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The uncertainty contribution related to linearity shall be considered in the calculation of measurement uncertainty when using the impulse voltage measuring system. Under the condition that the national standard is not yet established at present, the paper proposed an experimental method to measure the linearity of 600kV damped capacitive impulse divider (HCR600). The paper used low voltage resistance divider R200S to measure the linearity of generator, and obtained the linearity curve. With the increase of charging voltage, the linearity of divider can be obtained by measuring the charging voltage of impulse voltage generator precisely and its ratio of indicating value of the sample divider HCR600 after corrected. The result shows that the linearity of HCR600 decreases from +0.4% to-0.8%; the maximum difference between positive polarity and negative polarity is 0.14% and the linearity of negative polarity is superior to that of positive polarity. Besides, the paper used a 500kV resistance divider (SMR 7.7/ref500) calibrated by PTB to compare with HCR600, and obtained the linearity curve. By comparison, two curves show a good agreement, the maximum difference between them is 0.15% at the same voltage. The result shows that the method proposed in the paper can be used to measure the linearity of divider accurately. It also can be used as experimental verification in the process of the national standard establishing and to calibrate the ultrahigh voltage impulse voltage measuring equipments when equipments satisfy some requirements.

A measurement system used for step response of impulse voltage dividers has been designed. This software can be used for various kinds of step response waveforms and can calculate them accurately. The calculation methods used in this system are in full compliance with the requirements in DL/T992-2006 and IEC60060-2. When the software used for the step response of impulse divider,the calculation results meet the requirements of stepwave response parameters with good accuracy. This software is simple to calculate and it can greatly enhance the efficiency of the step response parameter extraction calculations.

Co3O4/NiO nanocomposite films were electrochemically synthesized on a ITO surface. The Co3O4/NiO nanocomposite films were characterized by energy-dispersive X-ray analysis (EDS) and scanning electron microscopy (SEM). The electrochromic properties of Co3O4/NiO nanocomposite films are investigated in an aqueous alkaline electrolyte (0.1M KOH) by means of transmittance, cyclic voltammetry (CV) and chronoamperometry (CA) measurements. The Co3O4/NiO nanocomposite films exhibit a noticeable electrochromism with reversible color changes, and fast switching speed (4.1 s and 3.6 s).

A finite volume method for the numerical solution of viscoelastic flows is given. The flow of a differential Phan-Thien-Tanner (PTT) fluid through an abrupt expansion-contraction channel has been chosen as a prototype example. Through the results of numerical simulations, the contours of velocity and stream function are drawn. Numerical results show that the viscoelasticity of polymer solutions is the main factor influencing the sweep efficiency. With increasing elasticity, the flowing area in the channel is enlarged significantly, thus the area with immobile zones becomes smaller, the microcosmic sweep efficiency increases. The visco-elastic nature of the displacing polymer fluids can ingeneral improve the displacement efficiency in pores compared to using Newtonian fluids. This conclusion should be useful in selecting polymer fluids and designing polymer flooding operations.

A 2D current and water quality model was set up with Delft3D-FLOW in this research, which was well calibrated and verified with the observed tidal levels and velocities. Considered with the project of the Qingcaosha Water Source, Pollution concentration distribution caused by sewage outfalls in the south bank of the Yangtze River during a neap tide of dry season is simulated and the computed results show: a high pollution zone appears near the south shore, and moves upward with flood flow and downward with ebb flow, however, it is bounded a limit region around the outfalls. During the tidal period, the water quality of the Qingcaosha water source can be classified as the second class water, which can ensure the normal water supply as the Shanghai water source. It is suggested that the regular monitoring water quality in this high pollution zone should be put into practice to ensure the water quality of water sourecs. The Yangtze River is adjacent to the East Sea and it’s the largest river in China, with obvious seasonal variant runoff and tidal flow. The Yangtze River was bifurcated by Chongming Island to south and north branch from Xuliujing, most of the flow go down through the south branch. The south branch was divided into south and north channel by Changxing Island and Hengsha Island. The south channel was bifurcated by Jiuduansha Shoal to south and north passage, three bifurcation areas and four estuarine outlets were formed (see Fig 1.)

The Qi-Great Wall tunnel which crossed the Qi -Great Wall ruins was a large span double-arch tunnel with two-way and six-lane and the maximum depth was less than 5 meters, in order to protect the safety of thr surface ruins in the tunnel construction progress, surface subsidence control was particularly important. Through comprehensive geomechanical model test and numerical simulation , the surface subsidence wich generated in the process of construction according to construction methods of excavation and support was studied, the distribution of surface subsidence got through two methods was fitted well,and research results could provide guidance for the construction.

Pickle is normally served as a side dish with the main meal or used as an appetizer and also favored by many Chinese. However, the accumulation of nitrite is a common problem faced during many vegetables fermentations. Effects of different fermentation conditions on the nitrite concentration were investigated during the preparation of lactobacillus pickles by using the modern biological technology. The results showed that the salt, lactobacillus preparation and some accessories could reduce the nitrite content during the carrot-pickles fermentation, and improve the safety of lactobacillus preparation pickles.