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Oxygen indicator can monitor the quality and safety of the food that transport from producers to consumers by perceiving the oxygen concentration in packaging, and then inform the consumer about the product’s safety, shelf life and availability by sensing the visually physical change, which will widely used for modified atmosphere packaging in food packaging.

Based on the theory and method of eco-efficiency, the relative efficiency index (Ri) was constructed in the paper. According to the range of the relative efficiency index, the industrial sectors can be divided into four categories. When Ri≥R+0.5δ , the industry should be encouraged. When R≤Ri

Because of China's various regions in geographic location, population, resource endowment, economic and technical conditions are different. Therefore, in the practice process, we should suit one's measures to local conditions to choose promotion mechanism of regional circular economy development by considering factors of regional resources and economic development level. This paper summarizes the type of mechanism to promote circular economy, based on the analysis characteristics of resources and the environment, social development, and circulating levels of economic development of eastern, central and western regions, proposed market mechanism will be more conductive to the advance of the future development of circular economy of the eastern region, government guidance, enterprise practice, public participation mechanism for promoting cooperative development model more in line with the circular economy development stage of the central region, and promoting mechanism dominated by the government will effectively promote the development of circular economy in the western region. At the same time, this paper proposed specific implementation path of all promoting mechanism.

This paper introduced the structure and principle of DC servo motor, , derived its transfer function; combined BP neural network with PID control to achieve a composite control arithmetic, that fully embodies advantages of strong self-adaptive, robustness of neural network and high steady-state accuracy of PID controller, which improved the performance of DC motor servo system.

Biodegradable poly (propylene carbonate) (PPC) composite with a slight improvement in the thermal stability and tensile strength was successfully prepared by incorporating a low content of nano-SiO2. Tensile tests demonstrate the better mechanical properties of the composites prepared in this study. The obtained composites increases sharply from 1.57Mpa to 12.04Mpa by incorporating 5wt% nano-SiO2. Furthermore, the composites show approximately 8°C higher glass transition temperature (Tg) than that of neat PPC.The Tdmax of composite with 5wt% of nano-SiO2 was about 40°C higher than that of neat PPC.

Using Ca(NO3)2·4H2O, (NH4)2HPO4 and ammonia water as the starting raw materials and L-DOAP as template, hydroxyapatite (HAP) crystals were successfully prepared at 180 °C by changing the hydrothermal time. The HAP crystals were characterized by X-ray diffractometry (XRD), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscope (FESEM). The XRD patterns indicate that increasing hydrothermal time is helpful to improve the purity of the product and enhance crystallinity of HAP crystal. The FTIR analysis shows that the carbonate ions enter into the HAP crystal lattice and the final products are carbonate-containing hydroxyapatite. The FESEM images illustrate that HAP crystal morphology changed to flower-like hierarchical structures and grass blanket-like hierarchical structures when increasing the hydrothermal time to 1 h and 24 h. Therefore, hydrothermal time has a great influence on the morphology of HAP and the possible formation mechanism of HAP samples has been discussed.

With the rapid development of the smart grid in our country, we need many 10kV smart switches which can protect the safety of the line and complete the reasonable scheduling of the electricity load. In order to realize the reliable power supply for 10kV smart switch, power supply system based on photovoltaic cell technology is designed. In this paper, firstly, we have a brief introduction about the 10kV smart switch. Secondly, composing and principle of the power supply system is introduced. And then, principle of the energy harvesting converter main circuit is analyzed in detail. Then, the MPPT method of the photovoltaic cell based on impedance matching is studied. Test show, the power supply system is suitable for 10kV smart switch measurement and control.

It is a trend to reduce multiple pollutant emissions simultaneously by one kind of reduction policies or measures, as the pollution control and emission reduction are in a grim situation in China. And the synergistic effect research of the reduction measures is the basis which can help make the correct measures. The paper first shows the definition of the synergistic effect, then, elaborates the relationship between the reduction measures and the synergistic effect. Besides, the development and the evaluation methods of the reduction measures are also illustrated. Finally, some reasonable suggestions on research of the synergistic effect are given.

Industrialization process cause a huge material input, waste discharge and environmental impact. To realize the sustainable development of society and reduce environmental pressures are caused by economic and social activities, process simulation of industrial metabolism and its environmental effect analysis have become a hot issues in the international research field. Around the key scientific issues of regional material metabolism, this project fully learn and absorb domestic and international research results. The empirical study focus on energy (coal) and chemical industry base in china, starting from material metabolism analysis of regional industrial system, analyze the relationship between industrial system material metabolic processes and environmental effects, establishing the environmental effects index model of industrial metabolic with the environmental effects analysis; eventually propose the approaches and countermeasures to reduce environmental effect of industrial system material metabolic.

