Chelating Metal Ions in a Metal-Organic Framework for Constructing a Biomimetic Catalyst Through Post-modification

Crystal engineering, as a burgeoning technology, has been widely used to construct metalloporphyrins biomimetic catalysts. Herein, a bimetallic metal-organic framework (MOF) was constructed by 4-(4-carboxyphenyl)-1,2,4-triazole ligand, Co²⁺ and Zr⁴⁺ metal ions by solvothermal reaction(named PFC-88). A N,N-chelation site was found between the two adjacent ligands in PFC-88, consequently a porphyrin-like structure was obtained through chelating Fe³⁺ in this site by post-modification, named PFC-88-Fe. The result of a single crystal X-ray technology verified that Fe ions were successfully metalated in the N,N-chelation site of PFC-88, which is assisted by the X-ray absorption near-edge structure(XANES) spectra. An o-phenylenediamine oxidation reaction was applied to assessing the catalytic activity of PFC-88-Fe, in which the absorbance increases of phenazine-2,3-diamine at λ=418 nm were recorded by absorption spectroscopy in kinetic mode, exhibiting the application potential as a biomimetic catalyst.     

Asymptotic Behavior of Least Energy Solutions for a Fractional Laplacian Eigenvalue Problem on ℝN

Acta Mathematica Sinica, English Series - We are interested in the existence and asymptotic behavior for the least energy solutions of the following fractional eigenvalue problem $$\left({\rm{P}}...     

陶瓷基功能材料载体纤维增强效果及机理

以陶瓷基功能材料载体为研究对象,按照其生产工艺配方,研究了纤维种类(莫来石、氧化铝、氧化锆)及其添加量对陶瓷基功能材料载体性能的影响.在相同实验条件且不影响其功能化参数前提下,将其与未添加纤维的空白试样力学性能进行对比.结果表明,试样经1200℃烧成后,相比莫来石与氧化铝纤维增强的陶瓷基功能材料载体,氧化锆纤维的增强效果最好.当氧化锆纤维的添加量为0.8 wt;时,试样的吸水率和气孔率均较低,分别为2.0;、4.0;,相比空白对比试样抗折强度增强了42.4;.     

A novel PCR-based technology for rapid and non-sequencing authentication of Bombyx batryticatus using species-specific primers

A novel PCR technology was developed to detect short DNA fragments using species-specific primers for rapid and non-sequencing authentication of Bombyx batryticatus based on differences in the mitochondrial genome. Three specifically designed primer reactions were established to target species for the reliable identification of their commercial products. They were confirmed to have a high inter-species specificity and intra-species stability. The limit of detection was estimated as 1 ng of genomes for Beauveria bassiana and 100 pg for Bombyx mori and Metarhizium anisopliae. Furthermore, validation results demonstrated that raw materials and their processed products can be conveniently authenticated with good sensitivity and precision using this newly proposed approach. In particular, when counterfeits were assayed, these primer sets performed well, whereas COI barcoding technology did not. These could also assist in the discrimination and identification of adulterates of other animal-derived medicines in their pulverized and processed forms and even in complexes.     

Nickel Oxide/Graphene Composites: Synthesis and Applications

Nickel oxide (NiO) has emerged as one of the most promising transition-metal oxides (TMOs) for electrochemical capacitors, batteries, catalysis, and electrochromic films, owing to its cost-effectiveness, abundance, and well-defined electrochemical properties. Recent studies have identified that mixing NiO with graphene or graphene derivatives results in novel composites with synergistic effects and superior electrochemical performance. This review summarizes the latest advances in composites of NiO with graphene or graphene derivatives. The synthetic strategies, morphologies, and electrochemical performance of these composites are introduced, as well as their electrochemical applications in supercapacitors, batteries, sensors, catalysis, and so forth. Finally, tentative conclusions and assessments regarding the opportunities and challenges for the future development of these composites and other TMOs/graphene or graphene-derived composites are presented.     

化学法改性煤沥青脱除苯并芘的研究

在管式反应器中采用苯甲酸、聚乙二醇、固体古马隆树脂（S）、液体古马隆树脂（L）为添加剂来降低煤沥青中有害物质苯并芘的含量，以期使得煤沥青可绿色化应用。采用紫外-可见分光光度计分析煤沥青中苯并芘含量。考察了反应温度、反应时间、添加剂添加量、催化剂等工艺条件对添加剂脱除煤沥青中苯并芘的影响。结果表明，不同工艺条件能降低煤沥青中苯并芘的含量。在优化条件下，不同添加剂对苯并芘脱除率由高到低依次为：液体古马隆树脂、聚乙二醇、苯甲酸和固体古马隆树脂。分析其反应机理，这与催化剂的酸性相关，发生亲电取代反应。结果表明，液体古马隆树脂（L）在催化剂存在下对煤沥青中苯并芘脱除率可达73.0%，显示了良好的应用前景。     

Optical Radiation Associated with Photobiological Hazards for Argon GTAW Arcs

Plasma Chemistry and Plasma Processing - Gas tungsten arc welding (GTAW), a widely used industrial process, is one of the most intense artificial sources of optical radiation. This paper presents a...     

Stable isotope dilution assay for the accurate determination of tricaine in fish samples by HPLC–MS–MS

Tricaine methanesulfonate is one of most commonly used anesthetics in fish during blood sampling, artificial propagation and long‐distance transportation. In this study, an accurate method for the quantitative determination of tricaine in fish samples by a stable isotope dilution assay coupled with high‐performance liquid chromatography–triple quadrupole mass spectrometry was developed. Tricaine‐D₅ was synthesized and used as an isotopically labeled internal standard for the determination of tricaine. The analytical performance of the method was validated for tricaine determination in marine fish and freshwater fish. The determination of tricaine was linear in the range of 2.0–200.0 μg L^?1. The limit of detection and limit of quantitation for fish muscle tissues were 1.0 and 4.0 μg kg^?1, respectively. Good recoveries were obtained in the range of 92.08–97.50%. The inter‐ and intra‐assay relative standard deviations (RSD values) were investigated, and the values were 0.39–3.01 and 0.85–2.77%, respectively. The values of CCα and CCβ were 10.21–10.43 and 10.42–10.87 μg kg^?1, respectively. The clearance of MS‐222 from grass carp was further studied using our method. The results demonstrate that MS‐222 could be well absorbed and rapidly eliminated after bath administration.     

Mg/Cd共掺杂ZnO电子结构与光学性质的第一性原理研究

采用基于密度泛函理论的第一性原理平面波超软赝势法,研究了Mg/Cd(不同的Cd浓度)共掺杂ZnO的电子结构和光学性质.研究表明:Mg/Cd共掺杂ZnO,体系的晶胞尺寸变大,但结构稳定.当Mg/Cd为1:1时,吸收边略微发生蓝移.随Cd的掺杂浓度增加,导带部分逐渐下移,禁带宽度变窄,出现红移现象.除此之外体系的吸收率和反射率也减小.说明Mg/Cd共掺杂ZnO,不仅使得体系光学谱丰富,而且透射性增强.这对实验中制备出高透射率的材料具有一定的指导意义.