A model was developed to simulate a vehicle diaphragm spring clutch with the evaluation indicators of jerk degree and friction work.First,the pressing load characteristic of the driven plate of the diaphragm spring cl...A model was developed to simulate a vehicle diaphragm spring clutch with the evaluation indicators of jerk degree and friction work.First,the pressing load characteristic of the driven plate of the diaphragm spring clutch was analyzed.Then,the clutch dynamic characteristic under each state was studied according to the basic principles of tribology.Finally,the mathematical model of the clutch was developed.Based on the model,the performance of a vehicle was simulated.The simulation results show that the model can predict the dynamic characteristic of the clutch correctly and evaluate the performance of the clutch engagement effectively.The model can be used for theoretical research of automatic clutch control and can be easily applied to simulate vehicle longitudinal dynamics.展开更多
BACKGROUND： Pulmonary stretch reflex plays an important role in regulation of respiratorymovement. This study aimed to evaluate the effect of pulmonary stretch reflex on lung injury inrabbits with acute respiratory d...BACKGROUND： Pulmonary stretch reflex plays an important role in regulation of respiratorymovement. This study aimed to evaluate the effect of pulmonary stretch reflex on lung injury inrabbits with acute respiratory distress syndrome （ARDS）.METHODS： ARDS rabbits were given intratracheal infusion of hydrochloric acid and ventilatedwith neurally adjusted ventilatory assistance （NAVA） with a tidal volume （VT） of 6 mL/kg and theelectrical activity of diaphragm （EAdi）-determined positive end expiratory pressure. After isolation ofthe bilateral vagus nerve trunk, the rabbits were randomized into two groups： sham operation （SHAM）group （n=5） and bilateral vagotomy （VAG） group （n=5）. Gas exchange and respiratory mechanicswere detected at baseline, after lung injury and 1, 2, and 3 hours after ventilation respectively.Pulmonary permeability index, pathological changes and infl ammatory response were also measured.RESULTS： Compared with the SHAM group, PaO2/FiO2 in the VAG group decreased signifi cantly2 and 3 hours after ventilation （P〈0.05）. There was no significant difference in PaCO2 betweenthe SHAM and VAG groups （P〉0.05）, and the VAG group had a high VT, peak pressure （Ppeak）,and mean pressure （Pm） compared with the SHAM group 1, 2, 3 hours after ventilation （P〈0.05）.Compared to the SHAM group, dead space fraction （VD/VT） and respiratory system elastance （Ers）in the VAG group increased （P〈0.05） and static pulmonary compliance （Cst） decreased markedly（P〈0.05） after ventilation for 3 hours. Lung wet/dry weight ratio （W/D） （8.4±1.2 vs. 6.6±1.0）, lung injuryscore （6.3±1.8 vs. 3.8±1.3）, tumor necrosis factor-# （TNF-#） （779±372 pg/mL vs. 355±130 pg/mL）and interleukin-8 （IL-8） （169±21 pg/mL vs. 118±17 pg/mL） increased significantly in the VAG groupcompared with the SHAM group （P〈0.05）.CONCLUSION： Lung injury is aggravated after bilateral vagotomy, demonstrating thatpulmonary stretch refl ex may have protective effect on the lung.展开更多
The diaphragm spring clutch static characteristics to improve the starting quality for cars equipped with automated mechanical transmission （AMT） were modeled and simulated. First, axial stiffness of clutch cushion ...The diaphragm spring clutch static characteristics to improve the starting quality for cars equipped with automated mechanical transmission （AMT） were modeled and simulated. First, axial stiffness of clutch cushion spring and characteristic curves of diaphragm spring were theoretically and experimentally studied. Then, model of transfer characteristics of the normal force was built, with special conscen on the abrasion of friction discs and the influence of temperature to diaphragm spring. Finally, the model was tested in practical starting for cars equipped with AMT, which showed that the starting quality was significantly improved. The experimental results showed that the proposed model was precise enough to be implemented conveniently.展开更多
As one of the most important steps in wastewater treatment, limited study on plasma discharge process is a key challenge in the development of plasma applications. In this study, we focus on the plasma discharge proce...As one of the most important steps in wastewater treatment, limited study on plasma discharge process is a key challenge in the development of plasma applications. In this study, we focus on the plasma discharge process of a pulsed diaphragm discharge system. According to the analysis, the pulsed diaphragm discharge proceeds in seven stages： （1） Joule heating and heat exchange stage; （2） nucleated site formation; （3） plasma generation （initiation of the breakdown stage）; （4） avalanche growth and plasma expansion; （5） plasma contraction; （6） termination of the plasma discharge; and （7） heat exchange stage. From this analysis, a critical voltage criterion for breakdown is obtained. We anticipate this finding will provide guidance for a better application of plasma discharges, especially diaphragm plasma discharges.展开更多
