To improve the electrorheological effect of electrorheological fluid (ERF), a new type of the electrosensitive particle material, polynaphthalene quinone was prepared, whose molecules contain blended atoms of nitrogen...To improve the electrorheological effect of electrorheological fluid (ERF), a new type of the electrosensitive particle material, polynaphthalene quinone was prepared, whose molecules contain blended atoms of nitrogen, oxygen, sulphur and big π bond conjugate system. In both DC and AC electric fields, the ERF material showed a distinct ER effect. Especially, in the alternating electric field, the shear stress of this material versus AC voltage has a better quadratic relation than that of the other materials. The experimental data showed that organic semiconductor polymers with big π bond conjugate system are a new type of electrosensitive particle materials which are worth well developing.展开更多
Cyclic total reflux(CTR) batch distillation is a promising mode of the process but lacking of appropriate modeling for the period of filling the reflux drum.A new dynamic modeling method for the simulation of CTR batc...Cyclic total reflux(CTR) batch distillation is a promising mode of the process but lacking of appropriate modeling for the period of filling the reflux drum.A new dynamic modeling method for the simulation of CTR batch distillation is proposed in this work,in which the changes in column holdup and liquid flow rate during the filling of the drum,and the consequent change in valid number of theoretical plates are considered.The effect of drum holdup on operation time is investigated and the optimal drum holdup is obtained from the simulation.The dynamic modeling is compared to the conventional modeling without consideration of change in liquid flow rate. The experimental result shows that the present modeling is more reliable and more accurate,especially for the column with large liquid holdup.展开更多
AIM:To investigate the prevalence of gastroesophageal reflux disease(GERD) in patients with a laryngoscopic diagnosis of laryngopharyngeal reflux(LPR).METHODS:Between May 2011 and October 2011,41 consecutive patients ...AIM:To investigate the prevalence of gastroesophageal reflux disease(GERD) in patients with a laryngoscopic diagnosis of laryngopharyngeal reflux(LPR).METHODS:Between May 2011 and October 2011,41 consecutive patients with laryngopharyngeal symptoms(LPS) and laryngoscopic diagnosis of LPR were empirically treated with proton pump inhibitors(PPIs) for at least 8 wk,and the therapeutic outcome was assessed through validated questionnaires(GERD impact scale,GIS;visual analogue scale,VAS).LPR diagnosis was performed by ear,nose and throat specialists using the reflux finding score(RFS) and reflux symptom index(RSI).After a 16-d wash-out from PPIs,all patients underwent an upper endoscopy,stationary esophageal manometry,24-h multichannel intraluminal impedance and pH(MII-pH) esophageal monitoring.A positive correlation between LPR diagnosis and GERD was supposed based on the presence of esophagitis(ERD),pathological acid exposure time(AET) in the absence of esophageal erosions(NERD),and a positive correlation between symptoms and refluxes(hypersensitive esophagus,HE).RESULTS:The male/female ratio was 0.52(14/27),the mean age ± SD was 51.5 ± 12.7 years,and the mean body mass index was 25.7 ± 3.4 kg/m 2.All subjects reported one or more LPS.Twenty-five out of 41 patients also had typical GERD symptoms(heartburn and/or regurgitation).The most frequent laryngoscopic findings were posterior laryngeal hyperemia(38/41),linear indentation in the medial edge of the vocal fold(31/41),vocal fold nodules(6/41) and diffuse infraglottic oedema(25/41).The GIS analysis showed that 10/41 patients reported symptom relief with PPI therapy(P < 0.05);conversely,23/41 did not report any clinical improvement.At the same time,the VAS analysis showed a significant reduction in typical GERD symptoms after PPI therapy(P < 0.001).A significant reduction in LPS symptoms.On the other hand,such result was not recorded for LPS.Esophagitis was detected in 2/41 patients,and ineffective esophageal motility was found in 3/41 patients.The MII-pH analysis showed an abnormal AET in 5/41 patients(2 ERD and 3 NERD);11/41 patients had a normal AET and a positive association between symptoms and refluxes(HE),and 25/41 patients had a normal AET and a negative association between symptoms and refluxes(no GERD patients).It is noteworthy that HE patients had a positive association with typical GERD-related symptoms.Gas refluxes were found more frequently in patients with globus(29.7 ± 3.6) and hoarseness(21.5 ± 7.4) than in patients with heartburn or regurgitation(7.8 ± 6.2).Gas refluxes were positively associated with extraesophageal symptoms(P < 0.05).Overall,no differences were found among the three groups of patients in terms of the frequency of laryngeal signs.The proximal reflux was abnormal in patients with ERD/NERD only.The differences observed by means of MII-pH analysis among the three subgroups of patients(ERD/NERD,HE,no GERD) were not demonstrated with the RSI and RFS.Moreover,only the number of gas refluxes was found to have a significant association with the RFS(P = 0.028 andP = 0.026,nominal and numerical correlation,respectively).CONCLUSION:MII-pH analysis confirmed GERD diagnosis in less than 40% of patients with previous diagnosis of LPR,most likely because of the low specificity of the laryngoscopic findings.展开更多
文摘To improve the electrorheological effect of electrorheological fluid (ERF), a new type of the electrosensitive particle material, polynaphthalene quinone was prepared, whose molecules contain blended atoms of nitrogen, oxygen, sulphur and big π bond conjugate system. In both DC and AC electric fields, the ERF material showed a distinct ER effect. Especially, in the alternating electric field, the shear stress of this material versus AC voltage has a better quadratic relation than that of the other materials. The experimental data showed that organic semiconductor polymers with big π bond conjugate system are a new type of electrosensitive particle materials which are worth well developing.
