Bleaching and dyeing of superfine wool powder/polypropylene blend film

Fibers based regenerated protein draw much attention for recycling discarded protein resources and can produce biodegradable and environmental friendly polymers. In this study, superfine wool powder is blended with polypropylene (PP) to produce wool powder/PP blend film through extrusion and hot-pressing. Hydrogen peroxide is used to bleach the black colored surface of the blend films. The effects of peroxide concentration, bleaching time and powder content on the final whiteness and mechanical properties of the blend films are investigated.The bleached films are dyed with acid red dyes and the dyed color is evaluated using a Computer Color Matching System. Color characters of dyed films, such as L*, a*, b*, &Delta;E*ab, C*ab and K/S values are measured and analyzed. The study not only reuses discarded wool resources into organic powder, widens the application of superfine wool powder on polymers, but also improves the dyeing properties of PP through the addition of protein content.<br /

Effects of Rhizosphere NaCl Concentration on Morphology and Physiology of Mesembryanthemum crystallinum L.

【Objective】This study aimed to investigate the effects of rhizospheric NaCl concentration on the morphology and physiology of Mesembryanthemum crystallinum L. and determine the suitable NaCl concentration for it's hydroponic cultivation in plant factories, providing references for production management.【Method】Crystal M. crystallinum L. seeds were used as material, and the Japanese garden general formula was selected for cultivation in nutrient solution under artificial light. With no NaCl added as the control (CK), NaCl was added to the final concentration of 3 g/L (T1), 6 g/L (T2), 9 g/L (T3), 12 g/L (T4), respectively. After 21 days of NaCl treatment, the morphological and physiological indicators were analyzed, and the proportion of epidermal salt vacuole area and the number of epidermal salt vacuoles were counted, so as to analyze the relationship between NaCl concentration and the morphology and physiology of M. crystallinum L..【Result】From the perspective of morphological indicators and biomass, there were no significant differences in plant height, stem thickness, leaf area, root fresh weight and shoot fresh weight compared to the CK when M. crystallinum L. was grown in a nutrient solution with a NaCl concentration of 3 g/L. In the nutrient solution with a NaCl concentration of 6 g/L, M. crystallinum L. showed significantly increased in plant height, root fresh weight and shoot fresh weight compared to the CK, indicating a certain promotion effect on the growth of M. crystallinum L.. However, in the nutrient solutions with NaCl concentrations of 9 g/L and 12 g/L, M. crystallinum L. exhibited a decreasing trend in plant height, stem thickness, leaf area, and shoot fresh weight with significant differences compared to the CK. This suggests that the growth of M. crystallinum L. is inhibited in nutrient solutions with NaCl concentrations of 9 g/L and 12 g/L. In terms of physiological indicators, the protein content, soluble sugar content, and chlorophyll SPAD value of M. crystallinum L. increased with increasing NaCl concentration, reaching the highest levels in the nutrient solution with a NaCl concentration of 12 g/L, with increases of 50.2%, 119.5%, and 77.9% compared to the CK, respectively. Regarding the epidermal salt vacuole indicators, both the proportion of epidermal salt vacuole area and the number of epidermal salt vacuoles increased with increasing NaCl concentration, reaching the maximum values in the nutrient solution with a NaCl concentration of 12 g/L, with increases of 54.9% and 182.1% compared to the CK, respectively.【Conclusion】The optimal NaCl concentration for hydroponic cultivation of M. crystallinum L. in plant factories falls within the range of 3-6 g/L

Pumpkin-like MoP-MoS2@Aspergillus niger spore-derived N-doped carbon heterostructure for enhanced potassium storage

Biomass-derived carbon materials are widely applied in the energy storage and conversion fields due to their rich sources, low price and environmental friendliness. Herein, a unique pumpkin-like MoP-MoS2@Aspergillus niger spore-derived N-doped carbon (SNC) composite has been prepared via a simple hydrothermal and subsequent phosphorization process. Interestingly, the resulting MoP-MoS2@SNC well inherits the pristine morphology of spore carbon, similar to the natural pumpkin, with hollow interiors and uneven protrusions on the surface. The special structure allows it to have sufficient space to fully contact the electrolyte and greatly reduces the ion transport distance. The theory calculations further demonstrate that the formed MoP-MoS2 heterostructure can enhance the adsorption of K ions and electronic couplings. With these unique advantages, the MoP-MoS2@SNC anode for potassium storage shows a high reversible capability of 286.2 mAh g−1 at 100 mA g−1 after 100 cycles and superior rate performance. The enhanced electrochemical performance is mainly related to the unique pumpkin-like morphology of SNC and the construction of MoP-MoS2 heterostructure, as well as their perfect coupling. This study provides a feasible design idea for developing green, low-cost, and high-performance electrode materials for next-generation energy storage.</p

