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The effect of different carbon sources was studied relative to the treatment effect of aerobic denitrifying bacteria during the treatment of nitrate-containing wastewater as well as the influence of co-metabolism flora. Three carbon sources, i.e., glucose, citric acid, and sodium acetate, were selected to study the changes in the pH, nitrate nitrogen, chemical oxygen demand removal, nitrite nitrogen concentration, physical and chemical properties of sludge and volatile fatty acids, and high-throughput sequencing to study any changes in flora. The results showed that the denitrification ability of the system using citric acid as the carbon source was stronger than the denitrification ability of the system using glucose or sodium acetate as the carbon source. The removal of nitrate nitrogen in the system was the result of the co-metabolism of acid producing bacteria and aerobic denitrifying bacteria. Due to the greater number of types and greater amount of dominant bacteria in the sludge domesticated and cultured with citric acid as a carbon source, the co-metabolism flora formed was more stable, so it could better remove nitrate nitrogen.

Mucin 1(MUC1) is an effective marker of breast cancer, so it is of great significance to develop a simple, sensitive and highly selective MUC1 detection sensor. Herein, we constructed a label-free nanopore biosensor for rapid and highly sensitive detection of MUC1. The presence of MUC1 triggered the modification of the DNAzyme walking chain on the surface of Fe

To enhance nitrogen removal of fermentation pharmaceutical wastewater with high nitrogen load, a full-scale process based on simultaneous partial nitrification-denitrification/ anammox/ sulfur autotrophic denitrification (SPAS) was established via inoculating with bioaugmentation consortia in a modified two-stage AO. More than 93 % TN and 98 % NH

DNA methylation is catalyzed by DNA methyltransferase (DAM) and plays an important role in many biological processes. The monitoring of DAM activity is of great significance in disease diagnosis. In this paper, an electrochemical DNA biosensor was developed for DAM detection via recognition of DNA tetrahedron and SiO2@Au core/shell nanoparticles-based amplification technique. We immobilize the DNA tetrahedron on the gold electrode surface to construct a well sensing interface. SiO2@Au core/shell nanoparticles was selected to achieve signal amplification for improving the sensitivity. The detection limit of DAM activity by the proposed method was reduced down to 0.0005 U mL−1. The proposed sensing system also showed ideal specificity, repeatability and stability. Moreover, the novel sensor developed could serve as a highly sensitive probe for DAM detection and shows great potentials in designed drug therapy, clinical diagnostics.

A simple one-step electrodeposition method is described to fabricate three dimensional ordered macroporous chitosanprussian bluesingle walled carbon nanotubes (3DOM CSPBSWCNTs) film onto the gold electrode surface to fabricate a copper ions (Cu2+)-specific DNAzyme biosensor. The new sensing strategy for sensitive and selective detection of Cu2+ was based on Au nanorods (AuNRs) as signal amplification labels. The electrochemical signal of glucose increased with the concentration of Cu2+ increasing. The morphologies and electrochemistry of the composites were investigated by using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electrochemical techniques including cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) and so on. Linear correlations of copper ion concentration were obtained in the range from 10−18 M to 10−5 M, achieving with a limit of detection of 10−19 M (S/N=3). Parameters affecting the biosensor response such as temperature, the cleavage time and the time of hybridization were optimized. This biosensor showed a wide range, low detection limit, good reproducibility and high stability. Additionally, these striking properties endow the biosensor with a great promise for analytical applications.

This paper outlines a series of studies on particulate and aggregative fluidization, starting from its first observation in the 1940's and culminating in its modeling, which both discriminates and reconciles these two types of fluidization, and in the experimental corroboration of the model with the use of supercritical carbon dioxide. These studies span three generations of efforts over the course of half a century and provide valuable knowledge in the interactive use of these two types of fluidization in developing new processes. The paper also outlines what to expect in extending this knowledge base into the next half century.

Solid particles belonging to Geldart Group A, B and D were fluidized in liquids of changing viscosity and in CO2 under ambient to supercritical conditions. Local bed voidage signals were collected and processed in conjunction with global expansion characteristics to give quantitative indexes for evaluating fluidization quality. Results showed that the fluidized state changes progressively from aggregative to particulate when fluidized separately by gas, supercritical fluid and liquids, indicating an infinite number of intermediate states existing between aggregative and particulate fluidization. A discrimination number Dn is proposed to describe the transition from particulate to aggregative. A heterogeneity index δ and a nonideality index fh are proposed to quantify, respectively, the local and the global characteristics of the intermediate states.

Information technology and network technology is developing rapidly, the relationship between firms and customers are becoming increasingly important. According to the management characteristics of CRM, the paper applies modeling methods and tools of UML to analyze and design sale management system online. This paper builds system development models, including the use case diagrams, the class diagrams, the activity diagrams and the timing diagrams, and develops the system for a sale company. It proves that UML can be used in sale system online designing and make the progress more easy and effective.