen evolution reaction (HER) of a given metal catalyst is intrinsically related to its electronic structure, which is difficult to alter for further improvement. Recently, it was discovered that the density of grain boundaries (GBs) is mechanistically of great importance for catalytic activity, implying that GBs are quantitatively correlated with the active sites in the HER. Here, by modeling the atomistic structure of GBs on a Au(110) surface, we find that HER performance is greatly enhanced by Au GBs, suggesting the feasibility of the HER mediated by GBs. The promoted HER performance is due to an increase in the capability of binding adsorbed hydrogen on the sites around GBs. A Au catalyst with a dominantly exposed (110) plane is synthesized, where considerable GBs exist for experimental verification. It is found that HER activity is inherently correlated with the density of the GBs in Au NPs. The improvement in HER activity can be elucidated from the geometrical and electronic points of view; the broken local spatial symmetry near a GB causes a decrease in the coordination numbers of the surface sites and the shift up of the d–band center, thereby reducing the limiting potential for each proton−electron transfer step. Our finding represents a promising means to further improve the HER activity of a catalyst.

Alloying is regarded as one of the most promising strategies for boosting performance of catalysts for hydrogen evolution reaction (HER) due to the adjustable electronic structure and intermediate adsorption. However, there is no theory (including d‐band center theory) can accurately guide the preparation and design of alloy catalysts, and thus resulting all the reported alloy catalysts are obtained by time‐consuming and laborious experimental exploration. Herein, we proposed a mean d‐band center (εas) as a new accurate descriptor for alloy activity prediction. Theoretical simulation and experiment results revealed that this descriptor exhibits a strong scaling relation with H adsorption energy. Besides, the obtained Cu–Ag alloy displays an optimal overpotential of 223 mV at 10 mA/cm2 in 0.5 mol/L H2SO4, which is more than 300 mV lower than those of pristine Cu (530 mV) and Ag (569 mV) powder. Our work provides a new idea toward designing highly efficient HER catalysts and broadens the applicability of d‐band theory to activity prediction of alloys. This study proposed a new descriptor (εas) to represent the d‐band center of hollow site in Cu–Ag alloys in different ratio and established a linear relationship between εas and H adsorption energy, which was verified via theoretical simulation and experiment results.

Sludge, a rapidly accumulating by‐product of wastewater treatment worldwide, holds great potential as an ideal coal substitute following dehydration and drying. Here, we present a solar‐powered heavy metal trap (SPHT) designed for sludge drying and concurrent electricity generation, validated using a PPy‐coated super hydrophilic wood (PPy‐H‐Wood). The SPHT in this work uniquely integrates sludge drying, heavy metal removal, and electricity generation characteristics. The indoor experiments demonstrate a rapid decrease in sludge water content from 90 % to 31 %, accompanied by an impressive 94 % reduction in free heavy metal content achieved through synergistic adsorption and evaporation. Harnessing the hydrovoltaic effect, the SPHT can generate an initial potential of 0.10 V. By monitoring this hydrovoltaic potential, the sludge drying process can be self‐detected. Furthermore, we have constructed a 20 m2 pilot‐scale SPHT device, achieving a sludge drying ratio of over 80 % and a heavy metal removal ratio exceeding 75 %. Life cycle assessment (LCA) indicates that replacing traditional heat drying technology with the SPHT can cut CO2 emissions by ∼98 %. Our work provides an eco‐friendly approach to sludge disposal and resource recovery, and may inspire more innovative solutions supportive of global Sustainable Development Goals. Herein, we propose a solar‐powered heavy metal trap (SPHT) for sludge disposal. The indoor experiments demonstrated that the sludge water content decreased from 90 % to 31 %, coupled with a decrease in heavy metal content to 6 % at most. Furthermore, the designed SPHT generated an initial potential of 0.10 V, and monitoring this hydrovoltaic potential enabled self‐detection of the sludge drying process.