Adina Rubella-Like Microsized SiO@N-Doped Carbon Grafted with N-Doped Carbon Nanotubes as Anodes for High-Performance Lithium Storage

Microsized silicon oxide (SiO) has become a highly potential anode material for practical lithium-ion batteries (LIBs) in virtue of its low cost and high capacity. However, its commercialization is still impeded by the low inherent conductivity and nonignorable volume expansion of SiO in the lithiation/delithiation processes. Herein, an in situ catalytic growth approach is developed for grafting N-doped bamboo-like carbon nanotubes (NCNTs) onto the polydopamine-coated SiO microparticles, yielding a unique adina rubella-like SiO@NC-NCNT composite. The cross-sectional scanning electron microscopy images reveal that the flexible middle-carbon layer plays a crucial role in alleviating volume expansions and improving structural stability of SiO@NC-NCNTs. Theoretical density functional theory simulation results further prove that the rational construction of ternary heterostructure can effectively balance lithium adsorption energies and greatly improve conductivity of SiO@NC-NCNTs. As a result, the as-fabricated SiO@NC-NCNTs LIB anode shows a high reversible specific capacity of 1103.7 mA h g−1 at 0.2 A g−1 after 200 cycles with a high retention of 99.6% and an outstanding rate capability of 569 mA h g−1 at 5000 mA g−1. The strategy developed herein demonstrates a feasible avenue for developing high-energy SiO-based anodes for LIBs.</p

Solubility of Ethyl <i>p</i>‑Aminobenzoate in Six Alcohols within (283.15 to 327.15) K

The solubility of ethyl <i>p</i>-aminobenzoate (EPAB) was measured in six different alcohols (methanol, ethanol, <i>n</i>-propanol, <i>n</i>-butanol, isobutyl alcohol, isoamyl alcohol) within (283.15 to 327.15) K by the last solid disappearance method. The solubility increases with increasing temperature. The decreasing order satisfies the following sequence: methanol > ethanol > <i>n</i>-propanol > <i>n</i>-butanol > isoamyl alcohol > isobutyl alcohol. Four models, including modified Apelblat equation, <i>λh</i> model, NRTL model, and Wilson model, were used to correlate the experimental data of EPAB. It is found that the modified Apelblat equation, NRTL model, and Wilson model were suitable to correlate the solubility of EPAB in the selected solvents with an overall RAD less than 2%. In addition, the changes of thermodynamic properties of solution [standard molar enthalpy (Δ_dis<i>H</i>^o), standard molar entropy (Δ_dis<i>S</i>^o), and standard molar Gibbs energy (Δ_dis<i>G</i>^o)] were obtained. The results indicate that the dissolution process of EPAB in these alcohols is endothermic and an entropy-driven process

Synthesis of Methyl Sorbate Catalyzed by Deep Eutectic Solvent Based on Choline Chloride: Kinetics and Optimization

The synthesis process and kinetics of the esterification of methanol with sorbic acid catalyzed by deep eutectic solvents (DESs) were explored in this study. A series of green DESs composed of choline chloride (ChCl) and p-toluene sulfonic acid monohydrate (PTSA) were successfully prepared. Design and optimization of the process were conducted using the response surface methodology with Box-Behnen design. The influences of the value of z (z is the molar ratio of PTSA to ChCl), catalyst loading, methanol/sorbic acid molar ratio, and temperature on the conversion of sorbic acid were evaluated. Using ChCl-1.38PTSA as a catalyst, the kinetic data and chemical equilibrium compositions of the esterification were measured at a temperature range of 340.15–355.15 K. The UNIFAC model was utilized to estimate the equilibrium constants, and the thermodynamic data (ΔrH0, ΔrS0, ΔrG0) of the esterification reaction were calculated as well. The pseudohomogeneous model based on activity was then adopted to describe the reaction kinetics and the model fitted well with the experimental data. The activation energy of the forward and reverse reaction were calculated. In addition, the activity of ChCl-1.38PTSA declined not obviously after five cycles, suggesting that ChCl-1.38PTSA has good stability and recyclability

Predicting acute onset of heart failure complicating acute coronary syndrome: an explainable machine learning approach