This paper presents a novel anti-shock bulk silicon etching apparatus for solving a universal problem which occurs when releasing the diaphragm （e.g. SiNx）, that the diaphragm tends to be probably cracked by the imp...This paper presents a novel anti-shock bulk silicon etching apparatus for solving a universal problem which occurs when releasing the diaphragm （e.g. SiNx）, that the diaphragm tends to be probably cracked by the impact of heatinginduced bubbles, the swirling of heating-induced etchant, dithering of the hand and imbalanced etchant pressure during the wafer being taken out. Through finite element methods, the causes of the diaphragm cracking are analysed. The impact of heating-induced bubbles could be the main factor which results in the failure stress of the SiNx diaphragm and the rupture of it. In order to reduce the four potential effects on the cracking of the released diaphragm, an anti-shock hulk silicon etching apparatus is proposed for using during the last etching process of the diaphragm release. That is, the silicon wafer is first put into the regular constant temperature etching apparatus or ultrasonic plus, and when the residual bulk silicon to be etched reaches near the interface of the silicon and SiNx diaphragm, within a distance of 50-80μm （the exact value is determined by the thickness, surface area and intensity of the released diaphragm）, the wafer is taken out carefully and put into the said anti-shock silicon etching apparatus. The wafer＇s position is at the geometrical centre, also the centre of gravity of the etching vessel. An etchant outlet is built at the bottom. The wafer is etched continuously, and at the same time the etchant flows out of the vessel. Optionally, two symmetrically placed low-power heating resistors are put in the anti-shock silicon etching apparatus to quicken the etching process. The heating resistors＇ power should be low enough to avoid the swirling of the heating-induced etchant and the impact of the heating-induced bubbles on the released diaphragm. According to the experimental results, the released SiNx diaphragm thus treated is unbroken, which proves the practicality of the said anti-shock bulk silicon etching apparatus.展开更多
Typing of the muscular fibers in the costal and crural diaphragm (DIcos and DIcru) was undertaken with myosin ATPase histochemistry and the cross sectional area (CSA) of each fiber was measured with a computerized ima...Typing of the muscular fibers in the costal and crural diaphragm (DIcos and DIcru) was undertaken with myosin ATPase histochemistry and the cross sectional area (CSA) of each fiber was measured with a computerized image-processing system. It was found that the muscle fibers could be classified into types Ⅰ,ⅡA and ⅡB and they accounted for 33. 2%, 26. 9% and 39. 9% in DIcos and 25. 3%, 23. 1 % and 51. 6% in DIcru respectively. This indicated that there was difference of the proportion of each type of muscu1ar fibers between the two portions of the diaphragm. There is a higher percentage of slow-twitch oxidative fibers (type Ⅰ) in Dlcos and a higher percentage of fast-twitch glycolytic fibers (type ⅡB) in DIcru. The size of the same type of muscular fibers shows no significant difference between DIcos and DIcru.展开更多
This paper presents a case study on an ultra-deep diaphragm wall with a depth of 110 m constructed in Ningbo City. The in-situ application shows that using Bauer BC40 cutter machine in conjunction with cutter wheels s...This paper presents a case study on an ultra-deep diaphragm wall with a depth of 110 m constructed in Ningbo City. The in-situ application shows that using Bauer BC40 cutter machine in conjunction with cutter wheels specified for different strata would be qualified for constructing the 110 m diaphragm wall with high efficiency and precision given that the quality of slurry and poured concrete can be guaranteed. The ground settlement can be effectively controlled by using the overlapping construction method. Sliding failure as a whole characterized by pronounced lateral deformation is likely to occur in the upper muddy clay layer due to its high compressibility and sensitivity. In contrast, local collapse of trench walls tends to happen in the sandy silt strata. Furthermore, careful attention should be paid to sandy silt during the entire construction period as the vertical displacement of the sandy silt continues to develop even atter concrete pouring.展开更多
A simple gas-liquid diaphragm discharge reactor was designed and characteristics of the discharge and its application on decolorization of brilliant red B in an aqueous solution were investigated. The results showed t...A simple gas-liquid diaphragm discharge reactor was designed and characteristics of the discharge and its application on decolorization of brilliant red B in an aqueous solution were investigated. The results showed that strong oxidizing agents such as ·OH and ·O radicals were generated. Average electron temperature of the discharge was 0.72 eV, 1.15 eV and 0.83 eV with air, oxygen and argon as the discharge gas, respectively. Solution p H and conductivity changed little when oxygen or argon was used as the discharge gas; however, these two parameters changed significantly when the discharge was performed in air. During the discharge treatment,the characteristic absorption peaks of brilliant red B gradually decreased where the decolorization followed the first-order kinetics. With 10 min of discharge, the decolorization of brilliant red B（30 mg L^-1） can reach 96%, 81% and 62% in the cases of oxygen, argon and air,respectively. The analysis of by-products showed that the brilliant red B molecule can be effectively destroyed in this discharge mode.展开更多
