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Micro reactors are the essential part of thermal analysis techniques for characterizing gas-solid thermochemical reactions. The dynamic and diversified needs for investigating various complex materials and gas-solid reactions have led to the development of a variety of different microreactors over the years. Solid particles in microreactors are normally heated by furnaces from outside, resistive elements from inside, direct contact with bed particles, or other non-resistively methods. Solid particles can be fixed or fluidized in reactors where gas-solid contacts vary from diffusion-dominated to nearly diffusion-free conditions. Based on these characteristics, in this article we presented a broad classification for microreactors used for thermal analysis of gas-solid reactions. For each of the most popularly used microreactors, their features and limitations are briefly reviewed. By addressing the diversity of the microreactors used in the field of thermal analysis, the review aims at providing general guidance for the selection and operation of the microreactor to satisfy one's practical specific needs.

The massive stacking of the coal gangue (CG) in the coal mining process, discarded industrial zeolite waste (IZW) and agricultural corn straw (CS) has caused serious environmental pollution and resource waste. To achieve the recycling of solid waste, an economical method for synthesizing ultramarine blue pigment using a two-step calcination process of the CG/IZW/Na₂CO₃/S/CS with the mass rates of 1.50: 0.50: 2.50: 3.50: 1.00 (the first stage at 400°C for 0.50 h and the second stage at 900°C for 2.00 h) is proposed in this paper. The structure and composition of the synthesis ultramarine blue pigment were characterized by XRD, FT-IR, Raman, as well as SEM technologies, and results showed it had a sodalite structure containing S₃⁻ and S₂⁻ radicals. Furthermore, SiO₂ (1.20 mL of tetraethyl orthosilicate (TEOS) as the precursor and 4.50 mL of NH₃•H₂O as the catalyst) coated the synthesis ultramarine blue pigment (1.00 g) was successfully synthesized by sol-gel technique to improve the acid resistance of the pigment (pH=2.50-3.00). This new method of preparing ultramarine blue pigments not only achieves resource reuse at a low cost but also improves the acid rain resistance of the pigments.

Controllable synthesis of luminescent metal-organic frameworks (MOFs) having the merits of ease preparation, outstanding sensitivity and stability is of great significance for exploring their efficient sensing applications. Herein, we report a hierarchical terbium-doped yttrium-benzene-1,3,5-tricarboxylate MOF nanosheet via solvent-free synthetic strategy with a topological structure of MIL-78. The fluorescence property of the hierarchical Tb³⁺-doped Y-based MOF nanosheets can be tuned by adjusting the molar ratio of Tb³⁺ to Y³⁺ ions, and the Tb_0.5Y_0.5-MOF nanosheet-like morphology with the optimum characteristic Tb³⁺ ion green emission exhibited great potential acting as fluorescence probe for highly sensitive Fe³⁺ and Cr₂O₇²⁻ detection. The Tb³⁺-doped Y-MOF nanosheets show a fast response time of less than 1 s for Fe³⁺ ions. They also have low detection limits of 0.40 and 0.26 µM toward Fe³⁺ and Cr₂O₇²⁻ ions, respectively, as well as excellent stability. This work paves the way to explore intriguing hierarchical MOF-based luminescent materials for efficient fluorescence sensing applications.

Combining nanomaterials and waterborne resins is an effective way to obtain high-performance waterborne coatings. This paper provides a comprehensive overview on waterborne nanocomposite coatings based on the latest research progress at home and abroad. Specifically, the characteristics of zero-dimensional (0D), one-dimensional (1D), two-dimensional (2D) and binary hybrid (0D/1D, 0D/2D, 1D/2D, 2D/2D) nanomaterials and their applications in waterborne coatings are coherently reviewed. Subsequently, various modification methods of nanomaterials, especially noncovalent modification and covalent modification, are analyzed in detail. Additionally, the enhancement mechanisms of nanomaterials enhancing the corrosion resistance of waterborne nanocomposite coatings are also discussed, including physical barrier mechanism and electrochemical mechanism. Finally, based on the above discussion, the outlooks for the future design of waterborne nanocomposite coating are presented.

Fast pyrolysis of biomass is an attractive way to produce bio-oil since it can convert most of biomass components directly into liquid fuel. However, the bio-oils obtained from such a fast pyrolysis process always have highly complex oxygenated compounds with high viscosity, serious corrosivity, and rather instability. Thus, before the raw bio-oils are used as fuel or chemical feedstock, they must be upgraded, especially deoxygenated. Cracking of bio-oils over porous solid catalysts such as zeolite-based catalysts at ambient pressure is considered one of effective ways for the bio-oil upgrading, especially in which hydrogen gas is not necessary. Herein, zeolite-based catalysts (mainly HZSM-5 based catalysts) for the upgrading of pyrolysis bio-oils are critically reviewed. The effects of porous structure, acidity and other parameters including biomass type, biomass/catalyst ratio and operation temperature on cracking activity, selectivity, stability and deactivation are summarized. While, the proposed mechanisms on the bio-oil upgrading over the zeolite-based catalysts and the possibility for the application of the developed catalysts in the industrial process are discussed. Furthermore, the main strategies including metal modification, construction of zeolites with a hierarchical structure and synthesis of special morphologies with hollow structure or core/shell structure and nanosheet structures for the improvement of deoxygenation property performance are introduced. It is expected to provide a guidance for the design and fabricate more excellent zeolite-based catalysts and their application for high-quality bio-oil production from fast biomass pyrolysis.