Geminal dinitropropyl ester plasticizers(DNPEPs) possess excellent energetic performances which provide good potentials as insensitive plasticizer. In this study, we design and synthesize DNPEPs with different alkane ...Geminal dinitropropyl ester plasticizers(DNPEPs) possess excellent energetic performances which provide good potentials as insensitive plasticizer. In this study, we design and synthesize DNPEPs with different alkane chain parts, and systematically investigate their structure-property relationships.Results show that DNPEPs have impact sensitivities all higher than 25.2 J, thermal decomposition temperatures all higher than 254 ℃, and glass transition temperatures(T_(g)) lower than-90 ℃.Furthermore, the effects of DNPEPs as plasticizer are studied on hydroxyl terminated polybutadiene(HTPB) in detail, including the viscosity, glass transition temperatures and others. It is noteworthy that 2,2-dinitropropyl nonanoate(DNPNc) among these DNPEPs exhibits the most expected simultaneous tuning effects on both viscosity and T_(g) of HTPB systems, providing favorable potentials to replace the conventional plastizers as dioctyl sebacate(DOS) in the HTPB based propellants and explosives.展开更多
During the oil production, in order to monitor the working conditions of an electrical submersible pump （ESP）,an electrical current recorder is used to monitor the electric motor current of an ESP. The recorder char...During the oil production, in order to monitor the working conditions of an electrical submersible pump （ESP）,an electrical current recorder is used to monitor the electric motor current of an ESP. The recorder charts indicate various working conditions of the ESP. Subtle malfunctions or abnormal problems of the ESP can be detected and further analyzed from various features of these current curves on the recording charts. Presently, these current charts are manually read and analyzed in oil fields. In this paper, a diagnosis expert system is presented for automatically analyzing these current recording charts and identifying the working condition of the ESP. This expert system includes an open knowledge base, which can be updated or enriched according to the identified features of the current curves on the recording charts, and a condition monitoring and failure pattern recognition method, which is called ＂pick-up method of feature of the recording chart＂, and can be correctly applied in most cases. It has been shown that this expert system can effectively improve the accuracy and efficiency of failure diagnosis and working condition monitoring of ESPs.展开更多
基金financial support of the National Natural Science Foundation of China (21875185)。
文摘Geminal dinitropropyl ester plasticizers(DNPEPs) possess excellent energetic performances which provide good potentials as insensitive plasticizer. In this study, we design and synthesize DNPEPs with different alkane chain parts, and systematically investigate their structure-property relationships.Results show that DNPEPs have impact sensitivities all higher than 25.2 J, thermal decomposition temperatures all higher than 254 ℃, and glass transition temperatures(T_(g)) lower than-90 ℃.Furthermore, the effects of DNPEPs as plasticizer are studied on hydroxyl terminated polybutadiene(HTPB) in detail, including the viscosity, glass transition temperatures and others. It is noteworthy that 2,2-dinitropropyl nonanoate(DNPNc) among these DNPEPs exhibits the most expected simultaneous tuning effects on both viscosity and T_(g) of HTPB systems, providing favorable potentials to replace the conventional plastizers as dioctyl sebacate(DOS) in the HTPB based propellants and explosives.
文摘During the oil production, in order to monitor the working conditions of an electrical submersible pump （ESP）,an electrical current recorder is used to monitor the electric motor current of an ESP. The recorder charts indicate various working conditions of the ESP. Subtle malfunctions or abnormal problems of the ESP can be detected and further analyzed from various features of these current curves on the recording charts. Presently, these current charts are manually read and analyzed in oil fields. In this paper, a diagnosis expert system is presented for automatically analyzing these current recording charts and identifying the working condition of the ESP. This expert system includes an open knowledge base, which can be updated or enriched according to the identified features of the current curves on the recording charts, and a condition monitoring and failure pattern recognition method, which is called ＂pick-up method of feature of the recording chart＂, and can be correctly applied in most cases. It has been shown that this expert system can effectively improve the accuracy and efficiency of failure diagnosis and working condition monitoring of ESPs.
