Isoconversional methods are commonly used to process the thermogravimetric analysis (TGA) data and to simultaneously obtain the effective activation energies for lignocellulosic biomass pyrolysis. However, the widely used isoconversional methods may lead to some systematic problems, for example, numerical instability for the Friedman method and significant errors in the kinetic parameters for the Flynn−Wall−Ozawa and Kissinger−Akahira−Sunose methods. To avoid the above problems, a modified Friedman isoconversional method has been developed in this work to accurately determine effective activation energies for solid-state reactions, such as biomass pyrolysis reactions. Through processing theoretically simulated data of strongly varying activation energy, the modified method applying for narrow intervals of conversion degree was proven to be capable of calculating the conversion dependence of activation energy accurately and reducing the effect of data noise. The modified Friedman isoconversional method was employed to process the non-isothermal TGA data of wheat straw pyrolysis at heating rates of 2.5, 5, 10, and 20 K min −1 and the kinetic data of beech sawdust pyrolysis at 5, 10, and 20 K min −1 from the literature. The results showed that the effective activation energies for the pyrolysis of wheat straw and beech sawdust varied significantly with the degree of conversion (in the conversion range from 0.05 to 0.85, the effective activation energies for wheat straw pyrolysis varied from 154 to 379 kJ mol −1 , while 155−316 kJ mol −1 was reported for beech sawdust pyrolysis).

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Uricase as an important healthcare-related protein is extensively used in the treatment of tumor lysis syndrome and in the manufacture of serum uric-acid diagnostic kits. In this study, a gene of a new thermostable uricase (KmUOX) was cloned from thermotolerant yeast . The uricase was fused with a self-cleaving intein and cellulose-binding affinity tag and expressed in BL21 (DE3). Through the binding to inexpensive cellulose and in situ intein cleavage induced by a pH change, tag-free uricase (KmUOX) was efficiently purified with a 77.11% yield via a single-step column purification strategy. This tag-free uricase showed ,, and values of 67.60 µM, 56.35 µM/(min mg), and 32.74 S, respectively. Furthermore, this pure uricase was relatively thermostable and retained 79.75% of activity when incubated at 40 °C for 90 h. Thus, this pH-induced self-cleavable intein system combined with a cellulose matrix for affinity chromatography is proven here to be an effective and low-cost method for recombinant-uricase purification. Moreover, the stability of KmUOX makes it useful for clinical applications.

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An efficient bioflocculant-producing strain, Raoultella ornithinolytica 160-1, was identified by 16S rRNA and mass spectrometry analyses. Rapid production of bioflocculant EPS-160 was obtained with 10.01 g/(L⋅d) after optimized by response surface methodology. With the aid of Al(III), more than 90% flocculation activity of EPS-160 at 8 mg/L dosage was achieved in 5 min. Thus, this novel Al(III) dependent bioflocculant was used in combined with chemical coagulants AlCl3 to remove kaolin suspensions and wastewater treatment. The results indicated that the addition of EPS-160 in aggregation system not only largely improved the flocculation ability than the individual use of chemical flocculant (over 30 percent), but also overcome the decrease of flocculation activity due to the overdose of AlCl3 and maintained the optimum dosage of AlCl3 in a wide range (11–23 mg/L). The zeta potentials and EPS-160 structure indicated that both charge neutralization and bridging were the flocculation mechanism with kaolin. During the wastewater treatment, this composite flocculants consisted of EPS-160 and AlCl3 also had great performance for turbidity elimination. Moreover, with the properties of high flocculation activity, hyperthermal stability, pH tolerance and non-toxicity, EPS-160 shows great potential applications.