A synergistic photocatalysis combined pulsed diaphragm discharge（PDD）system with TiO_2 nanofilm deposited on the surface of quartz diaphragm is developed for the first time for phenol degradation in an aqueous solut...A synergistic photocatalysis combined pulsed diaphragm discharge（PDD）system with TiO_2 nanofilm deposited on the surface of quartz diaphragm is developed for the first time for phenol degradation in an aqueous solution.It is observed that the decomposition efficiency of phenol in the TiO_2 combined PDD system is higher than that of the single PDD system under the same conditions,indicating a successful collaboration between the photocatalysis and the plasma decomposition in the present system.Analysis of the solution＇s pH value confirms this collaboration and further reveals that the photocatalytic enhancement effect of phenol degradation is strong at a relatively low supplied voltage.The present TiO_2 combined PDD system exhibits improved efficiencies of pollutant degradation and energy utilization,suggesting a good candidate for wastewater treatment.展开更多
A fiber Bragg grating （FBG） hydrophone with enhanced sensitivity is demonstrated. A novel piston-like diaphragm with a hard core fixed at the center is used as the sensing element. Theoretical analysis shows that th...A fiber Bragg grating （FBG） hydrophone with enhanced sensitivity is demonstrated. A novel piston-like diaphragm with a hard core fixed at the center is used as the sensing element. Theoretical analysis shows that the Young＇s modulus of the diaphragm and the radius of the hard core have significant effect on the pressure sensitivity. Experiments are carried out to test this effect and the performance of the hydrophone. The static measure- ment result is in good agreement with the theoretical result and an acoustic sensitivity of 7 nm/MPa has been achieved.展开更多
基金Supported by the National Natural Science Foundation of China(51375053)
文摘A model was developed to simulate a vehicle diaphragm spring clutch with the evaluation indicators of jerk degree and friction work.First,the pressing load characteristic of the driven plate of the diaphragm spring clutch was analyzed.Then,the clutch dynamic characteristic under each state was studied according to the basic principles of tribology.Finally,the mathematical model of the clutch was developed.Based on the model,the performance of a vehicle was simulated.The simulation results show that the model can predict the dynamic characteristic of the clutch correctly and evaluate the performance of the clutch engagement effectively.The model can be used for theoretical research of automatic clutch control and can be easily applied to simulate vehicle longitudinal dynamics.
文摘BACKGROUND： Pulmonary stretch reflex plays an important role in regulation of respiratorymovement. This study aimed to evaluate the effect of pulmonary stretch reflex on lung injury inrabbits with acute respiratory distress syndrome （ARDS）.METHODS： ARDS rabbits were given intratracheal infusion of hydrochloric acid and ventilatedwith neurally adjusted ventilatory assistance （NAVA） with a tidal volume （VT） of 6 mL/kg and theelectrical activity of diaphragm （EAdi）-determined positive end expiratory pressure. After isolation ofthe bilateral vagus nerve trunk, the rabbits were randomized into two groups： sham operation （SHAM）group （n=5） and bilateral vagotomy （VAG） group （n=5）. Gas exchange and respiratory mechanicswere detected at baseline, after lung injury and 1, 2, and 3 hours after ventilation respectively.Pulmonary permeability index, pathological changes and infl ammatory response were also measured.RESULTS： Compared with the SHAM group, PaO2/FiO2 in the VAG group decreased signifi cantly2 and 3 hours after ventilation （P〈0.05）. There was no significant difference in PaCO2 betweenthe SHAM and VAG groups （P〉0.05）, and the VAG group had a high VT, peak pressure （Ppeak）,and mean pressure （Pm） compared with the SHAM group 1, 2, 3 hours after ventilation （P〈0.05）.Compared to the SHAM group, dead space fraction （VD/VT） and respiratory system elastance （Ers）in the VAG group increased （P〈0.05） and static pulmonary compliance （Cst） decreased markedly（P〈0.05） after ventilation for 3 hours. Lung wet/dry weight ratio （W/D） （8.4±1.2 vs. 6.6±1.0）, lung injuryscore （6.3±1.8 vs. 3.8±1.3）, tumor necrosis factor-# （TNF-#） （779±372 pg/mL vs. 355±130 pg/mL）and interleukin-8 （IL-8） （169±21 pg/mL vs. 118±17 pg/mL） increased significantly in the VAG groupcompared with the SHAM group （P〈0.05）.CONCLUSION： Lung injury is aggravated after bilateral vagotomy, demonstrating thatpulmonary stretch refl ex may have protective effect on the lung.