Pt is used as a heating resistor by sensors based on ZrO2. A heating resistor will directly influence the response rate and life expectancy of the sensor. The service life of heating resistor using pure Pt is very short , in order to improve the quality of resistor, this paper studies the addition of ceramic powder to Pt paste by intermittent thermal shock test of heating resistor slurry life, the method of square resistance test, and using SEM to observe the microstructure of Pt resistor. Then the reasonable Pt paste formula of heating resistor is obtained.

Novel four-arm star-shaped (STEO) plasticizer was synthesized and characterized by FT-IR and NMR methods. The mixtures of STEO and ethylene carbonate (EC) were used as plasticizers in polyethylene oxide (PEO)-based polymer electrolytes. The effects of plasticizers on the thermal properties and the ionic conductivities of polymer electrolytes were reported. Results showed that the addition of plasticizers could effectively decrease the melting temperatures and the degree of crystallization of polymer electrolytes, and the ionic conductivities increased with the addition of plasticizers. When the mass ratio of STEO and EC was 1:1, mixed plasticizer had the best plastifying effect on the gel polymer electrolytes.

A thick film ZrO2-based NOx sensor feasible for diesel and gasoline engine applications has three diffusion paths, the size of paths has a great influence on sensor signal output. This paper studies the relationship between the pump current signal and the size of paths, the manufacture of NOx sensors of varied path sizes by the method of filling organics and then sintering at a high temperature to form a stable path, and detections of the sensors in a standard gas chamber. Then matching sizes of three paths are obtained.

In order to explore high strength organic electrotransporting electroluminescent (EL) materials, twelve new pyrazole oxadiazole compounds containing the benzothiazole or benzene group in the 1 position of pyrazole, the aromatic group in the 3 position of pyrazole and the formacyl group in the 4 position of pyrazole were designed and synthesized. A new method of synthesizing 1,3,4-oxadiazole compound was described. Their structures were characterized by IR, MS, 1H NMR spectra and elemental analysis. The fluorescence properties were measured by fluorometry. The results showed that the target compounds had good fluorescence and λem ranged from 410nm to 450 nm and fluorescence quantum yields up to 0.69.

The hydrodynamics of particles of coarse coal slime and quartz of different sizes in a liquid-solid fluidized bed separator were investigated experimentally, including minimum fluidization velocities, bed expansion ratios, and segregation of mixed particles with two methods. Experimental parameters studied included density and size of particle, superficial water velocity and initial static bed height. The results provide a reference for choice of size scope on coarse coal slime separation by liquid-solid fluidized bed separators.

Solid base CaO was prepared and characterized, which was used to catalyze depolymerization of lignite in supercritical methanol. Methanolysis products were analyzed by gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FTIR). The results showed that the solubility of methanolysis products in organic solvent increased, the majority species of methanolysis products were aliphatic hydrocarbon and oxygenated compounds such as alkyl substitution phenol. CaO can catalyze selective depolymerization of lignite with the reaction of cleavage of ether bond under given condition.

To understand the distribution of the alkylene bridge bonds which connect aromatic moieties and utilize coal effectively, Shenfu coal (SFC), its solvent extraction fractions and carbon disulfide (CS2)/tetrahydrofuran (THF) inextractable matter (RE) were subject to ruthenium ion-catalyzed oxidation (RICO). The results suggest that the carbon number of the alkylene bridge bonds range from C0 to C30 and that dominant alkylene linkage are C2 and C3 in SFC, a,w-diarylalkanes are soluble in a CS2/THF mixed solvent, whereas highly condensed aromatic species in SFC show poor solubility in the CS2/THF mixed solvent.

Risk matrix is applied to evaluate seismic risk on mountainous bridge. In this article, a continuous bridge is used as example to analyze the seismic risk of key position under a usual earthquake. Related control method is proposed to provide technical support for bridge seismic design and operation maintenance.

A large number of non-dispersible underwater concrete materials will be extensively used in works which span over rivers and sea, so it is important to study the performance of non-dispersible under water concrete structures. Non-dispersible underwater concrete is the concrete mixing with special additives-anti-washout admixture, which is a kind of water-soluble polymers with long-chain structure and strong absorption capacity. In the present paper, the axial and eccentric compression performance of non-dispersible underwater concrete columns were experimentally investigated. The failure modes and loading capacity of the columns of non-dispersible underwater concrete were mainly discussed. The experimental results showed that the compression performance of non-dispersible underwater reinforced concrete columns and the common reinforced ones are similar in some aspects.