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Micro-energy networks have been widely used in power distribution systems. Previous studies have not addressed how to avoid these networks being dependent on the grid, due to the instability of distributed energy sources, or the lack of specific quantification of environmental and economic benefits. To understand the overall potential of the micro-energy network system for reducing environmental impacts, a life cycle assessment was conducted for the industrial park in Jinan. The analysis used a “cradle to gate” system boundary and a 1-year operation of the micro-energy network as the functional unit. The HOMER software was applied to build the research object’s micro-energy network model and to carry out load analysis. The environmental impact and financial costs of the micro-energy network system have been estimated for different combinations of gas turbine units and water chilling units. The results show that all optimized scenarios could achieve an environmental impact reduction of more than 50% when compared to the initial scenario, regardless of the benefits of exporting surplus electricity. A reduction in environmental impacts as high as 71% could be achieved in optimized scenarios, although total costs would be 13% higher. The categories of freshwater ecotoxicity, marine ecotoxicity, human carcinogenic toxicity, and human noncarcinogenic toxicity were determined as the key impact categories. The impact of different electricity generation and the environmental benefits of exporting electricity are discussed. We concluded that micro-energy networks integrating natural gas and renewable energy technologies could bring about significant environmental benefits.

The largest contributor to pollutant emissions is the sintering process in steel industry. Ultra-low emission policy for the Chinese steel industry states that emission concentrations of particulate matter, SO2 and NOx should not exceed 10, 35 and 50 mg/m3 respectively. The emission concentrations of the steel industry are the same as the ultra-low emission policy for the coal-fired power industry, but the pollutant control technologies of the two industries are different. Life cycle assessment method is applied to analyze the latest ultra-low treatment process for sintering flue gas emissions which includes electrostatic precipitation, ozone oxidation, wet desulfurization, wet denitration, condensation dehumidification and wet electrostatic precipitation. Following this novel ultra-low emission treatment, the concentrations of particulate matter, SO2, NOx, and PCDDs in the sintering flue gas decreased very significantly, attaining the new emission standard. With 1 ton of sinter as the functional unit and “cradle to gate” as the system boundary, the environmental impact of the process is 0.1811 and the total economic cost is 172.79 RMB, of which internal cost is 34.64 RMB and external cost is 138.15 RMB. The main environmental impacts result from applying the wet denitration and ozone oxidation processes. Sodium sulfite in the wet denitration process, and electricity and liquid oxygen in the ozone oxidation process are the key inputs that cause environmental impact. These findings are useful for a further optimization of the ultra-low emissions process from both the environmental and economic perspective, which is applicable in other regions of the world.

This study presents a new solution for the dynamic behavior of in-plane and out-of-plane motion of a curved pipe conveying fluid, using the generalized integral transform technique (GITT). The system of sixth- and fourth-order partial differential equations governing three-dimensional motion of the curved pipe is integral transformed into three coupled systems of second-order ordinary differential equations, which are solved numerically by using the NDSolve routine of Mathematica. Excellent convergence behavior of the GITT solution is shown by comparing the vibration deflections at different points along the curved pipe centerline obtained with of different truncation orders. The results of natural frequencies and vibration responses compare well with available results in the literature obtained by other methods. Furthermore, we investigate the dynamic behavior of the curved pipe with different axial forces, flow velocities and other vibration parameters. A relationship between boundary conditions and axial forces is provided, and a series of vibration displacement and velocity trajectories is obtained. It is shown that the GITT is a convenient and effective mathematical method for vibration analysis of the curved pipe conveying fluid and can be used for further study of the dynamics of variable-curvature curved pipes.

Vibration of a pipe conveying two-phase flow is a major concern in ocean engineering, and it is necessary to formulate a proper damping model to avoid excessive flow-induced vibration in pipes. While only a few studies have investigated the effects of damping model on dynamics of pipe conveying flow, in this work, we focus on the dynamic behavior of pipe induced by the gas–liquid two-phase flow using a combined damping model. The Generalized Integral Transform Technique (GITT) is employed to model the dynamic behavior of the pipe conveying two-phase flow, and the governing equation of vibration is transformed into a coupled system of second order ordinary differential equations in the time domain by GITT method. Parametric studies are performed to investigate the effects of damping ratios on the dynamic behavior of the pipe, and the results from this model have been verified against the existing experimental results. Besides, the dimensionless critical frequency of the pipe at which instability sets in has been predicted both in the real and imaginary part. Finally, a dimensionless structural parameter γ 0 that can govern the normalized stability envelope of the pipe is obtained. The proposed model for the dynamics of the pipe conveying two-phase flow with combined damping can be an important reference for the design and analysis of deepwater risers.

