AIM: To study the process of foam floatation in the separation of Indigo Naturalis in batch mode. METHODS: Recovery of indigo and purity were chosen as the performance criteria and single examining method to examine the operational parameters,i.e.air flow rate,initial feed concentration,solution pH,initial feed volume on floatation performance. RESULTS: The floatation performance was good when gas flow rate increased from 112 L/h to 256 L/h,initial feed concentration of 0.4 g/mL,keeping the initial pH,feed volume of 1 000 mL.The purity ratio of indigo was about 2.3 and the recovery was about 90%. CONCLUSION: Foam(floatation) can be applied to the separation of Indigo Naturalis.

A new method to calculate and counterbalance the inertia force of slider-crank mechanisms in high-speed mechanical presses was put forward. By analyzing the kinematic characteristics of a center-located slider-crank mechanism whose crank rotates at a constant angular velocity, the kinematic parameters of the slide, connecting rod and crank were formulated approximately. On the basis of the results above, three inertia forces and the input moment in the mechanism during its idle running were investigated and formulated by dynamic analysis. A verification experiment was performed on a slider-crank mechanism at a high-speed press machine. The forces derived from the established formulas were compared respectively with those obtained by the ADAMS software and the classical method of connecting rod mass substitution. It was experimentally found that the proposed formulas have an improved performance over related earlier techniques. By use of these results, a 1000 kN 1250 rpm four-point high-speed press machine was designed and manufactured. The slide of this press is driven by four sets of slider-crank mechanisms with symmetrical layout and opposite rotation directions to counterbalance the horizontal inertia forces. Four eccentric counterbalance blocks were designed to counterbalance the vertical force after their mass and equivalent eccentric radius were formulated. The high-speed press machine designed by the proposed counterbalance method has worked with satisfactory performance and good dynamic balance for more than four years in practical production.

Objective Aprotinin has been suspended in cardiac surgery since risks factors associated with mortality and other adverse events in western Literatures.This study was to investigate the effect of aprotinin on short-term outcomes in cardiac surgery in Chinese patients.Methods Two groups of patients who underwent cardiac surgery during equal period just before and after aprotinin was suspended in China.Aprotinin groupp(n=1699) was defined as operations from june 19,2007 to Dec 18,2007,when aprotinin was used in all the patients.Control group(n=2225)was defined as operations from Dec19,2007 to June 18,2008,when aprotinin was not umed.Postoperative outcomes between the two groups,including blood loes and transfusion requirement,in-hospital mortality and major adveme outcome events were compared,using univariate analysis and mulfivariable logistic regression analysis.Results Aprotinin group had less postoperative blood loes,transfusion requirement and reoperation for bleeching as compared with the control group.Application of aprotinin did not increase the risk of in-hospital mortality (0.5%vs.10%,P=0.08)and other major ad-verse events,including renal dysfunction,renal failure requiring dialysis,low cardiac output syndrome (LCOS),neurological and pulmonary complications.Aprltinin group also had and shorter mechanical ventilation time(P=0.04),a lowwer rate of delayed mechan-ical ventilation time(P=0.04)and a higher PaO2/FiO2 in the bolld gas analysis(P<0.001).which presented a better respiratory function.Multivariable Logistic regression analysis got identical results with univariate analysis.Conclusion The use of aprotinin in cardiac surgery could reduce blood loss and transfusion requirement significantly,and showed a protective effect on the lungs.In the mean time it did not increase the risk of mortality or major complications.We suggest further studies should be performed to make a decision of continuing or stopping the use of aprotinin in cardisc surgery in Chinese or Asian population.

Objective To identify the independent risk factors of surgical site infections (SSIs) for patients with cholelithiasis after biliary tract surgery.Methods 712 patients were enrolled from April 2010 to April 2015 in this study and their clinical data were retrospectively analyzed.There were 106 patients who developed SSIs.The risk factors of SSIs and their three subtypes (superficial incisional SSIs,deep incisional SSIs,and organ/space SSIs) were analyzed.The total hospitalization cost,length of hospitalization and patients who stayed over 30 days in hospital were compared between the group of patients with and without SSIs.Results Univariate analysis showed that SSIs were associated with diabetes,emergency operation,bile duct re-exploration,hepatectomy,positive bile bacteria culture,porta hepatis clamping,Ⅱ-Ⅳ grades of cholelithiasis,ASA Grade 3,BMI ＞ 30,hepatic function Grade B and protein level ＜ 30 g/L on hospital admission (all P ＜ 0.05).The results also indicated that superficial incisional SSIs,deep incisional SSIs and organ/space SSIs were correlated with emergency operation,bile duct re-exploration,hepatectomy,operation time,porta hepatis clamping,smoking,ASA score and protein level on hospital admission (all P ＜ 0.05).The total hospitalization expense,length of hospital stay and the number of patients hospitalized for over 30 days in the SSIs Group were significantly more than the non-SSIs Group (all P ＜ 0.05).Bile duct re-exploration,hepatectomy,positive bile bacteria culture and Ⅱ-Ⅳ grades of cholelithiasis were independent risk factors of SSIs on multivariate unconditional logistical regression analysis (all P ＜ 0.05).Conclusions Multiple factors in the perioperative period were involved in SSIs after bile duct surgery.Bile duct te-exploration,hepatectomy,positive bile bacteria culture and Ⅱ-Ⅳ grades of cholelithiasis were independent risk factors of SSIs.

AIM:To study the mechanism of foam floatation in the processing of Indigo Raturalis,and provide theory to support the industrialization of Indigo Raturalis processing by foam fioatation technique. METHODS: To study the critical problems of the processing of Indigo Raturalis by foam floatation technique: the change of particle size distribution after the processing of Indigo Raturalis;The surface activity of frothing materials in Indigo Raturalis;the distinction of the foam to absorb the Indigo particles and other particles(CaCO_3);the absorbability of the Indigo particles to absorb different surface active agents. RESULTS: 1.The Indigo particles were easily absorbed by the foam,but others(CaCO_3) were not;2.There were some frothing materials with good frothing capability in the alkaline system of Indigo Raturalis,3 In the alkaline system,the Indigo particles could be absorbed by the foam of strong acid surface active agents. CONCLUSION: In the alkaline system of Indigo Raturalis,with itself surface active agents,it is effective to process Indigo Raturalis by foam floatation technique.

Objective To study the process of foam flotation in separation of Indigo Naturalis in a continuous mode and to optimize the operational conditions.Methods Taking content and rate of recovery rate of indigo as index to investigate the single factors,such as the height of collecting region,the height of froth layer,flushing water rate,delivery rate,air flow rate,and aerating velocity,to study the effect of continuous foam floatation on Indigo Naturalis,and to optimize the process conditions finally.Results The flotation performance is good when the height of collecting region is 1.5 m,the height of froth layer is 30 cm,the delivery rate is 0.1 cm/s,the flushing water rate is 0.01 cm/s,the aerating velocity is 1.5 cm/s.The recovery rate of indigo is more than 75% and indgo content is over 5.0%.Conclusion Foam flotation technique is stable and can be used to the separation of Indigo Naturalis in a continuous mode.And this study is the foundation of semi-works production of Indigo Naturalis.