基金Supported by the National Natural Science Foundation of China(51275038)
文摘The diaphragm spring clutch static characteristics to improve the starting quality for cars equipped with automated mechanical transmission （AMT） were modeled and simulated. First, axial stiffness of clutch cushion spring and characteristic curves of diaphragm spring were theoretically and experimentally studied. Then, model of transfer characteristics of the normal force was built, with special conscen on the abrasion of friction discs and the influence of temperature to diaphragm spring. Finally, the model was tested in practical starting for cars equipped with AMT, which showed that the starting quality was significantly improved. The experimental results showed that the proposed model was precise enough to be implemented conveniently.
基金supported by National Natural Science Foundation of China(Nos.11205202,21203204 and 11175214)Natural Science Foundation of Anhui Province,China (No.1308085QA09)
文摘As one of the most important steps in wastewater treatment, limited study on plasma discharge process is a key challenge in the development of plasma applications. In this study, we focus on the plasma discharge process of a pulsed diaphragm discharge system. According to the analysis, the pulsed diaphragm discharge proceeds in seven stages： （1） Joule heating and heat exchange stage; （2） nucleated site formation; （3） plasma generation （initiation of the breakdown stage）; （4） avalanche growth and plasma expansion; （5） plasma contraction; （6） termination of the plasma discharge; and （7） heat exchange stage. From this analysis, a critical voltage criterion for breakdown is obtained. We anticipate this finding will provide guidance for a better application of plasma discharges, especially diaphragm plasma discharges.
文摘This paper presents a novel anti-shock bulk silicon etching apparatus for solving a universal problem which occurs when releasing the diaphragm （e.g. SiNx）, that the diaphragm tends to be probably cracked by the impact of heatinginduced bubbles, the swirling of heating-induced etchant, dithering of the hand and imbalanced etchant pressure during the wafer being taken out. Through finite element methods, the causes of the diaphragm cracking are analysed. The impact of heating-induced bubbles could be the main factor which results in the failure stress of the SiNx diaphragm and the rupture of it. In order to reduce the four potential effects on the cracking of the released diaphragm, an anti-shock hulk silicon etching apparatus is proposed for using during the last etching process of the diaphragm release. That is, the silicon wafer is first put into the regular constant temperature etching apparatus or ultrasonic plus, and when the residual bulk silicon to be etched reaches near the interface of the silicon and SiNx diaphragm, within a distance of 50-80μm （the exact value is determined by the thickness, surface area and intensity of the released diaphragm）, the wafer is taken out carefully and put into the said anti-shock silicon etching apparatus. The wafer＇s position is at the geometrical centre, also the centre of gravity of the etching vessel. An etchant outlet is built at the bottom. The wafer is etched continuously, and at the same time the etchant flows out of the vessel. Optionally, two symmetrically placed low-power heating resistors are put in the anti-shock silicon etching apparatus to quicken the etching process. The heating resistors＇ power should be low enough to avoid the swirling of the heating-induced etchant and the impact of the heating-induced bubbles on the released diaphragm. According to the experimental results, the released SiNx diaphragm thus treated is unbroken, which proves the practicality of the said anti-shock bulk silicon etching apparatus.
