The well-densified Ni3Al-0.5B-5Cr alloy was fabricated by self-propagation high-temperature synthesis and extrusion technique. Microstructure examination shows that the synthesized alloy has fine microstructure and co...The well-densified Ni3Al-0.5B-5Cr alloy was fabricated by self-propagation high-temperature synthesis and extrusion technique. Microstructure examination shows that the synthesized alloy has fine microstructure and contains Ni3Al, Al2O3, Ni3B and Cr3Ni2 phases. Moreover, the self-propagation high-temperature synthesis and extrusion lead to great deformation and recrystallization in the alloy, which helps to refine the microstructure and weaken the misorientation. In addition, the subsequent extrusion procedure redistributes the Al2O3 particles and eliminates the γ-Ni phase. Compared with the alloy synthesized without extrusion, the Ni3Al-0.5B-5Cr alloy fabricated by self-propagation high-temperature synthesis and extrusion has better room temperature mechanical properties, which should be ascribed to the microstructure evolution.展开更多
A novel extension diagnosis method was proposed for enhancing the diagnosis ability of the conventional dissolved gas analysis. Based on the extension theory a matter-element model was established for qualitatively an...A novel extension diagnosis method was proposed for enhancing the diagnosis ability of the conventional dissolved gas analysis. Based on the extension theory a matter-element model was established for qualitatively and quantitatively describing the fault diagnosis problem of power transformers. The degree of relation based on the dependent functions was employed to determine the nature and the grade of the faults in a transformer system. And the proposed method was verified with the experimental data. The results show that accuracy rate of the diagnosis method exceeds 90% and two kinds of faults can be detected at the same time.展开更多
Adding polypropylene(PP)fibers and coarse aggregates has become a popular way to enhance the strength and stability of the cemented tailings backfilling(CTB)body.It is essential to explore the influence of tailings-ag...Adding polypropylene(PP)fibers and coarse aggregates has become a popular way to enhance the strength and stability of the cemented tailings backfilling(CTB)body.It is essential to explore the influence of tailings-aggregate ratio and fiber content on the mechanical properties of CTB samples.The comprehensive tests of the unconfined compressive strength(UCS),slump and microstructure were designed,and the regression models were established to characterize the effect of the strength,ductility and fluidity.The results indicate that the tailings-aggregate ratio of 5:5 and PP fiber content of 0.5 kg/m^(3) are the optimum point considering the UCS,cracking strain,peak strain and post-peak ductility.The tailings-aggregate ratio is consistent with the unary quadratic to the UCS and a linear model with a negative slope to the slump.Microstructural analysis indicates that PP fiber tends to bridge the cracks and rod-mill sand to serve as the skeleton of the paste matrix,which can enhance the compactness and improve the ductility of the CTB.The results presented here are of great significance to the understanding and application of coarse aggregates and fibers to improve the mechanical properties of CTB.展开更多
In the present paper, the therapeutic effects of otopoint pellet pressing plus body acupuncture and simple body acupuncture for dysphagia and water drinking induced coughing are compared in 126 cases of pseudobulbar p...In the present paper, the therapeutic effects of otopoint pellet pressing plus body acupuncture and simple body acupuncture for dysphagia and water drinking induced coughing are compared in 126 cases of pseudobulbar paralysis who are randomly divided into treatment group (n=63) and control group (n=63). Main acupoints used are Shuigou (GV 26), Fengchi (GB 20), Lianquan (CV 23) and Sanyinjiao (SP 6), while otopoints used are Xin (MA IC), Gan (MA SC 5), Pi (MA IC), Shen (MA SC), Yanhou (MA T 3) and She (MA L). Following one course of treatment (12 sessions), in treatment group, of the 63 cases, 34 (54.0%) are cured, 18 (28.5%) have remarkable improvement, 5 (8.0%) have improvement, and 6 ( 9.0%) have no apparent changes, with the tottal effective rate being 90.5%; while in control group, of the 63 cases, 18 (28.5%) are cured, 11 (17.5%) have marked amelioration, 15 ( 24.0%) experience apparent amelioration and 19 (30.0%) have no obvious changes, with a total effective rate of 70.0%. The therapeutic effect of otopoint pellet pressing plus body acupuncture is significantly superior to that of simple body acupuncture in the treatment of dysphagia and water drinking induced coughing.展开更多
Objective： This article introduces the concepts of mobile information technology and continuous care, develops a systematic review of the application of mobile information technology for continuous care in patients w...Objective： This article introduces the concepts of mobile information technology and continuous care, develops a systematic review of the application of mobile information technology for continuous care in patients with hypertension from three aspects： mobile communication technology, internet technology, health management platform, and puts forward the existing questions, influence and the research prospect of the application of mobile information tech- nology using in hypertension continuous care, in order to provide evidence for the application of mobile information technology in continuous care for hypertension patients in clinical practice.展开更多
