Fire retarded polyurethane foam composites based on steel slag/ammonium polyphosphate system: A novel strategy for utilization of metallurgical solid waste

A series of FR-RPUF composites were prepared by a one-step water foaming process with ammonium polyphosphate (APP) and steel slag (SS) as flame retardants. Thermogravimetric analysis (TG), limiting oxygen index (LOI), UL-94 vertical combustion test, microscale combustion calorimetry (MCC), TG-Fourier transform infrared spectrometry (TG-FTIR), scanning electron microscopy (SEM), Raman spectra and FTIR were used to investigate the thermal stability, flame retardancy, combustion performance, gas phase products, and char residue morphology of FR-RPUF composites. TG test results showed that the initial decomposition temperature (T_-5wt%) and char residue rate at 700°C of RPUF/APP/SS composites were significantly enhanced by the addition of APP and SS, and the thermal stability of the composites was improved. Flame retardant test results confirmed the significantly increased LOI values of RPUF/APP/SS composites with V-0 rating. TG-FTIR also confirmed the obviously decreased release of toxic gases and flammable gases in the combustion of RPUF/APP/SS composites. SEM and Raman spectra of char residues for the composites suggested that APP/SS system improved the compactness and graphitization degree of char layer for RPUF/APP/SS composite. The above researches provide a new strategy for the utilization of SS in fire safety engineering.     

超高效液相色谱－四极杆－飞行时间质谱技术非靶向定性筛查猪肉中79种药物残留

利用超高效液相色谱－四极杆－飞行时间质谱（UPLC－Q－TOF MS）建立了猪肉中79种药物残留的非靶向定性筛查方法。猪肉样本采用0.5%（体积分数）甲酸－乙腈溶液先提取,甲醇后提取的组合提取方式,离心后上清液通过FAVEX－NM50兽药残留快速柱净化。以Acquity UPLC BEH HSS－C18色谱柱（2.1 mm × 150 mm,1.7 μm）进行分离,UPLC－Q－TOF MS电喷雾正离子模式电离,全信息串联质谱（MSE）模式检测。79种物质在相应范围内的线性关系良好,相关系数（r2）均不小于0.99,方法的检出限和定量下限分别为0.05 ~ 10 μg/kg和0.10 ~ 20 μg/kg。基于实验室自建质谱数据库,对模拟阳性样本以及市售猪肉样本进行筛查,同时使用高灵敏度Xevo TQ－S串联四极杆质谱多反应监测模式（MRM）对市售猪肉样本进行验证。结果表明,所建立的方法高效、快速、通量高,适用于猪肉中药物残留的筛查和鉴定。     

基于氮掺杂活性炭催化氧化合成氮甲基氧化吗啉的研究

以三聚氰胺为氮源,商用活性炭为研究对象,通过“浸渍吸附+高温热处理”的方式制得系列氮掺杂活性炭,并用于催化氧化合成氮甲基氧化吗啉（NMMO）。采用N₂吸附/脱附、Raman、XPS等对氮掺杂活性炭的孔结构和表面性质进行了表征。结果表明：随着三聚氰胺负载量的增大,氮掺杂活性炭的表面碱性含氮官能团含量增大,进而体现出更好的催化氧化合成NMMO活性。最佳催化剂（ACO850-20N）在催化剂加量为0.02 wt%,反应温度70 ℃和反应时间4 h的工艺条件下,氮甲基吗啉的转化率和NMMO收率可达99.76%和94.31%。      

新型氮杂环卡宾催化剂的合成及其在烯烃的自由基氟烷基酰化反应中的应用研究

以环庚酮及环己（庚）胺为起始原料,经溴代、环化、脱硫等反应,以良好的收率合成了环烷基取代的新型噻唑骨架的氮杂环卡宾催化剂。结果表明,在该催化剂催化下成功地实现了烯烃的自由基氟烷基酰化反应,以中等的收率完成了三种类型的γ-氟烷基取代酮的高效合成。所得化合物通过¹H NMR, ¹³C NMR, ¹⁹F NMR和HR-MS（ESI-TOF）进行表征。     

Convergent architecting of multifunction-in-one hydrogels as wound dressings for surgical anti-infections

Surgical procedures are susceptible to the cause of infections, which could induce delayed wound healing, oxidative stress and tissue ischemia. Multifunctional wound dressings (e.g., hydrogels) without the induction of antibiotics is promising for the elimination of surgical site infections and the associated complications. Herein, we report a reductionism approach for the fabrication of bioactive hydrogels to recapitulate antibacterial functions as well as antioxidant, pro-angiogenic and hemostatic properties in surgical infection treatments. The hydrogels composed of naturally derived Cirsium setosum extracts (CE, a traditional medicinal herb) and carboxymethyl chitosan (CS) show their capacity for surgical anti-infections on three different models (i.e., infectious random skin flap model, infectious skin defect model and infectious femur fracture model). Due to the innate bioactivities of CE and CS, CECS hydrogels can also reduce the bleeding loss (85% reduction) on a hemorrhaging liver model and improve the vascularization for skin flap regeneration. Overall, bioactive CECS hydrogels integrated with the ease and scalability of assembly process and biological activities without the addition of antibiotics is promising to act as multifunctional wound dressings for surgical anti-infections.     

