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The chemical characteristics of lignin isolated from industrial black liquor were identified by gel permeation chromatography (GPC), Fourier transform infrared (FTIR) spectroscopy, and two-dimensional (2D) heteronuclear singlequantum coherence (HSQC) nuclear magnetic resonance (NMR), concerning its average molecular weight, distribution of typical interunit linkages, and functional groups. The frequency of β−O−4 linkage was determined to be 17−28/100 C 9 units by 2D NMR, while the content of unit [guaiacol (G), syringol (S), and p-hydroxyphenyl (H)] presents a ratio of 7:2:1.5 for G/S/H. The mass-average molecular weight of lignin was characterized to be 2238 g/mol by GPC analysis. The low polymerization degree of the units in lignin leads to the substantial extent of interunit linkage cleavage at low temperatures. The guaiacol-, syringol-, and phenol-type compounds from fast pyrolysis of lignin in a pyroprobe at 500 °C were notably identified by gas chromatography−mass spectrometry (GC−MS) and presented a ratio of the peak area as 7:2:1. More fragments were observed at higher temperatures from pyrolysis (Py)−GC−MS analysis, because of the commencement of demethoxylation and cracking of side chains. The scheme concerning the cleavage of characterized interunit linkages in lignin was proposed to produce the free radicals. The side chains on the free radicals were preferably to crack on β-site bonds to produce a number of methyl phenolic compounds. The methoxyl group was intensively cracked with the increased temperature because of its high bond dissociation energy (BDE), giving rise to the notable increase of cresol-, phenol-, and catechol-type compounds under high temperatures.

A novel porous material was realized for highly efficient post-combustion CO2 capture with high CO2 adsorption capacity, high selectivity and moderate heat of adsorption, mainly attributed to the suitable pore size and dual functionalities.

Creating secondary nanostructures from fundamental building blocks with simultaneous high loading capacity and well-controlled size/uniformity, is highly desired for nanoscale synergism and integration of functional units. Here a novel strategy is reported for hydrophobic quantum dots (QDs) assembley with porous templates, to form pitaya-type fluorescent silica colloids with densely packed and intact QDs throughout the silica matrix. The mercapto-terminated dendritic silica spheres with highly accessible centralradial pores and metal-affinity interior surface, are adopted as a powerful absorbent host for direct immobilization of QDs from organic phase with high loading capacity. The alkylsilane mediated silica encapsulation prevents QDs' optical degradation induced by ligand exchange and favors the homogeneous silica shell formation. These multiple QD embedded silica spheres exhibit good compatibility for different colored QDs with well-preserved fluorescence, high colloidal/optical stability, and versatile surface functionality. It is demonstrated that after integration with a lateral flow strip platform, these silica colloids provide an ultrasensitive, specific, and robust immunoassay for C-reaction protein in clinical samples as promising fluorescent reporters.