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The present study focuses on the word length distribution (WLD) of Zhuang language. The results show that the WLDs of all texts investigated can be described by the Positive Cohen-Poisson model whe...

Glass multi-station bending machining (GMBM) is a high-precision and efficient glass processing technique for smartphone curved screen in 3C industry. In this paper, simulation model of the GMBM of smartphone curved screen was researched by using MSC Marc software. The stress relaxation and structural relaxation models of glass material were used in the numerical model to accurately predict the forming process of the glass component. The effects of process parameters of GMBM, namely heating rate (HR), holding time, bending temperature (BT), bending pressure and cooling rate (CR), on the product quality characteristics (residual stress and shape deviation) and energy efficiency were analyzed based on orthogonal experiments. It can be found that the BT, CR and HR have extremely important effects on product residual stress, shape deviation and energy efficiency. Furthermore, a multi-objective optimization method based on NSGA-III (a non-dominant sorting genetic algorithms based on reference points) was applied to efficiently solve the optimization problem between glass product quality and energy efficiency. The optimal parameter schemes with high quality and low energy efficiency were obtained by the Pareto front of multi-objective, and the average prediction errors of the numerical results by the optimized schemes are no more than 20% through confirm experiments. The optimized schemes improve the stability of the process of GMBM, which can deal with the challenge of green manufacturing.

In order to overcome the influence of various uncertain factors on the quality of chestnuts in the process of manual detection, an online detection method based on acoustics was proposed. In this paper, a multilevel inspection platform for chestnut surface defects based on acoustics is constructed to realize real-time acquisition and measurement of chestnut surface defects. Through acoustic detection, the sound collected from the feature area is converted into a time-frequency map, and image processing was performed using matlab software. At the same time, in the return air detection, the chestnuts with wormholes will produce a return air, which was used as the secondary detection of the chestnuts. This study provides a useful reference for chestnuts quality testing and improves the objectivity and accuracy of chestnuts quality testing.

From the current development trend of mobile phone industry, 3D curved glass screen is undoubtedly the hot spot of the industry, and glass molding processing (GMP) is the main method of 3D curved glass manufacturing at present. 3D curved glass is a kind of curved glass which is formed by heating, softening, and annealing process in the mold. In GMP, process parameters not only determine the efficiency and quality of curved glass processing, but also affect the emission of CO2. Moreover, there is no definite mathematical model for the influence of these involved process parameters on the effect of hot bending. In this paper, the GMP experiment of the finished glass is carried out, and the relationship between the processing parameters and the processing quality of the finished glass is summarized. Furthermore, the experimental data is analyzed to investigate the influence of process parameters on performances of GMP. By cuckoo search algorithm method, the parameters of GMP are optimized.

To establish a prokaryotic expression and purification protocol for nuclease P1 (NP1), we first obtained a synthetic NP1 by splicing 22 oligonucleotides with overlapping PCR. We constructed and transformed a secretory expression vector pMAL-p4X-NP1 into Escherichia coli host strains T7 Express and Origami B (DE3) separately. Then, the recombinant NP1 was purified by amylose affinity chromatography, and its activity, thermo-stability and metal-ion dependence were investigated systematically. The results indicated that the expressed fusion proteins MBP-NP1 (Maltose binding protein-NP1) existed mainly in soluble form both in host strains T7 Express and Origami B (DE3), but the specific activity of recombinant protein from Origami B(DE3) strain was higher than T7 Express strain (75.48 U/mg : 51.50 U/mg). When the MBP-tag was cleaved by protease Factor Xa, the specific activity both increased up to 258.1 U/mg and 139.2 U/mg. The thermal inactivation experiments demonstrated that the recombinant NP1 was quite stable, and it retained more than 90% of original activity after incubated for 30 min at 80 degrees C. Zn2+ (2.0 mmol/L) could increase enzyme activity (to 119.1%), on the contrary, the enzyme activity was reduced by 2.0 mmol/L Cu2+ (to 63.12%). This research realized the functional expression of NP1 in the prokaryotic system for the first time, and provided an alternative pathway for NP1 preparation.