Regional sustainable development has become a worldwide issue in recent years, but there is no single and universally agreed method of choosing indicators for sustainable development assessment. The subjective selection of indicators will affect the results of assessment. Each evaluation method has its own advantages and disadvantages, and the methods used to determine indicator weight also differ. Regional sustainable development is a complex system, which is difficult to evaluate objectively and scientifically using a single method. Therefore, a new integrated indicator system and evaluation model is constructed here to more accurately reflect regional sustainable development level. The indicator system and evaluation model were constructed using a case study of 17 cities in Shandong Province, China. The indicator system includes 4 subsystems, i.e., economy, society, resource, and environment. These indicators were selected through correlation analysis and discrimination analysis. A back propagation neural network was applied to evaluate the respective scores of the 4 subsystems. The comprehensive score for regional sustainable development was evaluated using the analytic hierarchy process with entropy correction. The results show that sustainable development levels in these 17 cities show a gradually decreasing trend from east to west and from coast to inland. Cities with an underdeveloped economy usually display poor levels of social development and serious environmental pollution. Through the improvement of indicator screening, evaluation model, and result correction, the error caused by a single evaluation method can be reduced significantly. This new methodology for indicator selection and comprehensive evaluation provides a new perspective for the assessment of regional sustainable development.

The cluster manifold becomes an essential part in a subsea production system and it has been widely used in the development of ultra-deepwater oil and gas fields. One hand, it can gather the production fluid from subsea wells. On the other hand, it can distribute water, gas and chemical agents from the floating production system to each subsea well. Hence, the failure of subsea cluster manifolds may not only lead to the stagnation of production wells and economic losses but also cause environmental pollution and human health in severe cases. Therefore, the reliability of subsea cluster manifolds is quite of importance and it should be studied for the safety service of the subsea production system. Based on the fault tree analysis (FTA), this paper will discuss the failure cause of six well slots subsea cluster manifolds in LiWan 3-1 gas field in China South Sea. Considering the pipeline structure, control system and flow assurance, the fault trees of subsea cluster manifolds are built. Meanwhile, the importance degrees of each elementary event are ranked orderly and the minimum cut sets are obtained through analyzing the structure important of the FTA. The failure major reasons are obtained and the preventive measures are proposed, which could have some guiding significance for the operations of subsea cluster manifolds system in China South Sea.

Severe acute respiratory syndrome coronavirus (SARS-CoV) is responsible for SARS infection. Nucleocapsid protein (NP) of SARS-CoV (SARS_NP) functions in enveloping the entire genomic RNA and interacts with viron structural proteins, thus playing important roles in the process of virus particle assembly and release. Protein–protein interaction analysis using bioinformatics tools indicated that SARS_NP may bind to human cyclophilin A (hCypA), and surface plasmon resonance (SPR) technology revealed this binding with the equilibrium dissociation constant ranging from 6 to 160 nM. The probable binding sites of these two proteins were detected by modeling the three-dimensional structure of the SARS_NP–hCypA complex, from which the important interaction residue pairs between the proteins were deduced. Mutagenesis experiments were carried out for validating the binding model, whose correctness was assessed by the observed effects on the binding affinities between the proteins. The reliability of the binding sites derived by the molecular modeling was confirmed by the fact that the computationally predicted values of the relative free energies of the binding for SARS_NP (or hCypA) mutants to the wild-type hCypA (or SARS_NP) are in good agreement with the data determined by SPR. Such presently observed SARS_NP–hCypA interaction model might provide a new hint for facilitating the understanding of another possible SARS-CoV infection pathway against human cell.

Uniform fluorescein isothiocyanate (FITC)-incorporated silica-coated core-shell SPIO nanoparticles (MNP@SiO2) with sizes of about 30 nm have been prepared by controlled hydrolysis of tetraethyl orthosilicateb. Monoclonal antibody nimotuzumab (h-R3) is labeled to the core-shell MNP@SiO2 for targeting to cancer cell A431 overexpressing epidermal growth factor receptor (EGFR). The result shows h-R3 labeled MNP@SiO2 nanoparticle (MNP@SiO2-mAb(h_R3)) has desired specificity to cancer cell A431. Compared to BSA labeled MNP@SiO2 nanoparticle (MNP@SiO2-BSA), MNP@SiO2-mAb(h_R3) could increase the cellular uptake of endocytosis and cytotoxicity due to h-R3 binding.

Poly(ethylene glycol) was functionalized with carboxyl groups by esterification with succinic anhydride in the media of dioxane and pyridine as catalyst. Maghemite nanoparticles were synthesized by chemical coprecipitation and coated with carboxylated poly(ethylene glycol) to improve their biocompatibility. And the properties were characterized using Fourier transform infrared spectroscopy, Transmission electronic microscopy, X-ray diffraction, Zeta potential analyzer and Vibrating sample magnetometer. The immunomagnetic nanoparticles were obtained by grafting anti-sperm protein 17 monoclonal antibody onto the surface of carboxylated poly(ethylene glycol) coated maghemite nanoparticles by covalent bonds. After incubated with human sperm protein 17 gene transfected ovarian cancer HO8910 cells, the immunomagnetic nanoparticles were targeted successfully to the positive cells and no obviously non-specific adsorption occured. It is of significance to target to the cell successfully for diagnosis and therapy of ovarian carcinoma such as magnetic resonance imaging and magnetic hyperthermia.

Sperm protein 17 (Sp17) is a testis-specific protein involved in acrosome reaction in spermatozoa. However, the Sp17 gene has been recently detected in normal non-testis tissues and malignant neoplasias. Therefore Sp17 may be a potential target for immunocontraception and a suitable target for tumor immunotherapy. This paper reviews the advances in the protein characterization, expression and distribution, and biological function of Sp17 and its clinical research.