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A simple and clean way of extraction of natural essence from green tea leaf by supercritical CO2 was developed. The optimum extraction conditions to produce the high-quailty natural essence were found: loading about 100g/L, operating at 5000 psi and 50 °C, and separation kettle temperature 75 °C, static extraction three times with 40 min every time, the yield of natural essence was 0.5%. The product was analyzed by gas chromatography-mass spectrometry (GC-MS) show that dimethylsulfide was the characteristic aroma components of the natural essence with more than 50 kinds of alcohols, ketones, aldehydes, ethers and esters etc.. There were only little other biochemical composition of raw material and 0.4% caffeine in the product detected by high-performance liquid chromatography (HPLC), and the biochemical composition in the raw material were almost no loss before and after extracted by supercritical CO2, it indicated that the specificity of the method for extraction tea natural essence is very strong, and propitious to improve the secondary utilization of the tea raw materials.

The carbon-encapsulated superparamagnetic colloidal nanoparticles (SCNps) were rigidized into soft solids by embedding the SCNps into polyacrylamide hydrogel matrixes under the induction of an external magnetic field. Stabilized by the balance of attractive (magnetic) and repulsive (electrostatic) forces, the SCNps form one-dimension photonic crystal structures along the direction of the external magnetic field and further the structures are frozen into the solidified polymer matrix. The polymer matrix embedded one-dimension photonic crystal structures can strongly diffract visible light and present brilliant color in the light. This novel and soft solid polymer matrix that could be shaped and sliced not only paves a new avenue for develop novel magnetic-responsive photonic crystal materials and devices, but also provides a method to observe the magnetic-induced self-assembly structures of the SCNps in media such as polyacrylamide hydrogel matrixs as a result of the ordered structures frozen into the polyacrylamide hydrogel matrixs. So we can reveal the relationship between their structure and color, and furthermore permit a systematic exploration on magnetically induced self-assembling dynamics, colloidal crystallography which have important significance in the large-scale industrial production in the future.

Heavy metal leaching limits activated carbon from sewage sludge (referred as ACS) to be used for wastewater treatment. Cr and Cd leaching from ACS exceed the permitted values. The leaching content of Cr and Cd decrease much with depositing ACS with chitosan (CS),below the permitted values. This is mainly due to the bind of Cr and Cd with the much group –NH2 of CS. The effects of initial dye concentration, pH and contact time had been studied. The dye adsorbed can act as a supple complexion agent with increasing initial dye concentration, increase the affinity for Cr and Cd. For Cd, the amount leaching of CS/ACS or ACS remains content with pH.The amount leaching of Cr decreases when the pH from 1 to 5 and then increases above the pH of 6.0. The contact time has no important influence on the leaching contents of Cr or Cd.

The new technological process to form deep hole in relative thin panel by friction heat not only saves material, but also obtains workpieces with high performance. The thermal analysis about friction heat and force about friction forming hole is one of key technology problems. In this paper, the model of temperature field and stress field are observed with LS-DYNA based on dynamic two sliding friction pair coupling model structure, then the temperature changes of the workpiece under different conditions are studied. The mathematical model verified the correctness of the simulation in this paper, and laid a foundation for further research on deep hole process by friction heat.

It is difficult to identify whether the ECS of a engine can overcome the HEMP environment, and if there are influences existing, how it will be affected and what extent it can. On the basis of discussing the occurring mechanics and characteristics of HEMP, a route to study the effects of the engine ECS under HEMP environment has been researched. Through the simulation of the HEMP, a laboratory test has been designed and carried out, and the influence of the engine ECS under HEMP has been analyzed. The research indicated that the engine ECS is susceptibility to the HEMP, the main damage mode is soft and transiency damage, it can make the control signal confusion and can even result in the suspension of work, but it can not make permanent hard damage to the ECS, and there are no evidence to show that the HEMP can result in an accumulation damage to the tested engine ECS.

Based on the principle of a screw seal, a new type of seal consisting of a series of screw seals was developed and named as an axial pumping baffle seal. A theoretical analysis model was presented for such a seal which was developed to be used in nuclear coolant pumps. The feasibility of sealing high-pressure medium for such a seal had been proved. The variation of leakage rate and pressure distribution between a tooth and a sleeve with the number of seal stages and the geometrical parameters of screws was studied. The sealing mechanism was presented. The results showed that such a new seal maybe replace the first stage seal of a series mechanical seal used in a nuclear pump. When the number of screw seals is about 9, the reliability is ensured by the cooperation of the “attack” of the screw seal and the “defense” of the 180° sharp back bend.

Since almost large die surfaces are free-form surfaces, currently, these are almost manually implemented. In order to overcome this barrier, floating polishing is a feasible polishing technology. The contact friction between polishing disk and workpiece is a key problem of floating polishing technology. This paper tries to study the contact friction between polishing disk and workpiece with ANSYS analysis software. At first, the paper focuses on the contact friction between polishing disk and plane workpiece by ANSYS analysis software, then focuses on the contact friction between polishing disk and cylinder and sphere workpiece with the software. The analysis results show the hypothesis of full friction condition is feasible. The research results will be used for developing the floating polishing.

The aim is to modify the activated carbon from sewage sludge with γ-Al2O3 by sol-gel, investigate its performances on the SO2 adsorption and the desulfurization mechanisms in the presence of gaseous oxygen. The modification of the activated carbon from sewage sludge was carried out by adding γ-Al2O3 to improve the SO2 adsorption in a simulated flue gas. The results indicated that γ-Al2O3 porous membranes addition was very effective in promoting the BET area and pore volumes of the activated carbon from sewage sludge. γ-Al2O3 porous membranes in the presence of gaseous oxygen had much effect on the adsorption performance and benefited the SO2 adsorption capacity. The physically adsorbed adsorption took place first. And the following reactions should be occurring on the active sites (*) because of the specific pore construction, BET area and surface functional groups on γ-Al2O3/activated carbon from sewage sludge: (1)SO2 + *→SO2* , (2) O2 + *→O2* , (3)SO2* + O2* → SO3* , (4) 3SO3* + Al2O3 → Al2(SO4)3.