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To study the creep and aging behavior under the combined effect of temperature, humidity and static load, polyurethane adhesive was selected to make butt joints. The creep properties of the joint were analyzed experimentally under different static loads in hygrothermal environment. At the same time, an aging test under the combined effect of temperature, humidity and static load was carried out, and the variation law of the residual strength of the joint with the load and loading time was obtained. The complex fracture behavior of polyurethane adhesive joints was studied from macro to microscale. The results show that the hygrothermal environment had a significant effect on the creep properties of polyurethane adhesive joints. The creep strain rate of the joint was significantly higher, and the failure fracture time was shorter in the high temperature and humidity environment. When the temperature, humidity and static load were coupled, the joint failure strength decreased with time. With increasing load, the decline rate of the failure strength increased significantly. The interface failure of the joints and the hydrolysis reaction of the polyurethane adhesive were the main reasons for reducing the failure strength. [ABSTRACT FROM AUTHOR]

In order to study the pyrolysis behavior of Lycium barbarum L. polysaccharide and influence on the cigarette sensory quality, the polysaccharide was extracted by water extraction and alcohol precipitation method. The pyrolysates were analyzed in different atmosphere (10% O2 and 90% N2) and at temperature levels (300 °C,600 °C, 750 °C and 900 °C). The pyrolysates were directly introduced into Py-GJ-C-MS spectrometer, quantitative analysis was made by area normalization. The results showed that cigarette sensory quality was improved by polysaccharide, the smoke of cigarette was mild and glomerate, polysaccharides offered enhanced sweety aroma, as well as the aroma quantity, improve after-tasting and reduce offensive taste and irritation of cigarette. The optimum application amount was (5~10) x 10-6 g. The pyrolysis of polysaccharide could release micromolecule aldehydes and ketones containing special odor having floral, toast, sweet, milk and fruity notes. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the impact of resveratrol on coronary collateral circulation in pigs suffered from experimental acute coronary occlusion., Methods: Eighteen healthy pigs were randomly divided into 3 groups: resveratrol group, nitroglycerin group and control group. Animal model of acute coronary occlusion was established through PTCA method, and the blood flow spectrum in the left circumflex artery (LCX) was detected using intracoronary Doppler ultrasound., Results: The average peak velocity (APV) in infarction correlation artery (IRA) was significantly decreased immediately after coronary occlusion [(0.85 ± 0.25) cm/s vs. (24.83 ± 3.43) cm/s, P < 0.05]. The APV remained unchanged during 0, 30 and 60 minutes after the occlusion. Reversed or bidirectional blood flow was observed and the APV increased significantly [(9.22 ± 0.80) cm/s vs. (0.84 ± 0.21) cm/s, (8.93 ± 1.28) cm/s vs. (0.86 ± 0.26) cm/s respectively, P < 0.05] after the coronary injection of resveratrol (2 mg) or nitroglycerin (0.3 mg). There was no significant difference in peak APV between the resveratrol and nitroglycerin groups. The duration of increased APV was significantly longer in resveratrol group than that in nitroglycerin group [(58.83 ± 6.15) min vs. (21.80 ± 5.79) min, P < 0.05]., Conclusions: The collateral circulation after acute coronary occlusion was obviously insufficient in pigs. Resveratrol could significantly improve the blood flow in coronary collateral circulation after acute occlusion in this model.