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As an important glycosaminoglycan hydrolase, chondroitin lyases can hydrolyze chondroitin sulfate (CS) and release disaccharides and oligosaccharides. They are further divided into chondroitin AC, ABC, and B lyases according to their spatial structure and substrate specificity. Chondroitin AC lyase can hydrolyze chondroitin sulfate A (CS-A), chondroitin sulfate C (CS-C), and hyaluronic acid (HA), making it an essential biocatalyst for the preparation of low molecular weight chondroitin sulfate, analysis of the structure of the chondroitin sulfate, treatment of spinal cord injury, and purification of heparin. This paper provides an overview of reported chondroitin AC lyases, including their properties and the challenges faced in industrial applications. Up to now, although many attempts have been adopted to improve the enzyme properties, the most important factors are still the low activity and stability. The relations between the stability of the enzyme and the spatial structure were also summarized and discussed. Also perspectives for remodeling the enzymes with protein engineering are included.

The NiFe2O4 magnetic nanoparticles (NF‐MNPs) were prepared for one‐step selective affinity purification and immobilization of His‐tagged recombinant glucose dehydrogenase (GluDH). The prepared nanoparticles were characterized by a Fourier‐transform infrared spectrophotometer and microscopy. The immobilization and purification of His‐tagged GluDH on NF‐MNPs were investigated. The optimal immobilization conditions were obtained that mixed cell lysis and carriers in a ratio of 0.13 in pH 8.0 Tris‐HCl buffer at 30℃ and incubated for 2 h. The highest activity recovery and protein bindings were 71.39% and 38.50 μg mg–1 support, respectively. The immobilized GluDH exhibited high thermostability, pH‐stability and it can retain more than 65% of the initial enzyme after 10 cycles for the conversion of glucose to gluconolactone. Comparing with a commercial Ni‐NTA resin, the NF‐MNPs displayed a higher specific affinity with His‐tagged recombinant GluDH.

Damage caused by people and organizations unconnected with the pipeline management is a major risk faced by pipelines, and its consequences can have a huge impact. However, the present measures to monitor this have major problems such as time delays, overlooking threats, and false alarms. To overcome the disadvantages of these methods, analysis of big location data from mobile phone systems was applied to prevent third-party damage to pipelines, and a third-party damage prevention system was developed for pipelines including encryption mobile phone data, data preprocessing, and extraction of characteristic patterns. By applying this to natural gas pipelines, a large amount of location data was collected for data feature recognition and model analysis. Third-party illegal construction and occupation activities were discovered in a timely manner. This is important for preventing third-party damage to pipelines.

Dents in an oil and gas pipeline can be detected by In-line-Inspection (ILI), and structure integrity analysis of the pipe with theses reported dents is important for the safe operation. Strain analysis of the dented pipe is a way of fine assessment and ASME B31.8 has established the strain assessment code and its acceptable range. However, the method of strain assessment is rarely used due to the difficulty of strain calculation for a buried pipe. In this study, features of ILI data are investigated to elaborate the necessary of filtering analysis for strain analysis of the dent with ILI data. Then typical filtering methods are used to smooth the ILI data, and strain analysis are carried out with the smoothed data to study the practicability of strain assessment. Profile and strain of a dent in D813 pipe were obtained by Finite Element Method (FEM). Then different filtering methods were used to smooth the simulated ILI data of the dent which were selected from FEM profile. Strain of the dent were also calculated by smoothed data with the latest ASME B31.8 code, and compared with it from FEM at last to prove the feasibility and validity of the filtering methods with ASME B31.8 code.

Recently incidents related to cracking of girth welds in oil and gas pipelines occurred frequently. With highly concentrated stresses, girth weld defects may significantly reduce bearing capacity of pipelines. Many girth weld defects were detected in the in-line inspection and excavated verification. How to assess the severity of these defects to avoid the excessive and unnecessary repair was a technical challenge. Four different kinds of girth weld defects were manufactured in the 32-inch pipeline and full-scale hydrostatic burst testing were carried out to assess the pressure performance of these defects. Many fitness-for-purpose assessment methods were applied to verify the accuracy of experimental results. After the testing, pipelines with failure defects were cut out to carry out the microanalysis. The research results make us understanding the severity of these defects and avoid the excessive and unnecessary repair of these defects to ensure the pipeline safety.

Modern structures tend to be more and more complicated, setting up the complete calculation model and getting each part of the dynamic response is almost impossible and unnecessary. The substructure analysis technology is effective for the dynamic analysis of large and complex structure. The substructure theory has become increasingly mature and perfect, and has been widely used in structural analysis and calculation. This article simply introduces the principle of substructure pseudo dynamic test, and using the finite element software—ADINA simulates a steel frame.

Use Adina finite element software, established the finite element model of the the volume 10000m3LNG storage tank, against the concrete outer tank of full containment type LNG storage tank vertical seismic action seismic response analysis. Take acceleration seismic input method, select the four categories venue seismic waves, LNG storage tank stress analysis of vertical seismic action, come in different earthquake LNG storage tank outer tank equivalent stress, hoop stress and axial stress distribution.

This paper established three-dimensional calculation model of three large space shear wall structures of different thickness,using finite element software ANSYS to analyze the wind loads and vertical loads of the internal force. And analyze the displacement, internal force distribution pattern. Under the wind loads and vertical loads of three different thickness wall of the large space wall structure.

Established three-dimensional calculation model of three large space shear wall structures of different thickness, using finite element software ANSYS to calculate the seismic response analysis of these models,obtained time-displacement curves and stress distribution under earthquake structures of three large space shear walls of different thickness, and its comparative analysis; shows practical significance of large space shear wall structure.

This paper select the appropriate calculation and analysis models and examples, using finite element analysis software ANSYS to compare and analyze the dynamic properties of three large space shear walls of different thickness. The result indicated: the effects of the large space shear wall structure to torsion with the increase of wall thickness.

According to the traffic load, road surface temperature, pavement structure parameters and the creep parameters of asphalt mixture of Jiqing highway, the freeway asphalt overlay rutting depth prediction model is constructed with ABAQUS finite element analysis software to simulate numerically on overlay rutting depth, and the relationship among the axial load times, overlay thickness and the rutting depth is studied at the same time. The results of the study show that, the theoretical calculation agrees well with measured results of rutting depth, the relationship among the overlay thickness, the axle load times and the rutting depth coincides with logarithmic function model, and in the same asphalt overlay height, anti-rutting ability on AC-20 is better than that of AC-25 ,AC-20 and AC-25 combinations.

An algorithm designed to assist in devising shunting schedules for railway stations is described in this article. The algorithm combines probabilistic local search assisted by PERT (Program Evaluation and Review Technique), which reduces the universe of choices considered by the local search. Experiments with the algorithm using an actual train schedule showed it to work rapidly and provide effective scheduling choices.

Shunting scheduling problems at railway stations can be regarded as a sort of resource constrained project scheduling problem (RCPSP). Unlike the normal RCPSPs, however, shunting scheduling problems require that the number of work which consists of a project has to be dynamically changed in the process of solving the problem and some of the work has to be performed at a prescribed timing, for example. We propose an efficient algorithm for shunting scheduling problems combining probabilistic local search and PERT. Local search and PERT are combined so that the candidates for answers in the local search process are evaluated by PERT. This enables us to reduce the search space of the local search to a great extent and makes the algorithm work quite fast. We have confirmed the effectiveness of our algorithm through several experiments using practical train schedule data.