Recent Progress in High-Performance Lithium Sulfur Batteries: The Emerging Strategies for Advanced Separators/Electrolytes Based on Nanomaterials and Corresponding Interfaces

Lithium-sulfur (Li−S) batteries, possessing excellent theoretical capacities, low cost and nontoxicity, are one of the most promising energy storage battery systems. However, poor conductivity of elemental S and the “shuttle effect” of lithium polysulfides hinder the commercialization of Li−S batteries. These problems are closely related to the interface problems between the cathodes, separators/electrolytes and anodes. The review focuses on interface issues for advanced separators/electrolytes based on nanomaterials in Li−S batteries. In the liquid electrolyte systems, electrolytes/separators and electrodes system can be decorated by nano materials coating for separators and electrospinning nanofiber separators. And, interface of anodes and electrolytes/separators can be modified by nano surface coating, nano composite metal lithium and lithium nano alloy, while the interface between cathodes and electrolytes/separators is designed by nano metal sulfide, nanocarbon-based and other nano materials. In all solid-state electrolyte systems, the focus is to increase the ionic conductivity of the solid electrolytes and reduce the resistance in the cathode/polymer electrolyte and Li/electrolyte interfaces through using nanomaterials. The basic mechanism of these interface problems and the corresponding electrochemical performance are discussed. Based on the most critical factors of the interfaces, we provide some insights on nanomaterials in high-performance liquid or state Li−S batteries in the future.     

SO2 Resisting Pd-doped Pr1-xCexMnO3 Perovskites for Efficient Denitration at Low Temperature

H₂-SCR is served as the promising technology for the controlling of NO_x emission, and the Pd-based derivative catalyst exhibited high NO_x reduction performance. Effectively regulating the electronic configuration of the active component is favorable to the rational optimization of noble Pd. In this work, a series of Pr_1-xCe_xMn_1-yPd_yO₃@Ni were successfully synthesized and exhibited superior NO conversion efficiency at low temperatures. 92.7 % conversion efficiency was achieved at 200 °C over Pr_0.9Ce_0.1Mn_0.9Pd_0.1O₃@Ni in the presence of 4 % O₂ with a GHSV of 32000 h⁻¹. Meanwhile, the outstanding performance was obtained in the resistance to SO₂ (200 ppm) and H₂O (8 %). Deduced from the results of XRD, Raman, XPS, and H₂-TPR, the modification of d orbit states in palladium was confirmed originating from the incorporation in the B site of Pr_0.9Ce_0.1Mn_0.9Pd_0.1O₃. The existence of higher valence (Pd³⁺ and Pd⁴⁺) than the bivalence in Pr_0.9Ce_0.1Mn_0.9Pd_0.1O₃ catalyst was evidenced by XPS analysis. Our research provides a new sight into the H₂-SCR through the higher utilization of Pd.     

Adsorption of Volatile Organic Compounds (VOCs) on Oxygen-rich Porous Carbon Materials Obtained from Glucose/Potassium Oxalate

To investigate the effects of oxygen-containing functional groups on the adsorption of volatile organic compounds (VOCs) with different polarity, oxygen-rich porous carbon materials (OPCs) were synthesized by heat treatment of glucose/potassium oxalate material. The carbon material had a large specific surface area (1697 m² g⁻¹) and a high oxygen content (18.95 at.%). OPC exhibited high adsorption capacity of toluene (309 mg g⁻¹) and methanol (447 mg g⁻¹). The specific surface area and total pore volume determined the adsorption capacity of toluene and methanol at the high-pressure range, while the oxygen-containing groups became the main factor affecting the methanol adsorption at the low-pressure range due to the hydrogen bond interaction through the density functional theory (DFT) calculations. This study provides an important hint for developing a novel O-doped adsorbent for the VOCs adsorption applications and analyzing the role of oxygen-containing groups in the VOCs adsorption under the low-pressure range.     

Copper-Catalyzed Synthesis of Axially Chiral Biaryls with Diaryliodonium Salts as Arylation Reagents

NOBIN and BINAM derivatives harboring biaryl frameworks are recognized as a class of important atropisomers with versatile applications. Here, we present an efficient synthetic route to access such compounds through copper-catalyzed domino arylation of N-arylhydroxylamines or N-arylhydrazines with diaryliodonium salts and [3,3]-sigmatropic rearrangement. This reaction features mild conditions, good substrate compatibility, and excellent efficiency. The practicality of this protocol was further extended by the synthesis of biaryl amino alcohols.     

Facile Synthesis of 2H-Benzo[h]Chromenes via an Arylamine-Catalyzed Mannich Cyclization Cascade Reaction

A simple arylamine-catalyzed Mannich-cyclization cascade reaction was developed for facile synthesis of substituted 2H-benzo[h]chromenes. The notable feature of the process included the efficient generation of ortho-quinone methides (o-QMs) catalyzed by a simple aniline. The mild reaction conditions allowed for a broad spectrum of 1- and 2-naphthols and trans-cinnamaldehydes to engage in the cascade sequence with high efficiency.