文摘Cyclic total reflux(CTR) batch distillation is a promising mode of the process but lacking of appropriate modeling for the period of filling the reflux drum.A new dynamic modeling method for the simulation of CTR batch distillation is proposed in this work,in which the changes in column holdup and liquid flow rate during the filling of the drum,and the consequent change in valid number of theoretical plates are considered.The effect of drum holdup on operation time is investigated and the optimal drum holdup is obtained from the simulation.The dynamic modeling is compared to the conventional modeling without consideration of change in liquid flow rate. The experimental result shows that the present modeling is more reliable and more accurate,especially for the column with large liquid holdup.
文摘AIM:To investigate the prevalence of gastroesophageal reflux disease(GERD) in patients with a laryngoscopic diagnosis of laryngopharyngeal reflux(LPR).METHODS:Between May 2011 and October 2011,41 consecutive patients with laryngopharyngeal symptoms(LPS) and laryngoscopic diagnosis of LPR were empirically treated with proton pump inhibitors(PPIs) for at least 8 wk,and the therapeutic outcome was assessed through validated questionnaires(GERD impact scale,GIS;visual analogue scale,VAS).LPR diagnosis was performed by ear,nose and throat specialists using the reflux finding score(RFS) and reflux symptom index(RSI).After a 16-d wash-out from PPIs,all patients underwent an upper endoscopy,stationary esophageal manometry,24-h multichannel intraluminal impedance and pH(MII-pH) esophageal monitoring.A positive correlation between LPR diagnosis and GERD was supposed based on the presence of esophagitis(ERD),pathological acid exposure time(AET) in the absence of esophageal erosions(NERD),and a positive correlation between symptoms and refluxes(hypersensitive esophagus,HE).RESULTS:The male/female ratio was 0.52(14/27),the mean age ± SD was 51.5 ± 12.7 years,and the mean body mass index was 25.7 ± 3.4 kg/m 2.All subjects reported one or more LPS.Twenty-five out of 41 patients also had typical GERD symptoms(heartburn and/or regurgitation).The most frequent laryngoscopic findings were posterior laryngeal hyperemia(38/41),linear indentation in the medial edge of the vocal fold(31/41),vocal fold nodules(6/41) and diffuse infraglottic oedema(25/41).The GIS analysis showed that 10/41 patients reported symptom relief with PPI therapy(P < 0.05);conversely,23/41 did not report any clinical improvement.At the same time,the VAS analysis showed a significant reduction in typical GERD symptoms after PPI therapy(P < 0.001).A significant reduction in LPS symptoms.On the other hand,such result was not recorded for LPS.Esophagitis was detected in 2/41 patients,and ineffective esophageal motility was found in 3/41 patients.The MII-pH analysis showed an abnormal AET in 5/41 patients(2 ERD and 3 NERD);11/41 patients had a normal AET and a positive association between symptoms and refluxes(HE),and 25/41 patients had a normal AET and a negative association between symptoms and refluxes(no GERD patients).It is noteworthy that HE patients had a positive association with typical GERD-related symptoms.Gas refluxes were found more frequently in patients with globus(29.7 ± 3.6) and hoarseness(21.5 ± 7.4) than in patients with heartburn or regurgitation(7.8 ± 6.2).Gas refluxes were positively associated with extraesophageal symptoms(P < 0.05).Overall,no differences were found among the three groups of patients in terms of the frequency of laryngeal signs.The proximal reflux was abnormal in patients with ERD/NERD only.The differences observed by means of MII-pH analysis among the three subgroups of patients(ERD/NERD,HE,no GERD) were not demonstrated with the RSI and RFS.Moreover,only the number of gas refluxes was found to have a significant association with the RFS(P = 0.028 andP = 0.026,nominal and numerical correlation,respectively).CONCLUSION:MII-pH analysis confirmed GERD diagnosis in less than 40% of patients with previous diagnosis of LPR,most likely because of the low specificity of the laryngoscopic findings.