Patients with acute coronary syndrome (ACS) are at high risk of heart failure (HF). Early prediction and management of HF among ACS patients are essential to provide timely and cost-effective care. The aim of this study is to train and evaluate a machine learning model to predict the acute onset of HF subsequent to ACS. A total of 1,028 patients with ACS admitted to Guangdong Second Provincial General Hospital between October 2019 and May 2022 were included in this study. 128 clinical features were ranked using Shapley additive exPlanations (SHAP) values and the top 20% of features were selected for building a balanced random forest (BRF) model. We compared the discriminatory capability of BRF with linear logistic regression (LLR). In the hold-out test set, the BRF model predicted subsequent heart failure with areas under the curve (AUC) of 0.76 (95% CI: 0.75-0.77), sensitivity of 0.97 (95% CI: 0.96-0.97), positive predictive value (PPV) of 0.73 (95% CI: 0.72-0.74), negative predictive value (NPV) of 0.63 (95% CI: 0.60-0.66), and accuracy of 0.73 (95% CI: 0.72-0.73), respectively. BRF outperforms LLR by 15.6% in AUC, 3.0% in sensitivity, and 60.8% in NPV. End-to-end machine learning approaches can predict the acute onset of heart failure following ACS with high prediction accuracy. This proof-of-concept study has the potential to substantially advance the management of ACS patients by utilizing the machine learning model as a triage tool to automatically identify clinically significant patients allowing for prioritization of interventions. [Abstract copyright: Copyright © 2022. Published by Elsevier Inc.

An energy-free strategy to elevate anti-icing performance of superhydrophobic materials through interfacial airflow manipulation

Abstract Superhydrophobic surfaces demonstrate excellent anti-icing performance under static conditions. However, they show a marked decrease in icing time under real flight conditions. Here we develop an anti-icing strategy using ubiquitous wind field to improve the anti-icing efficiency of superhydrophobic surfaces during flight. We find that the icing mass on hierarchical superhydrophobic surface with a microstructure angle of 30° is at least 40% lower than that on the conventional superhydrophobic plate, which is attributed to the combined effects of microdroplet flow upwelling induced by interfacial airflow and microdroplet ejection driven by superhydrophobic characteristic. Meanwhile, the disordered arrangement of water molecules induced by the specific 30° angle also raises the energy barriers required for nucleation, resulting in an inhibition of the nucleation process. This strategy of microdroplet movement manipulation induced by interfacial airflow is expected to break through the anti-icing limitation of conventional superhydrophobic materials in service conditions and can further reduce the risk of icing on the aircraft surface

Co Nanoparticles Encapsulated in N-Doped Carbon Nanotubes Grafted CNTs as Electrocatalysts for Enhanced Oxygen Reduction Reaction

The exploration of high-efficiency and inexpensive electrocatalysts for oxygen reduction reaction (ORR) is of critical significance for renewable energy conversion. Herein, an in situ catalytic transformation strategy toward a unique hierarchical nanostructure is reported. In the architecture, Co nanoparticles encapsulated at the tip of bamboo-like N-doped carbon nanotubes (NCNTs) are grafted on N-doped polypyrrole-derived CNTs. Thanks to the smart design of unique 3D architecture, the NPCN@Co-NCNTs catalyst displays an extraordinary ORR activity in 0.1 m KOH solution (the onset and half-wave potentials are 0.96 and 0.90 V vs RHE, respectively), which is similar to commercial Pt/C catalyst (0.99 and 0.88 V vs RHE, respectively). Meanwhile, the catalyst shows the low Tafel slope of 78 mV dec−1 and long-time stability. Experimental and theoretical results verify that the improved ORR performance is mainly related to the existence of Co nanoparticles protected by pyridinic-N-doped carbon, which lowers the theoretical overpotential of ORR. Density functional theory calculations reveal that Pyridinic-NC-Co site is the reactive site with the lowest overpotential for ORR (0.57 V). These results unambiguously indicate that the NPCN@Co-NCNTs represent a low-cost yet high-efficiency electrocatalyst for the electrocatalytic ORR.</p

Cation-Exchange Resin Catalyzed Ketalization Reaction of Cyclohexanone with 1,4-Butanediol: Thermodynamics and Kinetics

The thermodynamics and kinetics for the ketalization reaction of cyclohexanone with 1,4-butanediol catalyzed by 732 cation-exchange resin were studied for the first time. The reaction equilibrium compositions were obtained from 293.15 to 333.15 K at atmospheric pressure, and the equilibrium constants was estimated using the UNIFAC model. The thermodynamic properties of the ketalization reaction were evaluated: Δ<i>H</i>⁰ = −12.85 kJ mol^–1, Δ<i>G</i>⁰ = −1.04 kJ mol^–1, Δ<i>S</i>⁰ = −39.61 J K^–1 mol^–1. The influences of various experimental parameters like agitation speed, initial molar ratio of reactants, temperature, catalyst loading, and particle size on the conversion of limiting reactant were studied. Different kinetic models were tested against the experimentally measured kinetic data and the results show that the Eley–Rideal model with chemisorption of 1,4-butanediol on the active sites predict the kinetics best. The <i>E</i>_a value for the overall ketalization reaction is found to be 43.89 kJ mol^–1