By the use of the 3/2 power law presented by Toba combined with the significant wave energy balance equation for wind wave, wind wave growth at a limited fetch is analytically investigated. The new wind wave growth re...By the use of the 3/2 power law presented by Toba combined with the significant wave energy balance equation for wind wave, wind wave growth at a limited fetch is analytically investigated. The new wind wave growth relations (WWGRs) are analytically derived with sheltering coefficient and wind drag coefficient as parameters. The geometrical average of observational values of sheltering coefficient and the arithmetic average of observational values of wind drag coefficient are applied to determine the new WWGRs. Comparisons with existing empirical WWGRs are made.展开更多
The analytical method (AM) for separation of composite waves is presented based on the Hilbert transform. It is applicable to both regular and irregular trains; of waves. The wave data series measured with two wave ga...The analytical method (AM) for separation of composite waves is presented based on the Hilbert transform. It is applicable to both regular and irregular trains; of waves. The wave data series measured with two wave gauges in the experiments are separated into two series of incident and reflected waves. Then, the reflection coefficient can be easily obtained. The arrival of reflected waves can also be detected for improvement of the accuracy of the reflection coefficient. The reflection performance of the physical model can be estimated exactly without calculation of wave height and phase difference. Numerical samples developed to test the method are proved to be accurate. Physical experiments are conducted and compared with Goda's method and satisfactory results are obtained.展开更多
Objective: To evaluate the safety and clinical efficacy of segmental radiofrequency ablation of pulmonary vein (PV) ostia for patients with refractory paroxysmal atrial fibrillation (AF) under multi-slice spiral ...Objective: To evaluate the safety and clinical efficacy of segmental radiofrequency ablation of pulmonary vein (PV) ostia for patients with refractory paroxysmal atrial fibrillation (AF) under multi-slice spiral computed tomography (MSCT) guidance before the procedure. Methods: A series of 58 consecutive patients with refractory paroxysmal AF were enrolled to undergo segmental radiofrequency ablation ofPV ostia. The 36 male and 22 female patients with mean age of (57.4±9.5) (32-79) years and no obvious organic heart disease. Before ablation, patients received MSCT to generate 3-dimentional image of the left atrium (LA) and proximal PVs. Patients then underwent segmental radiofrequency ablation ofPV ostia using PV circular mapping catheter manipulated several times to ensure complete isolation between PVs and LA. Results: No complications occurred during the procedure. One patient developed delayed cardiac tamponade, which was drained percutaneously. The mean follow-up time was (17.1±9.3) months. Forty-one patients (95%) experienced improved quality of life one month after the procedure. Thirty-six patients (83%) showed stable sinus rhythm, while 10 patients (23%) required additional anti-arrhythmic drugs. AF returned≥1 time in 6 (14%) patients who underwent anti-arrhythmic drug therapy, but the number of episodes was less than that before the procedure. However, one patient experienced recurrent episodes of atrial flutter. Conclusion: It is safe and effective to perform segmental radiofrequency ablation of PV ostia for patients with refractory paroxysmal AF using MSCT guidance mappening.展开更多
Affinity membrane was prepared with chitosan immobilized on the hydrophile- modified poly(vinylidene fluoride) (PVDF) membrane. Fourier transform infrared spectroscopy (FTIR.) analysis indicated that the contents of ...Affinity membrane was prepared with chitosan immobilized on the hydrophile- modified poly(vinylidene fluoride) (PVDF) membrane. Fourier transform infrared spectroscopy (FTIR.) analysis indicated that the contents of —NH2 and —OH groups increased and fluoride decreased on the membrane surface after modification. Using this kind of affinity membrane, the effects of operation parameters such as pH, ionic strength and flow rate, on the amount of endotoxin removed were investigated. The results showed that the equilibrium adsorption capacity and the dissociation constant of the affinity membrane to endotoxin were 21.4 EU·mg-1 membrane and 0.50EU·ml-1, respectively, at pH 7.0 and ionic strength 0.2 mol·L-1. Adsorption appeared to follow a typical Langmuir adsorption isotherm. At pH 5.0, ionic strength of 0.2 mol·L-1, the removal rate of endotoxin from BSA solution with the chitosan affinity membrane was up to 88.6% (11.50 EU·mg-1 membrane), and the recovery of BSA was 93.4% (0.187mg·mg-1 membrane), while at pH 11.0, ionic strength of 0.2mol·L-1, the removal rate of endotoxin from lysozyme solution was 72.4% (9.92EU·mg-1 membrane), and the recovery of lysozyme was 92.3% (0.104 mg·mg-1 membrane).展开更多
The reflection coefficient and the total horizontal forces of regular waves acting on theperforated caisson are experimentally investigated. The empirical relationship between reflection coefficient and the ratio of t...The reflection coefficient and the total horizontal forces of regular waves acting on theperforated caisson are experimentally investigated. The empirical relationship between reflection coefficient and the ratio of the total horizontal forces acting on the perforated caisson to those on solid vertical walls with the relative chamber width, relative water depth and porosity of perforated wall, etc. are given. Moreover, the results of the ratio of the total horizontal forces are also compared with formulas given by Chinese Harbour Design Criteria and Takahashi, which may be useful for the practical engineering application.展开更多
基金by the major state basic research program(No.G1999043809)the National Natural Science Foundation of China(No.40076003)the the Excellent Young Teachers Program of Ministry of Education,P.R.China(M.[2001]39)
文摘By the use of the 3/2 power law presented by Toba combined with the significant wave energy balance equation for wind wave, wind wave growth at a limited fetch is analytically investigated. The new wind wave growth relations (WWGRs) are analytically derived with sheltering coefficient and wind drag coefficient as parameters. The geometrical average of observational values of sheltering coefficient and the arithmetic average of observational values of wind drag coefficient are applied to determine the new WWGRs. Comparisons with existing empirical WWGRs are made.