Because of the difficulties of describing the process of combustion of underground mine fires, usually the fire seat is considered as a fixed point in the methods of mine fire computer simulation, however this is not ...Because of the difficulties of describing the process of combustion of underground mine fires, usually the fire seat is considered as a fixed point in the methods of mine fire computer simulation, however this is not in keeping with the feature of the distribution of the combustibles and the process of combustion in mine fires. A conception about movable linear fire seat is put forward first by the authors, together with the calculated models of the thermal decomposition rate, flame spreading velocity and the steady burning length of a linear fire seat etc. The paper also introduces the results of the application of these models.展开更多
In this study, austenitizing heat treatment before hot stamping of Al-10% Si coated boron steel is first investigated through en- vironment scanning electron microscopy （ESEM） equipped with energy dispersive x-ray a...In this study, austenitizing heat treatment before hot stamping of Al-10% Si coated boron steel is first investigated through en- vironment scanning electron microscopy （ESEM） equipped with energy dispersive x-ray analysis （EDAX）. The cracking be- havior of the coating was evaluated using Gleeble 3500, a thermo-mechanical simulator under uniaxial plastic deformation at elevated temperatures. The extent and number of cracks developed in the coating were carefully assessed through an optical microscope. The coating layer under hot-dipped condition consists of an Al-Si eutectic matrix, Fe2Al7Si, Fe3Al2Si3 and Fe2Al5, from the coating surface to the steel substrate. The coating layer remains dense, continuous and smooth. During austenitization, the Al-rich Fe-Al intermetallics in the coating transform to more Fe-rich intermetallics, promoted by the Fe diffusion process. The coating finally shows the coexistence of two types of Fe-Al intermetallics, namely, FeAl2 and FeAl. Microcracks and Kirkendall voids occur in the coating layer and diffusion zone, respectively. The coating is heavily cracked and broken into segments during the hot tensile tests. Bare steel exposed between the separate segments of the coating is oxidized and covered with a thin FeOx layer. The appearance of the oxide decreases the adhesion of the Al-Si coating. It is found that the ductile FeAl is preferred as a coating microstructure instead of the brittle FeAl2. Therefore, the ductility of the Al-Si coating on hot stamping boron steer could be enhanced by controlling the ductile Fe-rich intermetallic phase transformations within it during austenitization. Experiments indicate that a higher austenitizing temperature or longer dwell time facilitate the Fe-rich inter- metallics transformation, increasing the volume fraction of FeAl. This phase transformation also contributes to reducing the crack density and depth.展开更多
基金Project (2012CB933600) supported by the National Basic Research Program of ChinaProject (2011AA030104) supported by the National High-tech Research and Development Program of ChinaProject (JC200903170498A) supported by the Science and Technology Research Foundation of Shenzhen Bureau of Science and Technology & Information, China
文摘The well-densified Ni3Al-0.5B-5Cr alloy was fabricated by self-propagation high-temperature synthesis and extrusion technique. Microstructure examination shows that the synthesized alloy has fine microstructure and contains Ni3Al, Al2O3, Ni3B and Cr3Ni2 phases. Moreover, the self-propagation high-temperature synthesis and extrusion lead to great deformation and recrystallization in the alloy, which helps to refine the microstructure and weaken the misorientation. In addition, the subsequent extrusion procedure redistributes the Al2O3 particles and eliminates the γ-Ni phase. Compared with the alloy synthesized without extrusion, the Ni3Al-0.5B-5Cr alloy fabricated by self-propagation high-temperature synthesis and extrusion has better room temperature mechanical properties, which should be ascribed to the microstructure evolution.
文摘A novel extension diagnosis method was proposed for enhancing the diagnosis ability of the conventional dissolved gas analysis. Based on the extension theory a matter-element model was established for qualitatively and quantitatively describing the fault diagnosis problem of power transformers. The degree of relation based on the dependent functions was employed to determine the nature and the grade of the faults in a transformer system. And the proposed method was verified with the experimental data. The results show that accuracy rate of the diagnosis method exceeds 90% and two kinds of faults can be detected at the same time.
