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The focus of the study was to establish an UPLC-ESI-MS/MS method for the qualitative and quantitative determination of VLPVPR in rat plasma. The method was as follows: Protein impurities in the rat plasma samples were precipitated with methanol; A Waters Acquity BEH C18 column (100 mm×2.1 mm, 1.7 μm) was adopted; the column temperature was 25°C; the mobile phase consisted of methanol-water with gradient elution at the steady flow rate of 0.3 mL·min-1; the detection wavelength was 202 nm. Mass spectrometry applied selected ion monitoring mode with m/z 255 (quantitative ion) and m/z 169 (qualitative ion). It was found that excellent linear relationship was obtained from the range of 10~200 ng·mL-1 (r=0.9991), the limit determination (LOD) of VLPVPR was 1.8 ng·mL-1, the recovery rate was 96.33%~100.76%, The inter and intre-day RSD were less than 7%. We thus conclude that a rapid and sensitive UPLC-ESI-MS/MS method was developed and validated for the determination of recombinant antihypertensive peptide VLPVPR in rat plasma. It can be applied to evaluate the pharmacokinetics of VLPVPR.

Facial region detection has broad application prospects, but existing human face region detection methods have some rigorous requirements for the light conditions. Error detection about face area caused by the poor light conditions has a great bad effect on the follow-up processing, such as face recognition, fatigue degree evaluation based on visual. So face region detection in complex lighting conditions has always been the difficult problem. Therefore a self-adaptive illumination compensation method for color images has been proposed. Select the color face images database of the California Institute of Technology to test the method dealing with the face region detection by original image and the image after illumination compensation. In the simulation experiment, the method of Illumination compensation can effectively improve the detection accuracy. Lay the foundation for driver fatigue detection based on visual.

Under drip irrigation, the drip discharge has a great influence on soil water movement and crop growth. Studying the soil water movement rules makes great realistic significance to the precise management. Based on soil dynamics theory, we measured the water movement distance of saline soil in Changji Xinjiang through outdoor tests. Then, we built transfer function models between drip discharge and water movement distance under drip irrigation and applied the genetic algorithm to identifying and optimizing model’s parameters. Comparing the soil water movement model’s dynamic change at the same drip discharge, the model’s validity is validated. It can solve the feedback adjusting according to crop root, and the waste of water resource is reduced.

In the WEB2.0 environment, the report of public events will appear on the Internet as soon as they occur and attract a large number of peoples attention in a very short time. It is believed that the Internet public opinion represents the social public opinion. Hence, it is very valuable to study the relationship between the Internet public opinion and mass emergencies. In this paper, we proposed an improved effect model of the Internet public opinion spreading on mass emergencies. Different from the original model, we use variables as the parameters of the equation instead of constants and the whole mass emergency is divided into five stages. In the first two stages, the new participants proportion u(t) and the new leavers proportion v(t) holds the inequality u(t)≥v(t), and in the other stages, they hold u(t)≤v(t). Simulations show that the design of our proposed model can well fit the mass emergency development process.

Electrical resistance tomography (ERT) has been used as an alternative technique to monitor two-phase flow because of its high temporal resolution for monitoring fast transient processes. However the image reconstruction image with ERT in microchannel suffers from poor quality because of the interference of contact resistance. This paper aims at the solid-liquid two phase flow visualization in the cross-sections of a novel microchannel based on the ERT technique. Preliminary experimental results reveal that ERT image reconstruction technique base on Agilent data acquisition system can effectively detect the particle distribution in the microchannel.

Based on different aromatic dibromides and diamines, using Material Studio software and molecular simulation method, Poly(imino ketone) (PIK), Poly(imino ketone ketone) (PIKK), Poly(imino imino ketone) (PIIK), Poly(imino imino ketone ketone) (PIIKK), Flourene-PIIK and Naphthyl-PIIK, respectively, were designed as six different structures of polymers. And through the method of molecular mechanics and molecular dynamics the single-molecule polymer chain model and the aggregation-state model with three-dimensional periodic boundary conditions would be built. Theoretically, the established model has been verified availably after optimization based on molecular mechanics and molecular dynamics.

The shape, size and packing structure of the hydration products in the plain and fly ash (FA) cement pastes were conducted by the atomic force microscope (AFM). The water-binder ratio was 0.35, two cement pastes was plain cement as control and FA replacing 30% cement by mass, and the curing ages were adopted the 7 days and 90 days respectively. The results show that there are many round particles about 80nm. However, the size of the round particles has been tended to become smaller with the curing time increase. But the packing structure became tight because of the rearranged particle with the curing time increase. Moreover, fly ash would affect markedly the shape, size and packing structure of hydration products. The results indicate that C-S-H clusters in FA cement paste appear the flat shape and looser packing structure due to its low calcium and silicate ratio.

The physical, mechanics, deformation, heat properties, pore structure of foamed concrete with polypropylene fiber and high volume fly ash were tested with the different water/binder ratio, perlite, foaming agent, polycarboxylate water reducer. The results showed that when adding foaming agent, PCA into foamed concrete with lower W/B ratio, it is possible to research the function integration foamed concrete with lower bulk density, higher compressive strength, smaller drying shrinkage, thermal insulation and waterproof.