基金This project was financially supported by the Trans-Century Training Program Fund for the Talent,Ministry of Education of China.
文摘The analytical method (AM) for separation of composite waves is presented based on the Hilbert transform. It is applicable to both regular and irregular trains; of waves. The wave data series measured with two wave gauges in the experiments are separated into two series of incident and reflected waves. Then, the reflection coefficient can be easily obtained. The arrival of reflected waves can also be detected for improvement of the accuracy of the reflection coefficient. The reflection performance of the physical model can be estimated exactly without calculation of wave height and phase difference. Numerical samples developed to test the method are proved to be accurate. Physical experiments are conducted and compared with Goda's method and satisfactory results are obtained.
文摘Objective: To evaluate the safety and clinical efficacy of segmental radiofrequency ablation of pulmonary vein (PV) ostia for patients with refractory paroxysmal atrial fibrillation (AF) under multi-slice spiral computed tomography (MSCT) guidance before the procedure. Methods: A series of 58 consecutive patients with refractory paroxysmal AF were enrolled to undergo segmental radiofrequency ablation ofPV ostia. The 36 male and 22 female patients with mean age of (57.4±9.5) (32-79) years and no obvious organic heart disease. Before ablation, patients received MSCT to generate 3-dimentional image of the left atrium (LA) and proximal PVs. Patients then underwent segmental radiofrequency ablation ofPV ostia using PV circular mapping catheter manipulated several times to ensure complete isolation between PVs and LA. Results: No complications occurred during the procedure. One patient developed delayed cardiac tamponade, which was drained percutaneously. The mean follow-up time was (17.1±9.3) months. Forty-one patients (95%) experienced improved quality of life one month after the procedure. Thirty-six patients (83%) showed stable sinus rhythm, while 10 patients (23%) required additional anti-arrhythmic drugs. AF returned≥1 time in 6 (14%) patients who underwent anti-arrhythmic drug therapy, but the number of episodes was less than that before the procedure. However, one patient experienced recurrent episodes of atrial flutter. Conclusion: It is safe and effective to perform segmental radiofrequency ablation of PV ostia for patients with refractory paroxysmal AF using MSCT guidance mappening.
基金Supported by the National Basic Research Program of China (No. 2003CB615706)
文摘Affinity membrane was prepared with chitosan immobilized on the hydrophile- modified poly(vinylidene fluoride) (PVDF) membrane. Fourier transform infrared spectroscopy (FTIR.) analysis indicated that the contents of —NH2 and —OH groups increased and fluoride decreased on the membrane surface after modification. Using this kind of affinity membrane, the effects of operation parameters such as pH, ionic strength and flow rate, on the amount of endotoxin removed were investigated. The results showed that the equilibrium adsorption capacity and the dissociation constant of the affinity membrane to endotoxin were 21.4 EU·mg-1 membrane and 0.50EU·ml-1, respectively, at pH 7.0 and ionic strength 0.2 mol·L-1. Adsorption appeared to follow a typical Langmuir adsorption isotherm. At pH 5.0, ionic strength of 0.2 mol·L-1, the removal rate of endotoxin from BSA solution with the chitosan affinity membrane was up to 88.6% (11.50 EU·mg-1 membrane), and the recovery of BSA was 93.4% (0.187mg·mg-1 membrane), while at pH 11.0, ionic strength of 0.2mol·L-1, the removal rate of endotoxin from lysozyme solution was 72.4% (9.92EU·mg-1 membrane), and the recovery of lysozyme was 92.3% (0.104 mg·mg-1 membrane).
基金The present work was financially supported by the Joint Fund of the National Natural Science Foundation of China the Hong Kong Science Research Bureau under contract No.49910161985 the Research Fund for the Development of Harbor Engineering Desig
文摘The reflection coefficient and the total horizontal forces of regular waves acting on theperforated caisson are experimentally investigated. The empirical relationship between reflection coefficient and the ratio of the total horizontal forces acting on the perforated caisson to those on solid vertical walls with the relative chamber width, relative water depth and porosity of perforated wall, etc. are given. Moreover, the results of the ratio of the total horizontal forces are also compared with formulas given by Chinese Harbour Design Criteria and Takahashi, which may be useful for the practical engineering application.