The electrical conductivity method was successfully applied as a new monitoring technique to monitor the corrosion and corrosion inhibition processes of zinc metal. Measurements of electrical conductivity at 20.0°...The electrical conductivity method was successfully applied as a new monitoring technique to monitor the corrosion and corrosion inhibition processes of zinc metal. Measurements of electrical conductivity at 20.0°C of three different corrosive solutions (HCl, NaOH, and NaCl) were performed with two different concentrations (0.10 and 1.00 M) containing zinc sheets in the absence and presence of four different concentrations of sodium lignosulfonate (1.0, 5.0, 10.0, and 20.0 mM). The analysis of curves that illustrates the changes in electrical conductivity of these solutions provides qualitative information about the strength of corrosion as well as the extent of corrosion inhibition behavior. The results obtained from electrical conductivity measurements revealed that sodium lignosulfonate was an effective corrosion inhibitor in acidic medium (for both 0.10 and 1.00 M HCl) in which it converted into lignosulfonic acid, but was less effective in salt and alkaline media.展开更多
In cooling process of Fe-Cr-Al alloy oxidized at 1 300 ℃, the effect of cooling speed and exposure time on oxide spalled area fraction and successive variety of the spalled region were studied by investigating evolve...In cooling process of Fe-Cr-Al alloy oxidized at 1 300 ℃, the effect of cooling speed and exposure time on oxide spalled area fraction and successive variety of the spalled region were studied by investigating evolvement of the thermally grown oxide using in-situ CCD monitoring technique. The results showed that oxide spallation can be restrained by controlling cooling speed and the critical temperature drop of spallation initiation which is closely related to the oxide thickness or exposure time, and the spallation process of a little region may be described in more detail as two routes： from the oxide/substrate interface micro-decohesion, micro-buckles, buckle spreading, buckle crack to spallation and from the interface micro-decohesion, micro-buckles, buckle crack and spallation to the residual oxide decohesion and spallation.展开更多
A novel high sensihtity, small-volume photothermal intheence detector has beenintroduced for capillap zone electrophoresis separation analysis. The utility of thes sdriulboconstecheque for momtomp chelating reachon of...A novel high sensihtity, small-volume photothermal intheence detector has beenintroduced for capillap zone electrophoresis separation analysis. The utility of thes sdriulboconstecheque for momtomp chelating reachon of light rare earth with tribromoarsenazo has beenreported.展开更多
A new approach is advanced based on wavelet transform in tandem with autoregressive technique. Wavelets and wavelet packets decompose dynamic signal into different bands and pro- vide multiresolution or multiscale vie...A new approach is advanced based on wavelet transform in tandem with autoregressive technique. Wavelets and wavelet packets decompose dynamic signal into different bands and pro- vide multiresolution or multiscale view of signal. Autoregressive technique possesses effective function for short data processing. The approach is abopted to analyse nonstationary vibration sig- nals of mining excavator. The results indicate that nonstationary operating condition can be moni- tored and diagnosed. Transient toothmeshing frequency and rotating speed are measured. Weak vibration signal of defective ball bearing is extracted from strong vibration of gearbox and diag- nosed successfully. This approach is effective for nonstationary condition monitoring and early di- agnosis of latent fault.展开更多
A comprehensive strength monitoring system used on a fixed jacket platform is presented in this paper. The long-term monitoring of W-11-4A platform achieved. Structural responses (strain and acceleration) at selected ...A comprehensive strength monitoring system used on a fixed jacket platform is presented in this paper. The long-term monitoring of W-11-4A platform achieved. Structural responses (strain and acceleration) at selected locations, as well as associated environmental parameters, have been obtained. The emphasis of the paper is placed on the system design, and the instrumentation and operation methodology employed in the monitoring of the structural responses. The performance of the system and the characteristic results obtained during its 13-month operation are also summarized.展开更多
A method of damage identification for engineering structures based on ambient vibration is put forward, in which output data are used only. Firstly, it was identification of the statistic parameters to associate with ...A method of damage identification for engineering structures based on ambient vibration is put forward, in which output data are used only. Firstly, it was identification of the statistic parameters to associate with the exterior excitation for undamaged structures. Then it was detection and location of the structural damages for damaged structures. The ambient identification method includes a theoretical model and numerical method. The numerical experiment results show the method is precise and effective. This method may be used in health monitoring for bridges and architectures.展开更多
文摘The electrical conductivity method was successfully applied as a new monitoring technique to monitor the corrosion and corrosion inhibition processes of zinc metal. Measurements of electrical conductivity at 20.0°C of three different corrosive solutions (HCl, NaOH, and NaCl) were performed with two different concentrations (0.10 and 1.00 M) containing zinc sheets in the absence and presence of four different concentrations of sodium lignosulfonate (1.0, 5.0, 10.0, and 20.0 mM). The analysis of curves that illustrates the changes in electrical conductivity of these solutions provides qualitative information about the strength of corrosion as well as the extent of corrosion inhibition behavior. The results obtained from electrical conductivity measurements revealed that sodium lignosulfonate was an effective corrosion inhibitor in acidic medium (for both 0.10 and 1.00 M HCl) in which it converted into lignosulfonic acid, but was less effective in salt and alkaline media.
基金Item Sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars
文摘In cooling process of Fe-Cr-Al alloy oxidized at 1 300 ℃, the effect of cooling speed and exposure time on oxide spalled area fraction and successive variety of the spalled region were studied by investigating evolvement of the thermally grown oxide using in-situ CCD monitoring technique. The results showed that oxide spallation can be restrained by controlling cooling speed and the critical temperature drop of spallation initiation which is closely related to the oxide thickness or exposure time, and the spallation process of a little region may be described in more detail as two routes： from the oxide/substrate interface micro-decohesion, micro-buckles, buckle spreading, buckle crack to spallation and from the interface micro-decohesion, micro-buckles, buckle crack and spallation to the residual oxide decohesion and spallation.
文摘A novel high sensihtity, small-volume photothermal intheence detector has beenintroduced for capillap zone electrophoresis separation analysis. The utility of thes sdriulboconstecheque for momtomp chelating reachon of light rare earth with tribromoarsenazo has beenreported.
文摘A new approach is advanced based on wavelet transform in tandem with autoregressive technique. Wavelets and wavelet packets decompose dynamic signal into different bands and pro- vide multiresolution or multiscale view of signal. Autoregressive technique possesses effective function for short data processing. The approach is abopted to analyse nonstationary vibration sig- nals of mining excavator. The results indicate that nonstationary operating condition can be moni- tored and diagnosed. Transient toothmeshing frequency and rotating speed are measured. Weak vibration signal of defective ball bearing is extracted from strong vibration of gearbox and diag- nosed successfully. This approach is effective for nonstationary condition monitoring and early di- agnosis of latent fault.
文摘A comprehensive strength monitoring system used on a fixed jacket platform is presented in this paper. The long-term monitoring of W-11-4A platform achieved. Structural responses (strain and acceleration) at selected locations, as well as associated environmental parameters, have been obtained. The emphasis of the paper is placed on the system design, and the instrumentation and operation methodology employed in the monitoring of the structural responses. The performance of the system and the characteristic results obtained during its 13-month operation are also summarized.
文摘A method of damage identification for engineering structures based on ambient vibration is put forward, in which output data are used only. Firstly, it was identification of the statistic parameters to associate with the exterior excitation for undamaged structures. Then it was detection and location of the structural damages for damaged structures. The ambient identification method includes a theoretical model and numerical method. The numerical experiment results show the method is precise and effective. This method may be used in health monitoring for bridges and architectures.