文摘Typing of the muscular fibers in the costal and crural diaphragm (DIcos and DIcru) was undertaken with myosin ATPase histochemistry and the cross sectional area (CSA) of each fiber was measured with a computerized image-processing system. It was found that the muscle fibers could be classified into types Ⅰ,ⅡA and ⅡB and they accounted for 33. 2%, 26. 9% and 39. 9% in DIcos and 25. 3%, 23. 1 % and 51. 6% in DIcru respectively. This indicated that there was difference of the proportion of each type of muscu1ar fibers between the two portions of the diaphragm. There is a higher percentage of slow-twitch oxidative fibers (type Ⅰ) in Dlcos and a higher percentage of fast-twitch glycolytic fibers (type ⅡB) in DIcru. The size of the same type of muscular fibers shows no significant difference between DIcos and DIcru.
基金Funded by the National Basic Research Program of China(973 Program,No.2014CB046905)the National Natural Science Foundation of China(Grant Nos.41172249 and 51509186)+1 种基金the State Key Laboratory for Geomechanics and Deep Underground Engineering(No.SKLGDUEK1303)the funding provided by Zhuhai Da Heng Qin Company Limited(Grant No.SG25-2014-173B1)
文摘This paper presents a case study on an ultra-deep diaphragm wall with a depth of 110 m constructed in Ningbo City. The in-situ application shows that using Bauer BC40 cutter machine in conjunction with cutter wheels specified for different strata would be qualified for constructing the 110 m diaphragm wall with high efficiency and precision given that the quality of slurry and poured concrete can be guaranteed. The ground settlement can be effectively controlled by using the overlapping construction method. Sliding failure as a whole characterized by pronounced lateral deformation is likely to occur in the upper muddy clay layer due to its high compressibility and sensitivity. In contrast, local collapse of trench walls tends to happen in the sandy silt strata. Furthermore, careful attention should be paid to sandy silt during the entire construction period as the vertical displacement of the sandy silt continues to develop even atter concrete pouring.
基金supported by the Fundamental Research Funds for the Central Universities(3132016056)the Natural Science Foundation of Fujian province,China(No.2015J01651)National Natural Science Foundation of China(No.11005014)
文摘A simple gas-liquid diaphragm discharge reactor was designed and characteristics of the discharge and its application on decolorization of brilliant red B in an aqueous solution were investigated. The results showed that strong oxidizing agents such as ·OH and ·O radicals were generated. Average electron temperature of the discharge was 0.72 eV, 1.15 eV and 0.83 eV with air, oxygen and argon as the discharge gas, respectively. Solution p H and conductivity changed little when oxygen or argon was used as the discharge gas; however, these two parameters changed significantly when the discharge was performed in air. During the discharge treatment,the characteristic absorption peaks of brilliant red B gradually decreased where the decolorization followed the first-order kinetics. With 10 min of discharge, the decolorization of brilliant red B（30 mg L^-1） can reach 96%, 81% and 62% in the cases of oxygen, argon and air,respectively. The analysis of by-products showed that the brilliant red B molecule can be effectively destroyed in this discharge mode.
基金supported by National Natural Science Foundation of China(Nos.11205202,21203204 and 11175214)National Natural Science Foundation of Anhui Province(No.1308085QA09)
文摘A synergistic photocatalysis combined pulsed diaphragm discharge（PDD）system with TiO_2 nanofilm deposited on the surface of quartz diaphragm is developed for the first time for phenol degradation in an aqueous solution.It is observed that the decomposition efficiency of phenol in the TiO_2 combined PDD system is higher than that of the single PDD system under the same conditions,indicating a successful collaboration between the photocatalysis and the plasma decomposition in the present system.Analysis of the solution＇s pH value confirms this collaboration and further reveals that the photocatalytic enhancement effect of phenol degradation is strong at a relatively low supplied voltage.The present TiO_2 combined PDD system exhibits improved efficiencies of pollutant degradation and energy utilization,suggesting a good candidate for wastewater treatment.
基金supported by the National 863 Program under Grant No. 2007AA03Z415.
文摘A fiber Bragg grating （FBG） hydrophone with enhanced sensitivity is demonstrated. A novel piston-like diaphragm with a hard core fixed at the center is used as the sensing element. Theoretical analysis shows that the Young＇s modulus of the diaphragm and the radius of the hard core have significant effect on the pressure sensitivity. Experiments are carried out to test this effect and the performance of the hydrophone. The static measure- ment result is in good agreement with the theoretical result and an acoustic sensitivity of 7 nm/MPa has been achieved.
