The Comparative Study of Reaction Mechanisms and Catalytic Performances of Cu–SSZ-13 and Fe–SSZ-13 for the NH3-SCR Reaction

Catalysis Surveys from Asia - The catalytic performances and mechanism differences of model catalysts Cu–SSZ-13 and Fe–SSZ-13 with similar metal content and Si/Al ratio were compared....     

Neutral 1D Perovskite-Type ABX3 Phase Transition Material with a Narrowband Emission and Semiconductor Property

Cyclic organic amines are emerging as excellent building blocks to assemble organic–inorganic hybrid phase transition materials due to their flexible cyclic structure. Here, we have assembled a 1D organic-inorganic hybrid dielectric material C₅H₆NOPbBr₃ ( 1 ) by alloying the cyclic organic amine 3-hydroxypyridine. 1 displays a remarkable switchable dielectric response induced by an order-disorder transformation of the organic moiety, this transformation behaviour is confirmed by DSC and Hirshfeld surface measurements. More interestingly, 1 has a narrowband emission (FWHM=4.64 nm) at 590 nm; FWHM is a major quality figure for narrowband photodetectors. In addition, 1 exhibits semiconducting properties with an indirect bandgap of 2.78 eV by the analysis of the UV-Vis absorption results.     

Adatom Defect Induced Spin Polarization of Asymmetric Structures

The spin polarization of carbon nanomaterials is crucial to design spintronic devices. In this paper, the first-principles is used to study the electronic properties of two defect asymmetric structures, Cap-(9, 0)-Def [6, 6] and Cap-(9, 0)-Def [5, 6]. We found that the ground state of Cap-(9, 0)-Def [6, 6] is sextet and the ground state of Cap-(9, 0)-Def [5, 6] is quartet, and the former has a lower energy. In addition, compared with Cap-(9, 0) CNTs, the C adatom on C₃₀ causes spin polarization phenomenon and Cap-(9, 0)-Def [6, 6] has more spin electrons than Cap-(9, 0)-Def [5, 6] structure. Moreover, different adsorb defects reveal different electron accumulation. This finding shows that spin polarization of the asymmetric structure can be adjusted by introducing adatom defects.     

FeO(OH)@C-Catalyzed Selective Hydrazine Substitution of p-Nitro-Aryl Fluorides and their Application for the Synthesis of Phthalazinones

An efficient hydrazine substitution of p-nitro-aryl fluorides with hydrazine hydrates catalyzed by FeO(OH)@C nanoparticles is described. This hydrazine substitutions of p-nitro-aryl fluorides bearing electron-withdrawing groups proceeded efficiently with high yield and selectivity. Similarly, hydrogenations of p-nitro-aryl fluorides containing electron-donating groups also smoothly proceeded under mild conditions. Furthermore, with these prepared aryl hydrazines, some phthalazinones, interesting as potential structures for pharmaceuticals, have successfully been synthesized in high yields.     

Analysis of the acid and alkali resistance of superhydrophobic paper mulch

Agricultural paper mulch is an indispensable part of modern agriculture. It had the functions of heat preservation, moisture preservation, insect resistance, disease prevention, and weed growth inhibition. In order to extend the service life of the paper mulch, we use the solution immersion method to modify the surface of the paper mulch. A super-hydrophobic paper mulch is mainly prepared by using hydrophobic silica. The static contact angle of the super-hydrophobic paper mulch with water is 160.6°. The super-hydrophobic paper mulch samples were immersed in acid solution (pH?=?4.6 H₂SO₄) and alkaline solution (pH?=?8.5 NaOH). The main instruments are contact angle tester, tensile testing machine and high-speed camera. The hydrophobic properties, mechanical properties and rebound properties of the two kinds of paper mulches were compared. The results showed that the tensile strength and droplet bounce height of the superhydrophobic paper mulch decreased after being soaked in acid or alkaline solution for 48 h. The mass loss rate of paper mulch was more significant in acid solution, but its contact angle was still greater than 145°, and it had good bounce performance. After observing the microscopic morphology of its surface, it was found that silica had a micro-rough structure on the surface of the paper mulch. The method was simple and environmentally friendly, and can alleviate the problem of poor acid and alkali corrosion resistance of the paper mulch, and had extraordinary significance for environmental protection.

     

Dyeing behavior and mechanism of Crocein Orange G on carboxymethyl cotton fabric

Cellulose - Traditional cotton fiber dyeing requires an abundance of salt, which leads to environmental pollution. Consequently, decreasing or eliminating the use of salt has become the primary...     

Cationic and temperature-sensitive liposomes loaded with eugenol for the application to silk

Silk has been widely used in the clothing industry due to their soft and smooth features, good biocompatibility, good heat dissipation, warmth and ultraviolet resistance. The application of fragrance to silk can significantly improve the performance of silk. However, there are two key scientific problems that need to be solved: slowing down the release rate of fragrances and increasing the scent lasting time of silk. In this study, cationic and temperature-sensitive liposomes were designed and prepared to encapsulate eugenol. These fragrance-loaded liposomes significantly slowed down the release rate of the fragrance and controlled the release rate of the fragrance in a thermo-sensitive manner. The liposomes adhered to the silk through electrostatic adsorption interaction. The positive charge on the fragrance-loaded liposomes neutralized much negative charge on silk and thereby increasing the adhesion efficiency.     

Encapsulation of Phosphomolybdate Within Metal–Organic Frameworks with Dual Enzyme-like Activities for Colorimetric Detection of H2O2 and Ascorbic acid

Developing artificial enzyme mimetics for the detection of small biomolecules are a current research interest because natural enzymes bear some serious disadvantages, such as their catalytic activity can be easily inhibited and they can be digested by proteases. Herein, a heteropoly acids (HPA) encapsulating metal–organic framework (MOF) with metal-carbene structure, [Cu₁₀(H₃trz)₄(Htrz)₄][PMo₁₂VO₄₁] (PMA-MOF) as bifunctional enzyme-mimetic catalyst for colorimetric detection of hydrogen peroxide (H₂O₂) and ascorbic acid (AA) was designed and synthesized. Thanks to the good stability and the synergistic effect of PMA and MOF, PMA-MOF exhibits the lower limit of detection (0.222 μM towards H₂O₂ and 0.0046 μM to AA), and the smaller Km value (0.0138 mM for H₂O₂ and 0.136 mM for o-phenylenediamine) compared to most reported MOF- and HPA-based enzyme-mimetic catalyst, to the best our knowledge.

     

Formation and Structures of the μ4-Oxygen-Bridged High-Nuclearity Lead(II) Clusters from a Lead Propane-2-thiolate Complex

Journal of Cluster Science - Interaction of [Pb(SiPr)2]n with 1.5 equiv. of AgNO3 in DMF under aerobic conditions at room temperature gave a cationic lead-centered thiolate cluster...     

Thermal behaviors and kinetic analysis of two natural kaolinite samples selected from Qingshuihe region in Inner Mongolia in China

Journal of Thermal Analysis and Calorimetry - The thermal characteristic behaviors of two kaolinite samples selected from Qingshuihe region in Inner Mongolia in China were studied through...