基金Project(51722401)supported by the National Science Foundation for Excellent Young Scholars of ChinaProject(51334001)supported by the Key Program of National Natural Science Foundation of ChinaProject(FRF-TP-18-003C1)supported by the Fundamental Research Funds for the Central Universities,China。
文摘Adding polypropylene(PP)fibers and coarse aggregates has become a popular way to enhance the strength and stability of the cemented tailings backfilling(CTB)body.It is essential to explore the influence of tailings-aggregate ratio and fiber content on the mechanical properties of CTB samples.The comprehensive tests of the unconfined compressive strength(UCS),slump and microstructure were designed,and the regression models were established to characterize the effect of the strength,ductility and fluidity.The results indicate that the tailings-aggregate ratio of 5:5 and PP fiber content of 0.5 kg/m^(3) are the optimum point considering the UCS,cracking strain,peak strain and post-peak ductility.The tailings-aggregate ratio is consistent with the unary quadratic to the UCS and a linear model with a negative slope to the slump.Microstructural analysis indicates that PP fiber tends to bridge the cracks and rod-mill sand to serve as the skeleton of the paste matrix,which can enhance the compactness and improve the ductility of the CTB.The results presented here are of great significance to the understanding and application of coarse aggregates and fibers to improve the mechanical properties of CTB.
文摘In the present paper, the therapeutic effects of otopoint pellet pressing plus body acupuncture and simple body acupuncture for dysphagia and water drinking induced coughing are compared in 126 cases of pseudobulbar paralysis who are randomly divided into treatment group (n=63) and control group (n=63). Main acupoints used are Shuigou (GV 26), Fengchi (GB 20), Lianquan (CV 23) and Sanyinjiao (SP 6), while otopoints used are Xin (MA IC), Gan (MA SC 5), Pi (MA IC), Shen (MA SC), Yanhou (MA T 3) and She (MA L). Following one course of treatment (12 sessions), in treatment group, of the 63 cases, 34 (54.0%) are cured, 18 (28.5%) have remarkable improvement, 5 (8.0%) have improvement, and 6 ( 9.0%) have no apparent changes, with the tottal effective rate being 90.5%; while in control group, of the 63 cases, 18 (28.5%) are cured, 11 (17.5%) have marked amelioration, 15 ( 24.0%) experience apparent amelioration and 19 (30.0%) have no obvious changes, with a total effective rate of 70.0%. The therapeutic effect of otopoint pellet pressing plus body acupuncture is significantly superior to that of simple body acupuncture in the treatment of dysphagia and water drinking induced coughing.
文摘Objective： This article introduces the concepts of mobile information technology and continuous care, develops a systematic review of the application of mobile information technology for continuous care in patients with hypertension from three aspects： mobile communication technology, internet technology, health management platform, and puts forward the existing questions, influence and the research prospect of the application of mobile information tech- nology using in hypertension continuous care, in order to provide evidence for the application of mobile information technology in continuous care for hypertension patients in clinical practice.
文摘Because of the difficulties of describing the process of combustion of underground mine fires, usually the fire seat is considered as a fixed point in the methods of mine fire computer simulation, however this is not in keeping with the feature of the distribution of the combustibles and the process of combustion in mine fires. A conception about movable linear fire seat is put forward first by the authors, together with the calculated models of the thermal decomposition rate, flame spreading velocity and the steady burning length of a linear fire seat etc. The paper also introduces the results of the application of these models.
基金supported by the National Natural Science Foundation of China(Grant No.51275185)the National Basic Research Program of China("973"Program)(Grant No.2010CB630802-3)
文摘In this study, austenitizing heat treatment before hot stamping of Al-10% Si coated boron steel is first investigated through en- vironment scanning electron microscopy （ESEM） equipped with energy dispersive x-ray analysis （EDAX）. The cracking be- havior of the coating was evaluated using Gleeble 3500, a thermo-mechanical simulator under uniaxial plastic deformation at elevated temperatures. The extent and number of cracks developed in the coating were carefully assessed through an optical microscope. The coating layer under hot-dipped condition consists of an Al-Si eutectic matrix, Fe2Al7Si, Fe3Al2Si3 and Fe2Al5, from the coating surface to the steel substrate. The coating layer remains dense, continuous and smooth. During austenitization, the Al-rich Fe-Al intermetallics in the coating transform to more Fe-rich intermetallics, promoted by the Fe diffusion process. The coating finally shows the coexistence of two types of Fe-Al intermetallics, namely, FeAl2 and FeAl. Microcracks and Kirkendall voids occur in the coating layer and diffusion zone, respectively. The coating is heavily cracked and broken into segments during the hot tensile tests. Bare steel exposed between the separate segments of the coating is oxidized and covered with a thin FeOx layer. The appearance of the oxide decreases the adhesion of the Al-Si coating. It is found that the ductile FeAl is preferred as a coating microstructure instead of the brittle FeAl2. Therefore, the ductility of the Al-Si coating on hot stamping boron steer could be enhanced by controlling the ductile Fe-rich intermetallic phase transformations within it during austenitization. Experiments indicate that a higher austenitizing temperature or longer dwell time facilitate the Fe-rich inter- metallics transformation, increasing the volume fraction of FeAl. This phase transformation also contributes to reducing the crack density and depth.
