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Development of Vibrating Monitoring for Hydro Power Turbines under Operating Condition

Journal of Mechanics Engineering and Automation 2014年第11期4卷 878-886页

作者： skvorcov oleg Department of Mechanical Engineering Institut of the Russian Academy of Sciense Moscow 101990 Russia

Units and components of the powerful power equipment are exposed to the big static and dynamic load. An example of such equipments is turbines hydraulic power plant and, especially, hydroelectric pumped storage power plant. Existing techniques of control of a vibrating condition do not consider： very wide frequency range of vibrating processes, difficult character of such processes in the form of the sum multiharmonic, random and close to shock processes. Such techniques usually do not consider intervals of start-up and stop, and also work on transitive modes when loadings on a construction are maximum. Available techniques of an estimation of admissible level of vibrating influence and tests for vibration durability are not harmonized enough among themselves. Various known interpretations of communication of vibrating characteristics and durability estimations on mechanical pressure at broadband vibrating influence yield ambiguous result. On the basis of the analysis of the published information, we attempt to formulate the requirement to system of vibrating monitoring of the hydraulic turbine and power motor pumps. System should provide data acquisition and the analysis of the data on a vibrating condition taking into account accumulation of vibrating influences and long term of operation on the basis of estimation methods as low-cycle, and high-cycle （gigacycle） fatigue is made.

关键词： Vibrating durability shock random transitive modes water-wheel acceleration velocity displacement pumped-storage

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Sex differences in cardiovascular control by nitric oxide in normotensive and hypertensive rats

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Health 2010年第8期2卷 897-905页

作者： Oxana Semyachkina-Glushkovskaya Tatyana Anishchenko Sergey Kapralov Roman Novikov Konstantin skvorcov Yana Kuznecova Antonina Kuznecova 不详

R Nitric oxide probably plays an important role in mechanisms determining sexual dimorphism in the development of cardiovascular diseases, including hypertension. Because stress together with gender are significant cardiovascular risk factors, we studied the role nitric oxide in car-diovascular regulation in male and female nor-motensive and hypertensive rats under normal and stress conditions. Experiments were per-formed in mongrel normotensive and hyperten-sive (two kidney, one clip) rats of both sexes, weighing 200-250g. The study of mean arterial pressure and heart rate was carried out: 1) under control condition;2) during nitric oxide blo- ckade by NG-nitro-L-arginine-methyl ester (L-NAME, 10 mg/kg, iv) 3) during 60 min immobilization stress and recovery;4) during 60 min immobi-lization stress + L-NAME and recovery. We found that the severity of hypertension in fe-males was lower than in males. We also ob-served that both normotensive and hyperten-sive females demonstrated more favorable pat-tern of cardiovascular responses to stress. At rest, nitric oxide blockade increased the mean arterial pressure and decreased the heart rate more effectively in female normotensive and hypertensive rats than in male groups. During stress, nitric oxide blockade modified the stress- induced cardiovascular responses more sig-nificantly in female normotensive and hyper-tensive rats compared with male groups. Our data show that both normotensive and hyper-tensive females demonstrated the more effec-tive nitric oxide control of cardiovascular activ-ity under normal and especially stress condi-tions than male groups. This male-female dif-ference may be important mechanism respon-sible for greater in females vs. males of cardio-vascular resistance to stress and development of hypertension.

关键词： Nitric Oxide Stress Cardiovascular Stress-Reactivity Sex-Differences

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